Comparative Efficacy of PETD and PEID in the Management of L5/S1 Calcified Lumbar Disc Herniation: A Focus on Residual Calcification and Mid-Term Outcomes

Comparative Efficacy of PETD and PEID in the Management of L5/S1 Calcified Lumbar Disc Herniation: A Focus on Residual Calcification and Mid-Term Outcomes | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Comparative Efficacy of PETD and PEID in the Management of L5/S1 Calcified Lumbar Disc Herniation: A Focus on Residual Calcification and Mid-Term Outcomes Yu-qing Jiang, Wei Jiang, Meng-lei Xu, Yi-fei Shen, Nan-wei Xu, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4353380/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study is a retrospective cohort analysis of data collected from one clinical site between 2020 and 2022. The purpose of this study was to evaluate the effectiveness of two percutaneous endoscopic discectomy procedures in treating calcified lumbar discs at the L5/S1 level: percutaneous endoscopic transforaminal decompression (PETD) and percutaneous endoscopic interlaminar discectomy (PEID). Out of 117 patients who were initially enrolled, 114 completed the research. Of them, 56 had single-level chronic lumbar disc herniation and underwent PETD, whereas 58 received PEID. This breakdown was due to attrition. The Visual Analog Scale (VAS), the Oswestry Disability Index (ODI), the Japanese Orthopaedic Association Scores (JOA), and the Short Form 12-Item Health Survey (SF-12) were utilized for demographic assessments, calcification morphology, residual calcified area(CRA), complications, and function analysis analysis in the present study in addition to other instruments. At the1,3, and 12-month follow-up assessments, the PETD and PEID groups did not differ in terms of clinical outcomes. A larger CRA in the PETD group did not affect the treatment efficacy linear regression to a statistically significant degree. This suggests that the two approaches to treating chronic lumbosacral disc herniation are complementary rather than competing. Health sciences/Diseases/Neurological disorders/Neuropathic pain Health sciences/Diseases/Neurological disorders/Spinal cord diseases Percutaneous Endoscopic Transforaminal Decompression Percutaneous Endoscopic Interlaminar Discectomy Lumbar Disc Herniation Residual Calcified Area Treatment Efficacy Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Lumbar Intervertebral Disc Herniation (CLDH) is a distinct form of LDH, distinguished by the protrusion of the calcified disc material. The precise etiology of CLDH remains elusive, while contemporary research indicates that chronic inflammation may exert a promotive influence on the calcification process 1 . Iatridis et al. 2 hypothesized that the cause could be attributed to the alterations taking place in the lumbar spine as a consequence of stress. These alterations result in an inflexible framework that places an excessive amount of mechanical stress on the nerve roots. A significant proportion of these patients typically necessitate surgical intervention because to the low efficacy of conservative therapeutic methods in inducing regression in the majority of calcified discs 3 . While there is a wealth of material accessible on the basic pathology of disc herniation, there is a lack of concentrated literature specifically addressing the intricacies of CLDH and its response to different surgical methods. This discrepancy highlights the want for focused investigation to elucidate the most suitable management options that may be efficiently executed for this intricate ailment. Lastly, among the most well-known and cutting-edge treatments, Percutaneous Endoscopic Lumbar Discectomy (PELD) stands out due to its minimally invasive nature and excellent clinical results 4 . Notable variations of PELD include Percutaneous Endoscopic Transforaminal Discectomy (PETD) and Percutaneous Endoscopic Interlaminar Discectomy (PEID). Reduced surgical time, fewer complications, easier patient mobility, and shorter hospital stays are some of the main benefits of endoscopic operations 5 . In addition, they lessen the likelihood of problems and recurrences 5 . Technological advancements in endoscopy have made it easier to remove calcified discs and other obstructive structures, which helps keep the spine stable 6 . Recent developments in lumbar endoscopic technology have made it feasible to stabilize the spine while removing protruding objects like calcified discs that put pressure on the nerve root. To fully release the nerve root from calcified disc herniation, distinct and specific decompression within the spinal canal is necessary 7 . Despite their efficacy, there has been a dearth of research comparing the two in a controlled setting with CLDH, namely at the L5/S1 level. This work seeks to address the lack of information by doing a thorough examination of PETD and PEID within the context of CLDH. The findings of this study will be beneficial in improving surgical intervention tactics. Materials and methods A retrospective cohort analysis conducted at a single facility between 2020 and 2022 initially included 117 patients diagnosed with single-level CLDH at the L5/S1 level and treated with PELD. With comprehensive clinical data at our disposal, we utilized a retrospective methodology to evaluate the outcomes of these surgical procedures. The clinical ethics committee approved this research. Written informed consent was obtained from all participants, and all procedures adhered to the guidelines set by the relevant Chinese authorities and the Helsinki Declaration. Key end measures (VAS, ODI, JOA, and SF-12 scores), minimum clinically important difference (MCID), and expected to be detected difference for efficacy have been considered to find how many participants should be included in the trial, to detect efficacy between two surgical procedures (PETD and PEID). These estimates are based on the effect sizes and standard deviations estimated from previous research and pilot test studies. It was estimated that the study had 80% statistical power against an alpha error rate of 0.05. Sample size estimation was evaluated using G*Power software. To have sufficient statistical power, not less than 50 patients in each group would be necessary, totaling a minimum of 100 patients for the first sample. In this study, 117 patients were enrolled at the beginning. After all, they have been considered and analyzed as to meet the necessary statistical criteria. The inclusion criteria were carefully established to create a uniform study population, consisting of: ( 1 ) patients who had lower back pain and unilateral lower limb symptoms, such as discomfort, numbness, or weakness; and ( 2 ) patients who had CT-confirmed evidence of CLDH. The exclusion criteria were implemented to minimize potential factors that could distort the results. These criteria consisted of: ( 1 ) patients displaying indications of lumbar instability; and ( 2 ) patients with severe cardiopulmonary dysfunction, determined by an anesthesiologist to be unfit for surgical intervention based on an evaluation of their overall health status. The PETD procedure is executed via a transforaminal route as described by Yeung 8 . The surgery begins with the patient lying face down, which allows for the accurate determination of the puncture site using a C-arm X-ray apparatus. The device is usually placed 10–12 cm to the side of the midline at the afflicted level. Once local anesthetic is given, the needle is precisely positioned in the back part of the specific intervertebral disc. An anteroposterior (AP) image is initially obtained to verify the intervertebral level and ensure accurate alignment of the foramen with the intended disc region.The angulation of the C-arm is then made in such a way that a lateral view through which the insertion of the needle and advancement to the foramen's lower safe zone can be easily seen. This procedure minimizes the chances of root injury. This guidewire is then passed through the needle, which is withdrawn in order to facilitate placement of a bone drill over the guidewire, aiming to enlarge the intervertebral foramen carefully by removing bone. This creates a pathway for the insertion of electrocoagulation devices and forceps, clearly defining the surgical area and making it easier to make an incision in the ligamentum flavum to reach the disc space. The operative cannula is skillfully maneuvered to safeguard neighboring nerve structures while the calcified portions of the disc are observed and systematically eliminated using a fast-rotating drill, with a constant flow of saline solution to minimize the possibility of heat-related harm. After removing the calcifications, the primary goal is to fully decompress the disc space, while optimizing the preservation of the good disc tissue. Following decompression, a comprehensive evaluation of the nerve root is conducted to confirm the absence of compression or bleeding, effectively alleviating symptoms. The treatment concludes with the removal of the endoscopic equipment, suturing the skin, and applying a sterile bandage to the incision site (Fig. 1 A). The PEID technique is performed through an interlaminar approach according to Ruetten 9 . This technique is initiated with the patient under general anesthesia, in a prone position to optimize surgical access. A small, 1 cm horizontal incision is made approximately 2 cm lateral to the spinous process at the involved level. The puncture needle is precisely positioned at the specified section, and then a pencil head and working cannula are inserted through a 0.7 cm incision. The placement is confirmed using a C-arm X-ray system. After removing the pencil head, the working cannula is filled with irrigation fluid, preparing for the insertion of the endoscope. The outermost layers of the ligamentum flavum are carefully removed, followed by a precise cut into the ligamentum flavum to reduce the risk of harming the nerves beneath it. When there is stenosis, the surgeon strategically removes the medial facet joint edge and a part of the lamina bone according to the preoperative plan in order to assist decompression. Utilizing specialized instruments, a segment of the ligamentum flavum is excised, revealing the underlying nerve root and dural sac. Care is taken to gently maneuver the working cannula around the nerve retractor, avoiding direct nerve contact, to access and remove the calcified disc material, mirroring the approach employed in the PETD technique. (Fig. 1 B). Following the operation, a standard postoperative care plan was put in place for all these patients in a bid to optimize recovery outcomes. The plan of care entailed an elaborate method of pain management, individualized physical therapy programs, and careful wound care. Individualized pain management plans were made in relation to each patient's pain tolerance and advancement in recovery in order to keep the level of pain to a minimum so that early movement was encouraged. When the patient's condition allowed, early physical therapy was initiated. The program focused on enhancing muscle strength, increasing flexibility, and promoting functional mobility. The enhancement of muscle strength with time, coupled with increased flexibility and easier functional mobility, was noteworthy. The main goals were to teach the patient good body mechanics and offer advice on exercises that would help them avoid having back problems in the future. This included treating wounds with strict aseptic methods to avoid infection and keeping a close eye out for any signs of problems. Patients were advised to initiate ambulation promptly following the surgical procedure, in accordance with the recommendations provided by the healthcare staff. It is highly recommended to include the patient in a rehabilitation program to expedite a