Differences in biomechanical and metabolic factors between patients with frozen shoulder and asymptomatic individuals. A cross-sectional study.

BACKGROUND: the pathogenesis of frozen shoulder (FS) is thought to be one of inflammation and fibrosis possibly influenced by hyperglycemia. Biomechanical changes of the shoulder joint in terms of muscle strength, scapular kinematics and proprioception might occur in FS. OBJECTIVES: to compare muscle strength, scapular kinematics, proprioception, and blood glucose levels within patients with FS and to asymptomatic individuals. DESIGN: cross-sectional study. METHOD: Thirty-five patients with FS and 35 asymptomatic age and gender-matched individuals underwent physical assessment to determine muscle strength (abduction, external and internal rotation), scapular kinematics (both visually and with a plurimeter), proprioception (joint position sense), and blood glucose level. RESULTS: Patients with FS showed a decrease in muscle strength in their affected shoulder compared to both the unaffected shoulder and asymptomatic individuals. Significant differences were found between the affected and unaffected shoulder in the FS group and between groups (FS versus controls) in scapular upward rotation (plurimeter) at 30° and 60° abduction. No difference in scapular kinematics (visual observation), proprioception, and blood glucose levels was found neither between shoulders in the FS group nor between groups. CONCLUSION: A clinically relevant difference in muscle strength and increase in scapular upward rotation were found in the affected shoulder of patients with FS compared to their unaffected side and controls. However, no evidence of different levels of scapular kinematics (visual observation), proprioception, and blood glucose levels in the affected shoulder compared to the unaffected shoulder or controls is lacking.

Does the psychological profile of a patient with frozen shoulder predict future outcome? A systematic review.

BACKGROUND AND PURPOSE: Frozen shoulder (FS) is defined as a condition characterised by functional restriction and daily and nightly pain. As in other shoulder pathologies, the manifestation of psychological factors is recognised in FS; however, from a psychological point of view, only few studies have reported its prognostic value. The aim of this systematic review is to investigate, in patients with FS, the prognostic value of psychological factors on pain, function, disability, health-related quality of life, return to work and time to recovery. MATERIALS AND METHODS: This systematic review was reported following the Preferred Reporting Items for Systematic reviews and Meta-Analysis-PRISMA 2020 guideline. The authors followed the Cochrane Handbook for Systematic review of Intervention as methodological guidance. The Quality in Prognostic Studies-QUIPS tool was used to assess the risk of bias. RESULTS: Pain-related fear and depression could be prognostic regarding patient-reported outcome measures assessing shoulder function, disability, and pain; instead, pain catastrophizing could have a prognostic value assessed by the disability of the arm shoulder and hand -DASH scale. Anxiety would appear to impact on disability and pain. DISCUSSION AND CONCLUSIONS: As widely reported in numerous musculoskeletal conditions, also in FS psychological factors influence the physical dimension such as pain, disability and function. Therefore, clinicians should be encouraged to identify these factors through a comprehensive assessment of the bio-psychological profile of each individual with FS. Perhaps, patients with FS that show such psychological prognostic factors could benefit from a comprehensive and shared approach with other dedicated professionals.

Exercise into pain in chronic rotator cuff related shoulder pain: a prospective single-group feasibility study.

