Marked innervation but also signs of nerve degeneration in between the Achilles and plantaris tendons and presence of innervation within the plantaris tendon in midportion Achilles tendinopathy

Objectives:

The plantaris tendon is increasingly recognised as an important factor in midportion Achilles tendinopathy. Its innervation pattern is completely unknown.

Methods:

Plantaris tendons (n=56) and associated peritendinous tissue from 46 patients with midportion Achilles tendinopathy and where the plantaris tendon was closely related to the Achilles tendon were evaluated. Morphological evaluations and stainings for nerve markers [general (PGP9.5), sensory (CGRP), sympathetic (TH)], glutamate NMDA receptor and Schwann cells (S-100β) were made.

Results:

A marked innervation, as evidenced by evaluation for PGP9.5 reactions, occurred in the peritendinous tissue located between the plantaris and Achilles tendons. It contained sensory and to some extent sympathetic and NMDAR1-positive axons. There was also an innervation in the zones of connective tissue within the plantaris tendons. Interestingly, some of the nerve fascicles showed a partial lack of axonal reactions.

Conclusion:

New information on the innervation patterns for the plantaris tendon in situations with midportion Achilles tendinopathy has here been obtained. The peritendinous tissue was found to be markedly innervated and there was also innervation within the plantaris tendon. Furthermore, axonal degeneration is likely to occur. Both features should be further taken into account when considering the relationship between the nervous system and tendinopathy.     

Proteomics Perspectives in Rotator Cuff Research: A Systematic Review of Gene Expression and Protein Composition in Human Tendinopathy

Background

Rotator cuff tendinopathy including tears is a cause of significant morbidity. The molecular pathogenesis of the disorder is largely unknown. This review aimed to present an overview of the literature on gene expression and protein composition in human rotator cuff tendinopathy and other tendinopathies, and to evaluate perspectives of proteomics – the comprehensive study of protein composition - in tendon research.

Materials and Methods

We conducted a systematic search of the literature published between 1 January 1990 and 18 December 2012 in PubMed, Embase, and Web of Science. We included studies on objectively quantified differential gene expression and/or protein composition in human rotator cuff tendinopathy and other tendinopathies as compared to control tissue.

Results

We identified 2199 studies, of which 54 were included; 25 studies focussed on rotator cuff or biceps tendinopathy. Most of the included studies quantified prespecified mRNA molecules and proteins using polymerase chain reactions and immunoassays, respectively. There was a tendency towards an increase of collagen I (11 of 15 studies) and III (13 of 14), metalloproteinase (MMP)-1 (6 of 12), -9 (7 of 7), -13 (4 of 7), tissue inhibitor of metalloproteinase (TIMP)-1 (4 of 7), and vascular endothelial growth factor (4 of 7), and a decrease in MMP-3 (10 of 12). Fourteen proteomics studies of tendon tissues/cells failed inclusion, mostly because they were conducted in animals or in vitro.

Conclusions

Based on methods, which only allowed simultaneous quantification of a limited number of prespecified mRNA molecules or proteins, several proteins appeared to be differentially expressed/represented in rotator cuff tendinopathy and other tendinopathies. No proteomics studies fulfilled our inclusion criteria, although proteomics technologies may be a way to identify protein profiles (including non-prespecified proteins) that characterise specific tendon disorders or stages of tendinopathy. Thus, our results suggested an untapped potential for proteomics in tendon research.     

