The safety and efficiency of a new strategy to remove the well-fixed cementless acetabular components in revision hip arthroplasty: a retrospective comparative study

The safety and efficiency of a new strategy to remove the well-fixed cementless acetabular components in revision hip arthroplasty: a retrospective comparative study | 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 Research Article The safety and efficiency of a new strategy to remove the well-fixed cementless acetabular components in revision hip arthroplasty: a retrospective comparative study Minghao Zhang, Yutao Yang, Shiguang Lai, Weijun Wang, Qing Jiang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7773136/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 07 Feb, 2026 Read the published version in BMC Musculoskeletal Disorders → Version 1 posted 16 You are reading this latest preprint version Abstract Background Removing a well-fixed acetabular cup is technically challenging with the risk of complications during revision hip arthroplasty. A new strategy was developed to detach the cup from the acetabulum by impacting on the ring with a designed instrument. This study aimed to investigate the safety and efficiency of the new strategy in removing the well-fixed acetabular components by comparing them with those removed using the Explant Acetabular Cup Removal System. Methods This retrospective study included 70 patients who underwent revision total hip arthroplasty in our center between 2019 and 2022. Patients with acetabular removed by the new technique (n = 32) or the Explant System (ES) were recruited (n = 38), followed up for a minimum of 2 years. The new strategy aimed to break the connection between bone and cup by impacting on the ring of cup with a designed instrument to create a vertical shear force (VSF) along the hemispherical shape of the acetabular surface. The diameter of the removed and re-implanted cup, severity of acetabular bone defect, hip joint function score, and complications were retrieved and compared between the two groups. The Wilcoxon-Mann–Whitney test (two-tailed) was used to assess intergroup differences in the acetabular cup size, bone defect severity, preoperative and final follow-up Harris Hip Scores (HHS). Intergroup differences in bone grafting and metal augment utilization were analyzed using chi-square tests. Results The average and median diameter of the revised cup was 1.7 mm and 2 mm larger than that of the removed cup in the VSF group, while 3.2 mm and 3.0 mm in the ES group. Metal augments were more frequently used in the ES group than in the VSF group. The patients were followed up for an average of 34 months in the VSF group and 50 months in the ES group, and none of them required re-revision due to acetabular component loosening. The mean HHS improved in both groups. Conclusion The VSF strategy is safe, efficient, and cost-effective in removing the well-fixed acetabular cup while preserving bone stock during revision hip arthroplasty. total hip arthroplasty revision implant removal vertical shear force bone defect Figures Figure 1 Figure 2 Figure 3 Figure 4 Background The volume of revision hip arthroplasty has kept increasing in the last decade, with over 36,000 procedures expected to be performed in the United States by 2030 [ 1 ]. Revision surgeries involve removing failed implants and reconstructing the hip with new ones, where a well-fixed acetabular cup is generally preserved to minimize the damage and simplify the surgery. However, removal of a well-fixed implant is necessary in certain scenarios - such as periprosthetic joint infection, recurrent dislocation due to malposition of the implant, impingement, broken locking mechanism, or the desired liner type is unavailable et al [ 2 , 3 ]. Removing a well-fixed, osseo-integrated cementless acetabular component during revision surgery can be challenging [ 2 , 4 – 6 ]. The surgeon must breakdown the bone-implant connection to loosen the implant [ 7 , 8 ]. However, this procedure is time-consuming and would pose the risk of significant bone loss or periacetabular fracture, which are closely associated with the complexity of acetabular reconstruction, suboptimal fixation of a new component and failure of acetabular fixation [ 9 ]. To avoid severe complications, some surgeons preserve the implant as a compromise [ 10 , 11 ], although it can increase the risk of failure for revision surgery [ 7 , 12 , 13 ]. Several strategies have been developed to facilitate the acetabular cup removal by using designed instruments. The most commonly used method involves identifying the bone-implant interface and using curved osteotomes to chip it away [ 14 ]. However, traditional osteotomes are relatively thick and can cause further damage to the residual bone bed or even fracture, especially in the posterolateral region of the acetabulum. Additionally, limited exposure to the inferior-medial part of the acetabula makes their usage challenging. The Explant Acetabular Cup Removal System (Zimmer, Warsaw, Indiana, USA) was designed to facilitate the removal of conventional modular acetabular cups, demonstrating much easier usage than traditional curved osteotomes [ 13 ]. However, this system is not always available because of a shortage of supplements. Moreover, an intact liner is primarily needed for instrument centralization during the procedure and can only accommodate standard femoral head sizes (22-, 28-, and 32-mm diameters). Although there are some other acetabular component removal systems, either manually or powered systems, the availability is always poor [ 15 ]. Driven by the clinical needs and the hemispherical shape of the acetabular cup, the author (Qing Jiang) developed a new strategy to remove a well-fixed cementless cup. This retrospective study aimed to introduce this technique and investigate its safety, efficiency, and clinical outcomes by comparing with the acetabular removal using the Explant Acetabular Cup Removal System. Methods Study design This retrospective study was approved by the Ethics Committee of our hospital (2024-997-02). Patients who underwent revision total hip arthroplasty in our center between 2019 and 2022 were reviewed, and those meeting the following criteria were recruited: (1) the acetabular cup was well-fixed and removed using our new technique or the Explant System; (2) reconstruction with a cementless cup, with or without augmentations; and (3) a minimum follow-up of 2 years. The exclusion criteria included (1) partial hip revision with the cup preserved; (2) cup removed using other methods, or both methods mentioned above were used; (3) pre-revision cup loosening; (4) significant osteolysis around the cup and an ingrowth area of < 50% [ 16 ]; (5) follow-up of less than 2 years, or loss to follow-up; and (6) cups with fins or spikes and threaded acetabular cups. These criteria allow assessment of the effect of the two techniques in removing well-fixed cementless acetabular components and the long-term outcomes after their implementation. Demographic data and reasons for revision were recorded. The reasons for revision included recurrent dislocation, infection, periprosthetic femoral fracture, impingement, and excessive polyethylene wear, for which no new polyethylene was available for revision. In cases of hip revisions caused by infection, single- or two-stage surgery was performed depending on the overall health and soft tissue conditions [ 17 ]. The osteolysis around the acetabular cup was evaluated using an anteroposterior and lateral view of the affected hip joint, and a computerized tomography (CT) scan if needed. The stability of the cups was assessed preoperatively according to the criteria of Udomkiat et al. [ 18 ] and confirmed intraoperatively. Bone defects were evaluated by removing the cup using our new strategy or the Explant System (ES), and bone grafting or metal augments were performed if necessary. The acetabular cups were reimplanted and reinforced with screws. During the revision procedure, the size of the removed acetabular component and the reimplanted cup were recorded. The following surrogates were used to assess bone defects: (1) the difference of OD between the removed acetabular component size and final reamer size; (2) the difference of OD between the removed acetabular component and the newly implanted one; and (3) the use of impaction bone grafting or metal augments [ 14 ]. Surgical technique of acetabular component removal The concept of our new strategy to remove a well-fixed acetabular component is to break the bond between the acetabulum and bone on the outer layer of the cup via vertical shear force (VSF). The VSF was generated by the impact on the ring of the acetabular component, then transmitted along the outer surface due to the hemispherical shape of the cup (Fig. 1 ). The ring of the acetabulum was completely exposed by removing scars and osteophytes. Liner and screws were then removed. A designed instrument (Fig. 2 ) was placed on the ring and inner layer of the cup (Fig. 3 ), then impacted by a hammer to generate a VSF on the ring. The impaction starts from the super-posterior and moves gradually to the anteroinferior of the ring for a cycle. Once the cup was loosened, it could be removed easily by rongeur (Fig. 4 ). In case of an ingrowth component or failure in mobilizing the cup by previous procedure, a thin chisel was applied to break the bone-acetabular interface to a depth of 5 mm around the ring. Then, the previous impaction procedure would be repeated again with moderate hammering force. If the cup can’t be mobilized, the Explant System (ES) would be employed to remove the cup. Postoperative review and recording of the