OBJECTIVES: This study evaluated the feasibility of exercising into pain in rotator cuff related shoulder pain (RCRSP), data collection procedures, feedback from physiotherapists and patients, and clinically important changes in patient-reported outcome measures (PROMs). DESIGN: Unblinded non-randomised single-group study. SETTING: Physiotherapy clinic in Belgium. PARTICIPANTS: Twelve patients with unilateral RCRSP for minimum 3 months, aged 18-65 years. INTERVENTIONS: Twelve weeks of four individualised exercises, with nine physiotherapist-led sessions with pain ratings 4-7 out of 10 on a verbal Numeric Pain Rating Scale for 9 weeks and then pain ratings 0-2 for 3 weeks. Every physiotherapy session included 15 min of manual therapy. Non-supervised exercises were: 2×/week in weeks with physiotherapy session, 3×/week in weeks without physiotherapy session. OUTCOME MEASURES: Primary: adherence, where patients were considered adherent with 78% (7/9 sessions) attendance for supervised sessions and 81% (22/27 sessions) completion for non-supervised exercises, and Shoulder Pain and Disability Index (SPADI); secondary: fear-avoidance behaviour, fear of pain, physical outcomes (strength, range of motion, scapular dyskinesis); others: ultrasound (US) imaging outcomes (acromionhumeral distance, supraspinatus tendon thickness, occupation ratio), global perceived effect (GPE). PROMs were collected via online survey, except for the GPE (via closed envelope). US measures were taken after physical measures. RESULTS: Adherence and adverse effects were analysed in patients who had the possibility to attend minimum seven supervised sessions (n=8): 88% of them adhered to supervised sessions, 50% to non-supervised exercises; none of them withdrew from the study, three of them obtained individual clinically important improvements in SPADI score above 20 points. The measurement protocol of physical and ultrasonographic outcomes took around 60 min. CONCLUSIONS: Adherence to supervised sessions was satisfactory, the adherence to non-supervised exercises must be improved. Data collection procedures were feasible to perform, but some changes are recommended. TRIAL REGISTRATION NUMBER: NCT04154345.

Effectiveness of electrophysical agents in subjects with frozen shoulder: a systematic review and meta-analysis.

PURPOSE: This systematic review with meta-analysis aimed to assess the effectiveness of electrophysical agents in improving pain, function, disability, range of motion, quality of life, perceived stiffness, and time to recovery in subjects with frozen shoulder (FS). METHODS: A thorough search of MEDLINE, Cochrane Library, PEDro, and EMBASE yielded 1143 articles, of which 23 randomized controlled trials were included. Risk of bias (RoB) was assessed through Cochrane Risk of Bias 2 tool. The certainty of evidence was evaluated through the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). RESULTS: The analysis included a total of 1073 subjects. None of the studies were judged as low RoB. Potentially clinically significant differences were observed in pain at 6 weeks and 5 months after extracorporeal shockwave therapy (ESWT), and in disability up to 3 months with laser therapy, albeit with uncertain results due to the high RoB and to the study heterogeneity. Ultrasound (US) therapy did not yield significant differences in any outcomes. The certainty of evidence was very low. CONCLUSIONS: Based on the high heterogeneity and low quality and certainty of evidence, ESWT, laser, and US cannot be recommended for FS treatment. Caution should be exercised in interpreting the findings.

Although a clinical difference in pain and disability was observed, the certainty of the evidence was low.Ultrasound therapy is not recommended in patients with frozen shoulder.Electrophysical agents may not ensure adequate therapeutic efficacy.

Efficacy of combined strategies of physical activity, diet and sleep disorders as treatment in patients with chronic shoulder pain. A systematic review.