关节镜下同期行冻结肩松解术对肩袖损伤患者的治疗效果评估

目的:评估关节镜下同期行冻结肩松解术对肩袖损伤患者的治疗效果。方法:选择2015年3月到2018年3月在我院诊治的肩袖损伤患者70例进行研究,按随机数表法将其分为观察组(n=36)和对照组(n=34)。对照组采用传统小切口肩袖修复术治疗,观察组采用关节镜下同期行冻结肩松解术进行治疗。比较两组治疗后疗效、手术时间、术中出血量、住院时间、疼痛减轻时间、治疗前后VAS、美国肩肘外科协会评分(ASES)、Contant-Muley评分的变化情况。结果:治疗后,观察组总有效率为94.44%,显著高于对照组(73.53%,P0.05);观察组手术时间、术中出血量、住院时间及疼痛减轻时间均显著低于对照组(P0.05);两组VAS、ASES、Contant-Muley评分较治疗前均显著改善(P0.05),且观察组VAS评分明显低于对照组,ASES及Contant-Muley评分显著高于对照组(P0.05)。结论:关节镜下同期行冻结肩松解术治疗肩袖损伤的临床疗效显著优于传统小切口肩袖修复术治疗,其可显著促进关节功能恢复,并减轻患者痛苦。     

General Practitioner Management of Shoulder Pain in Comparison with Rheumatologist Expectation of Care and Best Evidence: An Australian National Survey

Objectives

To determine whether current care for common shoulder problems in Australian general practice is in keeping with rheumatologist expectations and the best available evidence.

Methods

We performed a mailed survey of a random sample of 3500 Australian GPs and an online survey of all 270 rheumatologists in Australia in June 2009. Each survey included four vignettes (first presentation of shoulder pain due to rotator cuff tendinopathy, acute rotator cuff tear in a 45 year-old labourer and early and later presentation of adhesive capsulitis). For each vignette, GPs were asked to indicate their management, rheumatologists were asked to indicate appropriate primary care, and we determined best available evidence from relevant Cochrane and other systematic reviews and published guidelines.

Results

Data were available for at least one vignette for 614/3500 (17.5%) GPs and 64 (23.8%) rheumatologists. For first presentation of rotator cuff tendinopathy, 69% and 82% of GPs and 50% and 56% rheumatologists would order a shoulder X-ray and ultrasound respectively (between group comparisons P = 0.004 and P<0001). Only 66% GPs and 60% rheumatologists would refer to an orthopaedic surgeon for the acute rotator cuff tear. For adhesive capsulitis, significantly more rheumatologists recommended treatments of known benefit (e.g. glucocorticoid injection (56% versus 14%, P<0.0001), short course of oral glucocorticoids (36% versus 6%, p<0.0001) and arthrographic distension of the glenohumeral joint (41% versus 19%, P<0.0001).

Conclusions

There is a mismatch between the stated management of common shoulder problems encountered in primary care by GPs, rheumatologist expectations of GP care and the available evidence.     

Development of an Arthroscopic Joint Capsule Injury Model in the Canine Shoulder

Background

The natural history of rotator cuff tears can be unfavorable as patients develop fatty infiltration and muscle atrophy that is often associated with a loss of muscle strength and shoulder function. To facilitate study of possible biologic mechanisms involved in early degenerative changes to rotator cuff muscle and tendon tissues, the objective of this study was to develop a joint capsule injury model in the canine shoulder using arthroscopy.

Methods

Arthroscopic surgical methods for performing a posterior joint capsulectomy in the canine shoulder were first defined in cadavers. Subsequently, one canine subject underwent bilateral shoulder joint capsulectomy using arthroscopy, arthroscopic surveillance at 2, 4 and 8 weeks, and gross and histologic examination of the joint at 10 weeks.

Results

The canine subject was weight-bearing within eight hours after index and follow-up surgeries and had no significant soft tissue swelling of the shoulder girdle or gross lameness. Chronic synovitis and macroscopic and microscopic evidence of pathologic changes to the rotator cuff bony insertions, tendons, myotendinous junctions and muscles were observed.

Conclusions

This study demonstrates feasibility and proof-of-concept for a joint capsule injury model in the canine shoulder. Future work is needed to define the observed pathologic changes and their role in the progression of rotator cuff disease. Ultimately, better understanding of the biologic mechanisms of early progression of rotator cuff disease may lead to clinical interventions to halt or slow this process and avoid the more advanced and often irreversible conditions of large tendon tears with muscle fatty atrophy.     