acetabular cup removal time were conducted using the operating room video recording system. Acetabular reconstruction The bone bed was inspected, and the bone defect was assessed and documented according to the AAOS classification. Free hand reconstruction was carried out by reverse reaming based on the positions of the fossa acetabuli and transverse ligament. For contained bone defects that did not compromise stability, impaction bone grafting was performed, while metal augments were used for others. Follow-up Patients were regularly followed up at 6 weeks, 12 weeks, 6 months, and yearly through outpatient clinic visits and telephone interviews. All the patients were contacted to have a clinical visit follow-up according to our study design, if they didn’t have a follow-up record in the last year. The follow-up assessments included the stability and bio-growth of the acetabular component by X-ray film, and functional outcome by the Harris Hip Score. Complications were recorded, including dislocation, infection, and loosening of components. The patients were followed up for an average of 34 months (28–43 months) in the VSF group and 50 months (43–67 months) in the ES group. Statistical analysis Statistical analysis was performed using SPSS Statistics Package v.25 (IBM, Armonk, New York, USA). The chi-square test was employed to compare the differences in gender, preoperative diagnosis, acetabular defect, revision type, and the use of bone grafting or metal augments between the two groups of patients. The Mann-Whitney U test was used to compare the differences in patient age, duration of implantation, time to remove the acetabular cup, bone defect, the preoperative HHS, and the HHS at the final follow-up. A p value less than 0.05 was considered to indicate a statistically significant difference. Results Seventy patients (30 males, 40 females, average age: 70.1 years, range: 53–85 years) were enrolled in the study. The mean interval between initial and revision surgery was 9.8 years (range: 0–20 years). Indications for acetabular revision included periprosthetic joint infection in 37 cases, polyethylene wear and osteolysis in nineteen, recurrent dislocation due to poor acetabular component positioning in seven, periprosthetic femoral fracture in four, and impingement in three. There were 9 (13%) isolated acetabular revisions and 61 (87%) combined acetabular and femoral revisions. The majority of the hips had no preoperative acetabular bony defects (53 hips; 76%). Seventeen (24%) hips had cavitary defects (AAOS type II). Thirty-two (46%) acetabular components were removed with our new technique, whereas 38 (54%) were removed with the Explant System. Demographic data were summarized in Table 1 . Table 1 Comparative Patient Characteristics and Surgical Outcomes by Cup Removal Technique Variable VSF Group ES Group† p Patients, No. 32 38 Age (y) [mean (range)] 69.6 (53–82) 71.4 (63–85) 0.11 Sex, No. Male 15 15 0.08 Female 17 23 Preoperative diagnosis, No. Infection 16 21 0.35 Polyethylene wear 11 8 Recurrent dislocation 3 4 Periprosthetic femoral fracture 1 3 Impingement 1 2 Preoperative acetabular defect, No. None 24 29 0.32 AAOS type II 8 9 Duration of implantation (y) [median (range)] 9.4 (0–17) 10.1 (0–20) 0.63 Type of revision, No. Acetabular and femoral 28 33 0.33 Acetabular 4 5 † The Explant Acetabular Cup Removal System (Zimmer, Warsaw, Indiana, USA) Note All the operations were performed by a single experienced surgeon. AAOS: American Academy of Orthopaedic Surgeons. All the operations were performed by two experienced surgeons. There was no difference between the groups in terms of age (p = 0.11), gender ( p = 0.08), indications for revision ( p = 0.35), preoperative acetabular bone defect ( p = 0.32), revision type ( p = 0.33), reoperation rate during follow-up ( p = 1.00), the HHS before operation ( p = 0.53), and at the final follow-up ( p = 0.16). The VSF strategy was used in 34 patients, but failed in two patients, leaving thirty-two patients in the VSF group. Hence, the VSF strategy for removing a well-fixed cup had a success rate of 94.1%. In the other 38 patients, the acetabular cup was removed using the Explant system. The median and mean difference between the initial acetabular component size and final reamer size was 2.0 and 1.7 mm (range, 0–4 mm) in the VSF group and 3.0 and 3.2 mm (range, 0–7 mm) in the ES group ( p < 0.001) (Table 2 ). The median and mean change between initial and new acetabular component in the VSF group was 4.0 and 3.5 mm (range, 2–6 mm) and 4.0 and 4.7 mm (range, 2–8 mm) in the ES group ( p = .003) (Table 2 ). All hips were reconstructed with standard hemispherical acetabular components. Bone grafting or metal augments were used in 4 (13%) and 11(29%) patients in the VSF group and the ES group, respectively, with increased incidence in the ES group ( p = 0.03) (Table 2 ). Table 2 Operative Efficiency and Bone Preservation by Cup Removal Technique VSF Group ES Group† p Patients, No. 32 38 Acetabular cup removal time, (min) [median, mean (range)] 3.0 and 2.5 (1–6) 10.0 and 9.8 (7–16) <0.001 Difference of OD between removed acetabular component and final reamer,[median, mean (range)], mm 2.0 and 1.7 (0–4) 3.0 and 3.2 (0–7) <0.001 Difference of OD between removed and newly implanted acetabular component size (mm) [median, mean (range)] 4.0 and 3.5 (2–6) 4.0 and 4.7 (2–8) 0.003 Bone grafting or metal augments required (%). 4 (13%) 11 (29%) 0.03 Preoperative HHS (points) [mean ± SD] 33.7 ± 14.5 31.8 ± 10.6 0.53 Final follow-up HHS (points) [mean ± SD] 78.6 ± 5.4 80.8 ± 7.2 0.16 Pre- vs. postoperative HHS comparison ( p -value) <0.001 <0.001 † The Explant Acetabular Cup Removal System (Zimmer, Warsaw, Indiana, USA) Note All the operations were performed by a single experienced surgeon. HHS: Harris Hip Score. Patients were followed up for an average of 34 months (28–43 months) in the VSF group and 50 months (43–67 months) in the ES group, and none of them required re-revision because of acetabular component loosening. The mean Harris Hip Score (HHS) improved from 33.7 ± 14.5 preoperatively to 78.6 ± 5.4 ( p < 0.001) at final follow-up in the VSF group, and from 31.8 ± 10.6 points to 80.8 ± 7.2 (p < 0.001) in the ES group, respectively. Deep vein thrombosis (DVT) of the lower extremity occurred in three patients each in both the VSF and ES groups postoperatively; all cases were resolved with pharmacological treatment. There was no significant acetabular fracture caused by implant removal in either group. There was no intraoperative acetabular fracture, dislocation, acetabular component loosening, or infection, and none of the patients required re-revision during follow-up. Discussion Removing a well-fixed acetabular cup in revision arthroplasty is always challenging. It’s not only a time-consuming procedure, but also has an increased risk of complications if not handled properly, such as significant bone defects or even iatrogenic acetabular fractures. Our novel strategy involves breaking the bone growth by a vertical shear force along the outer layer of the cup, without causing iatrogenic injury to the acetabulum. Results of the current retrospective analysis showed that this strategy effectively removed a well-fixed cup with a success rate of 94.1%, causing reduced bone defect, presenting as the cup size increased by an average of 1.7 mm. Importantly, even when unsuccessful, the technique does not compromise acetabular integrity. Over the past few decades, several types of equipment and surgical techniques have been developed to facilitate cup removal. These methods can be classified into two groups: mechanical cutting and force transduction. The former uses osteotomes to create a gap between the bone and the prosthesis interface, typically represented by traditional curved osteotomes, also called Aufranc acetabular gouges [ 7 , 19 ]. Other equipment and techniques include the use of a pneumatic impact wrench [ 20 ] or a reciprocating saw [ 21 ]. However, these methods may cause significant bone defects and increase the need for bone grafting. The Zimmer Explant System has been developed using relatively thin, curved blades to minimize the incidence of bone defect [ 14 ]. However, limitations of the Explant System can’t be overlooked, such as the requirement for an intact liner, and cannot be applied to all femoral head sizes [ 13 ] Several methods have been proposed to address these limitations [ 1 , 22 , 24 ]. Kwong et al . [ 25 ] invented the Stryker EZout Powered Acetabular Revision System, an electric Explant System designed to improve accuracy and reduce physical strain. However, neither the Zimmer Explant System nor the electric Explant System is always available in most medical centers. The latter uses force conduction to separate the prosthesis from the host bone. Daum et al. [ 26 ] were the first to describe a technique based on this principle. Using a rongeur, they exposed a spot approximately 3–4 mm in diameter over the superolateral margin of the prosthesis and then used an offset punch and applied force in an inferior direction with a mallet. The research team observed an increased risk of acetabular fractures by using this method, possibly due to the force transmitted to the contralateral acetabular wall. Zhang et al . [ 27 ] reported a technique that involves drilling a tunnel on the superolateral rim of the acetabulum and using an offset staff to punch perpendicular to the cup. Despite a simple procedure and bone stock-preserving technique, additional exposure on the superolateral acetabulumis required for drilling procedures, which would increase the incidence of neurovascular injury. Date comparison of common acetabular removal