Introduction: The objective of this systematic review was to analyze the existing scientific evidence on the influence of dietary strategies, exercise, and sleep disorders on the symptomatology of patients with chronic shoulder pain, as well as to assess the methodological quality of the literature collected. Methods: The selection criteria were as follows: we included randomized controlled clinical trials written in English that investigated the effects of such interventions in patients with chronic shoulder pain and excluded studies where pre-operative rehabilitation or rehabilitation combined with corticosteroid injections was performed. We searched six databases Pubmed, Cochrane Library, Web of Science, CINAHL, Sportdiscus and Scopus, using the keywords "shoulder pain," "fasting," "physical therapy modalities," "rehabilitation," "exercise," "circadian clocks," and "chronic pain" to select randomized controlled clinical trials conducted in humans and written in English. The last search was conducted on 24/01/2023. (PROSPERO:CRD42023379925). Results: We used the tool proposed by the Cochrane Handbook to assess the risk of bias in the included studies of the 17 studies included, nine had a high risk of bias, two studies had an unclear risk of bias, and the remaining six studies had a low risk of bias. A total of 17 articles were selected, including 10 studies that showed a positive influences of exercise on chronic shoulder pain and five studies that showed a negative influence of sleep disorders on this patient profile. The remaining two articles analyzed the influence of nutritional strategies and metabolic problems in patients with chronic shoulder pain. The total sample size of the 17 included articles amounted to 9,991 individuals. Discussion: Studies confirm that exercise generates a hypoalgesic effect that improves chronic shoulder pain, functionality, and quality of life. Although dietary strategies and sleep disorders are known to influence chronic shoulder pain, there is a lack of studies that conduct interventions on these problems to assess how chronic shoulder pain varies.

Exploration of the clinical course and longitudinal correlations in frozen shoulder: The role of autonomic function, central pain processing, and psychological variables. A longitudinal multicenter prospective observational study.

BACKGROUND: Altered central pain processing (CPP) and dysautonomia might play a role in the clinical course of frozen shoulder and psychological factors, like pain catastrophizing and hypervigilance, might influence clinical variables in frozen shoulder. OBJECTIVES: To explore the clinical course of frozen shoulder regarding CPP, dysautonomia, pain catastrophizing, and hypervigilance and to explore whether longitudinal correlations between these outcomes and pain intensity were present. DESIGN: prospective longitudinal observational study. METHOD: Participants with frozen shoulder were recruited at hospitals and general practitioner practices and followed for 9 months. They completed six questionnaires (about demographics, shoulder pain and disability, pain intensity, pain catastrophizing, pain hypervigilance, and autonomic symptoms) and underwent tactile sensitivity (allodynia), pressure pain thresholds (hyperalgesia), temporal summation, and conditioned pain modulation during four timeframes (3-month intervals). RESULTS: Initially, 149 participants with frozen shoulder were recruited and 88 completed all the measurements. An improvement from baseline to at least one follow-up measurement was found for shoulder pain and disability, pain intensity, pain catastrophizing, hypervigilance, and dysautonomia. A fair longitudinal correlation was found between pain intensity and catastrophizing and hypervigilance (r = 0.301-0.397). Poor longitudinal correlations were found between pain intensity and allodynia and hyperalgesia (r = -0.180-0.193), between pain catastrophizing and dysautonomia (r = 0.209) and between hypervigilance and hyperalgesia (r = -0.159). CONCLUSION: Patients with frozen shoulder showed an early improvement that flattened with time in several pain and psychological variables over the course of 9 months. However, autonomic symptoms rather showed a late improvement over 9 months.

Exploration of the clinical course of frozen shoulder: A longitudinal multicenter prospective study of functional impairments.

BACKGROUND: Contradictory evidence exists regarding the clinical course of frozen shoulder (FS). OBJECTIVES: To explore the clinical course of FS regarding disabilities, pain, range of motion (ROM), muscle strength, scapular upward rotation, and proprioception and to establish longitudinal correlations between these variables. METHODS: Patients with FS were prospectively followed for 9 months at 3-month intervals. Assessment included the Disabilities of the Arm, Shoulder and Hand questionnaire; visual analogue scale for pain; an inclinometer for shoulder external rotation (ER), internal rotation (IR), flexion, and abduction ROM, and scapular upward rotation and proprioception, as well as handheld dynamometry for muscle strength in shoulder abduction, ER, and IR. RESULTS: Initially, 149 patients (98 females; mean (SD) age 53 (9) years) were included, with 88 completing all follow-up assessments. Most variables showed early improvement in the clinical course of FS, particularly ER and IR at 90° abduction, which continued to improve from 6 to 9 months of follow-up. Associations were observed between disabilities and pain (r = 0.61), disabilities/pain and ROM (r=-0.62 to -0.59 and r=-0.47 to -0.39, respectively), disabilities/pain and muscle strength (r=-0.24 to -0.35 and r=-0.36 to -0.17, respectively), and between disabilities/pain and scapular upward rotation below shoulder level (r = 0.23 to 0.38 and r = 0.24 to 0.30, respectively). ROM correlated with muscle strength (r = 0.14 to 0.44), while both ROM and ER muscle strength correlated with scapular upward rotation below shoulder level (r=-0.37 to -0.23 and r=-0.17 to -0.12, respectively). Muscle strength correlated with scapular upward rotation above shoulder level (r = 0.28 to 0.38) and lift-off muscle strength correlated with joint repositioning (r=-0.17 to -0.15). CONCLUSION: Almost all factors improved in the early phase (3-6 months) after baseline assessment, while ER and IR ROM at shoulder level continued to improve long term.

