Triangular Forearm Support in Rotator Cuff Syndrome a randomized crossover trial with EMG insight into mechanism of action

Triangular Forearm Support in Rotator Cuff Syndrome a randomized crossover trial with EMG insight into mechanism of action | 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 Triangular Forearm Support in Rotator Cuff Syndrome a randomized crossover trial with EMG insight into mechanism of action Loren Fishman, Bernard Rosner This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7895251/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract Design: Randomized blinded control crossover of yoga-like maneuver treating MRI confirmed rotator cuff syndrome (RCS); minimum 29-month follow-up. Patient selection : RCS pain >5/10 on visual analogue scale (VAS). Intervention (80) and placebo (87) groups. Intervention : Triangular forearm support (TFS). Main outcome measures : VAS, shoulder kinetics. Methods : Patient-rated abduction and flexion pain pre – and post – TFS, and multi-channel EMG. Results : Intervention group: Abduction: mean post-TFS and post-placebo VAS dropped 1.98 and 1.08 points from 6.14 and 5.03 respectively or 32.3% vs. 21%, respectively. Flexion: baseline intervention group values: 5.13 and 4.57 dropped 1.08 and .93 points, 32% and 20.4% lower, respectively. (p =.002; p <.008). Placebo group’s crossover post TFS: mean abduction and flexion VAS dropped 1.25 and 1.39 respectively. All tests: p < .001. Mean 52-month follow-up for all patients: abduction and flexion VAS: mean improvement from initial post-TFS VAS: 0.92 points (95% CI: 0.13 to 1.71), p = 0.02 and 1.13 points (95% CI 0.54 - 1.73), p <0.001) respectively. VAS values for abduction and flexion were 67.6% and 74.5% below baseline. Post-TFS EMG of abduction showed greater activation of the subscapularis, less in deltoid, suggesting cantilevering the humerus upward between 80 – 110 degrees. Conclusion: The TFS maneuver may be helpful in RCS by employing a cantilever mechanism in abduction and flexion. Rotator cuff syndrome Triangular forearm support Kinesiology Yoga Cantilever EMG Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 What is already known A protracted course of conservative therapy can rehabilitate people with partial tear rotator cuff syndrome (RCS) non-inferiorly to surgical intervention, but conservative therapy is inferior to surgical intervention in full thickness tears. What this study adds: Triangular forearm support is a conservative method that reduces RCS pain in 2.5-year follow-up with kinesiological alterations independent of the severity of the tear. How might this affect clinical thought and practice? In the clinic, a practical and innocuous treatment of RCS has immediate benefits for the patients, the clinicians and the health care system. In research, an example of beneficially altered shoulder kinetics might inspire other research toward similar beneficial alterations. Successful use of this maneuver might effect changes in emphasis for research funding policy and the best practices policy for clinical interventions. Introduction Rotator cuff syndrome is one of the most common orthopedic injuries of the upper extremities, with biphasic incidence peaks at 35 and 55 years of age. 1-3 Cadaveric studies find nearly 50% of individuals over 80 years of age have significant rotator cuff tears. 1,2 Although ultrasound is often diagnostic, MRI is still the most reliable means of making the diagnosis. 4-6 Surgery has been more successful with chronic and acute tears than conservative therapy 7 as currently administered. More than 10% of conservatively treated RCS patients progress to surgery 8,9 and then to physical therapy, although conservative means are not inferior to arthroscopic interventions 7 with respect to pain in smaller tears. Recovery of strength after conservative methods is debatable, 8,9 but generally found inferior to post-surgical recovery. 10,11 Full recovery after surgery takes seven to ten months and is painful and costly. A more effective conservative treatment would be welcome. Our objective was to determine if an isometric yoga-like maneuver could relieve the symptoms of RCS in the long term, and to examine the shoulder kinetics it utilizes. The supraspinatus muscle is torn in 90% of RCS, 3 rendering abduction and flexion to 90 degrees very painful or frankly impossible. At this angle the deltoid’s fibers are pulling horizontally, without a vertical component; abduction and flexion within the 80 – 110-degree range therefore depend on the supraspinatus and to a lesser extent, the infraspinatus. When the supraspinatus is torn or divided, abduction and flexion become problematical: these motions are painful in the case of a tear and seemingly impossible if the supraspinatus is transected. Figure 1: We serendipitously found a yoga maneuver, the triangular forearm support (TFS) that seemed to accomplish this task and tested it in a non-randomized study. 12 See figure 1. This paper reports a randomized controlled test of its utility and secondarily probes both the mechanism by which it may succeed, and the longevity of the improvement. Methods The study took place in private offices in Manhattan.Research reported in this publication was supported in part by the National Institute of Nursing Research of the National Institutes of Health under Awards Number R21NR016510, and conducted between April 6, 2021 and December 24, 2022, after a suspension due to the COVID-19 pandemic. The study was approved by the CIRBI IRB, now Advarra, and first submitted to Clinical Trials.gov, on April 6, 2021 and first posted on April 7, 2021. It is listed as NCT04833244. Inclusion criteria: MRI confirmation of partial or full-thickness tear of the supraspinatus muscle or its tendon. Self-rated pain in abduction or flexion equal to or above 5/10 on the visual analogue scale (VAS). Exclusion criteria: Previous ipsilateral shoulder surgery. Neuromuscular conditions such as amyotrophic lateral sclerosis, cerebrovascular accident, or cerebral palsy affecting the ipsilateral shoulder. Self-rated pain in abduction and flexion below 5/10 on the VAS. After signing the Informed Consent forms, selected patients were randomized using random.com. Participants were blinded to their assignment into intervention (IG) or control groups (CG). Bilateral abduction and flexion with straight elbows were performed by both IG and CG three times (three maximal shoulder abductions followed by three maximal shoulder flexions) both before and after the TFS maneuver was taught. See figure 1. The examiner displayed each movement before the subject was asked to do it. Immediately following each abduction and each flexion, the subject stated his or her assessment of the most intense pain felt during that action on a 0-10 VAS scale. The examiner recorded these values. Full silence was maintained, apart from the verbal report of maximal pain felt by the subject. After three abductions and flexions, the IG patients were taught TFS, and the CG patients were taught a sham procedure. The abductions and flexions were then repeated for all patients with the same pain-scale rating procedure as before. At this point the intervention-group patients were finished with the study, except for the years-later follow-up. The sham-group patients were taught TFS immediately after the second rating, followed by a third series of flexion and abduction with VAS rating. See figure 2. Figure 2: Follow-up was sought in up to three emails and three phone calls. Due to the COVID pandemic follow-up times were significantly increased. Mean follow-up time was 52 months; range 29 – 60 months. Participants were asked to rate their pain with abduction and flexion, along with any relevant mishaps or treatment or relevant medications they encountered in the interim. Details of the procedure: The TFS maneuver consists of folding one’s hands with palms together and placing the forearms against a wall with head in the center of the triangle made by the forearms, then pulling the shoulders away from the wall until the superior third of the trapezius and the supraspinatus become soft. For an example of the TFS maneuver, readers are referred to the video on You Tube: https://www.youtube.com/watch?v=jzOsaE0Kyq8 Activation of the subscapularis was gauged by means of the agonist-antagonist reflex: We worked with the patient until the supraspinatus and superior 1/3 of the trapezius were relaxed, indicating that the subscapularis was active. We did this by palpating these muscles just rostral to the scapular spine. Control group participants were asked to interdigitate their hands in front of themselves with elbows straight and hold the position for 45 seconds. Immediately after performing the TFS maneuver or placebo maneuver for 45 seconds, patients were encouraged to “bravely, boldly, fearlessly” maximally abduct their arms three times and then flex their shoulders three times with elbows straight. These maneuvers were verbally rated on the VAS reflecting the maximum pain felt with each abduction and each flexion. The examiner recorded the participants’ maximal pain responses to the abductions and flexions on a score sheet. The demographic and study data used to support the findings of this study have been deposited in the Columbia University Academic repository: Academic [email protected] . https://doi.org/10.7916/5xps-y460 Statistical approach: The three pre-maneuver (or placebo) abduction and three pre-intervention (or placebo) flexion scores given by the subjects were averaged separately, and differences between the pre- and post-maneuver or post-placebo scores were sought. The power calculations for this paper involved alpha of .05 and power of 80%, and the assumption that the placebo group would differ from the intervention group by 25%. This assumption was based on an earlier paper studying the maneuver. 