Muscle Relaxation Relieves Post-operative Pain During Hospitalization After Arthroscopic Rotator Cuff Repair—A Retrospective Cohort Study

Muscle Relaxation Relieves Post-operative Pain During Hospitalization After Arthroscopic Rotator Cuff Repair—A Retrospective Cohort 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 Muscle Relaxation Relieves Post-operative Pain During Hospitalization After Arthroscopic Rotator Cuff Repair—A Retrospective Cohort Study Liwei Ying, Junxi Xu, Lijun Zhu, Huixia Fan, Dawei Han, Xiaobo Zhou, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6224614/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Post-operative pain is a major early complication of rotator cuff tear surgery and its management is important for improving patient satisfaction. This study was to compare early post-operative pain severity in patients undergoing rotator cuff repair with or without shoulder muscle relaxation. Methods: A retrospective analysis was performed from January 2022 to June 2022. For group A, which had 178 patients, conservative rehabilitation (only passive forward flexion up to a tolerable range, active elbow flexion and extension) was performed during hospitalization. For group B, which had 196 patients, relaxing shoulder muscle tone was performed on the basis of conservative rehabilitation from the day after surgery. Both resting and locomotor pain scores were recorded before and after operation. Primary outcomes were pain intensity using the numeric rating scale. Results: In general, before and after operation, locomotor pain was more obvious than resting pain in patients. In both groups, levels of post-operative resting pain were increased on the surgical day and on the 1 st post-operative day. Compared to Group A, Group B had lower resting pain scores on the surgical day and on the 1 st post-operative day, and Group B had lower locomotor pain scores on the 1 st and 2 nd post-operative day. In both groups, levels of post-operative resting and locomotor pain were decreased on the 2 nd post-operative day. In addition, Group B used less postoperative additional analgesic. Conclusion : Muscle relaxation is an effective approach for reducing the early post-operative pain after rotator cuff repair during hospitalization. Study Design: Cohort study; Level of evidence, 3. Rotator cuff tears rehabilitation post-operative pain shoulder stiffness muscle stiffness Figures Figure 1 Introduction Rotator cuff tears are common in the general population, particularly among women aged 65–69 years old. It can result in shoulder pain, decreased motor functions and injury of the glenohumeral joint [ 1 , 2 ]. When patients do not respond to non-operative treatment (e.g. physical therapy, local cortisone injection and non-steroidal anti-inflammatory drugs, NSAIDs) or tears exceeding 50% of tendon thickness (tend to evolve into full-thickness rotator cuff tears), surgical repair is recommended [ 3 ]. Post-operative pain is a main early complication after surgery and its management is important for improving patient satisfaction, reducing post-operative complications and decreasing the duration of hospital stay [ 4 ]. Additionally, chronic pain tends to occur in poorly managed acute post-operative pain [ 5 ]. Several factors can lead to early post-operative pain after rotator cuff repair, including preoperative pain and its severity, smaller tear size, younger age, female sex, the performance of an additional subacromial decompression, and pre-existent extensive capsulitis or bursitis [ 6 , 7 ]. However, these factors are not modifiable. Davidson et al. found that an increased amount of passive tension was associated with a significantly high level of post-operative pain [ 8 ]. Post-operative immobilization techniques, such as abduction orthoses and pillows, have been introduced to support the repaired rotator cuffs to reduce tension in repaired tendons. There is still a need to identify other modifiable factors associated with early post-operative pain. Secretion of pro-inflammatory cytokines, such as IL-1, IL-6 and TNFα, is the main event in the inflammatory cascade after surgical trauma [ 9 , 10 ]. This may explain why patients suffer from early post-operative pain after rotator cuff repair and effectiveness of using NSAIDs. Shoulder stiffness is a condition that is characterized by painful reduction of both active and passive ROM and it is known to be a frequent complication of arthroscopic rotator cuff repair [ 10 , 11 ]. Multiple studies have shown that patients with post-operative shoulder stiffness after rotator cuff surgery have higher pain levels [ 12 , 13 ]. And early postoperative pain after arthroscopic rotator cuff surgery is linked to the risk of developing shoulder stiffness [ 14 ]. The above cytokines play a major role in dysregulation of the balance between matrix metalloproteinases and their inhibitors and in inducing phenotypic shifts from fibroblasts to myofibroblasts, leading to development of post-operative shoulder stiffness [ 15 , 16 ]. Capsular fibrosis is the etiology of late shoulder stiffness. In the immediate post-operative period of surgical rotator cuff repair, patients faced with many challenges, including shoulder edema and muscular tension (shrug the operated shoulder continuously or bend the elbow at the surgically affected side). Numerous surgical patients may refrain from moving the surgical site due to worries about post-surgery pain and the possibility of re-injury, leading to shoulder joint stiffness and a subsequent decline in muscle blood circulation, impaired waste removal, reduced nutrient delivery, and leads to pain and muscle fatigue [ 17 ]. Therefore, we surmise that early post-operative shoulder stiffness results from muscle stiffness and muscle rigidity, and post-operative pain can be relieved by relaxing the muscles around the shoulder after rotator cuff repair. Methods Patient selection This study, which was a retrospective analysis of a prospectively