full recovery process and ensure a return to the former level of activity and quality of life following the surgery. The principal outcomes measured in this study included the Oswestry Disability Index (ODI) score, Visual Analog Scale (VAS) score for pain, Japanese Orthopaedic Association (JOA) Score related to functional recovery for low back, and the 12-item Short Form Health Survey Physical Composite Score (SF-12 PCS) for the physical health quality. These all were laboriously collated measured indicators of successful surgical interventions at discrete time points over the follow-up period of 1, 3, and 12 months after the operation, respectively. In addition to the primary outcomes, a comprehensive set of secondary outcomes were also evaluated to provide a holistic view of the treatment effects. These included detailed patient demographics, the preoperative diagnosis, and the morphology of calcification as classified by the Wu Scoring System. The calcification residual area (CRA) of the intervertebral disc, along with the percentage of CRA (S%), was carefully measured to assess the extent of calcification removal. Other parameters collected included the segment of operation, duration of surgery, volume of blood lost intra-operatively, and time spent in bed after surgery and in overall length of hospital stay. The postoperative complications were carefully documented to determine the security profile of the surgical procedures. Within 48 hours post-surgery, patients received high-resolution computerized tomography (CT) scans to obtain fine-grain images of the calcified lumbar discs. High-resolution CT is perhaps the most effective way to obtain crisp and accurate images of the bone and its calcifications. The quantification of the remaining calcified area was performed independently by two experienced radiologists using the ImageJ software (National Institutes of Health, USA). The area of calcification was established through a comparison of pre- and post-operative disc imaging, with the estimation of the area of residual calcification represented as a percentage of the whole disc calcification. Pearson Correlation Coefficients were estimated to quantify linear associations between residual calcified area and the functional scores (VAS, ODI, JOA, SF-12). Moreover, the use of statistical analysis has been used to get the need for using a multivariate linear regression model to account for relevant confounding variables such as age, gender, BMI, and surgery parameters. This may have been possible because such confounders had been controlled during the research and might be having an impact on postoperative functional recovery. The statistical and well-structured analysis guaranteed a solid assessment of the gathered data. When applicable to the paper, the continuous variables, such as the SF-12 PCS, ODI, JOA, and VAS scores, were reported as means ± standard deviations (SD). In respect to patient demographics and complications, mean scores were compared between the groups of patients who were admitted and those who were discharged. The Student t-test, which is pertinent to comparing means in situations when the data are regularly distributed, was employed for this purpose. For categorical variables, descriptive analyses included patient demographics and specific complications represented as percentage frequencies and numbers. Chi-square testing was used as the primary analytical tool for the data, along with all other statistical techniques. The software has incorporated the Fisher-Freeman-Halton test, which is a generalization of Fisher's exact test, to ensure the validity of all results in the event of low predicted frequencies. Using the Pearson correlation coefficient, we examined the linear relationship between the variables in this study—calculated area and functional scores—one at a time. Statistical analyses were conducted using SPSS 22.0 (IBM Corp., Armonk, NY) for all but the Fisher-Freeman-Halton test, which was used to determine the frequency of postoperative complications in the previous section. With a p -value less than 0.05, the null hypothesis was rejected due to statistically significant differences. This indicates a notable difference between the PETD and PEID groups in the analyzed outcomes. Results There were 117 patients in the study who were diagnosed with single-level CLDH at the L5/S1 level. Of them, 57 were treated with PETD and 60 with PEID. Due to attrition, follow-up data were available for 114 patients: 56 who underwent PETD after 1 was lost to follow-up, and 58 who underwent PEID after 2 were lost to follow-up. There were no statistically significant differences between the groups, ensuring comparability, according to a complete investigation of demographic and clinical parameters ( P > 0.05, reported in Table 1 ). Notably, both groups had very low attrition rates throughout the 12-month follow-up period: 1.75% (1/57) in the PETD group and 3.33% (2/60) in the PEID group, with a chi-square value of 0.307 (P = 0.579) indicating that neither group was significantly different. There was also painstaking documentation and analysis of surgical factors like intraoperative blood loss, operation duration, hospital stay length, and postoperative bed rest period. These surgical parameters were found to be consistently applied across the cohort, as shown by the independent samples t-test, which found no significant differences between the two groups. Table 2 presents a comprehensive tabulation of these surgical characteristics along with their statistical analysis, offering a clear picture of the operational elements of the surgical treatments. The assessment of pain intensity was quantitatively measured, right from lower back pain to leg pain, using the Visual Analog Scale (VAS) at preoperative and successive follow-up intervals post-surgery in the patient population. Comparatively, no significant difference in the VAS scores was noted between the PETD and PEID groups at any of the follow-up points (1, 3, 12 months postoperative) by statistical analysis. Notably, scores actually showed significant improvement in both groups compared to the preoperative baseline, as they do not significantly differ from each other. Specifically, in relation to low back and leg pain, the VAS scores of the PETD group were 6.50 ± 1.062 at preoperative and 1.43 ± 0.499 at 12 months postoperative, while for the PEID group, they were 6.60 ± 1.091 at the preoperative stage and 1.48 ± 0.504 postoperatively at 12 months. Clearly, therefore, the efficacy of either surgical approach in pain management was not statistically different ( P > 0.05 for all comparisons, illustrated in Fig. 2 ). This highlighted the fact that PETD is an equally efficient method as PEID for pain relief, an inevitable component for patient recovery and satisfaction. Both groups demonstrated comparable improvements in ODI scores (68.45 ± 4.994 / 30.45 ± 2.411 / 17.20 ± 1.976 / 7.77 ± 1.640 vs. 67.66 ± 5.128 / 30.28 ± 2.720 / 16.60 ± 2.143 / 8.07 ± 1.715, P > 0.05) preoperatively and at 1, 3, and 12 months postoperatively. Similarly, JOA scores (9.25 ± 1.352 / 21.79 ± 1.345 / 23.84 ± 1.156 / 26.57 ± 1.110 vs. 8.95 ± 1.616 / 22.07 ± 1.282 / 24.14 ± 1.220 / 26.71 ± 1.076, P > 0.05), indicating the degree of functional recovery, showed no significant differences between the two groups. Additionally, SF-12 scores (29.39 ± 4.575 / 36.71 ± 3.971 / 43.21 ± 4.658 / 51.23 ± 5.271 vs. 30.57 ± 4.100 / 37.05 ± 3.868 / 44.21 ± 3.986 / 51.09 ± 4.921, P > 0.05), reflecting health-related quality of life, demonstrated similar trends between the two groups preoperatively and at 1, 3, and 12 months postoperatively (Fig. 2 ). Figure 3 displays serious consequences; nonetheless, all patients were promptly and effectively treated. We assessed the following issues: Injuries to the nervous system, blood vessels, or dura mater, temporary numbness or pain in the lower extremities, weakness in the psoas or quadriceps, infection at the surgical site, deep vein thrombosis, readmission, or revision. Neurological injury, vascular injury, dural tears, transient limb pain/numbness, weakness of the psoas or quadriceps, infection of the surgical site, deep vein thromboembolism, readmission, and revision were all not reported in the PETD group. In contrast, the PEID group experienced a total of one case of neural injury, one case of vascular injury, three cases of dural tears, seven cases of transient lower limb pain/numbness, five cases of weakness in the psoas or quadriceps, one case of infection at the surgical site, zero cases of deep venous thromboembolism, two readmissions, and one revision. In terms of postoperative complications, there was no statistically significant difference between the PETD and PEID groups (19.6% [11/56] vs. 36.2% [21/58], P = 0.33, χ 2 = 1.959). The intraobserver and interobserver intraclass correlation coefficients for morphology and CRA % were comparable, ranging from 0.85 to 0.95. There was no apparent difference between the PETD and PEID groups in terms of morphology (χ2 = 0.14, P = 0.93). Therefore, the PETD group had a considerably greater CRA percentage than the PEID group (67.39 ± 17.86 vs. 34.91 ± 10.32, T = 11.94, P < 0.001). Table 2 showed all detailed data. Figure 4 presented typical examples. A full correlation analysis was done to clarify how the residual calcification influences the recovery track of the patients after spine operations. In this study, we tried to find out if there is any relation between the volume of residual calcification after surgery and functional results postoperatively at one, three, and twelve months. The items considered as outcomes were the Visual Analogue Scale, and SF-12 for overall health quality. These are summarized in Table 3 by treatment group: Group 1 represents PETD, and Group 2 represents PEID. These associations are given by correlation coefficients for each outcome measure at other postoperative times in Fig. 5 . These results portray the intricate interplay of functional ratings at various surgical time periods with residual calcification. This could be realized by better postoperative care and improved patient outcomes, which are able to explain these associations in order to show how residual calcification might influence recovery trajectories. Table 1 Patient characteristics. Data are presented as mean ± standard deviation or number of patients. T/χ 2 values indicate the statistics from t-tests or chi-square tests for continuous and categorical variables, respectively. PETD: Percutaneous Endoscopic Transforaminal Discectomy, PEID: Percutaneous Endoscopic Interlaminar Discectomy. Variable PETD (n = 56) PEID (n = 58) T/χ2 Values P Value Disease duration (months) 2.55 ± 1.21 2.69 ± 1.14 -0.65 0.50 Age 42.30 ± 10.61 44.93 ± 10.80 -1.31 0.19 Sex 1.46 ± 0.50 1.62 ± 0.49 2.81 0.09 Female 30 22 Male 26 36 BMI 23.99 ± 2.73 24.31 ± 3.45 -0.55 0.59 Morphology type 0.14 0.93 Isolated type 7 7 Half-lunar type 20 19 Successive type 29 32 Table 2 Perioperative Data. Data are presented as mean ± standard deviation. T/χ 2 values indicate the statistics from t-tests or chi-square tests for continuous variables. PETD: Percutaneous Endoscopic Transforaminal Discectomy; PEID: Percutaneous Endoscopic Interlaminar Discectomy; CRA: Calcification Residual Area of the intervertebral disc. Variable PETD (n = 56) PEID (n = 58) T/χ2 Value P Value Blood loss 39.11 ± 28.92 30.69 ± 21.79 1.76 0.08 Operation time 98.02 ± 29.51 104.78 ± 38.95 -1.04 0.30 Hospital stay 7.61 ± 2.13 8.09 ± 3.34 -0.91 0.36 Time in bed 2.73 ± 0.75 2.69 ± 0.65 0.32 0.75 CRA Percentage 67.39 ± 17.86 34.91 ± 10.32 11.94 0.00 Table 3 Correlation Coefficients between Residual Calcification Area and Postoperative Outcome Measures. AS: Visual Analog Scale; ODI: Oswestry Disability Index; JOA: Japanese Orthopaedic Association