Physical therapy for patients with anterior disc displacement without reduction at different levels of pain: an observational study

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However, the severity of symptoms in patients with ADDWOR varies, especially with different pain levels. Few studies investigate how these variables affect patient efficacy or treatment requirements. Therefore, we evaluated the effectiveness and characteristics of comprehensive physical therapy in patients with ADDWOR at different levels of pain severity. Methods This observational study recruited 91 patients with ADDWOR, and they were divided into two groups based on pain severity: mild pain (n = 46) and significant pain (n = 45). Comprehensive physical therapy was administered, and the following outcome measures were evaluated before and after treatment: visual analogue scale (VAS) score of pain, maximum mouth opening assessment, jaw functional limitation scale questionnaire, Patient Health Questionnaire 15, Patient Health Questionnaire 9, and generalised anxiety disorder 7. Treatment frequency and duration were also recorded. Independent sample t-tests or Mann–Whitney U tests were used for intergroup differences, and paired sample t-tests or Mann–Whitney U tests were used for intragroup differences. Results After treatment, no significant differences were found in any of the evaluation indices (P > 0.05) between the two groups, except for the VAS and treatment frequency (P < 0.05). Both groups showed significant improvement in all indicators before and after treatment, except for VAS in the mild pain group, which showed no significant change. Comprehensive physical therapy alleviated physical symptoms and positively impacted mental health in patients with ADDWOR and significant pain requiring more frequent treatments. Conclusions Comprehensive physical therapy alleviated physical symptoms, such as active mouth opening and pain, and positively affected the mental health of patients with ADDWOR. However, patients with significant pain levels may require more frequent treatments to achieve optimal results. Temporomandibular joint disorder Anterior disc displacement without reduction Physical therapy Pain management Background Temporomandibular joint disorders (TMD) are a group of diseases involving the temporomandibular joint and masticatory muscles with symptoms of limited mouth opening, clicking, or pain [ 1 ] . Anterior disc displacement without reduction (ADDWOR) is a common subtype seen in clinical settings [ 2 , 3 ] . Patients with ADDWOR frequently encounter limited mouth opening and orofacial pain, which significantly affects their quality of life and necessitates professional intervention [ 4 , 5 ] . Physical therapy, including modality therapy such as laser therapy, ultrasound therapy, and low-frequency electrotherapy, as well as manual therapy such as soft tissue relaxation and joint mobilisation techniques, is widely used to treat ADDWOR [ 6 – 8 ] . These therapies effectively relax and treat the local masticatory muscles and temporomandibular joint, improving symptoms such as limited mouth opening and pain in patients with ADDWOR [ 9 ] . Fang et al. [ 10 ] conducted comprehensive physical therapy on 256 patients with ADDWOR, resulting in prompt and long-term significant improvements in the maximum degree of active mouth opening, pain, and function. However, the degree of symptoms in patients with ADDWOR varies, particularly with individual differences in pain levels. Few reports address the impact of these differences on patient efficacy or treatment requirements. Therefore, this study aimed to investigate the therapeutic effect of physical therapy on patients with ADDWOR with varying pain severity levels and to investigate the treatment frequency and course requirements for these patients. Methods This was an observational study. Patients were divided into mild pain group (MPG) or significant pain group (SPG) according to different visual analogue scale (VAS) scores. Patients with VAS < 3 were categorised into the MPG, and patients with VAS ≥ 3 points were categorised into the SPG. Based on pre-experimental results, the mean treatment frequency of the MPG and SPG was 5.20 and 7.27, respectively, with α set at 0.05 bilaterally and a confidence level of 90%. The sample size for each group was calculated to be 40 cases using the PASS 15 software (NCSS, USA). The calculation was based on 20% owing to the possibility of lost or refused visits. Consequently, a minimum of 50 participants was required for each group. After participant attrition and exclusion, 50 patients were included in the MPG group and 51 patients in the SPG control group. This study was approved by the Ethics Committee of the Ninth People’s Hospital affiliated to Shanghai Jiao Tong University School of Medicine (Approval Number: SH9H-2019-T316-4). All patients with ADDWOR underwent comprehensive physical therapy based on the severity of their symptoms until significant improvement in pain and mandibular function was observed. Moreover, all patients underwent pain assessments, mouth-opening measurements, and self-assessment questionnaires before and after treatment. Participants Between November 2021 and December 2022, 91 patients with TMD were recruited from the Department of Rehabilitation Medicine, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine. Patients aged 18–45 years who met the diagnostic criteria for ADDWOR were included, while those with rheumatoid arthritis, dislocation or fracture of the temporomandibular joint, symptoms of neurological damage, significant visceral organ lesions, pregnancy, cognitive impairment, those who received analgesics in the temporomandibular joint during the intervention period, and those who could not participate in the study were excluded. No differences were observed in general characteristics of patients such as age, sex or education between the MPG and SPG. All the patients were aware of the study’s purpose and signed an informed consent form before participation, with the option to withdraw at any time. Maximum mouth-opening (MMO) assessment All patients were comfortably seated with their feet flat on the floor while the evaluator sat on the opposite side and instructed them to open their mouths as wide as possible. The distance between the upper and lower central incisors was measured and recorded using a graduated scale. This measurement represented the patient’s active maximum degree of mouth opening [ 11 ] . Visual analogue scale (VAS) The patients were presented with a scale ranging from 0–10, indicating no pain on the left (0) to severe pain on the right (10). They then rated their pain intensity in the temporomandibular joint during the maximum degree of active mouth opening. The evaluation was repeated three times, and the average intensity was recorded [ 12 ] . Questionnaires All patients completed the following questionnaires: Jaw Functional Limitation Scale (JFLS), patient health questionnaire 15 (PHQ15), patient health questionnaire 9 (PHQ9), and generalised anxiety disorder 7 (GAD7). JFLS: The JFLS consists of 20 items, evaluating chewing function, eating with the mouth open, speaking, and other activities. Each item has a score of 0–10, with higher scores indicating severe restriction. The sum of the scores for each item indicated the overall level of mandibular function in the patient [ 13 ] . PHQ15: assesses whether a patient has had somatisation symptoms in the previous month using 15 items. Each item was scored from 0 to 2 points, with a total of 30 possible points. The higher the total score, the more pronounced the somatisation symptoms. Total scores of 0–4, 5–9, 10–14, and 15–30 indicate normal, mild, moderate, and severe somatisation, respectively [ 14 ] . PHQ9: evaluates patients’ depression level with nine items, scored from 0–3, totalling 27 points. The higher the total score, the higher the patient’s depression level. The emotional level of the patients in the previous two weeks was evaluated with a total score of 0–4, 5–9, 10–14, 15–19, and 20–27, indicating no, mild, moderate, moderate-to-severe, and