Incidence of shoulder pain in 40 years old and over and associated factors: A systematic review

The Critical Shoulder Angle: A Significant Radiological Measure in Rotator Cuff vs. Glenohumeral Osteoarthritis in Chilean Patients-A Descriptive Cross-Sectional Study

Background: Shoulder pain is one of the most important musculoskeletal conditions affecting the upper extremities. Glenohumeral osteoarthritis (GHOA) and rotator cuff injuries (RCIs) are notable for their high prevalence. The critical shoulder angle (CSA) is a significant radiological measure for determining the diagnosis and progression of patients with these conditions. Although there are reports in the international literature about this measure, in our country, guideline values considering these two pathologies are unknown. Objective: Our objective was to assess patients diagnosed with GHOA and RCI using an AP X-ray view and the CSA. Methods: To conduct this, we identified differences between sexes and age categories. Fifty-nine adult patients with GHOA and RCI were included. CSA grades varied depending on the age category and type of injury evaluated. Results: Significant differences between the age ranges of 40 and 54 (p = 0.05), 55-69 (p = 0.001), and 70-84 (p = 0.017) were observed. Conclusions: Patients with RCI tended to be younger and have a higher CSA compared to those with GHOA. It is important to have more normative values and to continue monitoring the critical shoulder angle in these patients.

Does the Keele STarT MSK tool predict the risk of poor outcome in non-specific shoulder complaints in primary care in a Dutch population?

OBJECTIVES

The Keele STarT MSK tool is a questionnaire to identify the prognostic factors for musculoskeletal conditions, such as shoulder complaints, developed by Keele University, UK. This study assessed whether the Keele STarT MSK tool can predict the risk of poor outcome in non-specific shoulder complaints in a Dutch population.

DESIGN

Multicentre prospective cohort study.

SETTING

Fourteen primary care physiotherapy clinics in the Netherlands participated in this study.

PARTICIPANTS

In total, 180 patients with non-specific shoulder complaints with complete data from the Keele STarT MSK tool (baseline), Short-Form 12 Health Survey (SF-12), Shoulder Pain and Disability Index (SPADI), Numeric Pain Rating Score (NPRS) and Global Perceived Effect (GPE) scale at week 6, week 12 or endpoint were included. Data were collected from January 2019 to January 2020. Of these, 180 patients were eligible for the study. Of these, 139 completed the study and were included in the analysis.

MAIN OUTCOME MEASURES

Poor outcome was defined as: SF-12 score ≤33 (physical health), SPADI score ≥30% (disability in activity), NPRS score ≥3 (pain intensity) and GPE scale score ≥3 (patient-reported recovery).

RESULTS

The area under the receiver operating characteristic curves for prediction of outcome were excellent for the SF-12, acceptable for the SPADI and NPRS, and showed no discrimination for the GPE scale. The optimal cut-off value for the Keele STarT MSK score to discriminate between low and medium/high risk groups was ≥5.

CONCLUSIONS

The Keele STarT MSK tool is able to predict the risk of poor outcome in patients with non-specific shoulder complaints in primary care physiotherapy clinics. Further research is needed to establish whether stratified care (subgrouping and targeted treatment) is more efficient. CONTRIBUTION OF PAPER.

Effect of a Novel Training Program in Patients With Chronic Shoulder Pain Based on Implicit Motor Learning: Pilot and Feasibility Study

Background

Implicit motor learning has been shown to be effective for learning sports-related motor skills. It facilitates automaticity of movements and thereby improves performance in multitasking and high-pressure environments. Motor learning to develop motor skills and neuroplastic capacities is not sufficiently incorporated in musculoskeletal rehabilitation. Especially in patients with chronic pain conditions like shoulder pain this approach might benefit over traditional exercise programs.

Purpose/hypothesis

The aim of this study was to investigate the feasibility and clinical outcome of a new implicit motor learning exercise program in a group of patients with chronic shoulder pain.

Study design

Pilot and feasibility cohort study.

Methods

Twenty-six patients with chronic shoulder pain performed a 6-week home exercise program with weekly remote follow up by a physiotherapist. The program comprised five exercises designed to challenge overall body balance, simultaneously engaging the upper limbs in a range of reaching tasks. The tasks included reaching above the head, at and below waist level, in various directions. No instructions on correct performance were provided to foster external focus. Feasibility was assessed by (1) recruitment rate, (2) follow up rate, (3) subjective experience, (4) self-reported adverse events and (5) self-reported adherence of subjects. Clinical effects of the program were assessed with (1) the Shoulder Pain and Disability Index (SPADI), (2) the Auto-Constant score, (3) the numeric rating scale (NRS) at rest and at night, (4) the patient specific functional scale (PSFS), (5) the avoidance endurance questionnaire (AEQ), (6) patient acceptable symptom state (PASS) and (7) a global rating of change (GROC).