score; SF-12: Short Form ( 12 ) Health Survey; Corr: Correlation Coefficient; Post-op 1M: Postoperative 1 Month; Post-op 3M: Postoperative 3 Months; Post-op 1Y: Postoperative 1 Year. Group Timepoint VAS Corr ODI Corr JOA Corr SF-12 Corr PETD Post-op 1M 0.0437 0.1917 0.0047 -0.1631 PETD Post-op 3M 0.2128 0.2769 0.0777 0.0231 PETD Post-op 1Y -0.1796 -0.1169 0.0402 0.0645 PEID Post-op 1M 0.1600 0.0303 -0.0406 -0.1229 PEID Post-op 3M -0.0845 -0.0176 0.1176 -0.0451 PEID Post-op 1Y 0.1382 0.1590 -0.0122 -0.1252 Discussion When compared to conventional posterior incisions, minimally invasive therapy techniques like spinal endoscopy have clear benefits, such as less surgical trauma and faster patient recovery 10 . There is a growing amount of evidence that these procedures are effective and safe for the treatment of calcified lumbar disc herniation (CLDH), but their use is still debatable and difficult to implement 11,12 . Researchers have shown that CLDH therapies carry a slightly higher risk of side effects than non-calcified lumbar disc herniations, possibly because calcification is more complex. This finding is supported by studies such as Dabo et al. 13 . While there is an elevated frequency of early postoperative paresthesia and medication use in CLDH, Choi et al. 14 have explained how the interlaminar method offers a safe and effective means of treating axillary-type disc herniations at the L5/S1 level. Despite the rates of early postoperative paresthesia and postoperative drug use in CLDH being significantly greater than those in soft disc herniation 15 , the interlaminar approach is still recommended for central or paracentral CLDH, which can make bone resection easier and expand the operating space to facilitate reaching the lesion directly, thereby reducing surgical complications 13,16 . A Prospective Randomized Controlled Study on L5–S1 Disc Herniation showed that PEID has more advantages than PETD, such as the ability to escape the blockade of the iliac crest, faster puncture orientation, shorter operation time, and less intraoperative radiation exposure 17 . A meta-analysis also indicated that, although there were no significant differences in postoperative Visual Analog Scale (VAS), Oswestry Disability Index, and the rate of complications between the interlaminar approach and the transforaminal approach in treating L5/S1 disc herniation, the former had a shorter operation time and fewer intraoperative fluoroscopy exposures 18 . However, this study found no significant difference in operative time between the two surgical methods for treating CLDH, but there was a significant difference in the postoperative area of the calcified intervertebral disc (PEID significantly smaller than PETD). Notably, one of the prospective randomized controlled studies comparing PEID and PETD found that PEID had an advantage over PETD—less obstruction of the iliac crest and intraoperative radiation exposure 17 . Our study does not show any statistically significant difference in the operative time between PETD and PEID in the surgical management of CLDH. This would imply both techniques are equally efficacious, but PEID shows an outcome that could be more preferable in some clinical situations since a smaller calcified area would require postoperative removal 18 . The Wu scoring system is a tool for assessing the degree and shape of calcification, which is crucial for determining surgical decisions 11 . There was no statistically significant difference in morphology between the groups when we utilized this grading system to assess calcification patterns between patients of CLDH treated with PETD and PEID. Thus, both methods are still useful for managing the calcified discs' physical characteristics. When deciding on a surgical strategy, the precise anatomical site of the calcification should be the first and foremost consideration. Research has shown that due to PETD's lateral access capacity, it is more effective when utilized to treat disc herniations in the lateral lumbar region 19 . In contrast, a PEID would allow for direct access and straightforward bone resection, making it the superior method for managing central or paracentral calcifications. Because we did not have any instances in our series with severe lateral protrusion, we cannot say how well PEID worked in this circumstance. All protocols used in this study, YESS 8 , TESSYS 20 , and the Peak Method 11 , were with regard to the surgical resection scope in question. Based on preoperative CT and MRI sagittal and cross-sectional images, the site of incision was made to take out the compressive calcified intervertebral disc. During the operation, the precise location of the incision was modified as needed. Using a burr, the surgeon was able to partially remove osseous structures from the facet joints and laminae that could have obstructed the surgical field or the visual field (Fig. 1 ). Critically, substantial disturbance of the facet joint, which could jeopardize lumbar stability, was more detrimental than damage to the facet joint itself 21,22 . Due to the narrow operative field and diversity in the size and position of calcifications, effective removal of the calcified discs presents substantial technical obstacles. Lei Yu proposed using ultrasonic bone scalpels to reduce neurovascular hazards during calcified disc removal; this unique surgical approach and tool has demonstrated potential in improving safety and efficacy 6 . In order to ensure treatment efficacy and accomplish the maximal range of resection, Yu Chen et al. used the patient's CT images of the calcified intervertebral disc to preoperatively alter the surgical corridor width 6 . However, larger-scale research is necessary to validate these strategies and to monitor their efficacy and reliability for a long time. The necessity of complete calcified intervertebral disc removal remains a topic of debate. A compelling study indicated that in PETD treatment for CLDH, favorable therapeutic results could still be achieved even if some calcified intervertebral disc remnants persisted in the central or asymptomatic regions 23 . Our research supports this conclusion by showing that similar surgical outcomes were observed regardless of the amount of residual calcified intervertebral disc. There is a dearth of strong research in the literature at the moment that connects the amount of calcified intervertebral disc excision to the stability of the spine. Meta-analyses suggest minimal differences in the restoration of spinal force lines between PETD and PEID, likely attributable to the minimal bone disruption inherent in both techniques 24 . Such minor alterations do not typically precipitate lumbar instability. Moreover, the primary objective of these surgical interventions is to relieve nerve compression rather than achieve total disc removal. Overzealous excision of calcified discs might escalate risks, such as epidural bleeding, which could exert undue pressure on the spinal cord. Therefore, meticulous intraoperative management of bleeding is crucial. Techniques include the precise cauterization of small blood vessels around the calcified discs and dura mater before burring, and applying bone wax to the burr to minimize bleeding during the removal of calcified lesions. Such targeted cauterization also serves a hemostatic function. There is currently no study that links the extent of disc degeneration clearance to enhanced spinal stability. There may be an unproven negative association between the quantity of disc protrusion removed and therapeutic efficacy, as extensive removal of soft tissue and bone could damage lumbar stability. This reemphasizes the need for more research to outline the effects of the different amounts of calcified disc removal on long-term spinal health. It would be a tricky situation to choose one of these two techniques for the treatment of CLDH, as one deals with a set of challenges. Both surgical procedures have a significant risk of dural tear or leakage of cerebrospinal fluid. It was found that there is an association with PETD and a decreased overall incidence of dural and neurovascular complications, while PEID had a high rate of persistent lower limb symptoms. In addition, the rates of postoperative infection and functional insufficiency of the lower extremity were not statistically different between groups. This proves the fact that surgical approaches need to be individualized based on each patient's anatomy and medical necessity. The present study has great importance and value in the treatment of L5/S1 calcified lumbar disc herniation using PETD and PEID; it provides a good overview of the outcomes and the recurrence of lumbar disc herniation. One major limitation is the relatively smaller cohort in a retrospective observational study, which may not rule out the potential for selection bias. While this follow-up duration of 12 months gives a fair idea about the early outcomes of the surgical procedures, it might not actually mirror the long-term outcomes and associated complications of the surgeries. Further large randomized controlled trials with a more extended follow-up are required to confirm these results and to learn more about the safety and efficacy of these surgical procedures in the long term. Both PETD and PEID are equally valid and safe solution methods in treating calcified LDH at the L5/S1 level with almost similar therapeutic effects in relieving chronic low back pain and increasing quality of life without a high rate of adverse effects. Although amenable and reproducible, the best approach depends on patient anatomy, location of the calcified disc, and surgical expertise. Specifically, our study did not exhibit any association of the residual calcification area with the therapeutic response, which might be attributed to the limit of surgical methods or inherent difficulties in completely eliminating the calcified areas of technical or anatomical nature. Moreover, the fact that calcification is in a different place and of a different type, and differences in the assessment methods of each respective study, and individual patient variation may, in part, influence these findings. PEID presented a clear advantage in minimizing residual calcification that may be affecting more on long-term outcomes than PETD and thus warrants further study. Further support to these preliminary findings and seeking possible mechanisms that may explain differences, the prospective study of a random, double-blind design would be warranted. This would further enlighten and refine the surgical strategies for the patient-specific treatment outcome. Declarations Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Author Contribution Involved in design of the study (Y.-q.J., W.J., L.H.); data collection (Y.-q.J., W.J., M.-l.X.); analysis and interpretation of data (M.-l.X., Y.-f.S., N.-w.X.); prepared figures (M.-l.X.); writing the article (Y.-q.J., L.H.); and having primary responsibility for final content (L.H.). All authors read, reviewed and approved the manuscript. Acknowledgement Acknowledgements:None. Data Availability The data that support the findings of this study are available on request from the corresponding author, L.H. References Grangeat, A. M. & Erario, M. L. A. The Use of Medical Ozone in Chronic Intervertebral Disc Degeneration Can Be an Etiological and Conservative Treatment. Int J Mol Sci. 24, 6538. https://doi.org/10.3390/ijms24076538 (2023). Iatridis, J. C., Setton, L. A., Weidenbaum, M. & Mow, V. C. Alterations in the mechanical behavior of the human lumbar nucleus pulposus with degeneration and aging. J Orthop Res. 15, 318–322. https://doi.org/10.1002/jor.1100150224 (1997). Utter, A. et al. Spontaneous regression and near disappearance of a calcified herniated thoracic disc in a 44-year-old male: illustrative case. J Neurosurg Case Lessons. 