Recent advances in shoulder research

Shoulder pathology is a growing concern for the aging population, athletes, and laborers. Shoulder osteoarthritis and rotator cuff disease represent the two most common disorders of the shoulder leading to pain, disability, and degeneration. While research in cartilage regeneration has not yet been translated clinically, the field of shoulder arthroplasty has advanced to the point that joint replacement is an excellent and viable option for a number of pathologic conditions in the shoulder. Rotator cuff disease has been a significant focus of research activity in recent years, as clinicians face the challenge of poor tendon healing and irreversible changes associated with rotator cuff arthropathy. Future treatment modalities involving biologics and tissue engineering hold further promise to improve outcomes for patients suffering from shoulder pathologies.     

The Influence of Arm Swelling Duration on Shoulder Pathology in Breast Cancer Patients with Lymphedema

Purpose

To evaluate the pathological effect of the duration of arm swelling on the shoulder pathology in patients with breast cancer-related lymphedema.

Methods

Forty seven breast cancer patients with unilateral arm lymphedema were assessed. The duration of the arm swelling and shoulder pain were recorded. Ultrasound examination of the shoulder joint was performed in all patients to detect any lesions.

Results

Abnormalities were detected by ultrasound in 41/47 (87.2%) study participants. Subacromial subdeltoid bursal thickening was found in 26/47 (55.3%) participants, distension of the biceps brachii tendon sheath was found in 14/47 (29.8%) and a supraspinatus tendon tear was found in 13/47 (27.7%). Patients with a supraspinatus tendon tear were found to have a significantly longer duration of lymphedema (1310 days vs. 398 days, p = 0.032).

Conclusions

The duration of arm lymphedema has a progressive pathological effect on rotator cuff. Clinicians should adopt an early management approach of shoulder pain in patients with breast cancer-related lymphedema.     

Biceps tenotomy in the presence of a supraspinatus tear alters the adjacent intact tendons and glenoid cartilage

A rotator cuff tear is a common injury in athletes and workers who repeatedly perform overhead movements, and it is not uncommon for this demographic to return to activity shortly after treatment. A biceps tenotomy is often performed in the presence of a rotator cuff tear to help reduce pain and improve joint function. However, the effect of this procedure on the surrounding tissues in the glenohumeral joint is unknown. Therefore, the purpose of this study was to investigate the effect of a biceps tenotomy in the presence of a supraspinatus rotator cuff tear followed by overuse activity on ambulatory function and mechanical and histologic properties of the remaining rotator cuff tendons and glenoid cartilage. 46 rats underwent 4 weeks of overuse activity to create a tendinopathic condition, then were randomized into two groups: unilateral detachment of the supraspinatus tendon or detachment of the supraspinatus and long head of the biceps tendons. Ambulatory measurements were performed throughout the 8 weeks prior to euthanasia, followed by analysis of the properties of the remaining intact tendons and glenoid cartilage. Results demonstrate that shoulder function was not effected in the biceps tenotomy group. However, the intact tendons and glenoid cartilage showed altered mechanical and histologic properties. This study provides evidence from an animal model that does not support the use of tenotomy in the presence of a supraspinatus tendon rotator cuff tear, and provides a framework for physicians to better prescribe long-term treatment strategies for patients.     

肩袖间隙影像解剖及常见病变的研究进展

肩袖间隙在解剖学上是肩关节的一个复合区域,在维持肩关节稳定性和保护肱二头肌长头肌腱功能起重要作用。对肩袖间隙解剖结构及功能的深入认识有助于肩袖间隙损伤性病变、挛缩性病变等的及时诊断和合理治疗。影像学检查尤其是磁共振逐步成为肩袖间隙疾病最主要的检查方法,包括常规扫描、直接及间接性磁共振肩关节造影、增强扫描等。本文将就肩袖间隙的影像解剖及常见病变的相关研究进行综述。     