Results

The study protocol was feasible in terms of follow up rate (16w for 28 patients), exercise adherence (77.1%± 29.41), and adverse events (no serious, 5 light adverse events). Statistically significant improvements were observed for SPADI (p<0.001), NRS at rest (p=0.033), at night (p=0.29), PSFS (p<0.001) and PASS (p<0.001) after only six weeks training.

Conclusion

This study reveals promising results of another way of looking at exercise for patients with chronic shoulder pain. Both feasibility and clinical effects of the program on pain and function was acceptable. Future studies should incorporate a control group, provide longer follow up and include objective measurements.

Level of evidence

2b.

Glenohumeral internal rotation deficit in general population with shoulder pain: A descriptive observational study

Glenohumeral internal rotation deficit (GIRD) is one of the most important factors influencing injury risk in the arm of overhead athletes. Some studies have shown that the GIRD of athletes with shoulder pain was higher than those without shoulder pain, establishing a relation between shoulder pain and GIRD. However, there are no studies that relate to GIRD and shoulder pain or the risk factors that affect GIRD in the population with this ailment. This study aimed to: determine if GIRD could be found clinically and between which values it oscillates in patients with shoulder pain, and explore if there are any potential associations between GIRD and some sociodemographic data, and orthopedic or radiological findings. A descriptive observational study design was adopted to determine if GIRD could be found clinically in patients with shoulder pain and to gain further evidence in the potential associations between GIRD and sociodemographic data, and orthopedic or radiological findings. All those patients without exclusion criteria between October 1,2020 and March 31,2021 were included. Exclusion criteria consisted of being under 18 years old but younger than 80 years old, showing shoulder pain in both shoulders and having a joint prosthesis in at least one of the 2 shoulders, tumor, or infection. A total of 67 patients aged between 25 and 75 years (52.7 ± 11.8 years, 36 male and 31 female). More than 82% of patients with shoulder pain showed a GIRD higher than 20º. The mean GIRD was 37.6 ± 17.09º. The 95th percentile was 66.22º. From sociodemographic data could be extracted that: patients who have children showed a lower GIRD, patients with right shoulder pain, or whose dominance coincided with a painful shoulder showed a higher GIRD. The orthopedic findings revealed that patients with a positive Jobe test showed a lower GIRD. The linear model considering both sociodemographic and orthopedic findings showed that GIRD was reduced by having children and by BMI. GIRD shows a high incidence in patients with shoulder pain. The descendant, BMI, and positive Jobe test were negatively associated with the GIRD.

Treatment of glenohumeral internal rotation deficit in the general population with shoulder pain: An open single-arm clinical trial

BACKGROUND

Maladaptation can provoke important alterations in the arthrokinematics such as an internal rotation reduction in the dominant shoulder compared with the nondominant shoulder known as glenohumeral internal rotation deficit (GIRD). Though the number of studies investigating GIRD in athletic population, there are not studies reporting the efficacy of the GIRD treatment in the nonathlete population, a kind of study required to improve our understanding of patient care with this pathology. This study aimed to describe the efficacy of the GIRD treatment in nonathlete population with shoulder pain.

METHODS

An open single-arm trial with 35 patients was adopted for evaluating the efficacy of GIRD treatment in patients with shoulder pain. All patients with shoulder pain who attended the consultation, accepted, and agreed to participate in the study between October 2020 and March 2021 were included. A treatment sequence including joint manual therapy techniques and soft tissue release techniques was applied in the consultation. Then, patients were instructed to adapt the daily active biological stimulus at home. The IR before (IR0) and after (IR1) the treatment was considered the outcome measure. The GIRD was calculated as the difference between the IR of the non-painful shoulder and the IR of the painful shoulder before (GIRD0) and after treatment (GIRD1). A paired Student t test was used to compare the GIRD of each patient before and after the treatment.