1, CASE2130. https://doi.org/10.3171/CASE2130 (2021). Ma, C. et al. Percutaneous Endoscopic Lumbar Discectomy for Huge Lumbar Disc Herniation with Complete Dural Sac Stenosis via an Interlaminar Approach: An Observational Retrospective Cohort Study. Int J Gen Med. 14, 8317–8324. https://doi.org/10.2147/IJGM.S341309 (2021). Pan, M. et al. Percutaneous Endoscopic Lumbar Discectomy: Indications and Complications. Pain Physician. 23, 49–56. (2020). Yu, L. et al. Removal of calcified lumbar disc herniation with endoscopic-matched ultrasonic osteotome - Our preliminary experience. Br J Neurosurg. 34, 80–85. https://doi.org/10.1080/02688697.2019.1687850 (2020). Li, W. S. et al. Comparison of Endoscopic Discectomy Versus Non-Endoscopic Discectomy for Symptomatic Lumbar Disc Herniation: A Systematic Review and Meta-Analysis. Global Spine J. 12, 1012–1026. https://doi.org/10.1177/21925682211020696 (2022). Tsou, P. M. & Yeung, A. T. Transforaminal endoscopic decompression for radiculopathy secondary to intracanal noncontained lumbar disc herniations: outcome and technique. Spine J. 2, 41–48. https://doi.org/10.1016/s1529-9430(01)00153-x (2002). Ruetten, S., Komp, M. & Godolias, G. A New full-endoscopic technique for the interlaminar operation of lumbar disc herniations using 6-mm endoscopes: prospective 2-year results of 331 patients. Minim Invasive Neurosurg. 49, 80–87. https://doi.org/10.1055/s-2006-932172 (2006). Aldahshory, A. R. et al. Comparative Study of Minimally Invasive Lumbar Decompression versus Decompressive Laminectomy with Posterolateral Transpedicular Fixation for the Treatment of Degenerative Lumbar Canal Stenosis. Asian J Neurosurg. 15, 293–301. https://doi.org/10.4103/ajns.AJNS_132_20 (2020). Wang, H. et al. Evaluation of efficacy and safety of percutaneous transforaminal endoscopic surgery (PTES) for surgical treatment of calcified lumbar disc herniation: a retrospective cohort study of 101 patients. BMC Musculoskelet Disord. 22, 65. https://doi.org/10.1186/s12891-020-03938-3 (2021). Shin, S. H. et al. Transforaminal Endoscopic Discectomy for Hard or Calcified Lumbar Disc Herniation: A New Surgical Technique and Clinical Outcomes. World Neurosurg. 143, e224–e231. https://doi.org/10.1016/j.wneu.2020.07.113 (2020). Dabo, X. et al. The Clinical Results of Percutaneous Endoscopic Interlaminar Discectomy (PEID) in the Treatment of Calcified Lumbar Disc Herniation: A Case-Control Study. Pain Physician. 19, 69–76. (2016). Choi, G. et al. Percutaneous endoscopic interlaminar discectomy for intracanalicular disc herniations at L5-S1 using a rigid working channel endoscope. Neurosurgery. 58, ONS59–68; discussion ONS59–68. https://doi.org/10.1227/01.neu.0000192713.95921.4a (2006). Chen, Y. et al. Percutaneous Endoscopic Lumbar Discectomy in Treating Calcified Lumbar Intervertebral Disc Herniation. World Neurosurg. 122, e1449–e1456. https://doi.org/10.1016/j.wneu.2018.11.083 (2019). Chen, W. et al. Clinical effects of transforaminal approach vs interlaminar approach in treating lumbar disc herniation: A clinical study protocol. Medicine (Baltimore). 99, e22701. https://doi.org/10.1097/MD.0000000000022701 (2020). Nie, H. et al. Percutaneous Endoscopic Lumbar Discectomy for L5-S1 Disc Herniation Via an Interlaminar Approach Versus a Transforaminal Approach: A Prospective Randomized Controlled Study With 2-Year Follow Up. Spine (Phila Pa 1976). 41 Suppl 19, B30–B37. https://doi.org/10.1097/BRS.0000000000001810 (2016). Yin, J. et al. Transforaminal approach versus interlaminar approach: A meta-analysis of operative complication of percutaneous endoscopic lumbar discectomy. Medicine (Baltimore). 99, e20709. https://doi.org/10.1097/MD.0000000000020709 (2020). Lin, H. et al. [Treatment of L₄,₅ lumbar disc herniation with percutaneous endoscopic lumbar discectomy through two different approaches]. Zhongguo Gu Shang. 32, 904–909. https://doi.org/10.3969/j.issn.1003-0034.2019.10.006 (2019). Schubert, M. & Hoogland, T. Endoscopic transforaminal nucleotomy with foraminoplasty for lumbar disk herniation. Oper Orthop Traumatol. 17, 641–661. https://doi.org/10.1007/s00064-005-1156-9 (2005). Yu, Y. et al. Effect of Percutaneous Endoscopic Lumbar Foraminoplasty of Different Facet Joint Portions on Lumbar Biomechanics: A Finite Element Analysis. Orthop Surg. 12, 1277–1284. https://doi.org/10.1111/os.12740 (2020). Ikeda, S. et al. Facet joint thickness and lumbar instability documented on myelo-computed tomography studies in patients with lumbar degenerative disease. Surg Neurol Int. 14, 342. https://doi.org/10.25259/SNI_652_2023 (2023). Yuan, A. L. et al. Treatment of Calcified Lumbar Disc Herniation by Intervertebral Foramen Remolding: A Retrospective Study. J Pain Res. 15, 1719–1728. https://doi.org/10.2147/JPR.S357033 (2022). Pan, M. et al. Percutaneous Endoscopic Lumbar Discectomy: Indications and Complications. Pain Physician. 23, 49–56. (2020). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4353380","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":300575334,"identity":"d8e856b7-f519-48f9-9ce3-cf029a897c81","order_by":0,"name":"Yu-qing Jiang","email":"","orcid":"","institution":"Changzhou No.2 People's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yu-qing","middleName":"","lastName":"Jiang","suffix":""},{"id":300575335,"identity":"edd9b0d2-cff3-44f6-bb5a-4cb30ae28939","order_by":1,"name":"Wei Jiang","email":"","orcid":"","institution":"Changzhou No.2 People's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Wei","middleName":"","lastName":"Jiang","suffix":""},{"id":300575336,"identity":"68046257-9358-45c7-8b09-6189b03323ef","order_by":2,"name":"Meng-lei Xu","email":"","orcid":"","institution":"Changzhou No.2 People's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Meng-lei","middleName":"","lastName":"Xu","suffix":""},{"id":300575337,"identity":"fb32c987-445e-4d98-92f1-17c119f3243e","order_by":3,"name":"Yi-fei Shen","email":"","orcid":"","institution":"Changzhou No.2 People's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yi-fei","middleName":"","lastName":"Shen","suffix":""},{"id":300575338,"identity":"9275cf3f-7bfb-473b-b47c-8ac043fda69b","order_by":4,"name":"Nan-wei Xu","email":"","orcid":"","institution":"Changzhou No.2 People's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Nan-wei","middleName":"","lastName":"Xu","suffix":""},{"id":300575339,"identity":"9deb1f7c-d27d-40a4-9291-3ac3e84abc81","order_by":5,"name":"Long Han","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4klEQVRIiWNgGAWjYDCCAwzMYJqNgYeB4YOBjR1JWhgbZxSkJROvhQGopZnnwyHGBkI6+I6ffWz4o+JOHh//2uOPbQwOMDOwHz66AZ8WyTPpxsk8Z54Vs0m8S2zOMbjDx8CTlnYDnxaDA2nMhxnbDie2SZwxBGp5xswgwWOGX8v5Z8wHf8K0WBgcZmwgqOVGGnMCL0gLf49hMwMxWiRvPGM25jkDsoXHcGaPQVoyGyG/8J1PY5b8UXE4cX7/GYMPP/7Y2PGzHz6GVwsCSCRAaDbilIMA/wHi1Y6CUTAKRsHIAgAgfk6TXPNrOQAAAABJRU5ErkJggg==","orcid":"","institution":"Changzhou No.2 People's Hospital","correspondingAuthor":true,"prefix":"","firstName":"Long","middleName":"","lastName":"Han","suffix":""}],"badges":[],"createdAt":"2024-05-01 09:10:36","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4353380/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4353380/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":56542480,"identity":"a42f8d66-0de1-4632-8cf6-3acce692389f","added_by":"auto","created_at":"2024-05-15 14:32:11","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":422003,"visible":true,"origin":"","legend":"\u003cp\u003eIllustration depicting the utilization of visual field range in PETD and PEID approaches for the removal of calcified lumbar disc protrusion. A, PETD involves partial removal of the superior articular process (highlighted in orange-yellow, semi-elliptical region) to enhance the visual scope of the calcified disc (marked by the blue-black transition zone within the protruding spinal canal area). The primary objective is to maximize the excision of the herniated disc material. B, PEID entails partial removal of the lamina (highlighted in orange-yellow, diamond-shaped region) to expand the visual field range of the calcified disc (indicated by the blue-black transition zone within the protruding spinal canal area). The primary goal is to optimize the removal of the herniated disc material.\u003c/p\u003e","description":"","filename":"floatimage1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4353380/v1/f5a7b92f5432d40b13923ea5.jpg"},{"id":56543624,"identity":"e515f985-3ec8-4d8d-8696-44402d1b1d75","added_by":"auto","created_at":"2024-05-15 14:40:11","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":305242,"visible":true,"origin":"","legend":"\u003cp\u003eResults of the VAS, ODI, JOA, and SF-12 during the perioperative period in the PETD and PEID groups. We compared the patient groups' VAS, ODI, JOA, and SF-12 scores before surgery, 1, 3, and 12 months after the procedure. Both groups' pain and functional scores changed significantly after surgery when compared to their preoperative baselines. There was no significant difference found in score comparison between groups at each time point.\u003c/p\u003e","description":"","filename":"floatimage2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4353380/v1/efd1ef302c07766aac1b2d03.jpg"},{"id":56544238,"identity":"92806c75-8494-461d-8190-d2d61b672b10","added_by":"auto","created_at":"2024-05-15 14:48:11","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":195753,"visible":true,"origin":"","legend":"\u003cp\u003eThe bar graph compares the incidence of both perioperative and postoperative complications between the two groups: PETD and PEID. The orange-colored bars represent the occurrence in the PEID group, while the bars colored blue denote the occurrence in the PETD group.\u003c/p\u003e","description":"","filename":"floatimage3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4353380/v1/9ac9730ff46b1d5653f7d86e.jpg"},{"id":56542484,"identity":"a63499fe-cf6a-41b9-8ae0-919e45ef7221","added_by":"auto","created_at":"2024-05-15 14:32:11","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":2051471,"visible":true,"origin":"","legend":"\u003cp\u003eA 59-year-old male and a 38-year-old female were both diagnosed with L5-S1 calcified lumbar disc herniation and underwent PETD (A-E) and PEID surgery respectively. In images A, B, F, and G, the black arrows represent the protruding calcified intervertebral discs. During the procedure, the calcified protrusion within the field of view was removed using a burr. Postoperative CT scans revealed a significant reduction in the area of the calcified intervertebral disc. (A) The sleeve protects and mobilizes the nerve root, uncovering the calcified lesion protrusion (black arrow). (B) The burr is engaged in removing the part of the calcified lesion protrusion. (C) The excision of the calcified lesion discloses dural sinking, signaling successful decompression. (D) Preoperative CT of PETD illustrates the extent of the calcified intervertebral disc protrusion into the spinal canal, with the calcified area marked by a dashed red line. (E) Postoperative CT of PETD delineates the extent of the calcified intervertebral disc protrusion into the spinal canal, showing a reduction in the calcified area indicated by the dashed red line. (F) Under a lamina mirror, the calcified lesion is observed elevating the dura and compressing it to one side. (G) The burr is engaged in removing the part of the calcified lesion protrusion. (H) The excision of the calcified lesion unveils a dural vacancy. (I) Preoperative CT of PEID illustrates the extent of calcified intervertebral disc protruding into the spinal canal, with the calcified area marked by a dashed red line. (J) Postoperative CT of PEID delineates the extent of calcified intervertebral disc protruding into the spinal canal, with a significant reduction in the calcified area shown by the dashed red line.