severe depression, respectively [ 15 ] . GAD7: assesses the anxiety level of patients with a total of seven items, each with a score of 0–3 points, for a total of 21 points. The higher the score, the higher the patient’s anxiety level. The psychological state of the patients in the previous 2 weeks was evaluated, with total scores of 0–4, 5–9, 10–14, and 15–21 indicating no, mild, moderate, and severe anxiety, respectively [ 16 ] . Comprehensive physical therapy Modality therapy: All patients received modality therapy, including ultrasound, low-intensity laser, and low-frequency electrotherapy. During ultrasound therapy (US-750, ITO, US-750 in Japan), patients were comfortably seated as their temporomandibular joint or masticatory muscle was coupled with a coupling agent using the mobile method. The treatment frequency was 1 MHz; the control ratio, 100%; intensity, 0.8–1.2 W/cm 2 ; and duration, 3 min per session [ 8 ] . During low-intensity laser therapy (LA-400, Han Tang, China), patients were seated comfortably, and an adsorption-type laser was applied to the temporomandibular joint or masticatory muscle pain area. The treatment intensity was 60 mW, and the continuous output time was 10 min [ 17 ] . During low-frequency electrotherapy (MK120G, MINITO, MK120G Japan), patients were also seated comfortably, and an adsorption-type low-frequency output channel was placed around the temporomandibular joint and masseter muscle. The treatment frequency was 50 Hz, and the intensity was adjusted to the maximum tolerable level, with a duration of 10 min per session [ 18 ] . Manual therapy: All patients received manual treatment, including masticatory muscle relaxation and temporomandibular joint mobilisation, from the same rehabilitation therapist [ 19 ] . While relaxing their masticatory muscles, the patients were seated comfortably. The therapist gently and vertically relaxed their temporal and masseter muscles toward the muscle fibres and pressed the trigger points to relax the inner and outer pterygoid muscles. Each treatment lasted for 3–5 minutes. During joint mobilisation techniques, the therapist wore sterile gloves, extended the thumb of the operating hand into the patient’s mouth, and placed it in the posterior molar area. The remaining four fingers grasped the mandibular branch, slightly fixed to the patient’s head. The middle finger was used to observe the condylar movement during the operation. The operator performed long-axis traction and forward sliding on the temporomandibular joint, with each treatment lasting 3–5 min [ 20 , 21 ] . All patients with ADDWOR underwent comprehensive physical therapy, depending on the severity of their condition. Initially, the patients received three-modality therapy, followed by manual therapy, which was administered by the same senior physical therapist until the pain and mandibular function improved. All patients underwent mouth-opening measurements, pain assessments, and self-assessment questionnaires before and after the first treatment. Each patient was required to complete two evaluations throughout the therapy, conducted by a senior physical therapist who was unaware of the patient’s specific treatment situation. Statistical analysis Data were analysed using SPSS software (version 22.0; IBM, Armonk USA, NY). The Kolmogorov − Smirnov test determined the normality of the measured data. Normally distributed data are presented as mean (standard deviation). Non-parametric or paired t-tests were used to examine intragroup changes in the scores of the various indicators before and after treatment, and an independent t-test or non-parametric test was used for intergroup differences. Statistical significance was set at p < 0.05 bilaterally. Results General information Of the 50 patients initially included in the MPG group, 4 patients discontinued treatment and were excluded. In the SPG group, of the 51 patients initially enrolled, 6 patients were excluded due to discontinued treatment or incomplete information. Overall, 91 patients with ADDWOR, comprising 46 with MPG and 45 with SPG, were included in this study. The patients’ general characteristics, such as mean age and body mass index, are shown in Table 1 , while other parameters before treatment, such as MMO, VAS score, and jaw function, are presented in Table 2 . Table 1 General characteristics of patients MPG SPG Z/x 2 p Sex (M/F) 3/43 1/44 4.000 0.261 Age(years) 29.50(14.25) 29.00(9.50) -1.394 0.163 BMI (kg/m 2 ) 19.17(2.32) 20.03(3.02) -1.139 0.255 Ethnic group 2.000 0.157 Han nationality 44 45 Minority nationality 2 0 Marital status 2.286 0.319 Unmarried 25 29 Married 19 15 Divorced 0 1 Residence 0.000 0.987 Urban 45 44 Rural 1 1 Education level 5.073 0.079 High school 10 10 College degree 31 22 Postgraduate degree 5 13 MPG, mild pain group; SPG: Significant pain group. Table 2 Intra and inter-group differences before and after treatment MPG SPG Z/t p VAS T0 1.00(0.94) 4.51(1.34) -8.335 <0.001 * T1 1.07(1.37) 2.16(1.78) -3.357 0.001 * Z -0.158 -4.804 P 0.875 <0.001 * MMO T0 26.91(5.10) 27.27(5.27) -0.537 0.591 T1 36.72(3.60) 38.00(4.18) -1.264 0.206 Z -5.606 -5.705 P <0.001 * <0.001 * PHQ15 T0 4.50(3.76) 5.44(4.33) -0.893 0.372 T1 2.63(2.73) 4.04(3.62) -1.824 0.068 Z -4.361 -3.447 P <0.001 * 0.001 * PHQ9 T0 4.61(3.95) 5.18(4.64) -0.228 0.820 T1 2.70(3.13) 3.42(3.47) -1.272 0.204 Z -4.415 -3.394 P <0.001 * 0.001 * GAD7 T0 3.96(3.53) 4.42(4.70) -0.052 0.958 T1 2.22(2.97) 2.56(2.81) -0.829 0.407 Z -4.449 -3.317 P <0.001 * 0.001 * JFLS T0 43.61(21.91) 54.67(19.55) -2.539 0.013 * T1 23.85(18.38) 23.13(16.32) 0.196 0.845 t 6.146 10.483 P <0.001 * <0.001 * Treatment Frequency 5.61(2.23) 7.38(4.05) -2.120 0.034 * Treatment Course 14.85(10.62) 18.91(15.41) -1.039 0.299 MPG: Mild pain group; SPG: Significant pain group; VAS: Visual analog scale score of pain; MMO: Maximum mouth opening; JFLS: Jaw functional limitation scale; PHQ15: Patient health questionnaire-15, PHQ9: Patient health questionnaire-9, GAD7: Generalised Anxiety Scale; T0: Before treatment; T1: After treatment; * p < 0.05. Intragroup changes before and after treatment Except for no difference in the VAS scores before and after treatment in the MPG (p = 0.875), significant differences were observed in the mandibular function and mental health level scores between the two groups (p < 0.05). Specifically, the VAS scores significantly decreased in the SPG following treatment (p < 0.05). The results are summarised in Table 2 . Intergroup changes before and after treatment The VAS scores differed between the two groups before and after treatment, with the SPG group exhibiting higher VAS scores than the MPG group (p < 0.05). Additionally, a difference in the JFLS scores was observed between the two groups before treatment (p < 0.05), with the SPG group scoring higher than the MPG group, but no difference was observed after treatment (p = 0.845). No significant differences were found in the remaining parameters before and after treatment (p > 0.05). Furthermore, the total number of treatments differed between the two groups, with the SPG group having a higher treatment frequency than the MPG group (p = 0.034). However, no significant difference was noted in the total treatment course between the two groups (p = 0.299). The results are summarised in Table 2 . Discussion Our findings revealed that comprehensive physical therapy significantly improved both high and low levels of pain, active mouth opening, and mandibular function, as well as mental health, in patients with ADDWOR. However, individuals experiencing high levels of pain necessitated more frequent treatments within the same treatment course, highlighting varied treatment needs based on pain severity. Physical therapy is a commonly used method for TMD treatment, and numerous studies have indicated its efficacy in improving mouth opening and short-term pain, thereby improving temporomandibular joint function and long-term efficacy [ 6 , 10 ] . Nagata et al. [ 20 ] conducted an 18-week follow-up evaluation of patients with TMD who received manual treatment and found a significant improvement in patients with limited mouth opening and