12 This study used t-tests and Wilcoxon rank sum tests. These tests were paired or unpaired as appropriate. We also used paired t-tests to compare abduction and flexion pain scores post-intervention with abduction and flexion pain at follow-up using the survey questions “On a scale of 0-10, how much pain do you feel now lifting that arm to the side ?", and "On a scale of 0-10, much pain do you feel now lifting that arm out in front of you?" respectively. We averaged pain across the two arms for subjects who had RCS in both shoulders. Results 212 patients were recruited, of which 167 completed the procedure properly. There were 80 intervention and 87 control-plus-crossover patients with mean age of 64.52 years. See table 1. No patients were lost to the immediate follow-up since the single assessment immediately followed the intervention and placebo maneuvers. Mean intervention patients’ pain scores for abduction and flexion were immediately reduced from 6.14 and 5.13, respectively by 1.98 and 1.64 points (CI: .0526; .0438) respectively, a reduction of 32.3% and 32.0 %. In contrast, mean sham patients’ pain scores for abduction and flexion were reduced from 5.03 and 4.57 by 1.08 and .93 points, (CI: .0513; .0357), 21.5% and 21.4%, respectively. T-test values for patients’ pain scores for abduction and flexion were p < .002 and p < .008 respectively, and Wilcoxon rank sum test values were p < .004 and p < .002 respectively in IG vs. CG. When the CG patients were given TFS immediately thereafter, their mean VAS scores were reduced by 1.25 and 1.39 for abduction and flexion (CI: ±.378; ±.340) or 24.9% and 28.2% respectively. See table 2. We also recorded whether the tears were full thickness or partial thickness, and whether they were in dominant or non-dominant arm. The effect of TFS was not significantly different when grouped by nature of the tear of the supraspinatus or infraspinatus. See table 3. Also, the differences in outcomes where the dominant vs. non-dominant upper extremity was affected were insignificant. The 3-year clinical effort abruptly came to an end on March 13, 2020 with the COVID-19 pandemic being declared a national emergency. Seventy-three patients responded to the mean 52 months’ post-intervention inquiries. Mean 52 months’ follow-up found that 3 patients had required surgery, 3 had platelet rich plasma injections and 13 of the 73 responding patients received further physical therapy. Since the CG patients were shown the TFS maneuver immediately after their post-placebo testing, there were no controls for the long-range follow-up. However, we sought changes in the combined IG + CG patients for long-term follow-up, since at that point all subjects had had the TFS maneuver. Of the 54 patients without confounding events or further treatment, abduction VAS scores for flexion and abduction were 1.53 and 1.04 (SD 2.50; 2.25) respectively as compared with study-start values of 6.14 and 5.13, giving improvement of 75.6% and 75.6% respectively. See table 4. The 54 unconfounded subjects’ abduction pain decreased from a mean of 2.45 (SD=2.34) post-intervention to 1.53 (SD=2.28) at follow-up a mean improvement of 0.92 points (95% CI 0.13 to 1.71), p=0.02). These patients’ flexion pain decreased from a mean of 2.17 (SD=2.26) post-intervention to 1.04 (1.79) at follow-up, a mean improvement of 1.13 points (95% CI 0.54 to 1.73), p<0.001). See table 5 and figure 3. Adverse effects: One patient who did not improve complained of significant pain following TFS. She refused MRI or other follow-up. Apart from this no adverse side effects from the procedure were noted. Better to understand how the TFS initiated this rapid change in function, and relate the anatomy and kinesiology to clinical reality, we studied the TFS maneuver with 8 channel EMG. Monopolar 37 mm needle electrodes and reference electrodes were placed in the supraspinatus, infraspinatus, deltoid, rhomboid major, pectoralis, serratus anterior, teres minor and latissimus dorsi muscles, with ground on the sternum, using a Sierra Wave II electrodiagnostic device set at 100 microvolts and 10 ms per division. One subject abducted repeatedly in this montage. The subject had had RCS surgery for a partial tear in his right shoulder ten years earlier, and an untreated massive tear on the left in which the supraspinatus muscle was wholly divided into two fragments.2.5 cm apart. This shoulder was treated with TFS. In the post-surgical EMG the right supraspinatus began acting at 80 degrees, as the deltoid’s fibres approached horizontal. This is what normally happens in people’ shoulders that do not have RCS. But post TFS, the left supraspinatus showed early activity that did not change at 80 degrees; it was not the abducting force here. In the TFS arm a spindle of subscapularis activity begins at 80 degrees and is evidence that the subscapularis took up the abduction function previously assumed by the supraspinatus at 80 degrees. The amplitude of the TFS side’s deltoid activity decreased in the range of 80 – 110 degrees, suggesting that it functioned to stabilize the proximal humeral shaft, acting from above the humerus as a fulcrum as the subscapularis’ contraction cantilevered the distal shaft of the humerus upward. The subscapularis, with its attachment closer to the humeral head, pulled the humeral head downward, which cantilevered its more distal shaft upward. See figures 1, 3, 4. Figure 3: The rhomboides and pectoralis muscles were activated in tandem in both the surgical and TFS arms: both dorsal and ventral pressures from these muscles have an inferior pointed vector that can sum to stabilize the scapula and aid the work of the functioning right subscapularis, with which they were simultaneously activated. Summary of kinetics of abduction/flexion after TFS While the subscapularis cantilevers the humerus from 80 -110 degrees; the supraspinatus, in this case massively torn, had no part in the action, with just mild continuous activity throughout abduction. The subscapularis’ EMG record denotes heightened activity exactly between 80 and 110 degrees, where the deltoid’s effect on abduction and flexion is virtually null. This principle was supported by the lack of relationship between the severity of the tear (more than 50% vs. less than 50%) and the degree of improvement in pain. The efficacy of TFS with full as well as partial tears suggests that the maneuver does not particularly depend on strength, but rather replacing a torn muscle’s function with another muscle used in a different way, but with similar results. See table 3. Discussion The improvement with TFS is significant in the academic sense but is it clinically significant.? Farrar, et. al. 13 point out that gaining points on a Likert-type scale may have very different clinical impact but state that a reduction of 2 points or 30% is generally clinically significant. To this end we have included the initial scores, which lie in the middle range: 5 – 6/10. See table 2. People’s pain levels improved 75.6% over the years between study entry and follow-up. See table 4 and figure 4. Figure 5: The more than ¾ overall mean improvement over the follow-up period might be attributable to slow healing that would occur naturally over four years. However, the natural history of untreated RCS is that it worsens over time. 14,15 Therefore it is likely that TFS is a significant factor in patients’ improvement. Strategic use of TFS The clinical significance of this maneuver, however, depends on its longevity. A previous study followed 50 patients for 30 months and found that 94% of the patients doubled their flexion and abduction