\u003c/p\u003e","description":"","filename":"floatimage4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4353380/v1/707d7f0a238056ca2435d6f5.jpg"},{"id":56542483,"identity":"40268bbf-38f7-4d7b-9ba6-6c84c9488712","added_by":"auto","created_at":"2024-05-15 14:32:11","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":792106,"visible":true,"origin":"","legend":"\u003cp\u003eInvestigation of the Time-Related Correlation Between Postoperative Residual Area and Functional Outcomes in PETD and PEID Settings. By comparing the PETD and PEID groups at1,3, and 12 months post-operatively, this study aimed to identify any correlations between residual disc area and functional outcomes such as VAS, ODI, JOA, and SF-12. The scatter plots show multiple functional outcome metrics, with data points divided by surgical group in each row. There was no correlation between the extent of the residual area and improvements in any of the functional outcome measures that were statistically examined. The data suggest that functional recovery as measured by VAS, ODI, JOA, and SF-12 scores is not directly proportional to the amount of material eliminated. This suggests that functional recovery as measured by VAS, ODI, JOA, and SF-12 scores may not be directly correlated with the amount of disc material removed.\u003c/p\u003e","description":"","filename":"floatimage5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4353380/v1/b1eac373a285f1483e7af5bf.jpg"},{"id":79577221,"identity":"a1abc107-f6e6-4a6b-b76f-f4e8ffc4161a","added_by":"auto","created_at":"2025-03-31 11:23:58","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4282375,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4353380/v1/c3a80349-4075-4a1e-be87-964f7ff37790.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparative Efficacy of PETD and PEID in the Management of L5/S1 Calcified Lumbar Disc Herniation: A Focus on Residual Calcification and Mid-Term Outcomes","fulltext":[{"header":"Introduction","content":"\u003cp\u003eLumbar Intervertebral Disc Herniation (CLDH) is a distinct form of LDH, distinguished by the protrusion of the calcified disc material. The precise etiology of CLDH remains elusive, while contemporary research indicates that chronic inflammation may exert a promotive influence on the calcification process\u003csup\u003e1\u003c/sup\u003e. Iatridis et al.\u003csup\u003e2\u003c/sup\u003e hypothesized that the cause could be attributed to the alterations taking place in the lumbar spine as a consequence of stress. These alterations result in an inflexible framework that places an excessive amount of mechanical stress on the nerve roots. A significant proportion of these patients typically necessitate surgical intervention because to the low efficacy of conservative therapeutic methods in inducing regression in the majority of calcified discs\u003csup\u003e3\u003c/sup\u003e. While there is a wealth of material accessible on the basic pathology of disc herniation, there is a lack of concentrated literature specifically addressing the intricacies of CLDH and its response to different surgical methods. This discrepancy highlights the want for focused investigation to elucidate the most suitable management options that may be efficiently executed for this intricate ailment.\u003c/p\u003e \u003cp\u003eLastly, among the most well-known and cutting-edge treatments, Percutaneous Endoscopic Lumbar Discectomy (PELD) stands out due to its minimally invasive nature and excellent clinical results\u003csup\u003e4\u003c/sup\u003e. Notable variations of PELD include Percutaneous Endoscopic Transforaminal Discectomy (PETD) and Percutaneous Endoscopic Interlaminar Discectomy (PEID). Reduced surgical time, fewer complications, easier patient mobility, and shorter hospital stays are some of the main benefits of endoscopic operations\u003csup\u003e5\u003c/sup\u003e. In addition, they lessen the likelihood of problems and recurrences\u003csup\u003e5\u003c/sup\u003e. Technological advancements in endoscopy have made it easier to remove calcified discs and other obstructive structures, which helps keep the spine stable\u003csup\u003e6\u003c/sup\u003e. Recent developments in lumbar endoscopic technology have made it feasible to stabilize the spine while removing protruding objects like calcified discs that put pressure on the nerve root. To fully release the nerve root from calcified disc herniation, distinct and specific decompression within the spinal canal is necessary\u003csup\u003e7\u003c/sup\u003e. Despite their efficacy, there has been a dearth of research comparing the two in a controlled setting with CLDH, namely at the L5/S1 level.\u003c/p\u003e \u003cp\u003eThis work seeks to address the lack of information by doing a thorough examination of PETD and PEID within the context of CLDH. The findings of this study will be beneficial in improving surgical intervention tactics.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003eA retrospective cohort analysis conducted at a single facility between 2020 and 2022 initially included 117 patients diagnosed with single-level CLDH at the L5/S1 level and treated with PELD. With comprehensive clinical data at our disposal, we utilized a retrospective methodology to evaluate the outcomes of these surgical procedures. The clinical ethics committee approved this research. Written informed consent was obtained from all participants, and all procedures adhered to the guidelines set by the relevant Chinese authorities and the Helsinki Declaration.\u003c/p\u003e \u003cp\u003eKey end measures (VAS, ODI, JOA, and SF-12 scores), minimum clinically important difference (MCID), and expected to be detected difference for efficacy have been considered to find how many participants should be included in the trial, to detect efficacy between two surgical procedures (PETD and PEID). These estimates are based on the effect sizes and standard deviations estimated from previous research and pilot test studies. It was estimated that the study had 80% statistical power against an alpha error rate of 0.05. Sample size estimation was evaluated using G*Power software. To have sufficient statistical power, not less than 50 patients in each group would be necessary, totaling a minimum of 100 patients for the first sample. In this study, 117 patients were enrolled at the beginning. After all, they have been considered and analyzed as to meet the necessary statistical criteria.\u003c/p\u003e \u003cp\u003eThe inclusion criteria were carefully established to create a uniform study population, consisting of: (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) patients who had lower back pain and unilateral lower limb symptoms, such as discomfort, numbness, or weakness; and (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) patients who had CT-confirmed evidence of CLDH. The exclusion criteria were implemented to minimize potential factors that could distort the results. These criteria consisted of: (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) patients displaying indications of lumbar instability; and (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) patients with severe cardiopulmonary dysfunction, determined by an anesthesiologist to be unfit for surgical intervention based on an evaluation of their overall health status.\u003c/p\u003e \u003cp\u003eThe PETD procedure is executed via a transforaminal route as described by Yeung\u003csup\u003e8\u003c/sup\u003e. The surgery begins with the patient lying face down, which allows for the accurate determination of the puncture site using a C-arm X-ray apparatus. The device is usually placed 10\u0026ndash;12 cm to the side of the midline at the afflicted level. Once local anesthetic is given, the needle is precisely positioned in the back part of the specific intervertebral disc. An anteroposterior (AP) image is initially obtained to verify the intervertebral level and ensure accurate alignment of the foramen with the intended disc region.The angulation of the C-arm is then made in such a way that a lateral view through which the insertion of the needle and advancement to the foramen's lower safe zone can be easily seen. This procedure minimizes the chances of root injury. This guidewire is then passed through the needle, which is withdrawn in order to facilitate placement of a bone drill over the guidewire, aiming to enlarge the intervertebral foramen carefully by removing bone. This creates a pathway for the insertion of electrocoagulation devices and forceps, clearly defining the surgical area and making it easier to make an incision in the ligamentum flavum to reach the disc space. The operative cannula is skillfully maneuvered to safeguard neighboring nerve structures while the calcified portions of the disc are observed and systematically eliminated using a fast-rotating drill, with a constant flow of saline solution to minimize the possibility of heat-related harm. After removing the calcifications, the primary goal is to fully decompress the disc space, while optimizing the preservation of the good disc tissue. Following decompression, a comprehensive evaluation of the nerve root is conducted to confirm the absence of compression or bleeding, effectively alleviating symptoms. The treatment concludes with the removal of the endoscopic equipment, suturing the skin, and applying a sterile bandage to the incision site (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA). The PEID technique is performed through an interlaminar approach according to Ruetten\u003csup\u003e9\u003c/sup\u003e. This technique is initiated with the patient under general anesthesia, in a prone position to optimize surgical access. A small, 1 cm horizontal incision is made approximately 2 cm lateral to the spinous process at the involved level. The puncture needle is precisely positioned at the specified section, and then a pencil head and working cannula are inserted through a 0.7 cm incision. The placement is confirmed using a C-arm X-ray system. After removing the pencil head, the working cannula is filled with irrigation fluid, preparing for the insertion of the endoscope. The outermost layers of the ligamentum flavum are carefully removed, followed by a precise cut into the ligamentum flavum to reduce the risk of harming the nerves beneath it. When there is stenosis, the surgeon strategically removes the medial facet joint edge and a part of the lamina bone according to the preoperative plan in order to assist decompression. Utilizing specialized instruments, a segment of the ligamentum flavum is excised, revealing the underlying nerve root and dural sac. Care is taken to gently maneuver the working cannula around the nerve retractor, avoiding direct nerve contact, to access and remove the calcified disc material, mirroring the approach employed in the PETD technique. (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFollowing the operation, a standard postoperative care plan was put in place for all these patients in a bid to optimize recovery outcomes. The plan of care entailed an elaborate method of pain management, individualized physical therapy programs, and careful wound care. Individualized pain management plans were made in relation to each patient's pain tolerance and advancement in recovery in order to keep the level of pain to a minimum so that early movement was encouraged. When the patient's condition allowed, early physical therapy was initiated. The program focused on enhancing muscle strength, increasing flexibility, and promoting functional mobility. The enhancement of muscle strength with time, coupled with increased flexibility and easier functional mobility, was noteworthy. The main goals were to teach the patient good body mechanics and offer advice on exercises that would help them avoid having back problems in the future. This included treating wounds with strict aseptic methods to avoid infection and keeping a close eye out for any signs of problems. Patients were advised to initiate ambulation promptly following the surgical procedure, in accordance with the recommendations provided by the healthcare staff. It is highly recommended to include the patient in a rehabilitation program to expedite a full recovery process and ensure a return to the former level of activity and quality of life following the surgery.