maxillofacial pain following treatment and subsequent follow-up. Physical therapy promotes blood circulation, muscle relaxation, and analgesia in the temporomandibular joint or chewing muscles through methods like photothermal, acoustic, and electrical stimulation, while manual therapy requires manual manipulation by rehabilitation therapists and commonly used techniques, including local and related muscle relaxation and joint loosening techniques [ 22 ] . Patients with TMD often exhibit adverse oral behaviours such as unilateral chewing, critical teeth, preference for hard objects, and excessive joint movement, resulting in tension in the masseter, medial pterygoid, temporal pterygoid, and lateral pterygoid muscles, as well as significant soreness and pain during compression. When comparing patients with TMD to healthy individuals, Paulino et al. found that the presence of signs and symptoms of TMD was associated with parafunctional habits [ 23 ] . Muscle massage can effectively relieve and relax tired or spasmodic muscles [ 21 , 24 ] . Joint mobilisation technology aids in the quick adaptation of the articular capsule and surrounding ligaments to widen mouth opening. This is achieved by vibrating, separating, or sliding the temporomandibular joint, causing minimal to no pain to the patient while addressing limited mouth opening or joint area symptoms. Physical therapy, being non-invasive, offers high cost-effectiveness and short treatment cycles. In this study, patients received an average of five to seven treatments over a 2 − 3-week period, making it highly suitable for those with ADDWOR [ 25 ] . Following physical therapy in patients with varying levels of pain, those with significant pain were able to recover their jaw function and mental health to the same level as those with milder pain. However, these patients require a higher treatment frequency in the same treatment cycle, indicating a need for higher treatment density. This emphasises the importance of doctors anticipating different treatment costs based on pain severity. Despite a small average treatment frequency difference of two sessions between the two groups in this study, this remains more easily accepted by patients in clinical practice. In this study, there were no significant differences in the pain scores in the MPG group before and after treatment, likely due to their lower pain scores before treatment, averaging only 1 point. Nevertheless, there was a significant improvement in maximum active mouth opening and jaw function scores, indicating a positive effect of the physical therapy. This could be attributed to the symptomatology of patients with ADDWOR. Some of these patients may have significant limitations in mouth opening, jaw function, and daily life functions but low pain levels. Consequently, manual therapy and exercise training instilled confidence and cooperation and reduced fear in patients, leading to faster recovery and lower treatment frequency. Although there was a statistically significant difference in the average pain scores between the SPG and MPG groups after treatment, the difference of less than two points lacked clinical significance [ 26 ] . Notably, the pain score of the SPG group improved significantly after treatment, surpassing that of the MPG group. This trend was consistent in jaw function scores, further demonstrating the positive effects of physical therapy on pain improvement. When the baseline data were analysed, no significant differences were found in the mental health levels between the two groups of patients, which was unexpected. It was initially hypothesised that patients with significant pain exhibit lower levels of mental health given the common association of negative emotions—such as anxiety, depression, somatisation, and catastrophising are often associated—with more severe pain [ 27 , 28 ] . However, the lack of difference between the two groups does not indicate that both groups of patients are psychologically healthy. Both groups had average PHQ15, PHQ9, and GAD7 scores in the mild-to-moderate range. Previous studies have shown that individuals with TMD generally have lower levels of mental health compared to healthy individuals [ 29 , 30 ] . Therefore, while no difference was found between the two groups in this study, a correlation between psychological effects and TMD symptoms cannot be completely ruled out. To promote symptom recovery, this factor should be considered during treatment. During manual therapy, patients and therapists can communicate fully and exchange detailed information about their diseases, which may help alleviate negative emotions. This study has some limitations. Firstly, it primarily focused on patients with ADDWOR who often experienced pain and significant limitations in mouth opening, prompting them to seek hospital treatment. Other subtypes of TMD were not included, such as myofascial pain or clicking with pain. Future research should explore the relationship between pain levels and the treatment needs of other types of patients. Additionally, this study focused only on the treatment and recovery of patients aged 18 − 45. While TMD is more common in this age group [ 31 ] , the pain in older age groups may be related to other factors, such as degeneration, leading to higher treatment demands, including drug use and injections. Further exploration should be conducted in this group of people in the future. Conclusions Comprehensive physical therapy, a commonly used treatment modality for TMD, can not only alleviate patient pain, improve active mouth opening, and facilitate jaw function but also effectively support their mental health. This study demonstrates that patients with significant pain require more frequent physical therapy. Abbreviations ADDWOR- Anterior disc displacement without reduction GAD7- Generalised anxiety disorder 7 JFLS- Jaw Functional Limitation Scale MMO- Maximum mouth-opening MPG- Mild pain group PHQ15- Patient health questionnaire 15 PHQ9- Patient health questionnaire 9 SPG- Significant pain group TMD- Temporomandibular joint disorders VAS- Visual analogue scale Declarations Ethics approval and consent to participate: This study was approved by the Ethics Committee of the Ninth People’s Hospital affiliated to Shanghai Jiao Tong University School of Medicine (Approval Number: SH9H-2019-T316). All the patients were aware of the study’s purpose and signed an informed consent form before participation, with the option to withdraw at any time. Clinical Trial Registration: Chinese Clinical Trial Registry (ChiCTR1800018369). Consent for publication: Not applicable. Availability of data and materials: Data can be available on reasonable request from the corresponding author. Competing interests: The authors declare that they have no competing interests. Funding: We appreciate the support of relevant funds for this study, which was supported by the Fundamental Research Funds for the Central Universities (YG2024QNA25); Fundamental research program funding of Ninth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine (JYZZ229); The Program of Key Supporting Disciplines of Shanghai Health System (2023ZDFC0303); and Special Project for Clinical Research of Health Industry of Shanghai Health Commission (202340129). Authors’ contributions: Yuan Yao contributed to conception, design, data acquisition and interpretation, performed all statistical analyses, and drafted and critically revised the manuscript. Yang Yang and Sha Sha Liu contributed to conception, design, data acquisition, and interpretation. Hong Zeng and Shen Ji Lu contributed to design, performed all statistical analyses, and drafted and critically revised the manuscript. 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Association of clinical findings of temporomandibular disorders (TMD) with self‐reported musculoskeletal pains. Eur J Pain . 2012;15:1061-1067. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6903111","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":492743438,"identity":"ad24d5ee-4d58-4e15-8794-f0a22df7b08e","order_by":0,"name":"Yuan Yao","email":"","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Yuan","middleName":"","lastName":"Yao","suffix":""},{"id":492743440,"identity":"e98841df-57ac-4f7b-b1be-1135375b9296","order_by":1,"name":"Zhong Yi Fang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAz0lEQVRIiWNgGAWjYJACxg8/QBTzgQMQBgHAA1Ir2WMApNgSD87sIVILAw8bSAuP8WEONiK02LP3HpOQ4PkjZy6R8+Ew0AR5frEDBGzhOZcmUWBhYGw5I3fD4QILBsOZsxMIaJHIMQPaYpC44QZQywwehgSD28RoAfoFqCXnwWEeNhK1MBCp5cwZY2vJHmNjgzPPDICBLEHYL+ztPYY3P/yQkzM4nvz4w4cfNvL80gS0AAGLBJgSAKuUIKgcBJg/gCn+A0SpHgWjYBSMghEIAMO9Qez90d+9AAAAAElFTkSuQmCC","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":true,"prefix":"","firstName":"Zhong","middleName":"Yi","lastName":"Fang","suffix":""},{"id":492743443,"identity":"890fba2e-4fbe-4dc1-960e-12c4221cb58a","order_by":2,"name":"Yang Yang","email":"","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Yang","middleName":"","lastName":"Yang","suffix":""},{"id":492743445,"identity":"692754ae-d47f-450b-913e-add48dc90d83","order_by":3,"name":"Sha Sha Liu","email":"","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Sha","middleName":"Sha","lastName":"Liu","suffix":""},{"id":492743447,"identity":"7a42d28a-715b-47b6-80d2-3ca540b1d21f","order_by":4,"name":"Lei Jin","email":"","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Lei","middleName":"","lastName":"Jin","suffix":""},{"id":492743449,"identity":"fb0d5534-7559-4b10-8312-a9d061dac09a","order_by":5,"name":"Shen Ji Lu","email":"","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Shen","middleName":"Ji","lastName":"Lu","suffix":""},{"id":492743450,"identity":"ae0044a6-4627-4de5-a6d5-0c92e1828250","order_by":6,"name":"Hong Zeng","email":"","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Hong","middleName":"","lastName":"Zeng","suffix":""},{"id":492743451,"identity":"d078475f-7469-4b6f-aba2-7a7e68786408","order_by":7,"name":"Xin Jiang","email":"","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Xin","middleName":"","lastName":"Jiang","suffix":""},{"id":492743453,"identity":"685f0af1-7341-4e80-ad34-7a2c031e4028","order_by":8,"name":"Bin Cai","email":"","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Bin","middleName":"","lastName":"Cai","suffix":""},{"id":492743455,"identity":"07d4f1b7-b020-44c7-8c21-aee9b125277c","order_by":9,"name":"Li Li Xu","email":"","orcid":"","institution":"Shanghai Jiao Tong University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Li","middleName":"Li","lastName":"Xu","suffix":""}],"badges":[],"createdAt":"2025-06-16 08:08:44","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6903111/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6903111/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88785466,"identity":"ba05d238-9f89-4cc5-b0b7-34557466781b","added_by":"auto","created_at":"2025-08-11 11:39:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":757448,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6903111/v1/ca71920d-cc48-4472-a4f0-e15ab1b7cdd3.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Physical therapy for patients with anterior disc displacement without reduction at different levels of pain: an observational study","fulltext":[{"header":"Background","content":"\u003cp\u003eTemporomandibular joint disorders (TMD) are a group of diseases involving the temporomandibular joint and masticatory muscles with symptoms of limited mouth opening, clicking, or pain\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. Anterior disc displacement without reduction (ADDWOR) is a common subtype seen in clinical settings\u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e. Patients with ADDWOR frequently encounter limited mouth opening and orofacial pain, which significantly affects their quality of life and necessitates professional intervention\u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003ePhysical therapy, including modality therapy such as laser therapy, ultrasound therapy, and low-frequency electrotherapy, as well as manual therapy such as soft tissue relaxation and joint mobilisation techniques, is widely used to treat ADDWOR\u003csup\u003e[\u003cspan additionalcitationids=\"CR7\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e. These therapies effectively relax and treat the local masticatory muscles and temporomandibular joint, improving symptoms such as limited mouth opening and pain in patients with ADDWOR\u003csup\u003e[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]\u003c/sup\u003e. Fang et al.\u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e conducted comprehensive physical therapy on 256 patients with ADDWOR, resulting in prompt and long-term significant improvements in the maximum degree of active mouth opening, pain, and function.\u003c/p\u003e\u003cp\u003eHowever, the degree of symptoms in patients with ADDWOR varies, particularly with individual differences in pain levels. Few reports address the impact of these differences on patient efficacy or treatment requirements. Therefore, this study aimed to investigate the therapeutic effect of physical therapy on patients with ADDWOR with varying pain severity levels and to investigate the treatment frequency and course requirements for these patients.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis was an observational study. Patients were divided into mild pain group (MPG) or significant pain group (SPG) according to different visual analogue scale (VAS) scores. Patients with VAS\u0026thinsp;\u0026lt;\u0026thinsp;3 were categorised into the MPG, and patients with VAS\u0026thinsp;\u0026ge;\u0026thinsp;3 points were categorised into the SPG. Based on pre-experimental results, the mean treatment frequency of the MPG and SPG was 5.20 and 7.27, respectively, with α set at 0.05 bilaterally and a confidence level of 90%. The sample size for each group was calculated to be 40 cases using the PASS 15 software (NCSS, USA). The calculation was based on 20% owing to the possibility of lost or refused visits. Consequently, a minimum of 50 participants was required for each group. After participant attrition and exclusion, 50 patients were included in the MPG group and 51 patients in the SPG control group.\u003c/p\u003e\u003cp\u003e This study was approved by the Ethics Committee of the Ninth People\u0026rsquo;s Hospital affiliated to Shanghai Jiao Tong University School of Medicine (Approval Number: SH9H-2019-T316-4). All patients with ADDWOR underwent comprehensive physical therapy based on the severity of their symptoms until significant improvement in pain and mandibular function was observed. Moreover, all patients underwent pain assessments, mouth-opening measurements, and self-assessment questionnaires before and after treatment.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eParticipants\u003c/h2\u003e\u003cp\u003eBetween November 2021 and December 2022, 91 patients with TMD were recruited from the Department of Rehabilitation Medicine, Shanghai Ninth People\u0026rsquo;s Hospital, Shanghai Jiao Tong University School of Medicine. Patients aged 18\u0026ndash;45 years who met the diagnostic criteria for ADDWOR were included, while those with rheumatoid arthritis, dislocation or fracture of the temporomandibular joint, symptoms of neurological damage, significant visceral organ lesions, pregnancy, cognitive impairment, those who received analgesics in the temporomandibular joint during the intervention period, and those who could not participate in the study were excluded. No differences were observed in general characteristics of patients such as age, sex or education between the MPG and SPG. All the patients were aware of the study\u0026rsquo;s purpose and signed an informed consent form before participation, with the option to withdraw at any time.