collected database, was approved by the Medical Ethics Committee of Taizhou Hospital Affiliated to Wenzhou Medical University (K20221219), and informed written consent was obtained from the patients to publish their medical data. From January 2022 to June 2022, 374 patients received arthroscopic complete RCT repair were included in this study. The inclusion criteria were: patients with small to medium tears. The exclusion criteria were: i. Patients with massive rotator cuff tears (a complete tear of two or more tendons); ii. Patients with acromioclavicular or advanced glenohumeral arthritis; iii. Prior surgery on the affected shoulder; iv. Patients with frozen shoulder or calcific tendinitis. The following demographic characteristics were analyzed: age, sex, laterality, inducements, mean time from symptom onset to operation, diabetes mellitus, hypertension, hyperlipidemia, reduction for shoulder dislocation, periarticular fractures of the shoulder and additional analgesic usage. Operative techniques All RCT repairs were performed by either of two physicians (Xiaobo Zhou and Qingguo Zhang). Briefly, patients were subjected to general anesthesia, and were placed in a lateral decubitus position. The arm was suspended at approximately 45° of abduction and 20° of forward flexion. Diagnostic arthroscopy was then performed to evaluate the extent of RCT, any lesions of the biceps tendon, and other associated lesions. A subacromial decompression, consisting of the release of coracoacromial ligament, subacromial bursectomy, and anteroinferior acromioplasty was performed. The lateral portal was used to mobilize the rotator cuff back to its bony insertion. Using a burr through the lateral portal, the footprint of the greater tuberosity was abraded. Rotator cuff repair was performed by placing one or two rows of suture anchors double-loaded in the lateral aspect of the footprint. The numbers of suture anchors and suture rows varied with the size of the tear, the type of repair techniques and surgeons’ decision. Post-operative rehabilitation Immediately after surgery, the shoulder was placed in a sling. Patients in Group A were subjected to conservative post-operative management with minimal active range of motion of the shoulder. Patients in Group B were subjected to a modified rehabilitation protocol, which was comparable to that of group A, except for additional relaxation of muscles around the shoulder from the day after surgery. 178 patients in group A were subjected to passive assisted shoulder stretching exercises with the limitation of ROM. Passive exercises included only passive forward flexion up to a tolerable range, while passive external rotation exercises and active pendulum exercises were restricted during hospitalization. Besides, active elbow flexion and extension were allowed. Patients were instructed to perform exercises 5 times a day, with 10 repetitions of each movement each time. Each session lasted about 30 min. The arm was supported during rest, using a sling with an abduction pillow [ 18 ]. 196 patients in group B were subjected to the same rehabilitation protocol as those in group A, except for the additional psychoeducation and muscle relaxation therapy just after operation with the support of a physical therapist. The periscapular muscles (including: deltoid, trapezius, levator scapulae, rhomboid, serratus anterior, latissimus dorsi, subscapularis, supraspinatus, infraspinatus, teres major, teres minor, latissimus dorsi), musculus biceps brachii and musculus triceps brachii were massaged 3 times a day. Pre-operative and post-operative evaluations All patients took oral NSAIDs (Celecoxib) after surgery. If the patient is in significant pain and needs additional analgesics, use tramadol, bucinnazine, dezocine, etc.. Pre-operative and post-operative subjective pain scores were measured with the numeric rating scale (NRS) by two nurses. Before resting pain measurements, each patient was asked to not exercise for at least half an hour. Locomotor pain was measured just after shoulder stretching exercises with limitation of ROM. Statistical analysis SPSS software for Windows version 16 (Chicago, Illinois, USA) and the GraphPad Prism software were used for statistical analysis of the data. Descriptive data were reported as mean with standard deviation or number and percentage. Shapiro–Wilk test was used for evaluation of normality of the data. The independent-samples t-test or its nonparametric counterpart (Mann–Whitney U test) was used for comparison of mean values between two independent groups. Theχ2 test was used for evaluation of statistical association between categorical variables. p ≤ 0.05 was set as the threshold for statistical significance. Results A total of 178 patients (male: female, 63:115) were assigned into group A, while 196 patients (male: female, 75:121) were enrolled into group B. The mean age of patients in group A was 59.51 years (range, 41–76), compared with 60.98 (range, 46–96) in group B. Most of the post-operative hospitalization durations were no more than 4 days. Therefore, we collected NRS data across the pre-operative and the 3 post-operative days. There were no significant differences in clinical characteristics between the two groups, except for inducements and postoperative drug use (Table 1 ). Table 1 Clinical characteristics analysis. Bold p values less than 0.05 imply statistically significant differences between groups. Variables Group A (n = 178) Group B (n = 196) p Age 59.51 ± 7.66 60.98 ± 8.56 0.11 Female (%) 115(64.6%) 121(61.7%) 0.97 Laterality (right) 116 133 0.82 Inducements (traumatic) 68 103 0.01 Mean time from symptom onset to operation (month) 4.72 ± 3.51 4.91 ± 4.03 0.67 Diabetes mellitus 16 25 0.28 Hypertension 37 51 0.30 Hyperlipidemia 2 4 0.42 Reduction for shoulder dislocation 3 3 0.99 Periarticular fractures of the shoulder 5 7 0.77 Additional analgesic usage postoperatively 49(27.5%) 23(11.7%) < 0.001 In general, before and after