Treatment of lesions of the rotator cuff

The impingement syndrome and tendinopathy of the rotator cuff are the most common causes (complaints) of pain and disability of the shoulder. The aim of this study is to evaluate the efficacy of a specific rehabilitative protocol, integrated with the administration of a nutritional supplement, in the conservative rehabilitative treatment, as well as in post-surgery, of patients with lesions of the rotator cuff. Two groups with syndrome of the rotator cuff were formed to follow different therapeutic courses, in relation to the choice of each subject to undergo the conservative treatment (Arm A) or the surgical one (Arm B). In Arm A the study included the association of therapy with ESWT (shock waves) with the proprioceptive Multi Joint System, for rehabilitating joint movement and muscle strength of the shoulder, and a specific nutritional supplement to reduce the pain and conserve the cartilage tissue. Between February 2009 and June 2009, we enrolled 30 subjects (randomized into three homogenous groups A1, A2, A3), average age 45±10 years, with rotator cuff syndrome with calcification of the shoulder, diagnosed through clinical examination and investigative instruments (X-ray, echography or NMR). In Arm B, from September 2009 to January 2010, we enrolled 50 patients (randomized into two groups, B1 and B2), 24 male (average age 58.4: min 28 and max 78) and 26 females (average age 59.5: min 30 and max 80), who had undergone rotator cuff operations and acromionplasty for non-massive lesions without important gleno-humeral instability, with either open or arthroscopic procedures. The analysis of the results of Arm A highlights that in terms of reducing pain the main benefits were found in Group A1 where the supplement was given. From the analysis of the data of Arm B, in both groups an improvement of the first 4 items evaluated was evident. In Group B1, 84 percent of the patients declared to be satisfied and improved and 16 percent were dissatisfied; in Group B2, where the nutritional supplement was given, 92 percent were satisfied and 8 percent were dissatisfied. In conclusion, we retain that in cases of rotator cuff syndrome, an integrated rehabilitative approach, whether conservative or post-surgical, directed at taking total control of the patient, must observe particular attention to the optimization of the articular tissular metabolic balance in order to favour better functional recovery.     

Effect of Bone Mineral Density on Rotator Cuff Tear: An Osteoporotic Rabbit Model

IntroductionAn increased bone mineral density (BMD) in the proximity to tendon insertion can improve rotator cuff repair and healing. However, how a decrease of BMD in the humeral head affects the biomechanical properties of the rotator cuff tendon is still unclear. Previous studies have demonstrated ovariectomy in animals to lead to osteoporosis and decreased BMD, and Teriparatide (PTH) administration to improve BMD and strength of bone. This study aimed to explore the correlation between humeral head BMD and infraspinatus (ISP) tendon insertion strength, and if an increase in bone quantity of the humeral head can improve the strength of the rotator cuff.ResultsSignificant differences were observed in the measured humeral head BMD of the Control and OVX-PTH groups compared to the OVX-Saline group (P = 0.0004 and P = 0.0024, respectively). No significant difference was found in failure stress among the three groups, but an expected trend with the control group and OVX-PTH group presenting higher failure strength compared to the OVX-Saline group. BMD at the humeral head showed a positive linear correlation with stress (r² = 0.54). Histology results showed the superiority in OVX-PTH group ISP enthesis compared to the OVX-Saline group.ConclusionBone loss of the humeral head leads to decreased tendon/bone insertion strength of the infraspinatus tendon enthesis. Teriparatide administration can increase bone density of the humeral head and may improve the mechanical properties of the infraspinatus tendon enthesis.     

An MRI Study of Symptomatic Adhesive Capsulitis

Background

Appilication of MR imaging to diagnose Adhesive Capsulitis (AC) has previously been described. However, there is insufficient information available for the MRI analysis of AC. This study is to describe and evaluate the pathomorphology of the shoulder in Asian patients with AC compared to healthy volunteers.