techniques and our technique are summarized in Table 3 . The VSF technique showed better results in bone preservation during acetabular cup removal compared to other methods, evidenced by a smaller difference of OD between the removed acetabular component and final reamer, as well as a lower number of cases requiring bone grafting or metal augments. Table 3 Comparison of common acetabular removal techniques and our technique Author Mitchell 13 Preiss 24 Adelani 14 Adelani 14 Qing Jiang Qing Jiang Technique/Tools Zimmer Explant System Zimmer Explant System with modular femoral head Zimmer Explant System Aufranc Vertical Shear Force Zimmer Explant System Number of cases 31 15 27 24 32 38 Mean age (yrs) 65.2 (49–86) 54.0 (43–63) 67.9 (49–82) 62.2 (28–88) 69.6 (53–82) 71.4 (63–85) Sex 15 male 8 male 7 male 11 male 15 male 15 male 16 female 7 female 20 female 13 female 17 female 23 female Mean duration of implantation (yrs) 6.7 (1–11) 2.8 (1–5) 6.5 (0.5–17) 8.6 (0.5–21) 9.4 (0–17) 10.1 (0–20) Difference of OD between the removed acetabular component and final reamer, median and mean (range), mm 4.0 and 3.7 (0–10) 0 and 1.2 (0–6) 3.0 and – (0–8) 5.0 and – (0–10) 2.0 and 1.7(0–4) 3.0 and 3.2(0–7) Intraoperative complications Nil Nil 7 bone grafting 13 bone grafting 4 metal augments 11 metal augments Postoperative complications - 1 early dislocation - - 3 DVT 3 DVT Note. - means not reported. We found that well-fixed cups could be removed effectively by the new technique with no related complications during the 2-year follow-up. Patients treated with the new technique showed comparable joint function restoration to those treated with the Explant System. When using the new revision technique, the differences between the outer diameter of the initial acetabular components and both the final reamer diameter and new component diameter were minimal. These smaller differences indicated better bone preservation compared to cases using the traditional Explant System. Additionally, reconstruction with the Explant System required metal augments significantly more often than the other group. For cases requiring supplemental support (15/15) metal augments were selected exclusively due to their cost-effectiveness. This preference is supported by previous studies showing metal augments provide outcomes comparable to other reconstruction methods for severe acetabular bone loss, with excellent survivorship at a mean 6.6-year follow-up [ 28 ]. Our new technique offers several distinct advantages. First, the single-component instrument design provides straightforward handling and can be adjusted to accommodate various prosthetic sizes. This adaptability eliminates the need for precise preoperative specifications of acetabular component dimensions, which may reduce both operative time and blood loss. In hip revision surgery, this undoubtedly implies a reduction in the incidence of postoperative complications and infections [ 29 , 30 ]. Secondly, the instrument is cost-effective, priced at approximately $ 100–200 per unit. This represents a substantial economic advantage compared to the Explant System, which incorporates complex components and carries a significantly higher cost (typically tens of thousands of dollars). This study has some limitations. Firstly, our technique is suitable for hemispherical or elliptical acetabular components; however, it can be difficult to remove cups with fins and spikes, and it cannot be used to remove threaded acetabular cups. Moreover, the retrospective nature of this study necessitates further validation through randomized controlled trials. Nevertheless, there was a certain discrepancy in the follow-up time between the two groups of patients due to the different sequences of surgeries, which may have a potential influence on the follow-up outcomes. Conclusion The vertical striking technique offers a simple, reproducible, cost-effective, and safe approach for acetabular cup removal. It preserves acetabular bone stock and minimizes complication risks. The specially designed instrument can reduce the risk of iatrogenic bone injury. The revised acetabular prostheses using our technique showed favorable midterm results, with effective restoration of hip joint function. Abbreviations VSF vertical shear force ES the Explant System HHS Harris Hip Scores Declarations Ethics approval and consent to participate This retrospective study was reviewed and approved by the Ethics Committee of of Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School (Approval No. 2025037102), and all study participants provided informed consent. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and National Research Committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Consent for publication Not applicable. Clinical trial number Not applicable. Competing interests The authors declare that they have no competing interests. Funding No funding was received. Author Contribution QJ and WJW designed the study and contributed to draft writing. MHZ, YTY, and SGL contributed to data collection. MHZ and YTY contributed to statistical analysis. MHZ and WJW was involved in writing the manuscript. QJ and WJW was the research supervisor. All authors read and approved the final manuscript. Acknowledgements This work was supported by the National Major Research Plan of NSFC (92368201), National Key Research and Development Project (2021YFA1201404). Data Availability The data used to support the findings of this study are available in the text and can be procured from the corresponding author upon request. References Shichman I, Roof M, Askew N, et al. Projections and Epidemiology of Primary Hip and Knee Arthroplasty in Medicare Patients to 2040–2060. JBJS Open Access. 2023;8(1):e2200112. Olyslaegers C, Wainwright T, Middleton RG. 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Cite Share Download PDF Status: Published Journal Publication published 07 Feb, 2026 Read the published version in BMC Musculoskeletal Disorders → Version 1 posted Editorial decision: Revision requested 10 Dec, 2025 Reviews received at journal 04 Dec, 2025 Reviews received at journal 01 Dec, 2025 Reviews received at journal 19 Nov, 2025 Reviews received at journal 18 Nov, 2025 Reviewers agreed at journal 18 Nov, 2025 Reviewers agreed at journal 17 Nov, 2025 Reviewers agreed at journal 12 Nov, 2025 Reviewers agreed at journal 12 Nov, 2025 Reviewers agreed at journal 11 Nov, 2025 Reviewers agreed at journal 11 Nov, 2025 Reviewers invited by journal 09 Nov, 2025 Editor invited by journal 07 Nov, 2025 Editor assigned by journal 15 Oct, 2025 Submission checks completed at journal 13 Oct, 2025 First submitted to journal 13 Oct, 2025 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. 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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-7773136","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":546998956,"identity":"b31e622a-5eee-4e91-99e4-3ca09d2534ed","order_by":0,"name":"Minghao Zhang","email":"","orcid":"","institution":"Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","correspondingAuthor":false,"prefix":"","firstName":"Minghao","middleName":"","lastName":"Zhang","suffix":""},{"id":546998957,"identity":"5e307c2f-8596-46d4-9540-6139d4305c78","order_by":1,"name":"Yutao Yang","email":"","orcid":"","institution":"Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","correspondingAuthor":false,"prefix":"","firstName":"Yutao","middleName":"","lastName":"Yang","suffix":""},{"id":546998958,"identity":"01440846-35cd-4eef-b4b2-1918efee844d","order_by":2,"name":"Shiguang Lai","email":"","orcid":"","institution":"Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","correspondingAuthor":false,"prefix":"","firstName":"Shiguang","middleName":"","lastName":"Lai","suffix":""},{"id":546998959,"identity":"87b0a2bd-f108-4d28-82ae-7c06b137d10c","order_by":3,"name":"Weijun Wang","email":"","orcid":"","institution":"Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","correspondingAuthor":false,"prefix":"","firstName":"Weijun","middleName":"","lastName":"Wang","suffix":""},{"id":546998960,"identity":"f34f0187-24c8-43bc-b00a-57e832cbe965","order_by":4,"name":"Qing Jiang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAvUlEQVRIiWNgGAWjYDACZiCWqABTDBIkaDlDkhYQYGyD0MRp4TvOe/iF5bw77AYHmA/e5mGwyyOoRfIwX5qF5LZnzAYH2JKteRiSiwlqMTjMY2Ygue0wUAuPmTQPw4HEBuK0zAFp4f9GtBbjB5INYFvYiNMiCbSFQeLYYWbJw2zGlnMMkglr4Tt/xvizRM3hZL7jzQ9vvKmwI6yF4QADmzQwPpIhkWlAUD1YC/PHDwwMdsSoHQWjYBSMghEKAE/VNw7hUoq0AAAAAElFTkSuQmCC","orcid":"","institution":"Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","correspondingAuthor":true,"prefix":"","firstName":"Qing","middleName":"","lastName":"Jiang","suffix":""}],"badges":[],"createdAt":"2025-10-03 11:38:22","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7773136/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7773136/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12891-026-09581-8","type":"published","date":"2026-02-07T15:59:07+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":96330110,"identity":"906a2d94-5c3a-4b2f-9b09-b2055eeffdec","added_by":"auto","created_at":"2025-11-20 00:46:18","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1764098,"visible":true,"origin":"","legend":"","description":"","filename":"Thesafetyandefficiencyofanewstrategytoremovethewellfixedcementlessacetabularcomponentsinrevisionhiparthroplastyaretrospectivecomparativestudy.docx","url":"https://assets-eu.researchsquare.com/files/rs-7773136/v1/9c451dd323da214723e62005.docx"},{"id":96330108,"identity":"9feace95-d039-47c6-b2af-f5f62de4830c","added_by":"auto","created_at":"2025-11-20 