operation, locomotor pain was more obvious than resting pain in patients. In both groups, levels of post-operative resting pain were increased on the surgical day and on the 1st post-operative day, and decreased on the 2nd post-operative day. Compared to Group A, Group B had lower resting pain scores on the surgical day and on the 1st post-operative day. In both groups, levels of post-operative locomotor pain were decreased on the 2nd post-operative day. Compared to Group A, Group B had lower locomotor pain scores on the 1st and 2nd post-operative day (Fig .1). In addition, Group B used less postoperative additional analgesic. Discussion After rotator cuff repair, post-operative pain is very common and it affects patients satisfactory and rehabilitation. This study made a comprehensive assessment of pain severity in two aspects including resting and locomotor pain. We found that muscle relaxation was an effective approach for reducing the early post-operative pain. Based on conservative post-operative rehabilitation procedures after rotator cuff repair, muscle relaxation is a complementary approach for improving patient outcomes. Rehabilitation plays a critical role in achieving satisfactory outcomes after arthroscopic rotator cuff repair and is crucial for successful healing of injured tendons and limiting muscle atrophy. However, the joint motion produced during rehabilitation exercises affects rotator cuff healing because it imparts stresses on repaired rotator cuff tendons, leading to post-operative pain and re-tears [ 19 , 20 ]. In this study, before and after operation, locomotor pain was more obvious than resting pain in patients. Lee et al. [ 21 ] found that the retear rate of the aggressive early passive motion rehabilitation protocol was more than twice the rate of the limited early passive motion rehabilitation group. They concluded that a gentle rehabilitation protocol, with limits in range of motion and exercise times after arthroscopic rotator cuff repair, would be better for tendon healing without taking any substantial risks. The same conclusion was also arrived at by Longo et al. [ 18 ]. They also proved that differences in muscle strength, active and passive ROM as well as clinical scores between the early aggressive rehabilitation protocol and the early limited rehabilitation protocol were not significant after an average follow up of 4 years. Therefore, we adopted a conservative rehabilitation protocol to reduce post-operative locomotor pain and re-tear rate. In rotator cuff repair procedures, shoulder radiofrequency ablation is frequently utilized, and isotonic saline acts as the irrigation fluid for the joint cavity. The shoulder is noticeably swollen after the procedure. The swollen shoulder, the inflammatory response and skin incision may contribute to heightened levels of resting pain on the day of surgery and the first day after surgery. Passive stretch reduces muscle tissue stiffness [ 22 ]. Early passive ROM following arthroscopic cuff repair has been shown to decrease post-operative stiffness and improve functionality [ 23 ]. This may explain that levels of post-operative resting and locomotor pain were decreased on the 2nd post-operative day in both groups. Massage has been applied to relieve pain [ 24 ]. Massage can produce mechanical pressure, which increases muscle compliance by reducing neuro-muscular excitability, resulting in increased range of joint motion as well as decreased passive and active stiffness. In addition, mechanical pressure might help in increasing blood flow by increasing arteriolar pressure, and by increasing muscle temperature from rubbing, which may attenuate inflammation and modulate pain [ 25 ]. Compared to Group A, Group B had lower resting pain scores on the surgical day and on the 1st post-operative day, and Group B had lower locomotor pain scores on the 1st and 2nd post-operative day. Also, Group B used less postoperative additional analgesic. There are several limitations to this study, which is based on long-term clinical observations. We found that most patients were in a compulsive position (continuously shrugged the operated shoulder or bend the elbow at the surgically affected side) after surgery. Muscle stiffness and rigidity were found at the surgically affected side, compared to the contralateral shoulder. However, there was a lack of objective measurement data to value the level of muscle stiffness. Conclusions This study points out that relaxation of shoulder muscles is an effective approach for reducing the early post-operative pain (including resting and locomotor pain) during hospitalization, and may play a guiding role in rehabilitation after rotator cuff repair. Declarations Ethics approval and consent to participate The Medical Ethics Committee of Taizhou Hospital Affiliated to Wenzhou Medical University approved this study (K20221219). All the procedures were conducted according to the Declaration of Helsinki. The need for informed consent was waived by the Medical Ethics Committee of Taizhou Hospital Affiliated to Wenzhou Medical University as the study’s retrospective design. Competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Author contributions Concept/idea/research design: Liwei Ying, Qingguo Zhang Writing and revision: Liwei Ying, Junxi Xu Data collection/ Data analysis: Lijun Zhu, Dawei Han, Huixia Fan Project management: Xiaobo Zhou, Qingguo Zhang Funding Funding for this project was provided by the Basic Public Welfare Research Project of Zhejiang Province (TGY24H060017). Availability of data and materials The datasets generated and analysed during the current study are available from the corresponding author on reasonable request. Acknowledgements Not applicable. References A. Ardeljan, J. Palmer, H. Drawbert, A. Ardeljan, R.M. Vakharia, M.W. 