ranges and reduced their pain more than 80% throughout that time span. 12 In that study most patients repeated the TFS maneuver daily for a few weeks, but then the shoulder stayed painlessly high functioning without further intervention for the 30 months for which they were studied. In this study we used telephone, email and Zoom to communicate with patients years after the initial intervention. See figure 5. Figure 6 The long-lasting effect of TFS may be a case of muscle re-learning, or operant conditioning, 16 a non-conscious adaptation in which patients spontaneously choose the painless cantilevering action of the subscapularis for abducting and flexing the shoulder over the otherwise ineffective and painful use of the torn supraspinatus which patients had used all their lives previously. There is the “reward” of being able to raise the arm as the individual intends, and the removal of the “positive punishment” of pain. If these results can be duplicated, the low cost, rapid acquisition and virtual absence of adverse effects will save a great deal of pain, time-of-healing, and health care funds. It requires no technical equipment, and as such would be applicable throughout the world. Shortcomings of the study: One major drawback to the study is the low long-term response rate in the follow-up. We believe the prolongation of the interval between seeing the participants and doing the follow-up due to the COVID-19 pandemic is one reason for this. Future studies can improve on this with more timely and more focused follow-up. Mandatory follow-up would improve the methodological design of future studies. The long follow-up was chiefly by telemedical means, which does not permit physical testing of strength or exact measurement of range of motion. These metrics would fill out the assessment of TFS in meaningful ways. Because it was a crossover study, there were no controls to match in the follow-up. The majority of studies that follow conservatively treated painful cuff tears that are monitored at regular intervals show tear enlargement and muscle degeneration over the years following tear detection 10-12 Another non-crossover study could compare the course of controls with the subsequent experience of those treated with TFS. Following these patients longer-term with further evaluation using Shoulder Pain and Disability Index (SPADI) and the American Shoulder and Elbow Surgeons (ASES) scores would contribute substantially to proving/disproving the value of the maneuver. Since recruitment of the subscapularis changes the kinetics of abduction and flexion, it is possible that arthritis of the joint will be accelerated by TFS. Longer term imaging follow-up with a larger sample would be desirable here too. Conclusion TFS may be an effective, inexpensive and immediately pain-relieving means of treating RCS. More study is desirable. Declarations Ethics Approval: Research reported in this publication was supported in part by the National Institute of Nursing Research of the National Institutes of Health under Awards Number R21NR016510, and conducted between April 20, 2021 and December 24, 2022, after a suspension due to the COVID-19 pandemic. The study was approved by the CIRBI IRB, now Advarra, and first submitted to Clinical Trials.gov, on April 6, 2021 and first posted on April 7, 202. It is listed as NCT04833244. Ethics approval and consent for participation and publication This study has been performed in accordance with the Declaration of Helsinki. Consent for publication Patients signed informed consent regarding participation, publishing their data and photographs. Competing interests The authors declare no competing interests. The data supporting this study can be found at Columbia University academic commons.edu. https://doi.org/10.7916/5xps-y460. Availability of Data: The demographic and study data used to support the findings of this study have been deposited in the Columbia University Academic repository: Academic [email protected] . https://doi.org/10.7916/5xps-y460 Competing Interests: The authors declare that they have no competing interests. Funding: Funding: National Institutes of Health under Awards Number R21NR016510. Authors’ Contributions: Dr. Fishman contributed to the paper’s conception, data acquisition, and interpretation and writing. Dr. Rosner contributed to the paper’s conception, study design, analysis, statistical analysis and interpretation. Acknowledgement: The authors acknowledge Eugenia Buta, Ph.D of Yale University for her assistance ithis paper. References Reilly P, Macleod I, Macfarlane R, Windley J, Emery RJ. Dead men and radiologists don't lie: a review of cadaveric and radiological studies of rotator cuff tear prevalence. Ann R Coll Surg Engl . 2006;88(2):116-121. doi:10.1308/003588406X94968 Yamamoto A, Takagishi K, Osawa T, et al. Prevalence and risk factors of a rotator cuff tear in the general population. J Shoulder Elbow Surg . 2010;19(1):116-120. doi:10.1016/j.jse.2009.04.006 Tashjian RZ. Epidemiology, natural history, and indications for treatment of rotator cuff tears. Clin Sports Med . 2012;31(4):589-604. doi:10.1016/j.csm.2012.07.001 Lenza M, Buchbinder R, Takwoingi Y, Johnston RV, Hanchard NC, Faloppa F. Magnetic resonance imaging, magnetic resonance arthrography and ultrasonography for assessing rotator cuff tears in people with shoulder pain for whom surgery is being considered. Cochrane Database Syst Rev . 2013;2013(9):CD009020. Published 2013 Sep 24. doi:10.1002/14651858.CD009020.pub2 Iannotti JP, Ciccone J, Buss DD, et al. Accuracy of office-based ultrasonography of the shoulder for the diagnosis of rotator cuff tears. J Bone Joint Surg Am . 2005;87(6):13051311. doi:10.2106/JBJS.D.02100 Teefey SA, Hasan SA, Middleton WD, Patel M, Wright RW, Yamaguchi K. Ultrasonography of the rotator cuff. A comparison of ultrasonographic and arthroscopic findings in one hundred consecutive cases. J Bone Joint Surg Am . 2000;82(4):498-50 Schemitsch C, Chahal J, Vicente M, et al. Surgical repair versus conservative treatment and subacromial decompression for the treatment of rotator cuff tears: a meta-analysis of randomized trials. Bone Joint J . 2019;101-B(9):1100-1106. doi:10.1302/0301620X.101B9.BJJ-2018-1591.R1 JeanfavreM,HustedS,LeffG. Exercise therapy in the non-operative treatment of full thickness rotator cuff tears: a systematic review. Int J Sports Phys Ther.2018 Jun; 13(3): 335–378.PMCID: PMC6044593. PMID:30038823 Hsu A, Choo A, Lee SK, et al. Clinical outcomes of conservative treatment and arthroscopic repair of rotator cuff tear in patients >50 years old at middle and advanced ages. Ann Rehabil Med . 2016;40(2):292-300. doi:10.5535/arm.2016.40.2.292. Kuhn JE. Exercise in the treatment of rotator cuff impingement and tears: a systematic review. J Shoulder Elbow Surg . 2009;18(1):138-150. doi:10.1016/j.jse.2008.06.002. Fleming JA, Seitz AL, Ebaugh DD. Exercise protocol for the treatment of rotator cuff impingement syndrome. J Athl Train . 2010;45(5):483-485. doi:10.4085/1062-6050-45.5.483 Longo UG, Carnevale A, Scaramuzzo L, et al. The conservative management of rotator cuff tears: a narrative review. J Clin Med . 2021;10(14):3134. doi:10.3390/jcm10143134. Rivas A, Soria R, Villalon G, et al. Long-term outcomes of physical therapy in patients with rotator cuff tears: a systematic review and meta-analysis. J Physiother . 222;68(1):28-36. doi:10.1016/j.jphys.2021.12.002. Fishman LM, Wilkins AN, Ovadia T, Konnoth C, Rosner B, Schmidhofer S. Yoga-Based Maneuver Effectively Treats Rotator Cuff Syndrome. Topics in Geriatric Rehabilitation:April/June 2011 - Volume 27 - Issue 2 - p 151-161.doi:10.1097/TGR.0b013e31821bfe68. Farrar JT, Young JP Jr, LaMoreaux L, Werth JL, Poole MR. Clinical importance of changes in chronic pain intensity measured on an 11-point numerical pain rating scale. Pain . 2001;94(2):149-158. doi:10.1016/S0304-3959(01)00349-9. Hsu J, Keener JD. Natural History of Rotator Cuff Disease and Implications on Management. Oper Tech Orthop . 2015;25(1):2-9. doi:10.1053/j.oto.2014.11.006. Keener JD, Galatz LM, Teefey SA, et al. A prospective evaluation of survivorship of asymptomatic degenerative rotator cuff tears. J Bone Joint Surg Am . 2015;97(2):89-98. doi:10.2106/JBJS.N.00099 Skinner, B. F. Two types of conditioned reflex and a pseudo type. Journal of General Psychology, 1935; 12 , 66-77. Additional Declarations No competing interests reported. Supplementary Files CONSORTFORRCSTFS4.20.24.