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eMaximum mouth-opening (MMO) assessment\u003c/h3\u003e\n\u003cp\u003eAll patients were comfortably seated with their feet flat on the floor while the evaluator sat on the opposite side and instructed them to open their mouths as wide as possible. The distance between the upper and lower central incisors was measured and recorded using a graduated scale. This measurement represented the patient\u0026rsquo;s active maximum degree of mouth opening\u003csup\u003e[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\n\u003ch3\u003eVisual analogue scale (VAS)\u003c/h3\u003e\n\u003cp\u003eThe patients were presented with a scale ranging from 0\u0026ndash;10, indicating no pain on the left (0) to severe pain on the right (10). They then rated their pain intensity in the temporomandibular joint during the maximum degree of active mouth opening. The evaluation was repeated three times, and the average intensity was recorded\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\n\u003ch3\u003eQuestionnaires\u003c/h3\u003e\n\u003cp\u003eAll patients completed the following questionnaires: Jaw Functional Limitation Scale (JFLS), patient health questionnaire 15 (PHQ15), patient health questionnaire 9 (PHQ9), and generalised anxiety disorder 7 (GAD7).\u003c/p\u003e\u003cp\u003eJFLS: The JFLS consists of 20 items, evaluating chewing function, eating with the mouth open, speaking, and other activities. Each item has a score of 0\u0026ndash;10, with higher scores indicating severe restriction. The sum of the scores for each item indicated the overall level of mandibular function in the patient\u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003ePHQ15: assesses whether a patient has had somatisation symptoms in the previous month using 15 items. Each item was scored from 0 to 2 points, with a total of 30 possible points. The higher the total score, the more pronounced the somatisation symptoms. Total scores of 0\u0026ndash;4, 5\u0026ndash;9, 10\u0026ndash;14, and 15\u0026ndash;30 indicate normal, mild, moderate, and severe somatisation, respectively\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003ePHQ9: evaluates patients\u0026rsquo; depression level with nine items, scored from 0\u0026ndash;3, totalling 27 points. The higher the total score, the higher the patient\u0026rsquo;s depression level. The emotional level of the patients in the previous two weeks was evaluated with a total score of 0\u0026ndash;4, 5\u0026ndash;9, 10\u0026ndash;14, 15\u0026ndash;19, and 20\u0026ndash;27, indicating no, mild, moderate, moderate-to-severe, and severe depression, respectively\u003csup\u003e[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eGAD7: assesses the anxiety level of patients with a total of seven items, each with a score of 0\u0026ndash;3 points, for a total of 21 points. The higher the score, the higher the patient\u0026rsquo;s anxiety level. The psychological state of the patients in the previous 2 weeks was evaluated, with total scores of 0\u0026ndash;4, 5\u0026ndash;9, 10\u0026ndash;14, and 15\u0026ndash;21 indicating no, mild, moderate, and severe anxiety, respectively\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\n\u003ch3\u003eComprehensive physical therapy\u003c/h3\u003e\n\u003cp\u003eModality therapy: All patients received modality therapy, including ultrasound, low-intensity laser, and low-frequency electrotherapy. During ultrasound therapy (US-750, ITO, US-750 in Japan), patients were comfortably seated as their temporomandibular joint or masticatory muscle was coupled with a coupling agent using the mobile method. The treatment frequency was 1 MHz; the control ratio, 100%; intensity, 0.8\u0026ndash;1.2 W/cm\u003csup\u003e2\u003c/sup\u003e; and duration, 3 min per session\u003csup\u003e[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e. During low-intensity laser therapy (LA-400, Han Tang, China), patients were seated comfortably, and an adsorption-type laser was applied to the temporomandibular joint or masticatory muscle pain area. The treatment intensity was 60 mW, and the continuous output time was 10 min\u003csup\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/sup\u003e. During low-frequency electrotherapy (MK120G, MINITO, MK120G Japan), patients were also seated comfortably, and an adsorption-type low-frequency output channel was placed around the temporomandibular joint and masseter muscle. The treatment frequency was 50 Hz, and the intensity was adjusted to the maximum tolerable level, with a duration of 10 min per session\u003csup\u003e[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eManual therapy: All patients received manual treatment, including masticatory muscle relaxation and temporomandibular joint mobilisation, from the same rehabilitation therapist\u003csup\u003e[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/sup\u003e. While relaxing their masticatory muscles, the patients were seated comfortably. The therapist gently and vertically relaxed their temporal and masseter muscles toward the muscle fibres and pressed the trigger points to relax the inner and outer pterygoid muscles. Each treatment lasted for 3\u0026ndash;5 minutes. During joint mobilisation techniques, the therapist wore sterile gloves, extended the thumb of the operating hand into the patient\u0026rsquo;s mouth, and placed it in the posterior molar area. The remaining four fingers grasped the mandibular branch, slightly fixed to the patient\u0026rsquo;s head. The middle finger was used to observe the condylar movement during the operation. The operator performed long-axis traction and forward sliding on the temporomandibular joint, with each treatment lasting 3\u0026ndash;5 min\u003csup\u003e[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eAll patients with ADDWOR underwent comprehensive physical therapy, depending on the severity of their condition. Initially, the patients received three-modality therapy, followed by manual therapy, which was administered by the same senior physical therapist until the pain and mandibular function improved. All patients underwent mouth-opening measurements, pain assessments, and self-assessment questionnaires before and after the first treatment. Each patient was required to complete two evaluations throughout the therapy, conducted by a senior physical therapist who was unaware of the patient\u0026rsquo;s specific treatment situation.\u003c/p\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eData were analysed using SPSS software (version 22.0; IBM, Armonk USA, NY). The Kolmogorov\u0026thinsp;\u0026minus;\u0026thinsp;Smirnov test determined the normality of the measured data. Normally distributed data are presented as mean (standard deviation). Non-parametric or paired t-tests were used to examine intragroup changes in the scores of the various indicators before and after treatment, and an independent t-test or non-parametric test was used for intergroup differences. Statistical significance was set at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 bilaterally.\u003c/p\u003e\u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\u003ch2\u003eGeneral information\u003c/h2\u003e\u003cp\u003eOf the 50 patients initially included in the MPG group, 4 patients discontinued treatment and were excluded. In the SPG group, of the 51 patients initially enrolled, 6 patients were excluded due to discontinued treatment or incomplete information. Overall, 91 patients with ADDWOR, comprising 46 with MPG and 45 with SPG, were included in this study. The patients\u0026rsquo; general characteristics, such as mean age and body mass index, are shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, while other parameters before treatment, such as MMO, VAS score, and jaw function, are presented in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\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\u003eGeneral characteristics of patients\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMPG\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSPG\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eZ/x\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eSex (M/F)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3/43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1/44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e4.