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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-6224614","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":435852479,"identity":"2d464da0-e55b-424a-9e75-c1816c446a2d","order_by":0,"name":"Liwei Ying","email":"","orcid":"","institution":"Taizhou Hospital of Zhejiang Province, Wenzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Liwei","middleName":"","lastName":"Ying","suffix":""},{"id":435852481,"identity":"c66bffd1-9752-4cd1-8da3-152fd3adac3e","order_by":1,"name":"Junxi Xu","email":"","orcid":"","institution":"Taizhou Hospital of Zhejiang Province, Wenzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Junxi","middleName":"","lastName":"Xu","suffix":""},{"id":435852483,"identity":"91771242-b77d-4aa6-8d35-ae87210e2623","order_by":2,"name":"Lijun Zhu","email":"","orcid":"","institution":"Taizhou Hospital of Zhejiang Province, Wenzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Lijun","middleName":"","lastName":"Zhu","suffix":""},{"id":435852484,"identity":"bb40abed-8d1d-467b-a86f-6b7f0e8d9465","order_by":3,"name":"Huixia Fan","email":"","orcid":"","institution":"Taizhou Hospital of Zhejiang Province, Wenzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Huixia","middleName":"","lastName":"Fan","suffix":""},{"id":435852486,"identity":"a8dd39ab-2ba1-4169-bae4-6c1ff7630ef6","order_by":4,"name":"Dawei Han","email":"","orcid":"","institution":"Taizhou Hospital of Zhejiang Province, Wenzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Dawei","middleName":"","lastName":"Han","suffix":""},{"id":435852487,"identity":"b0f276e4-594a-4011-afa5-9361d0a01789","order_by":5,"name":"Xiaobo Zhou","email":"","orcid":"","institution":"Taizhou Hospital of Zhejiang Province, Wenzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Xiaobo","middleName":"","lastName":"Zhou","suffix":""},{"id":435852488,"identity":"27ac410e-f0a5-4348-9df3-bcb3d572f4ec","order_by":6,"name":"Qingguo Zhang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1klEQVRIiWNgGAWjYDACCQglB+UyE6/FmHQtiQ1Ea5Gf3fzs4Zey2vR+6faHj25UWDPwt3cn4NXCOOeYubHMueO5M+ccSDbOOZPOIHHm7Aa8WpglEsykJduO5W64kXBMOrftMIOBRC5+LWwS6d9AWtLtbyS2/879R4QWHokcM8mPbTUJBhLJbMy5DURokZDIKZNmOHfAcMaNNGbpnGPpPAT9Ij8jfZvkj7I6ef4Z6Q8/59RYy/G39+LXAgLMPGyHES4lqBwEGH+w1RGlcBSMglEwCkYoAABo7UXtzDQBDwAAAABJRU5ErkJggg==","orcid":"","institution":"Taizhou Hospital of Zhejiang Province, Wenzhou Medical University","correspondingAuthor":true,"prefix":"","firstName":"Qingguo","middleName":"","lastName":"Zhang","suffix":""}],"badges":[],"createdAt":"2025-03-14 08:38:16","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6224614/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6224614/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":79648223,"identity":"48e92f5c-2fcd-4b41-a9bd-a85eb90d0cc1","added_by":"auto","created_at":"2025-04-01 07:24:29","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":93967,"visible":true,"origin":"","legend":"\u003cp\u003ePre- and post-operative evaluations of resting and locomotor pain in/between groups A and B. # compared with the previous day on the same group, p \u0026lt; 0.05; * compare the two groups on the same day, p \u0026lt; 0.05.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6224614/v1/b16493f973a05564bf6eec1e.png"},{"id":84287689,"identity":"ded6bb27-c993-4c6d-bb5d-50dec392175f","added_by":"auto","created_at":"2025-06-10 08:01:20","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":592120,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6224614/v1/19bee6e5-b591-4a8c-821d-185be6e7509c.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Muscle Relaxation Relieves Post-operative Pain During Hospitalization After Arthroscopic Rotator Cuff Repair—A Retrospective Cohort Study","fulltext":[{"header":"Introduction","content":"\u003cp\u003eRotator cuff tears are common in the general population, particularly among women aged 65\u0026ndash;69 years old. It can result in shoulder pain, decreased motor functions and injury of the glenohumeral joint [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. When patients do not respond to non-operative treatment (e.g. physical therapy, local cortisone injection and non-steroidal anti-inflammatory drugs, NSAIDs) or tears exceeding 50% of tendon thickness (tend to evolve into full-thickness rotator cuff tears), surgical repair is recommended [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Post-operative pain is a main early complication after surgery and its management is important for improving patient satisfaction, reducing post-operative complications and decreasing the duration of hospital stay [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Additionally, chronic pain tends to occur in poorly managed acute post-operative pain [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Several factors can lead to early post-operative pain after rotator cuff repair, including preoperative pain and its severity, smaller tear size, younger age, female sex, the performance of an additional subacromial decompression, and pre-existent extensive capsulitis or bursitis [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, these factors are not modifiable. Davidson et al. found that an increased amount of passive tension was associated with a significantly high level of post-operative pain [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Post-operative immobilization techniques, such as abduction orthoses and pillows, have been introduced to support the repaired rotator cuffs to reduce tension in repaired tendons. There is still a need to identify other modifiable factors associated with early post-operative pain.