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 11 Mar, 2026 Reviews received at journal 04 Feb, 2026 Reviewers agreed at journal 30 Jan, 2026 Reviews received at journal 15 Jan, 2026 Reviewers agreed at journal 13 Jan, 2026 Reviewers invited by journal 04 Nov, 2025 Editor assigned by journal 04 Nov, 2025 Editor invited by journal 03 Nov, 2025 Submission checks completed at journal 02 Nov, 2025 First submitted to journal 02 Nov, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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-7895251","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":542715236,"identity":"70acbc8e-542c-4682-b88c-e58095ccc387","order_by":0,"name":"Loren Fishman","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1ElEQVRIiWNgGAWjYBACPjBZwcDABqQOEKWFDUyeATGYSdHC2AYimYl0GBt778PHhfPq5PnYzx888KOGQc68fwEBLTzHjY1nbjts2MaTzHCw5xiDscyNBwS0SKSxSfNuO5DAxpDMcBjozsQZEgcIamH/zTunLoGN/zFQyz/itLAx8zYwJ7BJAG0BhkPiDP4GQn45xizNcwzoF4nHBgd7+ySMJSTw62DgZ29j/MxTUycv35/4+MOPbzZyEvwEHIYOgFZIJJCmBWQxibaMglEwCkbBsAcAenA4S2JFbasAAAAASUVORK5CYII=","orcid":"","institution":"Columbia University","correspondingAuthor":true,"prefix":"","firstName":"Loren","middleName":"","lastName":"Fishman","suffix":""},{"id":542715238,"identity":"fef6d4ee-3c3c-4bb1-85f9-ee7ef7f892b5","order_by":1,"name":"Bernard Rosner","email":"","orcid":"","institution":"Harvard University","correspondingAuthor":false,"prefix":"","firstName":"Bernard","middleName":"","lastName":"Rosner","suffix":""}],"badges":[],"createdAt":"2025-10-18 19:23:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7895251/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7895251/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":95917283,"identity":"96c29cba-d121-4c48-88ec-6afa28493211","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":3902713,"visible":true,"origin":"","legend":"","description":"","filename":"Edited11.2.25RCSMS.docx","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/2659e65d08d7c82625c3c284.docx"},{"id":95917277,"identity":"4d1acc56-c39e-4502-aa6b-f6e73aeea23a","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"json","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":3236,"visible":true,"origin":"","legend":"","description":"","filename":"4c8948d40ef84885aa8d2b4f806e527f.json","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/97a4937ea4f380348caf5106.json"},{"id":96243179,"identity":"9fd9772e-8b1d-4785-882a-48daad8209ad","added_by":"auto","created_at":"2025-11-19 07:15:48","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":73675,"visible":true,"origin":"","legend":"","description":"","filename":"CONSORTFORRCSTFS4.20.24.docx","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/d509b6e8560a008d53f0e72d.docx"},{"id":96243286,"identity":"bb3e5117-feb2-447c-a1f6-457893ac6b3f","added_by":"auto","created_at":"2025-11-19 07:15:59","extension":"xml","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":106056,"visible":true,"origin":"","legend":"","description":"","filename":"4c8948d40ef84885aa8d2b4f806e527f1enriched.xml","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/f7c3e8e77523084f5d2de4e9.xml"},{"id":96242900,"identity":"6652c3ea-4980-436c-99c1-9872723aeff9","added_by":"auto","created_at":"2025-11-19 07:14:50","extension":"eps","order_by":5,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":572,"visible":true,"origin":"","legend":"","description":"","filename":"drawingimage2.eps","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/f598a53cb6b4b545216d46b6.eps"},{"id":95917286,"identity":"41cdf02e-6bc3-4ce6-9a3d-cd8342c6601f","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"png","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":310281,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/1736b035aad47a64919d91e8.png"},{"id":96243621,"identity":"78887639-efee-4da6-9fc7-0a412734fd62","added_by":"auto","created_at":"2025-11-19 07:16:45","extension":"png","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":142331,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/a126cfc1b888c063e90eb581.png"},{"id":96243531,"identity":"6296807a-e9c2-41ac-8824-27980abce18d","added_by":"auto","created_at":"2025-11-19 07:16:37","extension":"jpeg","order_by":8,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1015280,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/c61f30e6bbb30174c57477b3.jpeg"},{"id":95917289,"identity":"be19ad1d-bcc7-4316-8a4c-5f9818f18ebe","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"jpeg","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1074,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/d6d783c5fdd00b6198cc2b09.jpeg"},{"id":95917296,"identity":"2dcdc17b-fd24-4f62-8d2e-56a2a0288437","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"png","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":592286,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/d3aab4aa2a87abe921982269.png"},{"id":95917294,"identity":"0ae05a24-aa7c-4302-bc17-d4c703c838a6","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"png","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":837992,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/5b3ed48ac236a041c696bbb4.png"},{"id":96243538,"identity":"aa096dfc-b023-4c14-9fcc-cfc6c30c5928","added_by":"auto","created_at":"2025-11-19 07:16:38","extension":"png","order_by":12,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":24976,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/39205e206395b2767ec89320.png"},{"id":95917295,"identity":"cc05ff3b-51d0-4512-af13-10c4b7a4d0c4","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"png","order_by":13,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":42333,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/884b32b70aa7cabbec29f9ed.png"},{"id":95917300,"identity":"a55ca40d-47e6-4bc8-b440-0bcc1337a9c3","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"png","order_by":14,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":194436,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/2509fe83385448b585af7c35.png"},{"id":96243232,"identity":"6bb44bf9-f219-4fba-b22a-dedb115ae52a","added_by":"auto","created_at":"2025-11-19 07:15:53","extension":"png","order_by":15,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":935,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/cc6ffff4bf7ed274f947cacc.png"},{"id":96244049,"identity":"e162c657-5918-4347-9b61-db207ca71b0c","added_by":"auto","created_at":"2025-11-19 07:17:39","extension":"png","order_by":16,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":46349,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/eb3a745c05e8773d53414bd5.png"},{"id":95917299,"identity":"f005e633-7da4-4329-b25d-a443cbe7e810","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"png","order_by":17,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":74883,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/b4abafd4d21d79a572d769b9.png"},{"id":95917291,"identity":"2d2fbfe7-ee99-4c91-9cfe-11991eb04483","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"xml","order_by":18,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":102969,"visible":true,"origin":"","legend":"","description":"","filename":"4c8948d40ef84885aa8d2b4f806e527f1structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/eca6e10c2b1bc7b9831286ca.xml"},{"id":95917298,"identity":"afdd9c2e-c99c-4d75-b8e1-21741da3815f","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"html","order_by":19,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":117717,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/acf761b0ec56ccb6012f2290.html"},{"id":96243860,"identity":"51adb088-0808-4506-80ed-6802fa14a4b5","added_by":"auto","created_at":"2025-11-19 07:17:11","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":98085,"visible":true,"origin":"","legend":"\u003cp\u003eSlight gravitational pull is a foil for the activated subscapularis.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/29645afc9e9206baffa5765c.png"},{"id":95917275,"identity":"abfad42e-b06a-4ed5-9b14-5c12ced35a08","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":63576,"visible":true,"origin":"","legend":"\u003cp\u003eFlow chart.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/772231eccf02cc219a3c8bdb.png"},{"id":96245129,"identity":"8b8fc52c-0b49-4e75-8ca1-73354b5b5e73","added_by":"auto","created_at":"2025-11-19 07:19:54","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":409349,"visible":true,"origin":"","legend":"\u003cp\u003eMassive supraspinatus tear after TFS: Comparison of shoulder kinetics after surgery vs. following triangular forearm support. After TFS subscapularis cantilevers the humerus from 80 -110 degrees as indicated by the spindle of activity in that range, while the deltoid reduces its pull to act as a fulcrum supporting the proximal humerus from above.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/869b2fd674c7f504ea9ee807.png"},{"id":96243986,"identity":"885dc7d4-b215-4cb4-a205-94a6bebb9e3b","added_by":"auto","created_at":"2025-11-19 07:17:28","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":109288,"visible":true,"origin":"","legend":"\u003cp\u003eThe TFS activates the subscapularis and inhibits the deltoid, so the arm is now lifted by virtue of a cantilever.