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.261\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eAge(years)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e29.50(14.25)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29.00(9.50)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.394\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.163\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e19.17(2.32)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e20.03(3.02)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.139\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.255\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eEthnic group\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.157\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eHan nationality\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eMinority nationality\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eMarital status\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2.286\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.319\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eUnmarried\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eMarried\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eDivorced\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eResidence\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.987\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eUrban\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eRural\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eEducation level\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e5.073\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.079\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eHigh school\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eCollege degree\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003ePostgraduate degree\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003eMPG, mild pain group; SPG: Significant pain group.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eIntra and inter-group differences before and after treatment\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMPG\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSPG\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eZ/t\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVAS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.00(0.94)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.51(1.34)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-8.335\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026lt;0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.07(1.37)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.16(1.78)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-3.357\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eZ\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-0.158\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-4.804\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.875\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMMO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e26.91(5.10)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e27.27(5.27)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-0.537\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.591\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e36.72(3.60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e38.00(4.18)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.264\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.206\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eZ\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-5.606\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-5.705\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026lt;0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePHQ15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4.50(3.76)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5.44(4.33)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-0.893\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.372\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.63(2.73)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.04(3.62)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.824\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.068\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eZ\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-4.361\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-3.447\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026lt;0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePHQ9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4.61(3.95)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5.18(4.64)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-0.228\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.820\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.70(3.13)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3.42(3.47)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.272\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.204\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eZ\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-4.415\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-3.394\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026lt;0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGAD7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.96(3.53)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.42(4.70)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-0.052\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.958\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.22(2.97)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.56(2.81)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-0.829\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.407\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eZ\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-4.449\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-3.317\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026lt;0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eJFLS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e43.61(21.91)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e54.67(19.55)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-2.539\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.013\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e23.85(18.38)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e23.13(16.32)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.196\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.845\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003et\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.146\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e10.483\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026lt;0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;0.001\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTreatment Frequency\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.61(2.23)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7.38(4.05)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-2.120\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.034\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTreatment Course\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e14.85(10.62)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e18.91(15.41)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.039\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.299\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003eMPG: Mild pain group; SPG: Significant pain group; VAS: Visual analog scale score of pain; MMO: Maximum mouth opening; JFLS: Jaw functional limitation scale; PHQ15: Patient health questionnaire-15, PHQ9: Patient health questionnaire-9, GAD7: Generalised Anxiety Scale; T0: Before treatment; T1: After treatment; * p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003eIntragroup changes before and after treatment\u003c/h2\u003e\u003cp\u003eExcept for no difference in the VAS scores before and after treatment in the MPG (p\u0026thinsp;=\u0026thinsp;0.875), significant differences were observed in the mandibular function and mental health level scores between the two groups (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Specifically, the VAS scores