Methodology/Principal Findings

60 Asian patients with clinically diagnosed AC and 60 healthy volunteers without frozen shoulder underwent MRI of the shoulder joint. All subjects who were age- and sex-matched control ones underwent routine MRI scans of the affected shoulder, including axial, oblique coronal, oblique sagittal T1WI SE and coronal oblique T2WI FSE sequences. Significant abnormal findings were observed on MRI, especially at the rotator cuff interval. The coracohumeral ligament (CHL), articular capsule thickness in the rotator cuff interval as well as the fat space under coracoid process were evaluated. MRI showed that patients with adhesive capsulitis had a significantly thickened coracohumeral ligament and articular capsule in the rotator cuff interval compared to the control subjects (4.2 vs. 2.4 mm, 7.2 vs. 4.4 mm; p<0.05). Partial or complete obliteration of the subcoracoid fat triangle was significantly more frequent in patients with adhesive capsulitis compared with control subjects (73% vs. 13%, 26% vs. 1.6%; p<0.001). Synovitis-like abnormality around the long biceps tendon was significantly more common in patients with adhesive capsulitis than in control subjects. With regards to the inter-observer variability, two MR radiologists had an excellent kappa value of 0.86.

Conclusions/Significance

MRI can be used to show characteristic findings in diagnosing AC. Thickening of the CHL and the capsule at the rotator cuff interval and complete obliteration of the fat triangle under the coracoid process have been shown to be the most characteristic MR findings seen with AC.     

The effect of glenohumeral plane of elevation on supraspinatus subacromial proximity

Shoulder pain is a common clinical problem affecting most individuals in their lifetime. Despite the high prevalence of rotator cuff pathology in these individuals, the pathogenesis of rotator cuff disease remains unclear. Position and motion related mechanisms of rotator cuff disease are often proposed, but poorly understood. The purpose of this study was to determine the impact of systematically altering glenohumeral plane on subacromial proximities across arm elevation as measures of tendon compression risk. Three-dimensional models of the humerus, scapula, coracoacromial ligament, and supraspinatus were reconstructed from MRIs in 20 subjects. Glenohumeral elevation was imposed on the humeral and supraspinatus tendon models for three glenohumeral planes, which were chosen to represent flexion, scapular plane abduction, and abduction based on average values from a previous study of asymptomatic individuals. Subacromial proximity was quantified as the minimum distance between the supraspinatus tendon and coracoacromial arch (acromion and coracoacromial ligament), the surface area of the supraspinatus tendon within 2 mm proximity to the coracoacromial arch, and the volume of intersection between the supraspinatus tendon and coracoacromial arch. The lowest modeled subacromial supraspinatus compression measures occurred during flexion at lower angles of elevation. This finding was consistent across all three measures of subacromial proximity. Knowledge of this range of reduced risk may be useful to inform future studies related to patient education and ergonomic design to prevent the development of shoulder pain and dysfunction.     

Radial extracorporeal shock wave therapy in the treatment of shoulder calcific tendinitis

Shoulder calcific lesions of the rotator cuff are a common problem in physiatric and orthopedic practice. The lesions are mostly located in the supraspinatus tendon, close to the insertion area in the critical zone. Patients are usually treated conservatively by nonsteroid antiinflammatory drugs, analgesic drugs, local injections, physiotherapy and rarely by applying surgical procedures. Painful shoulder gives rise to functional disabilities and may sometimes lead to pharmacological overuse. In the last twenty years, extracorporeal shock wave therapy (ESWT) has been frequently used in the treatment of calcific tendinopathies. We have evaluated the effectiveness of radial ESWT on the group of 30 patients, aged between 28 and 58 years, with calcific tendinitis of the shoulder. Criotherapy, medical exercises and radial ESWT were applied. We used the radial ESWT device (BTL-5000 SWT, Columbia, USA), 3 bars pressure, 10 Hz frequency, 2000 shocks. Patients were examined before the beginning of the treatment, immediately after the treatment, and 6 months later. The treatment included measurement of the range of motion (ROM), measurement of voluntary isometric contraction of shoulder muscles with manual muscle test (MMT), and subjective assessment of pain intensity with visual analogue scale (VAS). X-ray was done before and 6 month after treatment. The study has shown the efficiency of the treatment with radial ESWT. The level of statistical significance was determined with student t-test. Radial ESWT applied to patients with shoulder calcific lesions of the rotator cuff resulted in pain relief increase in the range of motion and increase in the muscular strength. As shown by X-ray, these results were followed by the decrease in the size of the rotator cuff calcifications.     