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00:46:19","extension":"xml","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":88312,"visible":true,"origin":"","legend":"","description":"","filename":"89289d4fd49f4ab8a40e9cbf41bc86341structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7773136/v1/e0076fc0fbe22dee01005729.xml"},{"id":96330117,"identity":"1deec977-8e09-4b10-8a77-f5bdd92ca67c","added_by":"auto","created_at":"2025-11-20 00:46:19","extension":"html","order_by":12,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":96671,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7773136/v1/260a4340795d88d5cbba47d7.html"},{"id":96366932,"identity":"f8b15361-340b-4272-af32-50dfcdb88819","added_by":"auto","created_at":"2025-11-20 10:12:02","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":41885,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of the conduction of vertical forces acting on an acetabular prosthesis (The blue arc represents the acetabular prosthesis cross-section, the green arrows represent the direction in which the force is conducted, and the purple arrows represent the direction in which the force can be applied)\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7773136/v1/d97f0d41b9a85e06cbdf234d.png"},{"id":96330111,"identity":"38de301b-c6b6-4009-87c7-21f621f7d283","added_by":"auto","created_at":"2025-11-20 00:46:18","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":463781,"visible":true,"origin":"","legend":"\u003cp\u003eOur\u003cstrong\u003e \u003c/strong\u003especially designed instrument\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7773136/v1/9d970fc02f1c2297377ff6cc.jpeg"},{"id":96330119,"identity":"3fc0d30c-c12e-4479-ad7d-323c160d8e6e","added_by":"auto","created_at":"2025-11-20 00:46:19","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":60082,"visible":true,"origin":"","legend":"\u003cp\u003eDesigned instrument was placed on the ring and inner layer of the cup\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7773136/v1/42f64a991a76895c97b1ffa8.jpeg"},{"id":96330115,"identity":"d3a78993-6530-4de2-bb5c-09565718f362","added_by":"auto","created_at":"2025-11-20 00:46:19","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":1556555,"visible":true,"origin":"","legend":"\u003cp\u003eAcetabular prostheses removed with our technique and instrument\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-7773136/v1/9ff99db721a010afcd79c4de.png"},{"id":102234367,"identity":"c7b49c81-8658-4f18-b36d-8a59799f5b7c","added_by":"auto","created_at":"2026-02-09 16:10:32","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3216191,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7773136/v1/d11832a5-236d-4204-a956-9ce6b9df8ecb.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The safety and efficiency of a new strategy to remove the well-fixed cementless acetabular components in revision hip arthroplasty: a retrospective comparative study","fulltext":[{"header":"Background","content":"\u003cp\u003eThe volume of revision hip arthroplasty has kept increasing in the last decade, with over 36,000 procedures expected to be performed in the United States by 2030 [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Revision surgeries involve removing failed implants and reconstructing the hip with new ones, where a well-fixed acetabular cup is generally preserved to minimize the damage and simplify the surgery. However, removal of a well-fixed implant is necessary in certain scenarios - such as periprosthetic joint infection, recurrent dislocation due to malposition of the implant, impingement, broken locking mechanism, or the desired liner type is unavailable \u003cem\u003eet al\u003c/em\u003e [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eRemoving a well-fixed, osseo-integrated cementless acetabular component during revision surgery can be challenging [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. The surgeon must breakdown the bone-implant connection to loosen the implant [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. However, this procedure is time-consuming and would pose the risk of significant bone loss or periacetabular fracture, which are closely associated with the complexity of acetabular reconstruction, suboptimal fixation of a new component and failure of acetabular fixation [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. To avoid severe complications, some surgeons preserve the implant as a compromise [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], although it can increase the risk of failure for revision surgery [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eSeveral strategies have been developed to facilitate the acetabular cup removal by using designed instruments. The most commonly used method involves identifying the bone-implant interface and using curved osteotomes to chip it away [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. However, traditional osteotomes are relatively thick and can cause further damage to the residual bone bed or even fracture, especially in the posterolateral region of the acetabulum. Additionally, limited exposure to the inferior-medial part of the acetabula makes their usage challenging. The Explant Acetabular Cup Removal System (Zimmer, Warsaw, Indiana, USA) was designed to facilitate the removal of conventional modular acetabular cups, demonstrating much easier usage than traditional curved osteotomes [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. However, this system is not always available because of a shortage of supplements. Moreover, an intact liner is primarily needed for instrument centralization during the procedure and can only accommodate standard femoral head sizes (22-, 28-, and 32-mm diameters). Although there are some other acetabular component removal systems, either manually or powered systems, the availability is always poor [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eDriven by the clinical needs and the hemispherical shape of the acetabular cup, the author (Qing Jiang) developed a new strategy to remove a well-fixed cementless cup. This retrospective study aimed to introduce this technique and investigate its safety, efficiency, and clinical outcomes by comparing with the acetabular removal using the Explant Acetabular Cup Removal System.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStudy design\u003c/h2\u003e\u003cp\u003e This retrospective study was approved by the Ethics Committee of our hospital (2024-997-02). Patients who underwent revision total hip arthroplasty in our center between 2019 and 2022 were reviewed, and those meeting the following criteria were recruited: (1) the acetabular cup was well-fixed and removed using our new technique or the Explant System; (2) reconstruction with a cementless cup, with or without augmentations; and (3) a minimum follow-up of 2 years. The exclusion criteria included (1) partial hip revision with the cup preserved; (2) cup removed using other methods, or both methods mentioned above were used; (3) pre-revision cup loosening; (4) significant osteolysis around the cup and an ingrowth area of \u0026lt;\u0026thinsp;50% [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]; (5) follow-up of less than 2 years, or loss to follow-up; and (6) cups with fins or spikes and threaded acetabular cups. These criteria allow assessment of the effect of the two techniques in removing well-fixed cementless acetabular components and the long-term outcomes after their implementation.\u003c/p\u003e\u003cp\u003eDemographic data and reasons for revision were recorded. The reasons for revision included recurrent dislocation, infection, periprosthetic femoral fracture, impingement, and excessive polyethylene wear, for which no new polyethylene was available for revision. In cases of hip revisions caused by infection, single- or two-stage surgery was performed depending on the overall health and soft tissue conditions [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. The osteolysis around the acetabular cup was evaluated using an anteroposterior and lateral view of the affected hip joint, and a computerized tomography (CT) scan if needed. The stability of the cups was assessed preoperatively according to the criteria of Udomkiat et al. [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] and confirmed intraoperatively.\u003c/p\u003e\u003cp\u003eBone defects were evaluated by removing the cup using our new strategy or the Explant System (ES), and bone grafting or metal augments were performed if necessary. The acetabular cups were reimplanted and reinforced with screws. During the revision procedure, the size of the removed acetabular component and the reimplanted cup were recorded. The following surrogates were used to assess bone defects: (1) the difference of OD between the removed acetabular component size and final reamer size; (2) the difference of OD between the removed acetabular component and the newly implanted one; and (3) the use of impaction bone grafting or metal augments [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eSurgical technique of acetabular component removal\u003c/h3\u003e\n\u003cp\u003eThe concept of our new strategy to remove a well-fixed acetabular component is to break the bond between the acetabulum and bone on the outer layer of the cup via vertical shear force (VSF). The VSF was generated by the impact on the ring of the acetabular component, then transmitted along the outer surface due to the hemispherical shape of the cup (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe ring of the acetabulum was completely exposed by removing scars and osteophytes. Liner and screws were then removed. A designed instrument (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) was placed on the ring and inner layer of the cup (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), then impacted by a hammer to generate a VSF on the ring. The impaction starts from the super-posterior and moves gradually to the anteroinferior of the ring for a cycle. Once the cup was loosened, it could be removed easily by rongeur (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eIn case of an ingrowth component or failure in mobilizing the cup by previous procedure, a thin chisel was applied to break the bone-acetabular interface to a depth of 5 mm around the ring. Then, the previous impaction procedure would be repeated again with moderate hammering force. If the cup can\u0026rsquo;t be mobilized, the Explant System (ES) would be employed to remove the cup. Postoperative review and recording of the acetabular cup removal time were conducted using the operating room video recording system.