\u003c/p\u003e \u003cp\u003eSecretion of pro-inflammatory cytokines, such as IL-1, IL-6 and TNFα, is the main event in the inflammatory cascade after surgical trauma [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. This may explain why patients suffer from early post-operative pain after rotator cuff repair and effectiveness of using NSAIDs. Shoulder stiffness is a condition that is characterized by painful reduction of both active and passive ROM and it is known to be a frequent complication of arthroscopic rotator cuff repair [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Multiple studies have shown that patients with post-operative shoulder stiffness after rotator cuff surgery have higher pain levels [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. And early postoperative pain after arthroscopic rotator cuff surgery is linked to the risk of developing shoulder stiffness [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. The above cytokines play a major role in dysregulation of the balance between matrix metalloproteinases and their inhibitors and in inducing phenotypic shifts from fibroblasts to myofibroblasts, leading to development of post-operative shoulder stiffness [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Capsular fibrosis is the etiology of late shoulder stiffness. In the immediate post-operative period of surgical rotator cuff repair, patients faced with many challenges, including shoulder edema and muscular tension (shrug the operated shoulder continuously or bend the elbow at the surgically affected side). Numerous surgical patients may refrain from moving the surgical site due to worries about post-surgery pain and the possibility of re-injury, leading to shoulder joint stiffness and a subsequent decline in muscle blood circulation, impaired waste removal, reduced nutrient delivery, and leads to pain and muscle fatigue [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Therefore, we surmise that early post-operative shoulder stiffness results from muscle stiffness and muscle rigidity, and post-operative pain can be relieved by relaxing the muscles around the shoulder after rotator cuff repair.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatient selection\u003c/h2\u003e \u003cp\u003e This study, which was a retrospective analysis of a prospectively collected database, was approved by the Medical Ethics Committee of Taizhou Hospital Affiliated to Wenzhou Medical University (K20221219), and informed written consent was obtained from the patients to publish their medical data. From January 2022 to June 2022, 374 patients received arthroscopic complete RCT repair were included in this study. The inclusion criteria were: patients with small to medium tears. The exclusion criteria were: i. Patients with massive rotator cuff tears (a complete tear of two or more tendons); ii. Patients with acromioclavicular or advanced glenohumeral arthritis; iii. Prior surgery on the affected shoulder; iv. Patients with frozen shoulder or calcific tendinitis.\u003c/p\u003e \u003cp\u003eThe following demographic characteristics were analyzed: age, sex, laterality, inducements, mean time from symptom onset to operation, diabetes mellitus, hypertension, hyperlipidemia, reduction for shoulder dislocation, periarticular fractures of the shoulder and additional analgesic usage.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eOperative techniques\u003c/h3\u003e\n\u003cp\u003eAll RCT repairs were performed by either of two physicians (Xiaobo Zhou and Qingguo Zhang). Briefly, patients were subjected to general anesthesia, and were placed in a lateral decubitus position. The arm was suspended at approximately 45\u0026deg; of abduction and 20\u0026deg; of forward flexion. Diagnostic arthroscopy was then performed to evaluate the extent of RCT, any lesions of the biceps tendon, and other associated lesions. A subacromial decompression, consisting of the release of coracoacromial ligament, subacromial bursectomy, and anteroinferior acromioplasty was performed. The lateral portal was used to mobilize the rotator cuff back to its bony insertion. Using a burr through the lateral portal, the footprint of the greater tuberosity was abraded. Rotator cuff repair was performed by placing one or two rows of suture anchors double-loaded in the lateral aspect of the footprint. The numbers of suture anchors and suture rows varied with the size of the tear, the type of repair techniques and surgeons\u0026rsquo; decision.\u003c/p\u003e\n\u003ch3\u003ePost-operative rehabilitation\u003c/h3\u003e\n\u003cp\u003eImmediately after surgery, the shoulder was placed in a sling. Patients in Group A were subjected to conservative post-operative management with minimal active range of motion of the shoulder. Patients in Group B were subjected to a modified rehabilitation protocol, which was comparable to that of group A, except for additional relaxation of muscles around the shoulder from the day after surgery.\u003c/p\u003e \u003cp\u003e178 patients in group A were subjected to passive assisted shoulder stretching exercises with the limitation of ROM. Passive exercises included only passive forward flexion up to a tolerable range, while passive external rotation exercises and active pendulum exercises were restricted during hospitalization. Besides, active elbow flexion and extension were allowed. Patients were instructed to perform exercises 5 times a day, with 10 repetitions of each movement each time. Each session lasted about 30 min. The arm was supported during rest, using a sling with an abduction pillow [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e196 patients in group B were subjected to the same rehabilitation protocol as those in group A, except for the additional psychoeducation and muscle relaxation therapy just after operation with the support of a physical therapist. The periscapular muscles (including: deltoid, trapezius, levator scapulae, rhomboid, serratus anterior, latissimus dorsi, subscapularis, supraspinatus, infraspinatus, teres major, teres minor, latissimus dorsi), musculus biceps brachii and musculus triceps brachii were massaged 3 times a day.