Massive Irreparable Rotator Cuff Tears: Which Patients Will Benefit from Physiotherapy Exercise Programs? A Narrative Review.

Massive irreparable rotator cuff tears can cause significant shoulder pain, disability and reduction in quality of life. Treatment approaches can be operative or non-operative. Operative approaches include reverse total shoulder arthroplasty, arthroscopic debridement, partial rotator cuff repair, subacromial balloon spacers, superior capsule reconstruction, and tendon transfer procedures. Non-operative approaches include physiotherapy exercise programs and corticosteroid injections. There are no randomized controlled trials comparing the different treatment approaches. It is therefore challenging for clinicians to advise patients on what is their best treatment pathway. Physiotherapy exercise programs are less expensive and have lower risks for patients than surgical approaches. However, the success of physiotherapy in patients with massive irreparable rotator cuff tears is highly variable with published success rates of 32-96%. Several cohort studies have sought to identify if certain factors are predictive of success with physiotherapy. Several biomechanical factors were identified as possibly being related to a successful or unsuccessful outcome following physiotherapy, with complete tear of subscapularis demonstrating the strongest evidence. However, there were no appropriately designed prognostic studies. There has been a strong emphasis on biomechanical factors. Other domains such as psychosocial factors, which are important in similar patient populations, have not been explored. We recommend that further research is needed in this area and should include randomized controlled trials comparing treatment approaches and longitudinal prospective prognostic studies to identify predictors of treatment success.

The Place of Botulinum Toxin in Spastic Hemiplegic Shoulder Pain after Stroke: A Scoping Review.

Stroke is a common pathology worldwide, with an age-standardized global rate of new strokes of 150.5 per 100,000 population in 2017. Stroke causes upper motor neuron impairment leading to a spectrum of muscle weakness around the shoulder joint, changes in muscle tone, and subsequent soft tissue changes. Hemiplegic shoulder pain (HSP) is the most common pain condition in stroke patients and one of the four most common medical complications after stroke. The importance of the appropriate positioning and handling of the hemiplegic shoulder for prevention of HSP is therefore of high clinical relevance. Nevertheless, HSP remains a frequent and disabling problem after stroke, with a 1-year prevalence rate up to 39%. Furthermore, the severity of the motor impairment is one of the most important identified risk factors for HSP in literature. Spasticity is one of these motor impairments that is likely to be modifiable. After ruling out or treating other shoulder pathologies, spasticity must be assessed and treated because it could lead to a cascade of unwanted complications, including spastic HSP. In clinical practice, Botulinum toxin A (BTA) is regarded as the first-choice treatment of focal spasticity in the upper limb, as it gives the opportunity to target specifically selected muscles. It thereby provides the possibility of a unique patient tailored focal and reversible treatment for post stroke spasticity. This scoping review aims to summarize the current evidence of BTA treatment for spastic HSP. First, the clinical manifestation and outcome measures of spastic HSP will be addressed, and second the current evidence of BTA treatment of spastic HSP will be reviewed. We also go in-depth into the elements of BTA application that may optimize the therapeutic effect of BTA. Finally, future considerations for the use of BTA for spastic HSP in clinical practice and research settings will be discussed.