\u003c/p\u003e\n\u003ch3\u003eAcetabular reconstruction\u003c/h3\u003e\n\u003cp\u003eThe bone bed was inspected, and the bone defect was assessed and documented according to the AAOS classification. Free hand reconstruction was carried out by reverse reaming based on the positions of the fossa acetabuli and transverse ligament. For contained bone defects that did not compromise stability, impaction bone grafting was performed, while metal augments were used for others.\u003c/p\u003e\n\u003ch3\u003eFollow-up\u003c/h3\u003e\n\u003cp\u003ePatients were regularly followed up at 6 weeks, 12 weeks, 6 months, and yearly through outpatient clinic visits and telephone interviews. All the patients were contacted to have a clinical visit follow-up according to our study design, if they didn\u0026rsquo;t have a follow-up record in the last year. The follow-up assessments included the stability and bio-growth of the acetabular component by X-ray film, and functional outcome by the Harris Hip Score. Complications were recorded, including dislocation, infection, and loosening of components. The patients were followed up for an average of 34 months (28\u0026ndash;43 months) in the VSF group and 50 months (43\u0026ndash;67 months) in the ES group.\u003c/p\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eStatistical analysis was performed using SPSS Statistics Package v.25 (IBM, Armonk, New York, USA). The chi-square test was employed to compare the differences in gender, preoperative diagnosis, acetabular defect, revision type, and the use of bone grafting or metal augments between the two groups of patients. The Mann-Whitney U test was used to compare the differences in patient age, duration of implantation, time to remove the acetabular cup, bone defect, the preoperative HHS, and the HHS at the final follow-up. A \u003cem\u003ep\u003c/em\u003e value less than 0.05 was considered to indicate a statistically significant difference.\u003c/p\u003e\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eSeventy patients (30 males, 40 females, average age: 70.1 years, range: 53\u0026ndash;85 years) were enrolled in the study. The mean interval between initial and revision surgery was 9.8 years (range: 0\u0026ndash;20 years). Indications for acetabular revision included periprosthetic joint infection in 37 cases, polyethylene wear and osteolysis in nineteen, recurrent dislocation due to poor acetabular component positioning in seven, periprosthetic femoral fracture in four, and impingement in three. There were 9 (13%) isolated acetabular revisions and 61 (87%) combined acetabular and femoral revisions. The majority of the hips had no preoperative acetabular bony defects (53 hips; 76%). Seventeen (24%) hips had cavitary defects (AAOS type II). Thirty-two (46%) acetabular components were removed with our new technique, whereas 38 (54%) were removed with the Explant System. Demographic data were summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\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\u003eComparative Patient Characteristics and Surgical Outcomes by Cup Removal Technique\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\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\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\u003eVSF Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eES Group\u0026dagger;\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePatients, No.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge (y) [mean (range)]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e69.6 (53\u0026ndash;82)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e71.4 (63\u0026ndash;85)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.11\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex, No.\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=\"left\" colname=\"c4\"\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\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.08\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\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePreoperative diagnosis, No.\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=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eInfection\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"4\" rowspan=\"5\"\u003e\u003cp\u003e0.35\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePolyethylene wear\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRecurrent dislocation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePeriprosthetic femoral fracture\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eImpingement\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePreoperative acetabular defect, No.\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=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNone\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.32\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAAOS type II\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDuration of implantation (y) [median (range)]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9.4 (0\u0026ndash;17)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e10.1 (0\u0026ndash;20)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.63\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eType of revision, No.\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=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAcetabular and femoral\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.33\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAcetabular\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5\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\u0026dagger; The Explant Acetabular Cup Removal System (Zimmer, Warsaw, Indiana, USA)\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eNote\u003c/strong\u003e\u003cp\u003eAll the operations were performed by a single experienced surgeon. AAOS: American Academy of Orthopaedic Surgeons.\u003c/p\u003e\u003c/p\u003e\u003cp\u003eAll the operations were performed by two experienced surgeons. There was no difference between the groups in terms of age \u003cem\u003e(p\u0026thinsp;=\u003c/em\u003e\u0026thinsp;0.11), gender (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.08), indications for revision (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.35), preoperative acetabular bone defect (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.32), revision type (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.33), reoperation rate during follow-up (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.00), the HHS before operation (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.53), and at the final follow-up (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.16). The VSF strategy was used in 34 patients, but failed in two patients, leaving thirty-two patients in the VSF group. Hence, the VSF strategy for removing a well-fixed cup had a success rate of 94.1%. In the other 38 patients, the acetabular cup was removed using the Explant system.\u003c/p\u003e\u003cp\u003eThe median and mean difference between the initial acetabular component size and final reamer size was 2.0 and 1.7 mm (range, 0\u0026ndash;4 mm) in the VSF group and 3.0 and 3.2 mm (range, 0\u0026ndash;7 mm) in the ES group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The median and mean change between initial and new acetabular component in the VSF group was 4.0 and 3.5 mm (range, 2\u0026ndash;6 mm) and 4.0 and 4.7 mm (range, 2\u0026ndash;8 mm) in the ES group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.003) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). All hips were reconstructed with standard hemispherical acetabular components. Bone grafting or metal augments were used in 4 (13%) and 11(29%) patients in the VSF group and the ES group, respectively, with increased incidence in the ES group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.03) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\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\u003eOperative Efficiency and Bone Preservation by Cup Removal Technique\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eVSF Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eES Group\u0026dagger;\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePatients, No.