\u003c/p\u003e\n\u003ch3\u003ePre-operative and post-operative evaluations\u003c/h3\u003e\n\u003cp\u003eAll patients took oral NSAIDs (Celecoxib) after surgery. If the patient is in significant pain and needs additional analgesics, use tramadol, bucinnazine, dezocine, etc.. Pre-operative and post-operative subjective pain scores were measured with the numeric rating scale (NRS) by two nurses. Before resting pain measurements, each patient was asked to not exercise for at least half an hour. Locomotor pain was measured just after shoulder stretching exercises with limitation of ROM.\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eSPSS software for Windows version 16 (Chicago, Illinois, USA) and the GraphPad Prism software were used for statistical analysis of the data. Descriptive data were reported as mean with standard deviation or number and percentage. Shapiro\u0026ndash;Wilk test was used for evaluation of normality of the data. The independent-samples t-test or its nonparametric counterpart (Mann\u0026ndash;Whitney U test) was used for comparison of mean values between two independent groups. Theχ2 test was used for evaluation of statistical association between categorical variables. p\u0026thinsp;\u0026le;\u0026thinsp;0.05 was set as the threshold for statistical significance.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 178 patients (male: female, 63:115) were assigned into group A, while 196 patients (male: female, 75:121) were enrolled into group B. The mean age of patients in group A was 59.51 years (range, 41\u0026ndash;76), compared with 60.98 (range, 46\u0026ndash;96) in group B. Most of the post-operative hospitalization durations were no more than 4 days. Therefore, we collected NRS data across the pre-operative and the 3 post-operative days. There were no significant differences in clinical characteristics between the two groups, except for inducements and postoperative drug use (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\u003eClinical characteristics analysis. Bold p values less than 0.05 imply statistically significant differences between groups.\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 \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGroup A (n\u0026thinsp;=\u0026thinsp;178)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eGroup B (n\u0026thinsp;=\u0026thinsp;196)\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\u003eAge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e59.51\u0026thinsp;\u0026plusmn;\u0026thinsp;7.66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e60.98\u0026thinsp;\u0026plusmn;\u0026thinsp;8.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.11\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\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e115(64.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e121(61.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLaterality (right)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e116\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e133\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.82\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInducements (traumatic)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e103\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean time from symptom onset to operation (month)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e4.72\u0026thinsp;\u0026plusmn;\u0026thinsp;3.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.91\u0026thinsp;\u0026plusmn;\u0026thinsp;4.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.67\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiabetes mellitus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.28\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypertension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHyperlipidemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.42\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReduction for shoulder dislocation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePeriarticular fractures of the shoulder\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.77\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAdditional analgesic usage postoperatively\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e49(27.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e23(11.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\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 \u003c/p\u003e \u003cp\u003eIn general, before and after operation, locomotor pain was more obvious than resting pain in patients. In both groups, levels of post-operative resting pain were increased on the surgical day and on the 1st post-operative day, and decreased on the 2nd post-operative day. Compared to Group A, Group B had lower resting pain scores on the surgical day and on the 1st post-operative day. In both groups, levels of post-operative locomotor pain were decreased on the 2nd post-operative day. Compared to Group A, Group B had lower locomotor pain scores on the 1st and 2nd post-operative day (Fig .1). In addition, Group B used less postoperative additional analgesic.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eAfter rotator cuff repair, post-operative pain is very common and it affects patients satisfactory and rehabilitation. This study made a comprehensive assessment of pain severity in two aspects including resting and locomotor pain. We found that muscle relaxation was an effective approach for reducing the early post-operative pain. Based on conservative post-operative rehabilitation procedures after rotator cuff repair, muscle relaxation is a complementary approach for improving patient outcomes.