Reliability of coracohumeral distance and subcoracoid tendons in subacromial pain syndrome.

This study investigated the intra-rater reliability of a novice ultrasound (US) examiner and the inter-rater reliability of two examiners (novice, expert) in the measures of coracohumeral distance at rest (CHD) and at 60° of elevation without (CHD60) or with weights (CHD60w), tendon thickness of the long head of the biceps (LHB) and subscapularis (SCP). Twenty-one patients with subacromial pain syndrome (SAPS) and 20 asymptomatic participants were included. Intra and inter-rater reliability were tested with intraclass-correlation-coefficient (ICC), differences between raters were analyzed with Bland-Altman plots. Intra-rater reliability for CHD, CHD60 and CHD60w was excellent (ICC = 0.97-0.98) in asymptomatic participants, and good-to-excellent (0.88-0.93) in SAPS, while intra-rater reliability for LHB and SCP was good-to-excellent in asymptomatic participants (0.88-0.97) and in SAPS (0.90-0.92). Inter-rater reliability for CHD, CHD60 and CHD60w was moderate-to-good (0.70-0.90) in asymptomatic participants and good (0.85-0.87) in SAPS, in contrast inter-rater reliability for LHB and SCP was poor in asymptomatic participants (0.10-0.46) and poor-to-moderate (0.49-0.61) in SAPS. Bland-Altman plots revealed systematic and/or proportional bias for tendons' thickness. A novice showed good-to-excellent intra-rater reliability in all US measures, whereas in comparison to an expert a novice can measure reliably CHD, CHD60 and CHD60w, but not LHB and SCP, where more training is recommended.

Subacromial space measured by ultrasound imaging in asymptomatic subjects and patients with subacromial shoulder pain: an inter-rater reliability study.

BACKGROUND: Acromiohumeral distance (AHD) and supraspinatus tendon thickness (STT) measured by ultrasound (US) can be combined in the occupation ratio (OR). Inter-rater reliability on these subacromial measures depends on the US experience of raters and on the subject status, differing between asymptomatic or patients with subacromial shoulder pain (SSP). OBJECTIVE: To evaluate inter-rater reliability between two raters with different US experience (experienced examiner and novice examiner). METHODS: In total, 20 asymptomatic subjects (controls) and 21 patients with SSP were examined on one shoulder. Inter-rater reliability was evaluated with intraclass correlation coefficient (ICC). RESULTS: ICC for controls was good for AHD at rest and at 60° (0.76-0.77), moderate for STT and AHD at 60° with weights (0.53-0.72), while OR was poorly reliable (below 0.44). ICC for SSP was moderate for AHD at rest and at 60°, STT, OR at rest and at 60° (0.52-0.74) and poor for AHD at 60° with weights and OR at 60° with weights (0.33-0.36). Bland-Altman plots showed systematic bias. CONCLUSION: Inter-rater reliability varied largely from poor to good between two examiners with different US experience. Clinicians might use the US as additional tool for detecting the subacromial structures, but a structured training including also symptomatic subjects is suggested. Researchers may further investigate the OR in matched case-control studies, and an overall agreement phase is recommended before starting the inter-rater reliability phase.

Differences in Coracohumeral Distance Between the Symptomatic and the Asymptomatic Shoulder in Patients With Unilateral Shoulder Pain and in Healthy Participants: A Cross-Sectional Study.