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAcetabular cup removal time, (min) [median, mean (range)]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3.0 and 2.5 (1\u0026ndash;6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e10.0 and 9.8 (7\u0026ndash;16)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDifference of OD between removed acetabular component and final reamer,[median, mean (range)], mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.0 and 1.7 (0\u0026ndash;4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.0 and 3.2 (0\u0026ndash;7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDifference of OD between removed and newly implanted acetabular component size (mm) [median, mean (range)]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4.0 and 3.5 (2\u0026ndash;6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4.0 and 4.7 (2\u0026ndash;8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBone grafting or metal augments required (%).\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4 (13%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e11 (29%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.03\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePreoperative HHS (points) [mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e33.7\u0026thinsp;\u0026plusmn;\u0026thinsp;14.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e31.8\u0026thinsp;\u0026plusmn;\u0026thinsp;10.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.53\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFinal follow-up HHS (points) [mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e78.6\u0026thinsp;\u0026plusmn;\u0026thinsp;5.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e80.8\u0026thinsp;\u0026plusmn;\u0026thinsp;7.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.16\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePre- vs. postoperative HHS comparison (\u003cem\u003ep\u003c/em\u003e-value)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026lt;0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026lt;0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\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\u0026dagger; The Explant Acetabular Cup Removal System (Zimmer, Warsaw, Indiana, USA)\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eNote\u003c/strong\u003e\u003cp\u003eAll the operations were performed by a single experienced surgeon. HHS: Harris Hip Score.\u003c/p\u003e\u003c/p\u003e\u003cp\u003ePatients were followed up for an average of 34 months (28\u0026ndash;43 months) in the VSF group and 50 months (43\u0026ndash;67 months) in the ES group, and none of them required re-revision because of acetabular component loosening. The mean Harris Hip Score (HHS) improved from 33.7\u0026thinsp;\u0026plusmn;\u0026thinsp;14.5 preoperatively to 78.6\u0026thinsp;\u0026plusmn;\u0026thinsp;5.4 (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) at final follow-up in the VSF group, and from 31.8\u0026thinsp;\u0026plusmn;\u0026thinsp;10.6 points to 80.8\u0026thinsp;\u0026plusmn;\u0026thinsp;7.2 \u003cem\u003e(p\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) in the ES group, respectively. Deep vein thrombosis (DVT) of the lower extremity occurred in three patients each in both the VSF and ES groups postoperatively; all cases were resolved with pharmacological treatment. There was no significant acetabular fracture caused by implant removal in either group. There was no intraoperative acetabular fracture, dislocation, acetabular component loosening, or infection, and none of the patients required re-revision during follow-up.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eRemoving a well-fixed acetabular cup in revision arthroplasty is always challenging. It\u0026rsquo;s not only a time-consuming procedure, but also has an increased risk of complications if not handled properly, such as significant bone defects or even iatrogenic acetabular fractures. Our novel strategy involves breaking the bone growth by a vertical shear force along the outer layer of the cup, without causing iatrogenic injury to the acetabulum. Results of the current retrospective analysis showed that this strategy effectively removed a well-fixed cup with a success rate of 94.1%, causing reduced bone defect, presenting as the cup size increased by an average of 1.7 mm. Importantly, even when unsuccessful, the technique does not compromise acetabular integrity.\u003c/p\u003e\u003cp\u003eOver the past few decades, several types of equipment and surgical techniques have been developed to facilitate cup removal. These methods can be classified into two groups: mechanical cutting and force transduction. The former uses osteotomes to create a gap between the bone and the prosthesis interface, typically represented by traditional curved osteotomes, also called Aufranc acetabular gouges [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Other equipment and techniques include the use of a pneumatic impact wrench [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] or a reciprocating saw [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. However, these methods may cause significant bone defects and increase the need for bone grafting. The Zimmer Explant System has been developed using relatively thin, curved blades to minimize the incidence of bone defect [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. However, limitations of the Explant System can\u0026rsquo;t be overlooked, such as the requirement for an intact liner, and cannot be applied to all femoral head sizes [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] Several methods have been proposed to address these limitations [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Kwong \u003cem\u003eet al\u003c/em\u003e. [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e] invented the Stryker EZout Powered Acetabular Revision System, an electric Explant System designed to improve accuracy and reduce physical strain. However, neither the Zimmer Explant System nor the electric Explant System is always available in most medical centers.\u003c/p\u003e\u003cp\u003eThe latter uses force conduction to separate the prosthesis from the host bone. Daum \u003cem\u003eet al.\u003c/em\u003e [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e] were the first to describe a technique based on this principle. Using a rongeur, they exposed a spot approximately 3\u0026ndash;4 mm in diameter over the superolateral margin of the prosthesis and then used an offset punch and applied force in an inferior direction with a mallet. The research team observed an increased risk of acetabular fractures by using this method, possibly due to the force transmitted to the contralateral acetabular wall. Zhang \u003cem\u003eet al\u003c/em\u003e. [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] reported a technique that involves drilling a tunnel on the superolateral rim of the acetabulum and using an offset staff to punch perpendicular to the cup. Despite a simple procedure and bone stock-preserving technique, additional exposure on the superolateral acetabulumis required for drilling procedures, which would increase the incidence of neurovascular injury. Date comparison of common acetabular removal techniques and our technique are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. The VSF technique showed better results in bone preservation during acetabular cup removal compared to other methods, evidenced by a smaller difference of OD between the removed acetabular component and final reamer, as well as a lower number of cases requiring bone grafting or metal augments.\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\u003eComparison of common acetabular removal techniques and our technique\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\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=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAuthor\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMitchell\u003csup\u003e13\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePreiss \u003csup\u003e24\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAdelani\u003csup\u003e14\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eAdelani\u003csup\u003e14\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eQing Jiang\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eQing Jiang\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTechnique/Tools\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eZimmer Explant System\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eZimmer Explant System with modular femoral head\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eZimmer Explant System\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eAufranc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eVertical Shear Force\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eZimmer Explant System\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNumber of cases\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e38\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMean age (yrs)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e65.2 (49\u0026ndash;86)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e54.0 (43\u0026ndash;63)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e67.9 (49\u0026ndash;82)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e62.2 (28\u0026ndash;88)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e69.6\u003c/p\u003e\u003cp\u003e(53\u0026ndash;82)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e71.4 (63\u0026ndash;85)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eSex\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e15 male\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8 male\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7 male\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e11 male\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e15 male\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e15 male\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e16 female\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7 