\u003c/p\u003e \u003cp\u003eRehabilitation plays a critical role in achieving satisfactory outcomes after arthroscopic rotator cuff repair and is crucial for successful healing of injured tendons and limiting muscle atrophy. However, the joint motion produced during rehabilitation exercises affects rotator cuff healing because it imparts stresses on repaired rotator cuff tendons, leading to post-operative pain and re-tears [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. In this study, before and after operation, locomotor pain was more obvious than resting pain in patients. Lee et al. [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] found that the retear rate of the aggressive early passive motion rehabilitation protocol was more than twice the rate of the limited early passive motion rehabilitation group. They concluded that a gentle rehabilitation protocol, with limits in range of motion and exercise times after arthroscopic rotator cuff repair, would be better for tendon healing without taking any substantial risks. The same conclusion was also arrived at by Longo et al. [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. They also proved that differences in muscle strength, active and passive ROM as well as clinical scores between the early aggressive rehabilitation protocol and the early limited rehabilitation protocol were not significant after an average follow up of 4 years. Therefore, we adopted a conservative rehabilitation protocol to reduce post-operative locomotor pain and re-tear rate.\u003c/p\u003e \u003cp\u003eIn rotator cuff repair procedures, shoulder radiofrequency ablation is frequently utilized, and isotonic saline acts as the irrigation fluid for the joint cavity. The shoulder is noticeably swollen after the procedure. The swollen shoulder, the inflammatory response and skin incision may contribute to heightened levels of resting pain on the day of surgery and the first day after surgery. Passive stretch reduces muscle tissue stiffness [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Early passive ROM following arthroscopic cuff repair has been shown to decrease post-operative stiffness and improve functionality [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. This may explain that levels of post-operative resting and locomotor pain were decreased on the 2nd post-operative day in both groups. Massage has been applied to relieve pain [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Massage can produce mechanical pressure, which increases muscle compliance by reducing neuro-muscular excitability, resulting in increased range of joint motion as well as decreased passive and active stiffness. In addition, mechanical pressure might help in increasing blood flow by increasing arteriolar pressure, and by increasing muscle temperature from rubbing, which may attenuate inflammation and modulate pain [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Compared to Group A, Group B had lower resting pain scores on the surgical day and on the 1st post-operative day, and Group B had lower locomotor pain scores on the 1st and 2nd post-operative day. Also, Group B used less postoperative additional analgesic.\u003c/p\u003e \u003cp\u003eThere are several limitations to this study, which is based on long-term clinical observations. We found that most patients were in a compulsive position (continuously shrugged the operated shoulder or bend the elbow at the surgically affected side) after surgery. Muscle stiffness and rigidity were found at the surgically affected side, compared to the contralateral shoulder. However, there was a lack of objective measurement data to value the level of muscle stiffness.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThis study points out that relaxation of shoulder muscles is an effective approach for reducing the early post-operative pain (including resting and locomotor pain) during hospitalization, and may play a guiding role in rehabilitation after rotator cuff repair.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Medical Ethics Committee of Taizhou Hospital Affiliated to Wenzhou Medical University approved this study (K20221219). All the procedures were conducted according to the Declaration of Helsinki. The need for informed consent was waived by the Medical Ethics Committee of Taizhou Hospital Affiliated to Wenzhou Medical University as the study’s retrospective design.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConcept/idea/research design: Liwei Ying, Qingguo Zhang\u003c/p\u003e\n\u003cp\u003eWriting and revision: Liwei Ying, Junxi Xu\u003c/p\u003e\n\u003cp\u003eData collection/ Data analysis: Lijun Zhu, Dawei Han, Huixia Fan\u003c/p\u003e\n\u003cp\u003eProject management: Xiaobo Zhou, Qingguo Zhang\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFunding for this project was provided by the Basic Public Welfare Research Project of Zhejiang Province (TGY24H060017).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated and analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eA. 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Feroldi, A. De Silvestri, M.J. Friedrich, M.D. Wimmer, P.S. Randelli, Treatment of partial rotator cuff lesions is associated with a higher frequency of post-operative shoulder stiffness. A prospective investigation on the role of surgery-related risk factors for this complication, Arch Orthop Trauma Surg (2021).\u003c/li\u003e\n\u003cli\u003eE. Itoi, G. Arce, G.I. Bain, R.L. Diercks, D. Guttmann, A.B. Imhoff, A.D. Mazzocca, H. Sugaya, Y.S. Yoo, Shoulder Stiffness: Current Concepts and Concerns, Arthroscopy : the journal of arthroscopic \u0026amp; related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association 32(7) (2016) 1402-14.\u003c/li\u003e\n\u003cli\u003eS.W. Chung, C.B. Huong, S.H. Kim, J.H. Oh, Shoulder stiffness after rotator cuff repair: risk factors and influence on outcome, Arthroscopy : the journal of arthroscopic \u0026amp; related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association 29(2) (2013) 290-300.\u003c/li\u003e\n\u003cli\u003eK. Trenerry, J.R. Walton, G.A. Murrell, Prevention of shoulder stiffness after rotator cuff repair, Clinical orthopaedics and related research (430) (2005) 94-9.\u003c/li\u003e\n\u003cli\u003eM.R. Guity, A. Sobhani Eraghi, F.S. Hosseini-Baharanchi, Early postoperative pain as a risk factor of shoulder stiffness after arthroscopic rotator cuff repair, Journal of orthopaedics and traumatology : official journal of the Italian Society of Orthopaedics and Traumatology 22(1) (2021) 25.