\u003c/p\u003e \u003cp\u003eThe principal outcomes measured in this study included the Oswestry Disability Index (ODI) score, Visual Analog Scale (VAS) score for pain, Japanese Orthopaedic Association (JOA) Score related to functional recovery for low back, and the 12-item Short Form Health Survey Physical Composite Score (SF-12 PCS) for the physical health quality. These all were laboriously collated measured indicators of successful surgical interventions at discrete time points over the follow-up period of 1, 3, and 12 months after the operation, respectively.\u003c/p\u003e \u003cp\u003eIn addition to the primary outcomes, a comprehensive set of secondary outcomes were also evaluated to provide a holistic view of the treatment effects. These included detailed patient demographics, the preoperative diagnosis, and the morphology of calcification as classified by the Wu Scoring System. The calcification residual area (CRA) of the intervertebral disc, along with the percentage of CRA (S%), was carefully measured to assess the extent of calcification removal. Other parameters collected included the segment of operation, duration of surgery, volume of blood lost intra-operatively, and time spent in bed after surgery and in overall length of hospital stay. The postoperative complications were carefully documented to determine the security profile of the surgical procedures.\u003c/p\u003e \u003cp\u003eWithin 48 hours post-surgery, patients received high-resolution computerized tomography (CT) scans to obtain fine-grain images of the calcified lumbar discs. High-resolution CT is perhaps the most effective way to obtain crisp and accurate images of the bone and its calcifications. The quantification of the remaining calcified area was performed independently by two experienced radiologists using the ImageJ software (National Institutes of Health, USA). The area of calcification was established through a comparison of pre- and post-operative disc imaging, with the estimation of the area of residual calcification represented as a percentage of the whole disc calcification. Pearson Correlation Coefficients were estimated to quantify linear associations between residual calcified area and the functional scores (VAS, ODI, JOA, SF-12). Moreover, the use of statistical analysis has been used to get the need for using a multivariate linear regression model to account for relevant confounding variables such as age, gender, BMI, and surgery parameters. This may have been possible because such confounders had been controlled during the research and might be having an impact on postoperative functional recovery.\u003c/p\u003e \u003cp\u003eThe statistical and well-structured analysis guaranteed a solid assessment of the gathered data. When applicable to the paper, the continuous variables, such as the SF-12 PCS, ODI, JOA, and VAS scores, were reported as means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations (SD). In respect to patient demographics and complications, mean scores were compared between the groups of patients who were admitted and those who were discharged. The Student t-test, which is pertinent to comparing means in situations when the data are regularly distributed, was employed for this purpose. For categorical variables, descriptive analyses included patient demographics and specific complications represented as percentage frequencies and numbers. Chi-square testing was used as the primary analytical tool for the data, along with all other statistical techniques. The software has incorporated the Fisher-Freeman-Halton test, which is a generalization of Fisher's exact test, to ensure the validity of all results in the event of low predicted frequencies. Using the Pearson correlation coefficient, we examined the linear relationship between the variables in this study\u0026mdash;calculated area and functional scores\u0026mdash;one at a time.\u003c/p\u003e \u003cp\u003eStatistical analyses were conducted using SPSS 22.0 (IBM Corp., Armonk, NY) for all but the Fisher-Freeman-Halton test, which was used to determine the frequency of postoperative complications in the previous section. With a \u003cem\u003ep\u003c/em\u003e-value less than 0.05, the null hypothesis was rejected due to statistically significant differences. This indicates a notable difference between the PETD and PEID groups in the analyzed outcomes.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThere were 117 patients in the study who were diagnosed with single-level CLDH at the L5/S1 level. Of them, 57 were treated with PETD and 60 with PEID. Due to attrition, follow-up data were available for 114 patients: 56 who underwent PETD after 1 was lost to follow-up, and 58 who underwent PEID after 2 were lost to follow-up. There were no statistically significant differences between the groups, ensuring comparability, according to a complete investigation of demographic and clinical parameters (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05, reported in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Notably, both groups had very low attrition rates throughout the 12-month follow-up period: 1.75% (1/57) in the PETD group and 3.33% (2/60) in the PEID group, with a chi-square value of 0.307 (P\u0026thinsp;=\u0026thinsp;0.579) indicating that neither group was significantly different.\u003c/p\u003e \u003cp\u003eThere was also painstaking documentation and analysis of surgical factors like intraoperative blood loss, operation duration, hospital stay length, and postoperative bed rest period. These surgical parameters were found to be consistently applied across the cohort, as shown by the independent samples t-test, which found no significant differences between the two groups. Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e presents a comprehensive tabulation of these surgical characteristics along with their statistical analysis, offering a clear picture of the operational elements of the surgical treatments.\u003c/p\u003e \u003cp\u003eThe assessment of pain intensity was quantitatively measured, right from lower back pain to leg pain, using the Visual Analog Scale (VAS) at preoperative and successive follow-up intervals post-surgery in the patient population. Comparatively, no significant difference in the VAS scores was noted between the PETD and PEID groups at any of the follow-up points (1, 3, 12 months postoperative) by statistical analysis. Notably, scores actually showed significant improvement in both groups compared to the preoperative baseline, as they do not significantly differ from each other. Specifically, in relation to low back and leg pain, the VAS scores of the PETD group were 6.50\u0026thinsp;\u0026plusmn;\u0026thinsp;1.062 at preoperative and 1.43\u0026thinsp;\u0026plusmn;\u0026thinsp;0.499 at 12 months postoperative, while for the PEID group, they were 6.60\u0026thinsp;\u0026plusmn;\u0026thinsp;1.091 at the preoperative stage and 1.48\u0026thinsp;\u0026plusmn;\u0026thinsp;0.504 postoperatively at 12 months. Clearly, therefore, the efficacy of either surgical approach in pain management was not statistically different (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05 for all comparisons, illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). This highlighted the fact that PETD is an equally efficient method as PEID for pain relief, an inevitable component for patient recovery and satisfaction.\u003c/p\u003e \u003cp\u003eBoth groups demonstrated comparable improvements in ODI scores (68.45\u0026thinsp;\u0026plusmn;\u0026thinsp;4.994 / 30.45\u0026thinsp;\u0026plusmn;\u0026thinsp;2.411 / 17.20\u0026thinsp;\u0026plusmn;\u0026thinsp;1.976 / 7.77\u0026thinsp;\u0026plusmn;\u0026thinsp;1.640 vs. 67.66\u0026thinsp;\u0026plusmn;\u0026thinsp;5.128 / 30.28\u0026thinsp;\u0026plusmn;\u0026thinsp;2.720 / 16.60\u0026thinsp;\u0026plusmn;\u0026thinsp;2.143 / 8.07\u0026thinsp;\u0026plusmn;\u0026thinsp;1.715, P\u0026thinsp;\u0026gt;\u0026thinsp;0.05) preoperatively and at 1, 3, and 12 months postoperatively. Similarly, JOA scores (9.25\u0026thinsp;\u0026plusmn;\u0026thinsp;1.352 / 21.79\u0026thinsp;\u0026plusmn;\u0026thinsp;1.345 / 23.84\u0026thinsp;\u0026plusmn;\u0026thinsp;1.156 / 26.57\u0026thinsp;\u0026plusmn;\u0026thinsp;1.110 vs. 8.95\u0026thinsp;\u0026plusmn;\u0026thinsp;1.616 / 22.07\u0026thinsp;\u0026plusmn;\u0026thinsp;1.282 / 24.14\u0026thinsp;\u0026plusmn;\u0026thinsp;1.220 / 26.71\u0026thinsp;\u0026plusmn;\u0026thinsp;1.076, P\u0026thinsp;\u0026gt;\u0026thinsp;0.05), indicating the degree of functional recovery, showed no significant differences between the two groups. Additionally, SF-12 scores (29.39\u0026thinsp;\u0026plusmn;\u0026thinsp;4.575 / 36.71\u0026thinsp;\u0026plusmn;\u0026thinsp;3.971 / 43.21\u0026thinsp;\u0026plusmn;\u0026thinsp;4.658 / 51.23\u0026thinsp;\u0026plusmn;\u0026thinsp;5.271 vs. 30.57\u0026thinsp;\u0026plusmn;\u0026thinsp;4.100 / 37.05\u0026thinsp;\u0026plusmn;\u0026thinsp;3.868 / 44.21\u0026thinsp;\u0026plusmn;\u0026thinsp;3.986 / 51.09\u0026thinsp;\u0026plusmn;\u0026thinsp;4.921, P\u0026thinsp;\u0026gt;\u0026thinsp;0.05), reflecting health-related quality of life, demonstrated similar trends between the two groups preoperatively and at 1, 3, and 12 months postoperatively (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e displays serious consequences; nonetheless, all patients were promptly and effectively treated. We assessed the following issues: Injuries to the nervous system, blood vessels, or dura mater, temporary numbness or pain in the lower extremities, weakness in the psoas or quadriceps, infection at the surgical site, deep vein thrombosis, readmission, or revision. Neurological injury, vascular injury, dural tears, transient limb pain/numbness, weakness of the psoas or quadriceps, infection of the surgical site, deep vein thromboembolism, readmission, and revision were all not reported in the PETD group. In contrast, the PEID group experienced a total of one case of neural injury, one case of vascular injury, three cases of dural tears, seven cases of transient lower limb pain/numbness, five cases of weakness in the psoas or quadriceps, one case of infection at the surgical site, zero cases of deep venous thromboembolism, two readmissions, and one revision. In terms of postoperative complications, there was no statistically significant difference between the PETD and PEID groups (19.6% [11/56] vs. 36.2% [21/58], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.33, χ\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;1.959).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe intraobserver and interobserver intraclass correlation coefficients for morphology and CRA % were comparable, ranging from 0.85 to 0.95. There was no apparent difference between the PETD and PEID groups in terms of morphology (χ2\u0026thinsp;=\u0026thinsp;0.14, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.93). Therefore, the PETD group had a considerably greater CRA percentage than the PEID group (67.39\u0026thinsp;\u0026plusmn;\u0026thinsp;17.86 vs. 34.91\u0026thinsp;\u0026plusmn;\u0026thinsp;10.32, T\u0026thinsp;=\u0026thinsp;11.94, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e showed all detailed data. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e presented typical examples.