Vascular endothelial growth factor enhances tendon-bone healing by activating Yes-associated protein for angiogenesis induction and rotator cuff reconstruction in rats

Local angiogenesis following rotator cuff reconstruction is crucial for tendon-bone healing. The current research on the mechanism underlying angiogenesis that promotes tendon-bone healing is scarce. This study investigates the mechanism underlying vascular endothelial growth factor (VEGF)-Hippo signaling pathway's involvement in tendon-bone healing following rotator cuff reconstruction. Verteporfin, the inhibitor of the Yes-associated protein (YAP), was used to mechanically test and analyze two groups of tensile-failure loads following rotator cuff reconstruction and to detect collagen and angiogenesis-related marker expressions in the tendon. The interaction mechanism of the VEGF-Hippo signaling pathway was assessed using human umbilical vein endothelial cells (HUVECs). The diameter of the supraspinatus tendon reduced following verteporfin treatment. Mechanical tests revealed that verteporfin significantly reduces the tensile-failure load of the supraspinatus tendon. Verteporfin significantly reduces collagen 1 (Col 1), Col 3, Angiopoietin 2, CD31, Von Willebrand factor, CTGF, and CYR61 expressions. In HUVECs, VEGF activates VEGF receptors and inhibits LATS and YAP phosphorylation. YAP is then transferred to the nucleus to further activate downstream pathways. Therefore, verteporfin can inhibit VEGF-induced YAP pathway activation by inhibiting YAP activity. Angiogenesis in tendon-bone healing following rotator cuff reconstruction requires VEGF-Hippo signaling pathway synergy.     

点压按摩第二掌骨全息穴点联合冲击波治疗慢性肩袖损伤的临床研究

摘要 目的：探究点压按摩第二掌骨全息穴点联合冲击波治疗慢性肩袖损伤患者的临床疗效。方法：选取2019年1月-2019年12月本院接诊的122例慢性肩袖损伤患者展开研究,使用随机数字表法将两组患者随机分为研究组和常规组,每组患者均61例。给予常规组患者体外冲击波治疗,在常规组治疗的基础上给予研究组患者第二掌骨全息穴点点压按摩治疗。观察两组患者的临床疗效、美国加州大学肩关节评分量表(UCLA)评分、视觉疼痛模拟评分（VAS）、肩关节活动度(ROM)以及并发症的发生率。结果：研究组患者的总有效率显著高于常规组（P＜0.05）;治疗后,两组患者的UCLA评分均得到显著改善,且研究组患者改善优于常规组（P＜0.05）;两组患者的VAS评分显著降低,且研究组患者VAS评分显著低于常规组（P＜0.05）;两组患者的前屈、外展、体侧外旋ROM均优于治疗前,研究组患者ROM显著优于常规组（P＜0.05）。治疗后随访1年,研究组患者并发症发生率显著低于常规组（P＜0.05）。结论：第二掌骨全息穴点点压按摩结合冲击波治疗慢性肩袖损伤患者,可以提升患者的临床疗效,改善患者的肩关节功能,减轻疼痛,降低患者的并发症,具有较高的临床意义,值得在临床推广使用。     

The use of the long head of triceps interposition muscle flap for treatment of massive rotator cuff tears

Massive rotator cuff tears present a difficult problem for orthopedic surgeons. To address this problem, a long head of triceps muscle interposition flap was proposed. Ten patients underwent repair of massive rotator cuff tears using the triceps muscle flap. The patients' strength and range of motion were tested preoperatively, and a University of California, Los Angeles, shoulder score was assigned. Similar testing was performed 1 year later. Postoperatively, the patients showed significant improvement in the overall shoulder score and in the pain and function components of the score. There was no significant improvement in shoulder range of motion, except for shoulder flexion. An important finding was that there was no loss of strength in elbow extension following the loss of the long head of triceps muscle. It was concluded that the long head of triceps interposition flap is useful in the reconstruction of the massive rotator cuff tear.     