OBJECTIVES: The aim of this study was to analyze whether differences in the coracohumeral distance (CHD) exist between the symptomatic and the asymptomatic shoulder in patients with subacromial pain syndrome and compare with the shoulder of control participants. METHODS: This was a cross-sectional, observational study. A sample comprising 62 participants with subacromial pain syndrome was recruited from 3 different primary care centers. The CHD was determined from standardized ultrasonography measures performed on both shoulders at 0° and 60° of shoulder abduction, whereas the dominant arm was measured for the control participants. RESULTS: Statistically significant differences in CHD at 0° and 60° were found between the symptomatic and control shoulders (P = .011/P = .002) and between the contralateral asymptomatic shoulder and controls (P = .026/P = .007). CONCLUSION: We found differences in CHD at 0° and 60° of shoulder elevation between both the affected and the nonaffected shoulders when compared with healthy shoulders. These results suggest that CHD may be a contributing factor in chronic shoulder pain.

Understanding the clinical profile of patients with frozen shoulder: a longitudinal multicentre observational study.

INTRODUCTION: There is a large diversity in the clinical presentation of frozen shoulder (FS) and the clinical outcome is not always satisfactory. The aim of the current study was to examine to what extent range of motion (ROM) limitation, metabolic factors (diabetes mellitus and thyroid disorders), autonomic symptoms and pain sensitivity may contribute to the prognosis in terms of shoulder pain and disability and quality of life in patients with FS. METHODS: Patients with stage 1 or 2 FS were longitudinally followed-up during 9 months after baseline assessment. They completed six questionnaires and underwent quantitative sensory testing (pressure pain thresholds, temporal summation and conditioned pain modulation) and ROM assessment. RESULTS: One hundred and forty-nine patients with FS were initially recruited and 121 completed at least one follow-up measurement. Shoulder pain and disability improved over time and diabetes mellitus was found to be a prognostic factor for final outcome. Several domains of quality of life also improved over time and external rotation ROM, diabetes mellitus, thyroid disorder and autonomic symptoms were found to be prognostic factors for final outcome. These prognostic factors explained 2.5%-6.3% of the final outcome of shoulder pain and disability and quality of life. DISCUSSION AND CONCLUSION: In patients with FS, prognostic variables were able to predict different outcomes, indicating that outcomes in this population can be variable-dependent. Other variables not explored in this study might contribute to the prognosis of patients with FS, which should be investigated in future research. In clinical practice, baseline assessment of prognostic factors and focusing on a more holistic approach might be useful to inform healthcare practitioners about progression of patients with FS during a 9-month period.

An Instrument-Assisted Coracoid Pain Test: An Exploratory Diagnostic Accuracy Study.

The coracoid pain test (CPT) could contribute to the diagnosis of frozen shoulder (FS) with palpation. However, due to assessor performance these values might be unreliable. Therefore, the aim was to explore the diagnostic accuracy of an instrument-assisted CPT and two alternative approaches (pain severity and side comparison) for assistance in the diagnosis of FS. Patients with FS and healthy age-matched controls were recruited. All participants underwent the instrument-assisted CPT on both shoulders with a pressure algometer. Sensitivity, specificity, and likelihood ratios were determined for the three approaches. In total, 35 patients with FS and 35 healthy participants were included. The original approach was positive in eight participants (11.4%), with only sufficient specificity to draw a conclusion. The pain severity approach was positive in 31 participants (44.3%) with sufficient sensitivity, specificity and likelihood ratios. The side comparison approach was positive in 10 participants (14.3%) with excellent specificity and positive likelihood ratio. The specificity of the instrument-assisted CPT can be used to increase the probability of FS with both the original and alternative approaches. Only the pain severity approach can draw a conclusion with a negative test result. This study should be repeated with a cross-sectional design to strengthen and confirm the conclusions.

Autonomic Nervous System Function and Central Pain Processing in People With Frozen Shoulder: A Case-control Study.