significantly decreased in the SPG following treatment (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The results are summarised in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eIntergroup changes before and after treatment\u003c/h2\u003e\u003cp\u003eThe VAS scores differed between the two groups before and after treatment, with the SPG group exhibiting higher VAS scores than the MPG group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Additionally, a difference in the JFLS scores was observed between the two groups before treatment (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), with the SPG group scoring higher than the MPG group, but no difference was observed after treatment (p\u0026thinsp;=\u0026thinsp;0.845). No significant differences were found in the remaining parameters before and after treatment (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e\u003cp\u003eFurthermore, the total number of treatments differed between the two groups, with the SPG group having a higher treatment frequency than the MPG group (p\u0026thinsp;=\u0026thinsp;0.034). However, no significant difference was noted in the total treatment course between the two groups (p\u0026thinsp;=\u0026thinsp;0.299). The results are summarised in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur findings revealed that comprehensive physical therapy significantly improved both high and low levels of pain, active mouth opening, and mandibular function, as well as mental health, in patients with ADDWOR. However, individuals experiencing high levels of pain necessitated more frequent treatments within the same treatment course, highlighting varied treatment needs based on pain severity.\u003c/p\u003e\u003cp\u003ePhysical therapy is a commonly used method for TMD treatment, and numerous studies have indicated its efficacy in improving mouth opening and short-term pain, thereby improving temporomandibular joint function and long-term efficacy\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e. Nagata et al.\u003csup\u003e[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e conducted an 18-week follow-up evaluation of patients with TMD who received manual treatment and found a significant improvement in patients with limited mouth opening and maxillofacial pain following treatment and subsequent follow-up. Physical therapy promotes blood circulation, muscle relaxation, and analgesia in the temporomandibular joint or chewing muscles through methods like photothermal, acoustic, and electrical stimulation, while manual therapy requires manual manipulation by rehabilitation therapists and commonly used techniques, including local and related muscle relaxation and joint loosening techniques\u003csup\u003e[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e. Patients with TMD often exhibit adverse oral behaviours such as unilateral chewing, critical teeth, preference for hard objects, and excessive joint movement, resulting in tension in the masseter, medial pterygoid, temporal pterygoid, and lateral pterygoid muscles, as well as significant soreness and pain during compression. When comparing patients with TMD to healthy individuals, Paulino et al. found that the presence of signs and symptoms of TMD was associated with parafunctional habits\u003csup\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/sup\u003e. Muscle massage can effectively relieve and relax tired or spasmodic muscles\u003csup\u003e[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e. Joint mobilisation technology aids in the quick adaptation of the articular capsule and surrounding ligaments to widen mouth opening. This is achieved by vibrating, separating, or sliding the temporomandibular joint, causing minimal to no pain to the patient while addressing limited mouth opening or joint area symptoms. Physical therapy, being non-invasive, offers high cost-effectiveness and short treatment cycles. In this study, patients received an average of five to seven treatments over a 2\u0026thinsp;\u0026minus;\u0026thinsp;3-week period, making it highly suitable for those with ADDWOR\u003csup\u003e[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eFollowing physical therapy in patients with varying levels of pain, those with significant pain were able to recover their jaw function and mental health to the same level as those with milder pain. However, these patients require a higher treatment frequency in the same treatment cycle, indicating a need for higher treatment density. This emphasises the importance of doctors anticipating different treatment costs based on pain severity. Despite a small average treatment frequency difference of two sessions between the two groups in this study, this remains more easily accepted by patients in clinical practice.\u003c/p\u003e\u003cp\u003eIn this study, there were no significant differences in the pain scores in the MPG group before and after treatment, likely due to their lower pain scores before treatment, averaging only 1 point. Nevertheless, there was a significant improvement in maximum active mouth opening and jaw function scores, indicating a positive effect of the physical therapy. This could be attributed to the symptomatology of patients with ADDWOR. Some of these patients may have significant limitations in mouth opening, jaw function, and daily life functions but low pain levels. Consequently, manual therapy and exercise training instilled confidence and cooperation and reduced fear in patients, leading to faster recovery and lower treatment frequency. Although there was a statistically significant difference in the average pain scores between the SPG and MPG groups after treatment, the difference of less than two points lacked clinical significance\u003csup\u003e[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]\u003c/sup\u003e. Notably, the pain score of the SPG group improved significantly after treatment, surpassing that of the MPG group. This trend was consistent in jaw function scores, further demonstrating the positive effects of physical therapy on pain improvement.\u003c/p\u003e\u003cp\u003eWhen the baseline data were analysed, no significant differences were found in the mental health levels between the two groups of patients, which was unexpected. It was initially hypothesised that patients with significant pain exhibit lower levels of mental health given the common association of negative emotions\u0026mdash;such as anxiety, depression, somatisation, and catastrophising are often associated\u0026mdash;with more severe pain\u003csup\u003e[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]\u003c/sup\u003e. However, the lack of difference between the two groups does not indicate that both groups of patients are psychologically healthy. Both groups had average PHQ15, PHQ9, and GAD7 scores in the mild-to-moderate range. Previous studies have shown that individuals with TMD generally have lower levels of mental health compared to healthy individuals\u003csup\u003e[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]\u003c/sup\u003e. Therefore, while no difference was found between the two groups in this study, a correlation between psychological effects and TMD symptoms cannot be completely ruled out. To promote symptom recovery, this factor should be considered during treatment. During manual therapy, patients and therapists can communicate fully and exchange detailed information about their diseases, which may help alleviate negative emotions.\u003c/p\u003e\u003cp\u003eThis study has some limitations. Firstly, it primarily focused on patients with ADDWOR who often experienced pain and significant limitations in mouth opening, prompting them to seek hospital treatment. Other subtypes of TMD were not included, such as myofascial pain or clicking with pain. Future research should explore the relationship between pain levels and the treatment needs of other types of patients. Additionally, this study focused only on the treatment and recovery of patients aged 18\u0026thinsp;\u0026minus;\u0026thinsp;45. While TMD is more common in this age group\u003csup\u003e[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]\u003c/sup\u003e, the pain in older age groups may be related to other factors, such as degeneration, leading to higher treatment demands, including drug use and injections. Further exploration should be conducted in this group of people in the future.