female\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e20 female\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e13 female\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e17 female\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e23 female\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMean duration of implantation (yrs)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.7 (1\u0026ndash;11)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.8 (1\u0026ndash;5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6.5 (0.5\u0026ndash;17)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e8.6 (0.5\u0026ndash;21)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e9.4 (0\u0026ndash;17)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e10.1 (0\u0026ndash;20)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDifference of OD between the removed acetabular component and final reamer, median and mean (range), mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4.0 and 3.7 (0\u0026ndash;10)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0 and 1.2 (0\u0026ndash;6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3.0 and \u0026ndash; (0\u0026ndash;8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e5.0 and \u0026ndash; (0\u0026ndash;10)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2.0 and 1.7(0\u0026ndash;4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e3.0 and 3.2(0\u0026ndash;7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIntraoperative complications\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNil\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNil\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7 bone grafting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e13 bone grafting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4 metal augments\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e11 metal augments\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePostoperative complications\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1 early dislocation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3 DVT\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e3 DVT\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"7\"\u003eNote. - means not reported.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eWe found that well-fixed cups could be removed effectively by the new technique with no related complications during the 2-year follow-up. Patients treated with the new technique showed comparable joint function restoration to those treated with the Explant System. When using the new revision technique, the differences between the outer diameter of the initial acetabular components and both the final reamer diameter and new component diameter were minimal. These smaller differences indicated better bone preservation compared to cases using the traditional Explant System. Additionally, reconstruction with the Explant System required metal augments significantly more often than the other group. For cases requiring supplemental support (15/15) metal augments were selected exclusively due to their cost-effectiveness. This preference is supported by previous studies showing metal augments provide outcomes comparable to other reconstruction methods for severe acetabular bone loss, with excellent survivorship at a mean 6.6-year follow-up [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eOur new technique offers several distinct advantages. First, the single-component instrument design provides straightforward handling and can be adjusted to accommodate various prosthetic sizes. This adaptability eliminates the need for precise preoperative specifications of acetabular component dimensions, which may reduce both operative time and blood loss. In hip revision surgery, this undoubtedly implies a reduction in the incidence of postoperative complications and infections [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Secondly, the instrument is cost-effective, priced at approximately \u003cspan\u003e$\u003c/span\u003e100\u0026ndash;200 per unit. This represents a substantial economic advantage compared to the Explant System, which incorporates complex components and carries a significantly higher cost (typically tens of thousands of dollars).\u003c/p\u003e\u003cp\u003eThis study has some limitations. Firstly, our technique is suitable for hemispherical or elliptical acetabular components; however, it can be difficult to remove cups with fins and spikes, and it cannot be used to remove threaded acetabular cups. Moreover, the retrospective nature of this study necessitates further validation through randomized controlled trials. Nevertheless, there was a certain discrepancy in the follow-up time between the two groups of patients due to the different sequences of surgeries, which may have a potential influence on the follow-up outcomes.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe vertical striking technique offers a simple, reproducible, cost-effective, and safe approach for acetabular cup removal. It preserves acetabular bone stock and minimizes complication risks. The specially designed instrument can reduce the risk of iatrogenic bone injury. The revised acetabular prostheses using our technique showed favorable midterm results, with effective restoration of hip joint function.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eVSF\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003evertical shear force\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eES\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003ethe Explant System\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eHHS\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eHarris Hip Scores\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003cp\u003e This retrospective study was reviewed and approved by the Ethics Committee of of Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School (Approval No. 2025037102), and all study participants provided informed consent. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and National Research Committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003cp\u003eNot applicable.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003ch2\u003eClinical trial number\u003c/h2\u003e\u003cp\u003eNot applicable.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003ch2\u003eCompeting interests\u003c/h2\u003e\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e\u003cp\u003eNo funding was received.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eQJ and WJW designed the study and contributed to draft writing. MHZ, YTY, and SGL contributed to data collection. MHZ and YTY contributed to statistical analysis. MHZ and WJW was involved in writing the manuscript. QJ and WJW was the research supervisor. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e\u003cp\u003eThis work was supported by the National Major Research Plan of NSFC (92368201), National Key Research and Development Project (2021YFA1201404).\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe data used to support the findings of this study are available in the text and can be procured from the corresponding author upon request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eShichman I, Roof M, Askew N, et al. Projections and Epidemiology of Primary Hip and Knee Arthroplasty in Medicare Patients to 2040\u0026ndash;2060. JBJS Open Access. 2023;8(1):e2200112.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOlyslaegers C, Wainwright T, Middleton RG. A novel technique for the removal of well-fixed cementless, large-diameter metal-on-metal acetabular components. J Arthroplasty. 2008;23(7):1071\u0026ndash;3.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCho K, Park CW, Jeong SJ, et al. Long-Term Outcomes of Cementing Highly Cross-Linked Polyethylene Liners Into Well-Fixed Acetabular Shells in Revision Total Hip Arthroplasty. J Arthroplasty. 2023;38(7):1335\u0026ndash;41.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChen W, Klemt C, Padmanabha A, Tirumala V, Xiong L, Kwon YM. Outcome and Risk Factors Associated with Failures of Isolated Bearing Exchange for Osteolysis in Well-Fixed Cementless Total Hip Arthroplasty. J Arthroplasty. 2021;36(1):255\u0026ndash;60.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePeters CL, Kull L, Jacobs JJ, et al. The fate of well fixed cemented femoral components left in place at the time of revision of the acetabular component[J]. J Bone Joint Surg Am. 1997;79(5):701\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBlaha JD. Well-fixed acetabular component retention or replacement: the whys and the wherefores[J]. J Arthroplasty. 2002;17(4 Suppl 1):157\u0026ndash;61.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMasri BA, Mitchell PA, Duncan CP. Removal of solidly fixed implants during revision hip and knee arthroplasty[J]. J Am Acad Orthop Surg. 2005;13(1):18\u0026ndash;27.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePaprosky WG, Weeden SH, Bowling JW Jr. Component removal in revision total hip arthroplasty. Clin Orthop Relat Res. 2001;(393):181\u0026ndash;93.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eD'Antonio JA, Capello WN, Borden LS et al. Classification and management of acetabular abnormalities in total hip arthroplasty[J]. Clin Orthop Relat Res, 1989(243):126\u0026ndash;37.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAdelani MA, Mall NA, Nyazee H, Clohisy JC, Barrack RL, Nunley RM. Revision Total Hip Arthroplasty with Retained Acetabular Component. J Bone Joint Surg Am. 2014;96(12):1015\u0026ndash;20.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLieberman E, Sasala L, Thornton T, et al. Is Retention of the Acetabular Component at Revision Surgery a Long-Term Solution? Arthroplast Today. 