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eA full correlation analysis was done to clarify how the residual calcification influences the recovery track of the patients after spine operations. In this study, we tried to find out if there is any relation between the volume of residual calcification after surgery and functional results postoperatively at one, three, and twelve months. The items considered as outcomes were the Visual Analogue Scale, and SF-12 for overall health quality. These are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e by treatment group: Group 1 represents PETD, and Group 2 represents PEID. These associations are given by correlation coefficients for each outcome measure at other postoperative times in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. These results portray the intricate interplay of functional ratings at various surgical time periods with residual calcification. This could be realized by better postoperative care and improved patient outcomes, which are able to explain these associations in order to show how residual calcification might influence recovery trajectories.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePatient characteristics. Data are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation or number of patients. T/χ\u003csup\u003e2\u003c/sup\u003e values indicate the statistics from t-tests or chi-square tests for continuous and categorical variables, respectively. PETD: Percutaneous Endoscopic Transforaminal Discectomy, PEID: Percutaneous Endoscopic Interlaminar Discectomy.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePETD (n\u0026thinsp;=\u0026thinsp;56)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePEID (n\u0026thinsp;=\u0026thinsp;58)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT/χ2 Values\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP Value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDisease duration (months)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.55\u0026thinsp;\u0026plusmn;\u0026thinsp;1.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.69\u0026thinsp;\u0026plusmn;\u0026thinsp;1.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e-0.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.50\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42.30\u0026thinsp;\u0026plusmn;\u0026thinsp;10.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e44.93\u0026thinsp;\u0026plusmn;\u0026thinsp;10.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e-1.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.19\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.46\u0026thinsp;\u0026plusmn;\u0026thinsp;0.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.62\u0026thinsp;\u0026plusmn;\u0026thinsp;0.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23.99\u0026thinsp;\u0026plusmn;\u0026thinsp;2.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24.31\u0026thinsp;\u0026plusmn;\u0026thinsp;3.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e-0.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.59\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMorphology type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.93\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIsolated type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHalf-lunar type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSuccessive type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePerioperative Data. Data are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation. T/χ\u003csup\u003e2\u003c/sup\u003e values indicate the statistics from t-tests or chi-square tests for continuous variables. PETD: Percutaneous Endoscopic Transforaminal Discectomy; PEID: Percutaneous Endoscopic Interlaminar Discectomy; CRA: Calcification Residual Area of the intervertebral disc.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePETD (n\u0026thinsp;=\u0026thinsp;56)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePEID (n\u0026thinsp;=\u0026thinsp;58)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eT/χ2 Value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP Value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood loss\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e39.11\u0026thinsp;\u0026plusmn;\u0026thinsp;28.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e30.69\u0026thinsp;\u0026plusmn;\u0026thinsp;21.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOperation time\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e98.02\u0026thinsp;\u0026plusmn;\u0026thinsp;29.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e104.78\u0026thinsp;\u0026plusmn;\u0026thinsp;38.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e-1.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHospital stay\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e7.61\u0026thinsp;\u0026plusmn;\u0026thinsp;2.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e8.09\u0026thinsp;\u0026plusmn;\u0026thinsp;3.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e-0.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.36\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime in bed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.73\u0026thinsp;\u0026plusmn;\u0026thinsp;0.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.69\u0026thinsp;\u0026plusmn;\u0026thinsp;0.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.75\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCRA Percentage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e67.39\u0026thinsp;\u0026plusmn;\u0026thinsp;17.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e34.91\u0026thinsp;\u0026plusmn;\u0026thinsp;10.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e11.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCorrelation Coefficients between Residual Calcification Area and Postoperative Outcome Measures. AS: Visual Analog Scale; ODI: Oswestry Disability Index; JOA: Japanese Orthopaedic Association score; SF-12: Short Form (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e) Health Survey; Corr: Correlation Coefficient; Post-op 1M: Postoperative 1 Month; Post-op 3M: Postoperative 3 Months; Post-op 1Y: Postoperative 1 Year.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGroup\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTimepoint\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eVAS Corr\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eODI Corr\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eJOA Corr\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eSF-12 Corr\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePETD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePost-op 1M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.0437\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.1917\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.0047\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e-0.1631\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePETD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePost-op 3M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.2128\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.2769\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.0777\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.0231\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePETD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePost-op 1Y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.1796\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e-0.1169\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.0402\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.0645\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePEID\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePost-op 1M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.1600\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.0303\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-0.0406\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e-0.1229\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePEID\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePost-op 3M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.0845\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e-0.0176\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.1176\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e-0.0451\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePEID\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePost-op 1Y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.1382\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.1590\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-0.0122\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e-0.1252\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWhen compared to conventional posterior incisions, minimally invasive therapy techniques like spinal endoscopy have clear benefits, such as less surgical trauma and faster patient recovery\u003csup\u003e10\u003c/sup\u003e. There is a growing amount of evidence that these procedures are effective and safe for the treatment of calcified lumbar disc herniation (CLDH), but their use is still debatable and difficult to implement\u003csup\u003e11,12\u003c/sup\u003e. Researchers have shown that CLDH therapies carry a slightly higher risk of side effects than non-calcified lumbar disc herniations, possibly because calcification is more complex. This finding is supported by studies such as Dabo et al.\u003csup\u003e13\u003c/sup\u003e. While there is an elevated frequency of early postoperative paresthesia and medication use in CLDH, Choi et al.\u003csup\u003e14\u003c/sup\u003e have explained how the interlaminar method offers a safe and effective means of treating axillary-type disc herniations at the L5/S1 level. Despite the rates of early postoperative paresthesia and postoperative drug use in CLDH being significantly greater than those in soft disc herniation\u003csup\u003e15\u003c/sup\u003e, the interlaminar approach is still recommended for central or paracentral CLDH, which can make bone resection easier and expand the operating space to facilitate reaching the lesion directly, thereby reducing surgical complications\u003csup\u003e13,16\u003c/sup\u003e. A Prospective Randomized Controlled Study on L5\u0026ndash;S1 Disc Herniation showed that PEID has more advantages than PETD, such as the ability to escape the blockade of the iliac crest, faster puncture orientation, shorter operation time, and less intraoperative radiation exposure\u003csup\u003e17\u003c/sup\u003e. A meta-analysis also indicated that, although there were no significant differences in postoperative Visual Analog Scale (VAS), Oswestry Disability Index, and the rate of complications between the interlaminar approach and the transforaminal approach in treating L5/S1 disc herniation, the former had a shorter operation time and fewer intraoperative fluoroscopy exposures\u003csup\u003e18\u003c/sup\u003e. However, this study found no significant difference in operative time between the two surgical methods for treating CLDH, but there was a significant difference in the postoperative area of the calcified intervertebral disc (PEID significantly smaller than PETD).