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/4962a1b10c51e9c0da9e6d73.png"},{"id":95917278,"identity":"eb264dc1-4c6c-414e-b96f-c376b2d3c577","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":21922,"visible":true,"origin":"","legend":"\u003cp\u003eReduction in pain over mean 52 months following triangular forearm support.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/20aae4b95a679b1a7b5fc3be.png"},{"id":95917280,"identity":"6b4fa0c7-c118-4130-b1da-6f2357d87c60","added_by":"auto","created_at":"2025-11-14 12:07:56","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":273713,"visible":true,"origin":"","legend":"\u003cp\u003ePainless range of motion improvement after 30 months in an earlier study of\u003c/p\u003e\n\u003cp\u003eTFS.\u003csup\u003e12\u003c/sup\u003e Note shoulder on curve at 125-150% improvement.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/c7b5034cff36f503935b2800.png"},{"id":96255307,"identity":"8627ddd0-17c5-47d2-87e8-aade0cd932eb","added_by":"auto","created_at":"2025-11-19 07:48:23","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1145740,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/1b9ec577-33a1-4a51-a89a-687326329222.pdf"},{"id":96243589,"identity":"24fb72e3-6aa4-4d78-9efd-88f57e63b9cf","added_by":"auto","created_at":"2025-11-19 07:16:41","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":73675,"visible":true,"origin":"","legend":"","description":"","filename":"CONSORTFORRCSTFS4.20.24.docx","url":"https://assets-eu.researchsquare.com/files/rs-7895251/v1/c05892bff01f02fa273f5bdc.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Triangular Forearm Support in Rotator Cuff Syndrome a randomized crossover trial with EMG insight into mechanism of action","fulltext":[{"header":"What is already known","content":"\u003cp\u003eA protracted course of conservative therapy can rehabilitate people with partial tear rotator cuff syndrome (RCS) non-inferiorly to surgical intervention, but conservative therapy is inferior to surgical intervention in full thickness tears.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat this study adds:\u003c/strong\u003e Triangular forearm support is a conservative method that reduces RCS pain in 2.5-year follow-up with kinesiological alterations independent of the severity of the tear.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;How might this affect clinical thought and practice?\u0026nbsp;\u003c/strong\u003eIn the clinic, a practical and innocuous treatment of RCS has immediate benefits for the patients, the clinicians and the health care system. In research, an example of beneficially altered shoulder kinetics might inspire other research toward similar beneficial alterations. Successful use of this maneuver might effect changes in emphasis for research funding policy and the best practices policy for clinical interventions.\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eRotator cuff syndrome is one of the most common orthopedic injuries of the upper extremities, with biphasic incidence peaks at 35 and 55 years of age.\u003csup\u003e1-3\u003c/sup\u003e Cadaveric studies find nearly 50% of individuals over 80 years of age have significant rotator cuff tears.\u003csup\u003e1,2\u003c/sup\u003e Although ultrasound is often diagnostic, MRI is still the most reliable means of making the diagnosis.\u003csup\u003e4-6\u003c/sup\u003e \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSurgery has been more successful with chronic and acute tears than conservative therapy\u003csup\u003e7\u0026nbsp;\u003c/sup\u003eas currently administered. \u0026nbsp;More than 10% of conservatively treated RCS patients progress to surgery\u003csup\u003e8,9\u0026nbsp;\u003c/sup\u003eand then to physical therapy, although conservative means are not inferior to arthroscopic interventions\u003csup\u003e7\u003c/sup\u003e with respect to pain in smaller tears. \u0026nbsp;Recovery of strength after conservative methods is debatable,\u003csup\u003e8,9\u003c/sup\u003e but generally found inferior to post-surgical recovery.\u003csup\u003e10,11\u0026nbsp;\u003c/sup\u003eFull recovery after surgery takes seven to ten months and is painful and costly. \u0026nbsp; A more effective conservative treatment would be welcome.\u003c/p\u003e\n\u003cp\u003eOur objective was to determine if an isometric yoga-like maneuver could relieve the symptoms of RCS in the long term, and to examine the shoulder kinetics it utilizes.\u003c/p\u003e\n\u003cp\u003eThe supraspinatus muscle is torn in 90% of RCS,\u003csup\u003e3\u003c/sup\u003e rendering abduction and flexion to 90 degrees very painful or frankly impossible. At this angle the deltoid\u0026rsquo;s fibers are pulling horizontally, without a vertical component; abduction and flexion within the 80 \u0026ndash; 110-degree range therefore depend on the supraspinatus and to a lesser extent, the infraspinatus. When the supraspinatus is torn or divided, abduction and flexion become problematical: these motions are painful in the case of a tear and seemingly impossible if the supraspinatus is transected. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFigure 1:\u003c/p\u003e\n\u003cp\u003eWe serendipitously found a yoga maneuver, the triangular forearm support (TFS) that seemed to accomplish this task and tested it in a non-randomized study.\u003csup\u003e12\u0026nbsp;\u003c/sup\u003eSee figure 1. This paper reports a randomized controlled test of its utility and secondarily probes both the mechanism by which it may succeed, and the longevity of the improvement.\u0026nbsp;\u003c/p\u003e"},{"header":"Methods","content":"\u003cul\u003e\n \u003cli\u003eThe study took place in private offices in Manhattan.Research reported in this publication was supported in part by the National Institute of Nursing Research of the National Institutes of Health under Awards Number R21NR016510, and conducted between April 6, 2021 and December 24, 2022, after a suspension due to the COVID-19 pandemic. The study was approved by the CIRBI IRB, now Advarra, and first submitted to Clinical Trials.gov, on April 6, 2021 and first posted on April 7, 2021. It is listed as\u0026nbsp;NCT04833244.\u0026nbsp;\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eInclusion criteria:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMRI confirmation of partial or full-thickness tear of the supraspinatus muscle or its tendon.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSelf-rated pain in abduction or flexion equal to or above 5/10 on the visual analogue scale (VAS).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eExclusion criteria:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp; \u0026nbsp;\u0026nbsp;\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Previous ipsilateral shoulder surgery.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNeuromuscular conditions such as amyotrophic lateral sclerosis, cerebrovascular accident, or cerebral palsy affecting the ipsilateral shoulder.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSelf-rated pain in abduction and flexion below 5/10 on the VAS.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAfter signing the Informed Consent forms, selected patients were randomized using random.com. Participants were blinded to their assignment into intervention (IG) or control groups (CG). Bilateral abduction and flexion with straight elbows were performed by both IG and CG three times (three maximal shoulder abductions followed by three maximal shoulder flexions) both before and after the TFS maneuver was taught. See figure 1. The examiner displayed each movement before the subject was asked to do it. Immediately following each abduction and each flexion, the subject stated his or her assessment of the most intense pain felt during that action on a 0-10 VAS scale. The examiner recorded these values. \u0026nbsp;Full silence was maintained, apart from the verbal report of maximal pain felt by the subject. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAfter three abductions and flexions, the IG patients were taught TFS, and the CG patients were taught a sham procedure. \u0026nbsp; The abductions and flexions were then repeated for all patients with the same pain-scale rating procedure as before. At this point the intervention-group patients were finished with the study, except for the years-later follow-up. \u0026nbsp;The sham-group patients were taught TFS immediately after the second rating, followed by a third series of flexion and abduction with VAS rating. See figure 2.