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eComprehensive physical therapy, a commonly used treatment modality for TMD, can not only alleviate patient pain, improve active mouth opening, and facilitate jaw function but also effectively support their mental health. This study demonstrates that patients with significant pain require more frequent physical therapy.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eADDWOR- Anterior disc displacement without reduction\u003c/p\u003e\n\u003cp\u003eGAD7- Generalised anxiety disorder\u0026nbsp;7\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eJFLS- Jaw Functional Limitation Scale \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMMO- Maximum mouth-opening\u003c/p\u003e\n\u003cp\u003eMPG- Mild pain group\u003c/p\u003e\n\u003cp\u003ePHQ15- Patient health questionnaire\u0026nbsp;15\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePHQ9- Patient health questionnaire\u0026nbsp;9\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSPG- Significant pain group\u003c/p\u003e\n\u003cp\u003eTMD- Temporomandibular joint disorders\u003c/p\u003e\n\u003cp\u003eVAS- Visual analogue scale\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u003c/strong\u003e This study was approved by the Ethics Committee of the Ninth People\u0026rsquo;s Hospital affiliated\u0026nbsp;to\u0026nbsp;Shanghai Jiao Tong University School of Medicine (Approval Number: SH9H-2019-T316). All the patients were aware of the study\u0026rsquo;s purpose and signed an informed consent form before participation, with the option to withdraw at any time.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical Trial Registration:\u0026nbsp;\u003c/strong\u003eChinese Clinical Trial Registry (ChiCTR1800018369).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u003c/strong\u003e Data can be available on reasonable request from the corresponding author.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u003c/strong\u003e The authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e We appreciate the support of relevant funds for this study, which was supported by the Fundamental Research Funds for the Central Universities (YG2024QNA25); Fundamental research program funding of Ninth People\u0026apos;s Hospital affiliated to Shanghai Jiao Tong University School of Medicine (JYZZ229); The Program of Key Supporting Disciplines of Shanghai Health System (2023ZDFC0303); and Special Project for Clinical Research of Health Industry of Shanghai Health Commission (202340129). \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions:\u003c/strong\u003e Yuan Yao contributed to conception, design, data acquisition and interpretation, performed all statistical analyses, and drafted and critically revised the manuscript. Yang Yang and Sha Sha Liu contributed to conception, design, data acquisition, and interpretation. Hong Zeng and Shen Ji Lu contributed to design, performed all statistical analyses, and drafted and critically revised the manuscript. Xin Jiang and Lei Jin contributed to conception, data acquisition, and interpretation. Li Li Xu contributed to conception, design, data acquisition, and interpretation. Bin Cai contributed to conception, design, performed all statistical analyses, and critically revised the manuscript. Zhong Yi Fang: contributed to conception, design, and critically revised the manuscript. All authors read and approved the final version of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u0026nbsp;\u003c/strong\u003eWe would like to express our gratitude to all the patients, interns and departments involved in this study for their unwavering support.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eSchiffman E, Ohrbach R, Truelove E, Look J, Anderson G, Goulet J, et al. Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for Clinical and Research Applications: recommendations of the International RDC/TMD Consortium Network* and Orofacial Pain Special Interest Group. J Oral Facial Pain Headache\u003cem\u003e. \u003c/em\u003e2014;28:6-27.\u003c/li\u003e\n\u003cli\u003eAlrizqi AH, Aleissa BM. Prevalence of temporomandibular disorders between 2015-2021: a literature review. Cureus\u003cem\u003e. \u003c/em\u003e2023;15:e37028.\u003c/li\u003e\n\u003cli\u003eMiernik M, Więckiewicz W. 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Eur J Pain\u003cem\u003e. \u003c/em\u003e2012;15:1061-1067.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Temporomandibular joint disorder, Anterior disc displacement without reduction, Physical therapy, Pain management","lastPublishedDoi":"10.21203/rs.3.rs-6903111/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6903111/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003ePatients with anterior disc displacement without reduction (ADDWOR) frequently experience limited mouth opening and orofacial pain, which has a substantial impact on their quality of life and demands professional assistance. However, the severity of symptoms in patients with ADDWOR varies, especially with different pain levels. Few studies investigate how these variables affect patient efficacy or treatment requirements. Therefore, we evaluated the effectiveness and characteristics of comprehensive physical therapy in patients with ADDWOR at different levels of pain severity.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eThis observational study recruited 91 patients with ADDWOR, and they were divided into two groups based on pain severity: mild pain (n\u0026thinsp;=\u0026thinsp;46) and significant pain (n\u0026thinsp;=\u0026thinsp;45). Comprehensive physical therapy was administered, and the following outcome measures were evaluated before and after treatment: visual analogue scale (VAS) score of pain, maximum mouth opening assessment, jaw functional limitation scale questionnaire, Patient Health Questionnaire 15, Patient Health Questionnaire 9, and generalised anxiety disorder 7. Treatment frequency and duration were also recorded. Independent sample t-tests or Mann\u0026ndash;Whitney U tests were used for intergroup differences, and paired sample t-tests or Mann\u0026ndash;Whitney U tests were used for intragroup differences.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eAfter treatment, no significant differences were found in any of the evaluation indices (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05) between the two groups, except for the VAS and treatment frequency (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Both groups showed significant improvement in all indicators before and after treatment, except for VAS in the mild pain group, which showed no significant change. Comprehensive physical therapy alleviated physical symptoms and positively impacted mental health in patients with ADDWOR and significant pain requiring more frequent treatments.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eComprehensive physical therapy alleviated physical symptoms, such as active mouth opening and pain, and positively affected the mental health of patients with ADDWOR. However, patients with significant pain levels may require more frequent treatments to achieve optimal results.\u003c/p\u003e","manuscriptTitle":"Physical therapy for patients with anterior disc displacement without reduction at different levels of pain: an observational study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-31 15:07:19","doi":"10.21203/rs.3.rs-6903111/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4a405558-fbaf-4b4d-a5e5-37b54e9b2ea7","owner":[],"postedDate":"July 31st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-08-11T11:38:53+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-31 15:07:19","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6903111","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6903111","identity":"rs-6903111","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}