\u003c/p\u003e \u003cp\u003eNotably, one of the prospective randomized controlled studies comparing PEID and PETD found that PEID had an advantage over PETD\u0026mdash;less obstruction of the iliac crest and intraoperative radiation exposure\u003csup\u003e17\u003c/sup\u003e. Our study does not show any statistically significant difference in the operative time between PETD and PEID in the surgical management of CLDH. This would imply both techniques are equally efficacious, but PEID shows an outcome that could be more preferable in some clinical situations since a smaller calcified area would require postoperative removal\u003csup\u003e18\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe Wu scoring system is a tool for assessing the degree and shape of calcification, which is crucial for determining surgical decisions\u003csup\u003e11\u003c/sup\u003e. There was no statistically significant difference in morphology between the groups when we utilized this grading system to assess calcification patterns between patients of CLDH treated with PETD and PEID. Thus, both methods are still useful for managing the calcified discs' physical characteristics. When deciding on a surgical strategy, the precise anatomical site of the calcification should be the first and foremost consideration. Research has shown that due to PETD's lateral access capacity, it is more effective when utilized to treat disc herniations in the lateral lumbar region\u003csup\u003e19\u003c/sup\u003e. In contrast, a PEID would allow for direct access and straightforward bone resection, making it the superior method for managing central or paracentral calcifications. Because we did not have any instances in our series with severe lateral protrusion, we cannot say how well PEID worked in this circumstance. All protocols used in this study, YESS\u003csup\u003e8\u003c/sup\u003e, TESSYS\u003csup\u003e20\u003c/sup\u003e, and the Peak Method\u003csup\u003e11\u003c/sup\u003e, were with regard to the surgical resection scope in question. Based on preoperative CT and MRI sagittal and cross-sectional images, the site of incision was made to take out the compressive calcified intervertebral disc. During the operation, the precise location of the incision was modified as needed. Using a burr, the surgeon was able to partially remove osseous structures from the facet joints and laminae that could have obstructed the surgical field or the visual field (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Critically, substantial disturbance of the facet joint, which could jeopardize lumbar stability, was more detrimental than damage to the facet joint itself\u003csup\u003e21,22\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eDue to the narrow operative field and diversity in the size and position of calcifications, effective removal of the calcified discs presents substantial technical obstacles. Lei Yu proposed using ultrasonic bone scalpels to reduce neurovascular hazards during calcified disc removal; this unique surgical approach and tool has demonstrated potential in improving safety and efficacy\u003csup\u003e6\u003c/sup\u003e. In order to ensure treatment efficacy and accomplish the maximal range of resection, Yu Chen et al. used the patient's CT images of the calcified intervertebral disc to preoperatively alter the surgical corridor width\u003csup\u003e6\u003c/sup\u003e. However, larger-scale research is necessary to validate these strategies and to monitor their efficacy and reliability for a long time.\u003c/p\u003e \u003cp\u003eThe necessity of complete calcified intervertebral disc removal remains a topic of debate. A compelling study indicated that in PETD treatment for CLDH, favorable therapeutic results could still be achieved even if some calcified intervertebral disc remnants persisted in the central or asymptomatic regions\u003csup\u003e23\u003c/sup\u003e. Our research supports this conclusion by showing that similar surgical outcomes were observed regardless of the amount of residual calcified intervertebral disc.\u003c/p\u003e \u003cp\u003eThere is a dearth of strong research in the literature at the moment that connects the amount of calcified intervertebral disc excision to the stability of the spine. Meta-analyses suggest minimal differences in the restoration of spinal force lines between PETD and PEID, likely attributable to the minimal bone disruption inherent in both techniques\u003csup\u003e24\u003c/sup\u003e. Such minor alterations do not typically precipitate lumbar instability. Moreover, the primary objective of these surgical interventions is to relieve nerve compression rather than achieve total disc removal. Overzealous excision of calcified discs might escalate risks, such as epidural bleeding, which could exert undue pressure on the spinal cord. Therefore, meticulous intraoperative management of bleeding is crucial. Techniques include the precise cauterization of small blood vessels around the calcified discs and dura mater before burring, and applying bone wax to the burr to minimize bleeding during the removal of calcified lesions. Such targeted cauterization also serves a hemostatic function.\u003c/p\u003e \u003cp\u003eThere is currently no study that links the extent of disc degeneration clearance to enhanced spinal stability. There may be an unproven negative association between the quantity of disc protrusion removed and therapeutic efficacy, as extensive removal of soft tissue and bone could damage lumbar stability. This reemphasizes the need for more research to outline the effects of the different amounts of calcified disc removal on long-term spinal health.\u003c/p\u003e \u003cp\u003eIt would be a tricky situation to choose one of these two techniques for the treatment of CLDH, as one deals with a set of challenges. Both surgical procedures have a significant risk of dural tear or leakage of cerebrospinal fluid. It was found that there is an association with PETD and a decreased overall incidence of dural and neurovascular complications, while PEID had a high rate of persistent lower limb symptoms. In addition, the rates of postoperative infection and functional insufficiency of the lower extremity were not statistically different between groups. This proves the fact that surgical approaches need to be individualized based on each patient's anatomy and medical necessity.\u003c/p\u003e \u003cp\u003eThe present study has great importance and value in the treatment of L5/S1 calcified lumbar disc herniation using PETD and PEID; it provides a good overview of the outcomes and the recurrence of lumbar disc herniation. One major limitation is the relatively smaller cohort in a retrospective observational study, which may not rule out the potential for selection bias. While this follow-up duration of 12 months gives a fair idea about the early outcomes of the surgical procedures, it might not actually mirror the long-term outcomes and associated complications of the surgeries. Further large randomized controlled trials with a more extended follow-up are required to confirm these results and to learn more about the safety and efficacy of these surgical procedures in the long term.\u003c/p\u003e \u003cp\u003eBoth PETD and PEID are equally valid and safe solution methods in treating calcified LDH at the L5/S1 level with almost similar therapeutic effects in relieving chronic low back pain and increasing quality of life without a high rate of adverse effects. Although amenable and reproducible, the best approach depends on patient anatomy, location of the calcified disc, and surgical expertise. Specifically, our study did not exhibit any association of the residual calcification area with the therapeutic response, which might be attributed to the limit of surgical methods or inherent difficulties in completely eliminating the calcified areas of technical or anatomical nature. Moreover, the fact that calcification is in a different place and of a different type, and differences in the assessment methods of each respective study, and individual patient variation may, in part, influence these findings. PEID presented a clear advantage in minimizing residual calcification that may be affecting more on long-term outcomes than PETD and thus warrants further study. Further support to these preliminary findings and seeking possible mechanisms that may explain differences, the prospective study of a random, double-blind design would be warranted. This would further enlighten and refine the surgical strategies for the patient-specific treatment outcome.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eInvolved in design of the study (Y.-q.J., W.J., L.H.); data collection (Y.-q.J., W.J., M.-l.X.); analysis and interpretation of data (M.-l.X., Y.-f.S., N.-w.X.); prepared figures (M.-l.X.); writing the article (Y.-q.J., L.H.); and having primary responsibility for final content (L.H.). All authors read, reviewed and approved the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eAcknowledgements:None.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe data that support the findings of this study are available on request from the corresponding author, L.H.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eGrangeat, A. M. \u0026amp; Erario, M. L. A. The Use of Medical Ozone in Chronic Intervertebral Disc Degeneration Can Be an Etiological and Conservative Treatment. Int J Mol Sci. 24, 6538. https://doi.org/10.3390/ijms24076538 (2023).\u003c/li\u003e\n\u003cli\u003eIatridis, J. C., Setton, L. A., Weidenbaum, M. \u0026amp; Mow, V. C. Alterations in the mechanical behavior of the human lumbar nucleus pulposus with degeneration and aging. J Orthop Res. 15, 318\u0026ndash;322. https://doi.org/10.1002/jor.1100150224 (1997).\u003c/li\u003e\n\u003cli\u003eUtter, A. et al. 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(2020).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Percutaneous Endoscopic Transforaminal Decompression, Percutaneous Endoscopic Interlaminar Discectomy, Lumbar Disc Herniation, Residual Calcified Area, Treatment Efficacy","lastPublishedDoi":"10.21203/rs.3.rs-4353380/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4353380/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study is a retrospective cohort analysis of data collected from one clinical site between 2020 and 2022. The purpose of this study was to evaluate the effectiveness of two percutaneous endoscopic discectomy procedures in treating calcified lumbar discs at the L5/S1 level: percutaneous endoscopic transforaminal decompression (PETD) and percutaneous endoscopic interlaminar discectomy (PEID). Out of 117 patients who were initially enrolled, 114 completed the research. Of them, 56 had single-level chronic lumbar disc herniation and underwent PETD, whereas 58 received PEID. This breakdown was due to attrition. The Visual Analog Scale (VAS), the Oswestry Disability Index (ODI), the Japanese Orthopaedic Association Scores (JOA), and the Short Form 12-Item Health Survey (SF-12) were utilized for demographic assessments, calcification morphology, residual calcified area(CRA), complications, and function analysis analysis in the present study in addition to other instruments. At the1,3, and 12-month follow-up assessments, the PETD and PEID groups did not differ in terms of clinical outcomes. A larger CRA in the PETD group did not affect the treatment efficacy linear regression to a statistically significant degree. This suggests that the two approaches to treating chronic lumbosacral disc herniation are complementary rather than competing.\u003c/p\u003e","manuscriptTitle":"Comparative Efficacy of PETD and PEID in the Management of L5/S1 Calcified Lumbar Disc Herniation: A Focus on Residual Calcification and Mid-Term Outcomes","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-05-15 14:32:06","doi":"10.21203/rs.3.rs-4353380/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"003d41f4-6c1d-4d63-a0f0-4ff8d0b6e7e6","owner":[],"postedDate":"May 15th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":31714391,"name":"Health sciences/Diseases/Neurological disorders/Neuropathic pain"},{"id":31714392,"name":"Health sciences/Diseases/Neurological disorders/Spinal cord diseases"}],"tags":[],"updatedAt":"2025-03-31T11:23:43+00:00","versionOfRecord":[],"versionCreatedAt":"2024-05-15 14:32:06","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4353380","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4353380","identity":"rs-4353380","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}