2023;23:101197. Published 2023 Aug 26.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRawal JS, Soler JA, Rhee JS, et al. Modification of the explant system for the removal of well fixed hip resurfacing sockets[J]. J Arthroplasty. 2010;25(7):1170\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMitchell PA, Masri BA, Garbuz DS, Greidanus NV, Wilson D, Duncan CP. Removal of well-fixed, cementless, acetabular components in revision hip arthroplasty. J Bone Joint Surg Br. 2003;85(7):949\u0026ndash;52.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAdelani MA, Goodman SB, Maloney WJ, et al. Removal of Well-Fixed Cementless Acetabular Components in Revision Total Hip Arthroplasty[J]. Orthopedics. 2016;39(2):e280\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eNjoku I, Surace P, Piuzzi NS, et al. Acetabular Component Removal Systems. JBJS Rev. 2023;11(4):e2200246.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDeirmengian GK, Zmistowski B, O'Neil JT, et al. Manage ment of acetabular bone loss in revision total hip arthroplas ty[J]. J Bone Joint Surg Am. 2011;93(19):1842\u0026ndash;52.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRudelli S, Uip D, Honda E, et al. One-stage revision of infected total hip arthroplasty with bone graft. J Arthroplasty. 2008;23(8):1165\u0026ndash;77.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eUdomkiat P, Wan Z, Dorr LD. Comparison of preoperative radiographs and intraoperative findings of fixation of hemispheric porous-coated sockets[J]. J Bone Joint Surg Am. 2001;83(12):1865\u0026ndash;70.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMallory TH, Lombardi AJ, Fada RA et al. Noncemented acetabular component removal in the presence of osteolysis: the affirmative[J]. Clin Orthop Relat Res, 2000(381):120\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLachiewicz PF, Anspach WR. Removal of a well fixed acetabular component. A brief technical note of a new method[J]. J Bone Joint Surg Am. 1991;73(9):1355\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePierson JL, Jasty M, Harris WH. Techniques of extraction of well-fixed cemented and cementless implants in revision total hip arthroplasty[J]. Orthop Rev. 1993;22(8):904\u0026ndash;16.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBhutta MA, Gambhir A. Using the Explant Acetabular Cup Removal System for removing a well-fixed resurfacing cementless acetabular component[J]. Ann R Coll Surg Engl. 2009;91(4):344.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBlumenfeld TJ. Removing a well-fixed nonmodular large-bearing cementless acetabular component: a simple modification of an existing removal device[J]. J Arthroplasty. 2010;25(3):491\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePreiss RA, Patil S, Meek RM. The use of modular femoral head trials to centre the Explant blade facilitates retrieval of well-fixed acetabular components with minimal bone defect. Arch Orthop Trauma Surg. 2011;131(7):1003\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKwong L, Billi F, Keller S, Kavanaugh A, Luu A, Paprosky W. A Comparative Study Between the Stryker EZout Powered Acetabular Revision System and the Zimmer Explant Acetabular Cup Removal Systems. Techniques Orthop. 2021;36(2):129\u0026ndash;36.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDaum WJ, Calhoun JH. Removal of the acetabular component minimizing destruction of the bone bed[J]. J Arthroplasty. 1988;3(4):379\u0026ndash;80.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhang X, Hu F, He R, et al. A simple technique to remove well-fixed acetabular components in revision of total hip arthroplasty[J]. Arthroplast Today. 2017;3(4):251\u0026ndash;2.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTarabichi S, Baker CM, Lizcano JD, Abe EA, et al. Porous Metal Augments Have Comparable Outcomes to Other Constructs for Severe Acetabular Bone Loss at Mid-Term Follow-up[J]. J Arthroplasty. 2024;39(12):3041\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGianakos AL, Saad BN, Haring R, et al. Tranexamic acid lowers transfusion requirements and hospital length of stay following revision total hip or knee arthroplasty. Patient Saf Surg. 2021;15(1):21.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePalmer AJR, Lloyd TD, Gibbs VN, et al. The role of intra-operative cell salvage in patient blood management for revision hip arthroplasty: a prospective cohort study. Anaesthesia. 2020;75(4):479\u0026ndash;86.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"total hip arthroplasty, revision, implant removal, vertical shear force, bone defect","lastPublishedDoi":"10.21203/rs.3.rs-7773136/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7773136/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003eRemoving a well-fixed acetabular cup is technically challenging with the risk of complications during revision hip arthroplasty. A new strategy was developed to detach the cup from the acetabulum by impacting on the ring with a designed instrument. This study aimed to investigate the safety and efficiency of the new strategy in removing the well-fixed acetabular components by comparing them with those removed using the Explant Acetabular Cup Removal System.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eThis retrospective study included 70 patients who underwent revision total hip arthroplasty in our center between 2019 and 2022. Patients with acetabular removed by the new technique (n\u0026thinsp;=\u0026thinsp;32) or the Explant System (ES) were recruited (n\u0026thinsp;=\u0026thinsp;38), followed up for a minimum of 2 years. The new strategy aimed to break the connection between bone and cup by impacting on the ring of cup with a designed instrument to create a vertical shear force (VSF) along the hemispherical shape of the acetabular surface. The diameter of the removed and re-implanted cup, severity of acetabular bone defect, hip joint function score, and complications were retrieved and compared between the two groups. The Wilcoxon-Mann\u0026ndash;Whitney test (two-tailed) was used to assess intergroup differences in the acetabular cup size, bone defect severity, preoperative and final follow-up Harris Hip Scores (HHS). Intergroup differences in bone grafting and metal augment utilization were analyzed using chi-square tests.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eThe average and median diameter of the revised cup was 1.7 mm and 2 mm larger than that of the removed cup in the VSF group, while 3.2 mm and 3.0 mm in the ES group. Metal augments were more frequently used in the ES group than in the VSF group. The patients were followed up for an average of 34 months in the VSF group and 50 months in the ES group, and none of them required re-revision due to acetabular component loosening. The mean HHS improved in both groups.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eThe VSF strategy is safe, efficient, and cost-effective in removing the well-fixed acetabular cup while preserving bone stock during revision hip arthroplasty.\u003c/p\u003e","manuscriptTitle":"The safety and efficiency of a new strategy to remove the well-fixed cementless acetabular components in revision hip arthroplasty: a retrospective comparative study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-20 00:46:14","doi":"10.21203/rs.3.rs-7773136/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-12-10T09:22:27+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-04T10:49:45+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-02T01:46:40+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-19T09:56:06+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-18T14:08:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"277999401400386937951430190398091378720","date":"2025-11-18T13:45:03+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"7114418993074685804153661044835358830","date":"2025-11-17T21:53:18+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"148461175433849860841531271360383349249","date":"2025-11-12T11:01:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"175235348469370701477023675843131073850","date":"2025-11-12T10:29:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"213609243150986086364423640643355522530","date":"2025-11-11T18:34:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"267113343776497773720312048583574473395","date":"2025-11-11T06:23:44+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-11-09T14:23:37+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-11-07T11:44:19+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-15T07:51:21+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-14T01:42:21+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Musculoskeletal Disorders","date":"2025-10-14T01:38:57+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e0c29a84-1fa3-48f4-861f-cdc76417714e","owner":[],"postedDate":"November 20th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-02-09T16:05:34+00:00","versionOfRecord":{"articleIdentity":"rs-7773136","link":"https://doi.org/10.1186/s12891-026-09581-8","journal":{"identity":"bmc-musculoskeletal-disorders","isVorOnly":false,"title":"BMC Musculoskeletal Disorders"},"publishedOn":"2026-02-07 15:59:07","publishedOnDateReadable":"February 7th, 2026"},"versionCreatedAt":"2025-11-20 00:46:14","video":"","vorDoi":"10.1186/s12891-026-09581-8","vorDoiUrl":"https://doi.org/10.1186/s12891-026-09581-8","workflowStages":[]},"version":"v1","identity":"rs-7773136","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7773136","identity":"rs-7773136","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}