\u003c/li\u003e\n\u003cli\u003eD. Cucchi, A. Marmotti, S. De Giorgi, A. Costa, R. D\u0026apos;Apolito, M. Conca, A. Russo, M.F. Saccomanno, L. de Girolamo, Risk Factors for Shoulder Stiffness: Current Concepts, Joints 5(4) (2017) 217-223.\u003c/li\u003e\n\u003cli\u003eJ.-Y. Ko, W.-S. Lian, T.-C. Tsai, Y.-S. Chen, C.-K. Hsieh, C.-W. Kuo, F.-S. Wang, MicroRNA-29a Mitigates Subacromial Bursa Fibrosis in Rotator Cuff Lesion with Shoulder Stiffness, International Journal of Molecular Sciences 20(22) (2019).\u003c/li\u003e\n\u003cli\u003eD. Yi, H. Lim, J. Yim, Effect of Microcurrent Stimulation on Pain, Shoulder Function, and Grip Strength in Early Post-Operative Phase after Rotator Cuff Repair, Medicina (Kaunas, Lithuania) 57(5) (2021).\u003c/li\u003e\n\u003cli\u003eU.G. Longo, G. Rizzello, S. Petrillo, M. Loppini, N. Maffulli, V. Denaro, Conservative Rehabilitation Provides Superior Clinical Results Compared to Early Aggressive Rehabilitation for Rotator Cuff Repair: A Retrospective Comparative Study, Medicina (Kaunas) 55(8) (2019).\u003c/li\u003e\n\u003cli\u003eJ.L. West, J.S. Keene, L.D. Kaplan, Early motion after quadriceps and patellar tendon repairs: outcomes with single-suture augmentation, Am J Sports Med 36(2) (2008) 316-23.\u003c/li\u003e\n\u003cli\u003eL.M. Galatz, N. Charlton, R. Das, H.M. Kim, N. Havlioglu, S. Thomopoulos, Complete removal of load is detrimental to rotator cuff healing, J Shoulder Elbow Surg 18(5) (2009) 669-75.\u003c/li\u003e\n\u003cli\u003eB.G. Lee, N.S. Cho, Y.G. Rhee, Effect of two rehabilitation protocols on range of motion and healing rates after arthroscopic rotator cuff repair: aggressive versus limited early passive exercises, Arthroscopy : the journal of arthroscopic \u0026amp; related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association 28(1) (2012) 34-42.\u003c/li\u003e\n\u003cli\u003eD.A. Riley, J.M. Van Dyke, The effects of active and passive stretching on muscle length, Physical medicine and rehabilitation clinics of North America 23(1) (2012) 51-7, x.\u003c/li\u003e\n\u003cli\u003eO. Nikolaidou, S. Migkou, C. Karampalis, Rehabilitation after Rotator Cuff Repair, The open orthopaedics journal 11 (2017) 154-162.\u003c/li\u003e\n\u003cli\u003eP. Weerapong, P.A. Hume, G.S. Kolt, The mechanisms of massage and effects on performance, muscle recovery and injury prevention, Sports medicine (Auckland, N.Z.) 35(3) (2005) 235-56.\u003c/li\u003e\n\u003cli\u003eM.T. Loghmani, C. Tobin, C. Quigley, A. Fennimore, Soft Tissue Manipulation May Attenuate Inflammation, Modulate Pain, and Improve Gait in Conscious Rodents With Induced Low Back Pain, Mil Med 186(Suppl 1) (2021) 506-514.\u003c/li\u003e\n\u003cli\u003eM. Salas, B. Zaldivar, G. Fierro, J.C. Gonzalez, J.R. Lievano, Incidence and risk factors for shoulder stiffness after open and arthroscopic rotator cuff repair, Archives of orthopaedic and trauma surgery 144(5) (2024) 2047-2055.\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":"Rotator cuff tears, rehabilitation, post-operative pain, shoulder stiffness, muscle stiffness","lastPublishedDoi":"10.21203/rs.3.rs-6224614/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6224614/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003ePost-operative pain is a major early complication of rotator cuff tear surgery and its management is important for improving patient satisfaction. This study was to compare early post-operative pain severity in patients undergoing rotator cuff repair with or without shoulder muscle relaxation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eA retrospective analysis was performed from January 2022 to June 2022. For group A, which had 178 patients, conservative rehabilitation (only passive forward flexion up to a tolerable range, active elbow flexion and extension) was performed during hospitalization. For group B, which had 196 patients, relaxing shoulder muscle tone was performed on the basis of conservative rehabilitation from the day after surgery. Both resting and locomotor pain scores were recorded before and after operation. Primary outcomes were pain intensity using the numeric rating scale.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e In general, before and after operation, locomotor pain was more obvious than resting pain in patients. In both groups, levels of post-operative resting pain were increased on the surgical day and on the 1\u003csup\u003est\u003c/sup\u003e post-operative day. Compared to Group A, Group B had lower resting pain scores on the surgical day and on the 1\u003csup\u003est\u003c/sup\u003e post-operative day, and Group B had lower locomotor pain scores on the 1\u003csup\u003est\u003c/sup\u003e and 2\u003csup\u003end\u003c/sup\u003e post-operative day. In both groups, levels of post-operative resting and locomotor pain were decreased on the 2\u003csup\u003end \u003c/sup\u003epost-operative day. In addition, Group B used less postoperative additional analgesic.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e: Muscle relaxation is an effective approach for reducing the early post-operative pain after rotator cuff repair during hospitalization.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStudy Design:\u003c/strong\u003e Cohort study; Level of evidence, 3.\u003c/p\u003e","manuscriptTitle":"Muscle Relaxation Relieves Post-operative Pain During Hospitalization After Arthroscopic Rotator Cuff Repair—A Retrospective Cohort Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-01 07:24:25","doi":"10.21203/rs.3.rs-6224614/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":"ad6972c7-2538-425e-b422-7fb7400275b9","owner":[],"postedDate":"April 1st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-10T07:53:13+00:00","versionOfRecord":[],"versionCreatedAt":"2025-04-01 07:24:25","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6224614","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6224614","identity":"rs-6224614","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}