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFigure 2:\u003c/p\u003e\n\u003cp\u003eFollow-up was sought in up to three emails and three phone calls. Due to the COVID pandemic follow-up times were significantly increased. Mean follow-up time was 52 months; range 29 \u0026ndash; 60 months. Participants were asked to rate their pain with abduction and flexion, along with any relevant mishaps or treatment or relevant medications they encountered in the interim.\u003c/p\u003e\n\u003cp\u003eDetails of the procedure: \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe TFS maneuver consists of folding one\u0026rsquo;s hands with palms together and placing the forearms against a wall with head in the center of the triangle made by the forearms, then pulling the shoulders away from the wall until the superior third of the trapezius and the supraspinatus become soft. For an example of the TFS maneuver, readers are referred to the video on You Tube: https://www.youtube.com/watch?v=jzOsaE0Kyq8\u003c/p\u003e\n\u003cp\u003eActivation of the subscapularis was gauged by means of the agonist-antagonist reflex: \u0026nbsp;We worked with the patient until the supraspinatus and superior 1/3 of the trapezius were relaxed, indicating that the subscapularis was active. \u0026nbsp;We did this by palpating these muscles just rostral to the scapular spine.\u003c/p\u003e\n\u003cp\u003eControl group participants were asked to interdigitate their hands in front of themselves with elbows straight and hold the position for 45 seconds.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eImmediately after performing the TFS maneuver or placebo maneuver for 45 seconds, patients were encouraged to \u0026ldquo;bravely, boldly, fearlessly\u0026rdquo; maximally abduct their arms three times and then flex their shoulders three times with elbows straight. \u0026nbsp;These maneuvers were verbally rated on the VAS reflecting the maximum pain felt with each abduction and each flexion. \u0026nbsp;The examiner recorded the participants\u0026rsquo; maximal pain responses to the abductions and flexions on a score sheet.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe demographic and study data used to support the findings of this study have been deposited in the Columbia University Academic repository: Academic [email protected]. https://doi.org/10.7916/5xps-y460\u003c/p\u003e\n\u003cp\u003eStatistical approach:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe three pre-maneuver (or placebo) abduction and three pre-intervention (or placebo) flexion scores given by the subjects were averaged separately, and differences between the pre- and post-maneuver or post-placebo scores were sought. The power calculations for this paper involved alpha of .05 and power of 80%, and the assumption that the placebo group would differ from the intervention group by 25%. This assumption was based on an earlier paper studying the maneuver.\u003csup\u003e12\u003c/sup\u003e This study used t-tests and Wilcoxon rank sum tests. \u0026nbsp;These tests were paired or unpaired as appropriate. We also used paired t-tests to compare abduction and flexion pain scores post-intervention with abduction and flexion pain at follow-up using the survey questions \u0026ldquo;On a scale of 0-10, how much pain do you feel now lifting that arm to the \u003cem\u003eside\u003c/em\u003e?\u0026quot;, and \u0026quot;On a scale of 0-10, much pain do you feel now lifting that arm out \u003cem\u003ein front\u003c/em\u003e of you?\u0026quot; respectively. We averaged pain across the two arms for subjects who had RCS in both shoulders.\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e212 patients were recruited, of which 167 completed the procedure properly. \u0026nbsp;There were 80 intervention and 87 control-plus-crossover patients with mean age of 64.52 years. See table 1. No patients were lost to the immediate follow-up since the single assessment immediately followed the intervention and placebo maneuvers. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMean intervention patients\u0026rsquo; pain scores for abduction and flexion were immediately reduced from 6.14 and 5.13, respectively by 1.98 and 1.64 points (CI: .0526; .0438) respectively, a reduction of 32.3% and 32.0 %. \u0026nbsp; In contrast, mean sham patients\u0026rsquo; pain scores for abduction and flexion were reduced from 5.03 and 4.57 by 1.08 and .93 points, (CI: .0513; .0357), 21.5% and 21.4%, respectively. \u0026nbsp;T-test values for patients\u0026rsquo; pain scores for abduction and flexion were p \u0026lt; .002 and p \u0026lt; .008 respectively, and Wilcoxon rank sum test values were p \u0026lt; .004 and p \u0026lt; .002 respectively in IG vs. CG. \u0026nbsp; When the CG patients were given TFS immediately thereafter, their mean VAS scores were reduced by 1.25 and 1.39 for abduction and flexion (CI: \u0026plusmn;.378; \u0026plusmn;.340) or 24.9% and 28.2% respectively. See table 2.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWe also recorded whether the tears were full thickness or partial thickness, and whether they were in dominant or non-dominant arm. The effect of TFS was not significantly different when grouped by nature of the tear of the supraspinatus or infraspinatus. \u0026nbsp;See table 3. \u0026nbsp;Also, the differences in outcomes where the dominant vs. non-dominant upper extremity was affected were insignificant.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe 3-year clinical effort abruptly came to an end on March 13, 2020 with the COVID-19 pandemic being declared a national emergency. \u0026nbsp;Seventy-three patients responded to the mean 52 months\u0026rsquo; post-intervention inquiries. Mean 52 months\u0026rsquo; follow-up found that 3 patients had required surgery, 3 had platelet rich plasma injections and 13 of the 73 responding patients received further physical therapy. Since the CG patients were shown the TFS maneuver immediately after their post-placebo testing, there were no controls for the long-range follow-up. However, we sought changes in the combined IG + CG patients for long-term follow-up, since at that point all subjects had had the TFS maneuver. Of the 54 patients without confounding events or further treatment, abduction VAS scores for flexion and abduction were 1.53 and 1.04 (SD 2.50; 2.25) respectively as compared with study-start values of 6.14 and 5.13, giving improvement of 75.6% and 75.6% respectively. \u0026nbsp;See table 4.\u003c/p\u003e\n\u003cp\u003eThe 54 unconfounded subjects\u0026rsquo; abduction pain decreased from a mean of 2.45 (SD=2.34) post-intervention to 1.53 (SD=2.28) at follow-up a mean improvement of 0.92 points (95% CI 0.13 to 1.71), p=0.02). These patients\u0026rsquo; flexion pain decreased from a mean of 2.17 (SD=2.26) post-intervention to 1.04 (1.79) at follow-up, a mean improvement of 1.13 points (95% CI 0.54 to 1.73), p\u0026lt;0.001). See table 5 and figure 3.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAdverse effects: One patient who did not improve complained of significant pain following TFS. She refused MRI or other follow-up. \u0026nbsp; Apart from this no adverse side effects from the procedure were noted.\u003c/p\u003e\n\u003cp\u003eBetter to understand how the TFS initiated this rapid change in function, and relate the anatomy and kinesiology to clinical reality, we studied the TFS maneuver with 8 channel EMG. Monopolar 37 mm needle electrodes and reference electrodes were placed in the supraspinatus, infraspinatus, deltoid, rhomboid major, pectoralis, serratus anterior, teres minor and latissimus dorsi muscles, with ground on the sternum, using a Sierra Wave II electrodiagnostic device set at 100 microvolts and 10 ms per division. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOne subject abducted repeatedly in this montage. \u0026nbsp;The subject had had RCS surgery for a partial tear in his right shoulder ten years earlier, and an untreated massive tear on the left in which the supraspinatus muscle was wholly divided into two fragments.2.5 cm apart. This shoulder was treated with TFS. In the post-surgical EMG the right supraspinatus began acting at 80 degrees, as the deltoid\u0026rsquo;s fibres approached horizontal. This is what normally happens in people\u0026rsquo; shoulders that do not have RCS. But post TFS, the left supraspinatus showed early activity that did not change at 80 degrees; it was not the abducting force here. In the TFS arm a spindle of subscapularis activity begins at 80 degrees and is evidence that the subscapularis took up the abduction function previously assumed by the supraspinatus at 80 degrees. \u0026nbsp;The amplitude of the TFS side\u0026rsquo;s deltoid activity \u003cem\u003edecreased\u003c/em\u003e in the range of 80 \u0026ndash; 110 degrees, suggesting that it functioned to stabilize the proximal humeral shaft, acting from above the humerus as a fulcrum as the subscapularis\u0026rsquo; contraction cantilevered the distal shaft of the humerus upward. \u0026nbsp;The subscapularis, with its attachment closer to the humeral head, pulled the humeral head downward, which cantilevered its more distal shaft upward. See figures 1, 3, 4.