OBJECTIVES: The pathophysiology of a frozen shoulder (FS) is thought to be related to chronic inflammation. Chronic inflammation may disturb the immune system and consequently the nervous system as part of an overarching system. The aim of this study was to determine the presence of disturbed autonomic nervous system function and altered central pain processing (CPP) in patients with FS. Secondarily, the presence of psychological variables (catastrophizing and hypervigilance) and self-reported associated symptoms of altered CPP in patients with FS were investigated. METHODS: Patients with FS and healthy controls completed the Composite Autonomic Symptom Score (autonomic function) and underwent quantitative sensory testing to assess tactile sensitivity (ie, allodynia), pressure pain thresholds (PPTs, ie, hyperalgesia), temporal summation of pain, and Conditioned Pain Modulation (CPM). Psychological issues were explored with the Pain Catastrophizing Scale and the Pain Vigilance and Awareness Questionnaire, and self-reported symptoms associated with altered CPP were determined with the Central Sensitization Inventory. RESULTS: Thirty-two patients with FS and 35 healthy controls were analyzed in the study. Patients with FS showed more self-reported autonomic symptoms and symptoms of altered CPP, higher levels of pain catastrophizing and hypervigilance, and are more sensitive to tactile touches and mechanical pressure compared with controls. DISCUSSION: On the basis of the effect sizes, between-group differences in allodynia, hyperalgesia, catastrophizing, and hypervigilance were clinically relevant, but only local allodynia, hyperalgesia, catastrophizing, and hypervigilance were statistically different. Therefore, obvious altered CPP was not present at the group level in patients with FS compared with controls.

Frozen shoulder.

Frozen shoulder is a common debilitating disorder characterized by shoulder pain and progressive loss of shoulder movement. Frozen shoulder is frequently associated with other systemic conditions or occurs following periods of immobilization, and has a protracted clinical course, which can be frustrating for patients as well as health-care professionals. Frozen shoulder is characterized by fibroproliferative tissue fibrosis, whereby fibroblasts, producing predominantly type I and type III collagen, transform into myofibroblasts (a smooth muscle phenotype), which is accompanied by inflammation, neoangiogenesis and neoinnervation, resulting in shoulder capsular fibrotic contractures and the associated clinical stiffness. Diagnosis is heavily based on physical examination and can be difficult depending on the stage of disease or if concomitant shoulder pathology is present. Management consists of physiotherapy, therapeutic modalities such as steroid injections, anti-inflammatory medications, hydrodilation and surgical interventions; however, their effectiveness remains unclear. Facilitating translational science should aid in development of novel therapies to improve outcomes among individuals with this debilitating condition.

Are psychosocial variables, sleep characteristics or central pain processing prognostic factors for outcome following rotator cuff repair? A protocol for a prospective longitudinal cohort study.

INTRODUCTION: Prognosis following surgical rotator cuff repair (RCR) is often established through the assessment of non-modifiable biomedical factors such as tear size. This understates the complex nature of recovery following RCR. There is a need to identify modifiable psychosocial and sleep-related variables, and to find out whether changes in central pain processing influence prognosis after RCR. This will improve our knowledge on how to optimise recovery, using a holistic rehabilitation approach. METHODS AND ANALYSIS: This longitudinal study will analyse 141 participants undergoing usual care for first time RCR. Data will be collected 1-21 days preoperatively (T1), then 11-14 weeks (T2) and 12-14 months (T3) postoperatively. We will use mixed-effects linear regression to assess relationships between potential prognostic factors and our primary and secondary outcome measures-the Western Ontario Rotator Cuff Index; the Constant-Murley Score; the Subjective Shoulder Value; Maximal Pain (Numeric Rating Scale); and Quality of Life (European Quality of Life, 5 dimensions, 5 levels). Potential prognostic factors include: four psychosocial variables; pain catastrophising, perceived stress, injury perceptions and patients' expectations for RCR; sleep; and four factors related to central pain processing (central sensitisation inventory, temporal summation, cold hyperalgesia and pressure pain threshold). Intercorrelations will be assessed to determine the strength of relationships between all potential prognostic indicators.Our aim is to explore whether modifiable psychosocial factors, sleep-related variables and altered central pain processing are associated with outcomes pre-RCR and post-RCR and to identify them as potential prognostic factors. ETHICS AND DISSEMINATION: The results of the study will be disseminated at conferences such as the European Pain Congress. One or more manuscripts will be published in a peer-reviewed SCI-ranked journal. Findings will be reported in accordance with the STROBE statement and PROGRESS framework. Ethical approval is granted by the Ethical commission of Canton of Zurich, Switzerland, No: ID_2018-02089 TRIAL REGISTRATION NUMBER: NCT04946149.