Supraspinatus tendon organizational and mechanical properties in a chronic rotator cuff tear animal model

Rotator cuff tears of the shoulder are a common cause of pain and disability. The successful repair of rotator cuff tendon tears depends on the time from onset of injury to the time of surgical repair. However, the effect of time from injury to repair remains poorly understood. A rat model was used to investigate the supraspinatus tendon organizational and mechanical property changes that occur with time post-injury to understand the natural injury response in the absence of repair. It was hypothesized that increased time post-injury would result in increased detrimental changes to tendon organizational and mechanical properties. Tendons were detached at the insertion on the humerus without repair and the quantitative organizational and mechanical properties were analyzed at 1, 2, 4, 8, and 16 weeks post-detachment. Tendon detachment resulted in a dramatic decrease in mechanical properties initially followed by a progressive increase with time. The quantitative collagen fiber orientation results provided corroborating support to the mechanical property data. Based on similarities in histology and mechanical properties to rotator cuff tears in humans, the animal model presented here is promising for future investigations of the tendon's natural injury response in the absence of repair.     

Scapulothoracic muscle activity and recruitment timing in patients with shoulder impingement symptoms and glenohumeral instability

BackgroundVarious studies have investigated scapulothoracic muscle activity and recruitment patterns in relation to shoulder complaints in different populations, but a consensus review is lacking.Hypothesis/purposeTo systematically review the state of the art regarding scapulothoracic muscle activity and recruitment timing in subjects with shoulder pain compared to pain free controls.Study designSystematic review.MethodsThe search for relevant articles was performed in Pubmed and Web of Science, including Web of Knowledge, using key words related to shoulder pain, scapulothoracic muscle activity or recruitment timing. Articles were included till November 2012. Case-control studies concerning the scapulothoracic region and muscle recruitment using electromyography (EMG) were included. Articles regarding rotator cuff muscles or neck-shoulder pathologies or studies handling a treatment outcome, were excluded. The methodological quality of the articles was assessed using appropriate risk of bias criteria for case-control studies.ResultsA total of 12 articles were included in the systematic review, containing patients with Shoulder Impingement Syndrome (SIS) or glenohumeral instability. In patients with SIS 3 out of 6 articles showed increased upper trapezius muscle (UT) activity, 3 out of 5 studies showed decreased lower trapezius muscle (LT) activity and 3 out of 5 articles showed decreased serratus anterior muscle (SA) activity. Patients with glenohumeral instability showed contradictory results on scapulothoracic muscle activity patterns. In both SIS and glenohumeral instability patients, no consensus was found on muscle recruitment timing.ConclusionPatients with SIS and glenohumeral instability display numerous variations in scapulothoracic muscle activity compared to healthy controls. In the SIS-group, the LT and SA muscle activity is decreased. In addition, the UT muscle activity is increased among the SIS patients, whereas no clear change is seen among patients with glenohumeral instability. Although the scapulothoracic muscle activity changed, no consensus could be made regarding muscle recruitment timing.     

Using support vector machines to optimally classify rotator cuff strength data and quantify post-operative strength in rotator cuff tear patients

Shoulder strength data are important for post-operative assessment of shoulder function and have been used in diagnosis of rotator cuff pathology. Support vector machines (SVM) employ complex analysis techniques to solve classification and regression problems. A SVM, a machine learning technique, can be used for analysis and classification of shoulder strength data. The goals of this study were to determine the diagnostic competency of SVM based on shoulder strength data and to apply SVM analysis in efforts to derive a single representative shoulder strength score. Data were taken from fourteen isometric shoulder strength measurements of each shoulder (involved and uninvolved) in 45 rotator cuff tear patients. SVM diagnostic proficiency was found to be comparable to reported ultrasound values. Improvement of shoulder function was accurately represented by a single score in pairwise comparison of the pre-operative and the 12 month post-operative group (P < 0.004). Thus, the SVM-based score may be a promising metric for summarizing rotator cuff strength data.