\u003c/p\u003e\n\u003cp\u003eFigure 3:\u003c/p\u003e\n\u003cp\u003eThe rhomboides and pectoralis muscles were activated in tandem in both the surgical and TFS arms: \u0026nbsp;both dorsal and ventral pressures from these muscles have an inferior pointed vector that can sum to stabilize the scapula and aid the work of the functioning right subscapularis, with which they were simultaneously activated.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSummary of kinetics of abduction/flexion after TFS\u003c/p\u003e\n\u003cp\u003eWhile the subscapularis cantilevers the humerus from 80 -110 degrees; the supraspinatus, in this case massively torn, had no part in the action, with just mild continuous activity throughout abduction. The subscapularis\u0026rsquo; EMG record denotes heightened activity exactly between 80 and 110 degrees, where the deltoid\u0026rsquo;s effect on abduction and flexion is virtually null.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThis principle was supported by the lack of relationship between the severity of the tear (more than 50% vs. less than 50%) and the degree of improvement in pain. The efficacy of TFS with full as well as partial tears suggests that the maneuver does not particularly depend on strength, but rather replacing a torn muscle\u0026rsquo;s function with another muscle used in a different way, but with similar results. \u0026nbsp;See table 3.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe improvement with TFS is significant in the academic sense but is it clinically significant.? Farrar, et. al.\u003csup\u003e13\u003c/sup\u003e point out that gaining points on a Likert-type scale may have very different clinical impact but state that a reduction of 2 points or 30% is generally clinically significant. \u0026nbsp;To this end we have included the initial scores, which lie in the middle range: 5 – 6/10. \u0026nbsp;See table 2. People’s pain levels improved 75.6% over the years between study entry and follow-up. \u0026nbsp;See table 4 and figure 4.\u003c/p\u003e\n\u003cp\u003eFigure 5:\u003c/p\u003e\n\u003cp\u003eThe more than ¾ overall mean improvement over the follow-up period might be attributable to slow healing that would occur naturally over four years. \u0026nbsp; However, the natural history of untreated RCS is that it worsens over time.\u003csup\u003e14,15\u003c/sup\u003e Therefore it is likely that TFS is a significant factor in patients’ improvement.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eStrategic use of TFS\u003c/p\u003e\n\u003cp\u003eThe clinical significance of this maneuver, however, depends on its longevity. A previous study followed 50 patients for 30 months and found that 94% of the patients doubled their flexion and abduction ranges and reduced their pain more than 80% throughout that time span.\u003csup\u003e12\u003c/sup\u003e In that study most patients repeated the TFS maneuver daily for a few weeks, but then the shoulder stayed painlessly high functioning without further intervention for the 30 months for which they were studied. \u0026nbsp;In this study we used telephone, email and Zoom to communicate with patients years after the initial intervention. See figure 5.\u003c/p\u003e\n\u003cp\u003eFigure 6\u003c/p\u003e\n\u003cp\u003eThe long-lasting effect of TFS may be a case of muscle re-learning, or operant conditioning,\u003csup\u003e16\u003c/sup\u003e a non-conscious adaptation in which patients spontaneously choose the painless cantilevering action of the subscapularis for abducting and flexing the shoulder over the otherwise ineffective and painful use of the torn supraspinatus which patients had used all their lives previously. There is the “reward” of being able to raise the arm as the individual intends, and the removal of the “positive punishment” of pain.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;If these results can be duplicated, the low cost, rapid acquisition and virtual absence of adverse effects will save a great deal of pain, time-of-healing, and health care funds. \u0026nbsp;It requires no technical equipment, and as such would be applicable throughout the world.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eShortcomings of the study:\u003c/p\u003e\n\u003cp\u003eOne major drawback to the study is the low long-term response rate in the follow-up. We believe the prolongation of the interval between seeing the participants and doing the follow-up due to the COVID-19 pandemic is one reason for this. \u0026nbsp;Future studies can improve on this with more timely and more focused follow-up. Mandatory follow-up would improve the methodological design of future studies.\u003c/p\u003e\n\u003cp\u003eThe long follow-up was chiefly by telemedical means, which does not permit physical testing of strength or exact measurement of range of motion. \u0026nbsp;These metrics would fill out the assessment of TFS in meaningful ways.\u003c/p\u003e\n\u003cp\u003eBecause it was a crossover study, there were no controls to match in the follow-up. The majority of studies that follow conservatively treated painful cuff tears that are monitored at regular intervals show tear enlargement and muscle degeneration over the years following tear detection\u003csup\u003e10-12\u0026nbsp;\u003c/sup\u003eAnother non-crossover study could compare the course of controls with the subsequent experience of those treated with TFS.\u003c/p\u003e\n\u003cp\u003eFollowing these patients longer-term with further evaluation using Shoulder Pain and Disability Index (SPADI) and the American Shoulder and Elbow Surgeons (ASES) scores would contribute substantially to proving/disproving the value of the maneuver.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSince recruitment of the subscapularis changes the kinetics of abduction and flexion, it is possible that arthritis of the joint will be accelerated by TFS. \u0026nbsp;Longer term imaging follow-up with a larger sample would be desirable here too.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eTFS may be an effective, inexpensive and immediately pain-relieving means of treating RCS. More study is desirable.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cul\u003e\n \u003cli\u003eEthics Approval:\u003c/li\u003e\n \u003cli\u003eResearch reported in this publication was supported in part by the National Institute of Nursing Research of the National Institutes of Health under Awards Number R21NR016510, and conducted between April 20, 2021 and December 24, 2022, after a suspension due to the COVID-19 pandemic. The study was approved by the CIRBI IRB, now Advarra, and first submitted to Clinical Trials.gov, on April 6, 2021 and first posted on April 7, 202. It is listed as NCT04833244.\u0026nbsp;\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eEthics approval and consent for participation and publication\u003c/p\u003e\n\u003cp\u003eThis study has been performed in accordance with the Declaration of Helsinki.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eConsent for publication\u003c/p\u003e\n\u003cp\u003ePatients signed informed consent regarding participation, publishing their data and photographs.\u003c/p\u003e\n\u003cp\u003eCompeting interests\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003eThe data supporting this study can be found at Columbia University academic commons.edu. https://doi.org/10.7916/5xps-y460.\u003c/p\u003e\n\u003cp\u003eAvailability of Data:\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;The demographic and study data used to support the findings of this study have been deposited in the Columbia University Academic repository: Academic [email protected]. https://doi.org/10.7916/5xps-y460\u003c/p\u003e\n\u003cp\u003eCompeting Interests:\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003eFunding:\u003c/p\u003e\n\u003cp\u003eFunding: National Institutes of Health under Awards Number R21NR016510.\u003c/p\u003e\n\u003cp\u003eAuthors’ Contributions:\u003c/p\u003e\n\u003cp\u003eDr. Fishman contributed to the paper’s conception, data acquisition, and interpretation and writing.\u003c/p\u003e\n\u003cp\u003eDr. Rosner contributed to the paper’s conception, study design, analysis, statistical analysis and interpretation.\u003c/p\u003e\n\u003cp\u003eAcknowledgement:\u003c/p\u003e\n\u003cp\u003eThe authors acknowledge Eugenia Buta, Ph.D of Yale University for her assistance ithis paper.