Factors associated with better treatment outcome of physical therapy interventions after shoulder arthroplasty: A systematic review.

OBJECTIVE: To summarize factors that are associated with a better treatment outcome after post-operative physical therapy in patients with shoulder arthroplasty. DATA SOURCES: PubMed, Cochrane, and Web of Science. REVIEW METHODS: Studies examining factors that are associated with a better outcome after post-operative physical therapy interventions in patients with shoulder arthroplasty were included. Two independent reviewers performed screening, extracted data, and assessed the risk of bias and level of evidence, using the Quality In Prognosis Studies tool and Evidence-Based Guideline Development checklist. PRISMA guidelines were followed. RESULTS: In total, 460 articles were found and 14 studies were included. Two of the included articles had a moderate risk of bias, 12 high. The overall number of patients in the included studies varied from 20 to 2053. Patients had either a reverse (N = 1863), an anatomic total shoulder arthroplasty (N = 1029) or, a hemiarthroplasty (N = 133). Anatomic total shoulder arthroplasty patients with a neutral rotation sling position showed less night pain and greater range of motion, which was awarded moderate evidence. Other modifiable and non-modifiable factors such as telemedicine, immediate range of motion exercises, and pre-operative function were only awarded preliminary or conflicting evidence. CONCLUSION: Mainly preliminary and conflicting evidence was found. The possible causes of the conflicting evidence were the different measurement methods, implant types, and follow-up times used. The methodological quality was low and physical therapy protocols differed greatly. More high-quality research with standardized protocols is needed to determine the association of various factors with treatment outcomes after post-operative physical therapy in patients with shoulder arthroplasty.

Causes of Shoulder Dysfunction in Diabetic Patients: A Review of Literature.

Objective: Understanding the underlying mechanisms behind shoulder dysfunctions in patients with diabetes mellitus. Study Design: Systematic qualitative literature review. Participants: Patients with shoulder dysfunctions and diagnosed with impaired glucose tolerance or diabetes mellitus. Intervention: Published scientific literature containing evidence about the mechanisms of shoulder dysfunctions in the diabetic population. Articles were selected based on criteria containing diabetic population, shoulder dysfunction, methodological quality ≥ 6/9 and >20 subjects. Main Outcome measures: range of motion; questionnaires (QoL, UCLA-m, SPADI, DASH); blood glucose, blood HbA1C; calculated capsular stiffness (Kcap); calcification shoulder joint; shoulder dysfunction in patients with glucose metabolism disorders and diabetes mellitus. Results: We found 17 published articles with level 2 and 3 evidence. Multiple factors such as age, duration of diabetes mellitus (DM), glycated hemoglobin (HbA1c), advanced glycation end products (AGE), vascular endothelial growth factor (VEGF), interleukin-1ß (IL-1ß) were shown to be associated with tendon changes and increased capsular stiffness (Kcap) conceivably leading to limited range of motion (ROM) or frozen shoulder. Decreased ROM and frozen shoulder have a significantly higher prevalence in DM than in non-DM. Conclusions: Based on the current literature we confirm a high prevalence of shoulder dysfunctions in patients with diabetes mellitus. The cause of the shoulder complications is unknown, and more research is mandatory to shed more light on the complex interplay between the multifactorial causes of shoulder dysfunction in diabetes mellitus.