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eReilly P, Macleod I, Macfarlane R, Windley J, Emery RJ. Dead men and radiologists don\u0026apos;t lie: a review of cadaveric and radiological studies of rotator cuff tear prevalence. \u003cem\u003eAnn R Coll Surg Engl\u003c/em\u003e. 2006;88(2):116-121. doi:10.1308/003588406X94968\u003c/li\u003e\n \u003cli\u003eYamamoto A, Takagishi K, Osawa T, et al. Prevalence and risk factors of a rotator cuff tear in the general population. \u003cem\u003eJ Shoulder Elbow Surg\u003c/em\u003e. 2010;19(1):116-120. doi:10.1016/j.jse.2009.04.006\u003c/li\u003e\n \u003cli\u003eTashjian RZ. Epidemiology, natural history, and indications for treatment of rotator cuff tears. \u003cem\u003eClin Sports Med\u003c/em\u003e. 2012;31(4):589-604. doi:10.1016/j.csm.2012.07.001\u003c/li\u003e\n \u003cli\u003eLenza M, Buchbinder R, Takwoingi Y, Johnston RV, Hanchard NC, Faloppa F. Magnetic resonance imaging, magnetic resonance arthrography and ultrasonography for assessing rotator cuff tears in people with shoulder pain for whom surgery is being considered. \u003cem\u003eCochrane Database Syst Rev\u003c/em\u003e. 2013;2013(9):CD009020. Published 2013 Sep 24. doi:10.1002/14651858.CD009020.pub2\u003c/li\u003e\n \u003cli\u003eIannotti JP, Ciccone J, Buss DD, et al. Accuracy of office-based ultrasonography of the shoulder for the diagnosis of rotator cuff tears. \u003cem\u003eJ Bone Joint Surg Am\u003c/em\u003e. 2005;87(6):13051311. doi:10.2106/JBJS.D.02100\u003c/li\u003e\n \u003cli\u003eTeefey SA, Hasan SA, Middleton WD, Patel M, Wright RW, Yamaguchi K. Ultrasonography of the rotator cuff. A comparison of ultrasonographic and arthroscopic findings in one hundred consecutive cases. \u003cem\u003eJ Bone Joint Surg Am\u003c/em\u003e. 2000;82(4):498-50\u003c/li\u003e\n \u003cli\u003eSchemitsch C, Chahal J, Vicente M, et al. Surgical repair \u003cem\u003eversus\u003c/em\u003e conservative treatment and subacromial decompression for the treatment of rotator cuff tears: a meta-analysis of randomized trials. \u003cem\u003eBone Joint J\u003c/em\u003e. 2019;101-B(9):1100-1106. doi:10.1302/0301620X.101B9.BJJ-2018-1591.R1\u003c/li\u003e\n \u003cli\u003eJeanfavreM,HustedS,LeffG. Exercise therapy in the non-operative treatment of full thickness rotator cuff tears: a systematic review. Int J Sports Phys Ther.2018 Jun; 13(3): 335\u0026ndash;378.PMCID: PMC6044593. PMID:30038823\u003c/li\u003e\n \u003cli\u003eHsu A, Choo A, Lee SK, et al. Clinical outcomes of conservative treatment and arthroscopic repair of rotator cuff tear in patients \u0026gt;50 years old at middle and advanced ages. \u003cem\u003eAnn Rehabil Med\u003c/em\u003e. 2016;40(2):292-300. doi:10.5535/arm.2016.40.2.292.\u003c/li\u003e\n \u003cli\u003eKuhn JE. Exercise in the treatment of rotator cuff impingement and tears: a systematic review. \u003cem\u003eJ Shoulder Elbow Surg\u003c/em\u003e. 2009;18(1):138-150. doi:10.1016/j.jse.2008.06.002.\u003c/li\u003e\n \u003cli\u003eFleming JA, Seitz AL, Ebaugh DD. Exercise protocol for the treatment of rotator cuff impingement syndrome. \u003cem\u003eJ Athl Train\u003c/em\u003e. 2010;45(5):483-485. doi:10.4085/1062-6050-45.5.483\u003c/li\u003e\n \u003cli\u003eLongo UG, Carnevale A, Scaramuzzo L, et al. The conservative management of rotator cuff tears: a narrative review. \u003cem\u003eJ Clin Med\u003c/em\u003e. 2021;10(14):3134. doi:10.3390/jcm10143134.\u003c/li\u003e\n \u003cli\u003eRivas A, Soria R, Villalon G, et al. Long-term outcomes of physical therapy in patients with rotator cuff tears: a systematic review and meta-analysis. \u003cem\u003eJ Physiother\u003c/em\u003e. 222;68(1):28-36. doi:10.1016/j.jphys.2021.12.002.\u003c/li\u003e\n \u003cli\u003eFishman LM, Wilkins AN, Ovadia T, Konnoth C, Rosner B, Schmidhofer S. Yoga-Based Maneuver Effectively Treats Rotator Cuff Syndrome. Topics in Geriatric Rehabilitation:April/June 2011 - Volume 27 - Issue 2 - p 151-161.doi:10.1097/TGR.0b013e31821bfe68.\u003c/li\u003e\n \u003cli\u003eFarrar JT, Young JP Jr, LaMoreaux L, Werth JL, Poole MR. Clinical importance of changes in chronic pain intensity measured on an 11-point numerical pain rating scale. \u003cem\u003ePain\u003c/em\u003e. 2001;94(2):149-158. doi:10.1016/S0304-3959(01)00349-9.\u003c/li\u003e\n \u003cli\u003eHsu J, Keener JD. Natural History of Rotator Cuff Disease and Implications on Management. \u003cem\u003eOper Tech Orthop\u003c/em\u003e. 2015;25(1):2-9. doi:10.1053/j.oto.2014.11.006.\u003c/li\u003e\n \u003cli\u003eKeener JD, Galatz LM, Teefey SA, et al. A prospective evaluation of survivorship of asymptomatic degenerative rotator cuff tears. \u003cem\u003eJ Bone Joint Surg Am\u003c/em\u003e. 2015;97(2):89-98. doi:10.2106/JBJS.N.00099\u003c/li\u003e\n \u003cli\u003eSkinner, B. F. Two types of conditioned reflex and a pseudo type. \u003cem\u003eJournal of General Psychology,\u0026nbsp;\u003c/em\u003e1935; \u003cem\u003e12\u003c/em\u003e, 66-77.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"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":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Rotator cuff syndrome, Triangular forearm support, Kinesiology, Yoga, Cantilever, EMG ","lastPublishedDoi":"10.21203/rs.3.rs-7895251/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7895251/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eDesign: Randomized blinded control crossover of yoga-like maneuver treating MRI confirmed rotator cuff syndrome (RCS); minimum 29-month follow-up.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePatient selection\u003c/em\u003e: RCS pain \u0026gt;5/10 on visual analogue scale (VAS). Intervention (80) and placebo (87) groups.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eIntervention\u003c/em\u003e: Triangular forearm support (TFS).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eMain outcome measures\u003c/em\u003e: VAS, shoulder kinetics.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eMethods\u003c/em\u003e: Patient-rated abduction and flexion pain pre – and post – TFS, and multi-channel EMG.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eResults\u003c/em\u003e: Intervention group: Abduction: mean post-TFS and post-placebo VAS dropped 1.98 and 1.08 points from 6.14 and 5.03 respectively or 32.3% vs. 21%, respectively. Flexion: baseline intervention group values: 5.13 and 4.57 dropped 1.08 and .93 points, 32% and 20.4% lower, respectively. (p =.002; p \u0026lt;.008). Placebo group’s crossover post TFS: mean abduction and flexion VAS dropped 1.25 and 1.39 respectively. All tests: p \u0026lt; .001. Mean 52-month follow-up for all patients: abduction and flexion VAS: mean improvement from initial post-TFS VAS: 0.92 points (95% CI: 0.13 to 1.71), p = 0.02 and 1.13 points (95% CI 0.54 - 1.73), p \u0026lt;0.001) respectively. VAS values for abduction and flexion were 67.6% and 74.5% below baseline.\u003c/p\u003e\n\u003cp\u003ePost-TFS EMG of abduction showed greater activation of the subscapularis, less in deltoid, suggesting cantilevering the humerus upward between 80 – 110 degrees.\u003c/p\u003e\n\u003cp\u003eConclusion: The TFS maneuver may be helpful in RCS by employing a cantilever mechanism in abduction and flexion.\u003c/p\u003e","manuscriptTitle":"Triangular Forearm Support in Rotator Cuff Syndrome a randomized crossover trial with EMG insight into mechanism of action","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-14 12:07:51","doi":"10.21203/rs.3.rs-7895251/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-11T13:35:32+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-04T11:44:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"9131386652041760230848871598429716633","date":"2026-01-30T23:06:03+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-15T12:52:13+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"112758522101576862336962817819935719206","date":"2026-01-13T08:04:22+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-11-04T21:20:55+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-11-04T21:19:57+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-11-03T06:03:22+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-11-02T15:41:26+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Musculoskeletal Disorders","date":"2025-11-02T14:53:13+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"21b73e4b-e413-47a9-9291-4c0ebacbff1c","owner":[],"postedDate":"November 14th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-03-26T14:23:32+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-14 12:07:51","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7895251","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7895251","identity":"rs-7895251","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}