RESULTS

Treatment of the patients significantly increased the IR of the painful shoulder in all the patients (P-value < .0001) So, the mean IR0 was 26.09 ± 14.46º (23.64-28.53), and after the treatment the mean IR1 was 67.98 ± 15.03º (65.48-70.52). The mean difference after the treatment (IR1-IR0) was 41.89 ± 14.74º (39.4-44.39). The treatment also significantly reduced GIRD (P-value < .0001). So, the mean GIRD0 was 42.95 ± 16.26º (40.2-45.7), and after the treatment the mean GIRD1 was -1.05 ± 17.18º (-3.96 to 1.85).

CONCLUSIONS

The treatment administrated in this study significantly increased the internal rotation of the treated and painful shoulder and reduced the GIRD from the first consultation.

LEVEL OF EVIDENCE

Level 3.

Effect of Scapular Fixation on Lateral Movement and Scapular Rotation during Glenohumeral Lateral Distraction Mobilisation

BACKGROUND

Glenohumeral lateral distraction mobilisation (GLDM) is used in patients with shoulder mobility dysfunction. No one has examined the effect of scapular fixation during GLDM. The aim was to measure and compare the lateral movement of the humeral head and the rotational movement of the scapula when three different magnitudes of forces were applied during GLDM, with and without scapular fixation.

METHODS

Seventeen volunteers were recruited (n = 25 shoulders). Three magnitudes of GLDM force (low, medium, and high) were applied under fixation and non-fixation scapular conditions in the open-packed position. Lateral movement of the humeral head was assessed with ultrasound, and a universal goniometer assessed scapular rotation.

RESULTS

The most significant increase in the distance between the coracoid and the humeral head occurred in the scapular fixation condition at all three high-force magnitudes (3.72 mm; p < 0.001). More significant scapular rotation was observed in the non-scapular fixation condition (12.71°). A difference in scapula rotation (10.1°) was observed between scapular fixation and non-scapular fixation during high-force application.

CONCLUSIONS

Scapular fixation resulted in more significant lateral movement of the humeral head than in the non-scapular fixation condition during three intensities of GLDM forces. The scapular position did not change during GLDM with the scapular fixation condition.

Ultrasound findings and prognosis of shoulder pain: A role for Doppler signal?

PURPOSE

To find ultrasound prognostic factors for shoulder pain.

METHODS

This was an observational, prospective study, comparing the evolution of ultrasound findings with clinical outcomes, in patients with shoulder pain. Data were collected in two appointments, from February 2018 to March 2021. Two-tailed non-parametric statistics were used, and p values <0.05 were considered significant.

RESULTS

A total of 79 participants were included in this study (median age 59 years, range 24-70, 61 women). A positive Doppler signal on tendons (p = 0.002) and absent tendon heterogeneity (p = 0.01) were associated with the patient's self-reported improvement. Tendon calcifications with poorly defined contours (p = 0.03) and sparse distribution (p = 0.001) were associated with VAS improvement. A reduction in the number of calcifications (p = 0.004), in the supraspinatus tendon thickness (p = 0.01), in subacromial effusions (p = 0.03), and in color Doppler grade (p = 0.02), between initial and follow-up exams, was found in patients with an improved DASH outcome.

CONCLUSION

A positive Doppler signal on shoulder tendons can be a marker for a better prognosis in shoulder pain. Poorly defined and sparsely distributed calcifications can also indicate a better course of the disease.

Reliability and Validity of Shoulder and Handgrip Strength Testing

Purpose: This study aimed to estimate the intra- and inter-rater reliability of the JTECH computerized, wireless apparatus and its validity (compared to established devices) for measurements of maximal shoulder isometric strength and handgrip strength among healthy adults with no shoulder pathology. Methods: Twenty healthy young adults had shoulder strength tested with JTECH and Micro-FET2 hand-held dynamometers, and the handgrip strength was tested using JTECH and Jamar handgrip dynamometers. Assessments were performed by the same rater to determine intra-rater reliability and convergent validity, at least two days apart, while on a third visit, the other rater performed measures to determine inter-rater reliability. Results: The JTECH computerized, wireless devices demonstrated good to excellent intra-rater reliability (ICCs (2,1) = 0.78-0.97) and inter-rater reliability for strength measures (ICCs (2,1) = 0.76-0.95). The JTECH computerized device compared to the Micro-FET2 hand-held dynamometer showed substantial concurrent validity for shoulder flexion (R2 = 0.87), extension (R2 = 0.87), abduction (R2 = 0.88), and adduction (R2 = 0.85). Substantial concurrent validity was shown for the JTECH computerized device and Jamar handgrip dynamometers (R2 = 0.92). Conclusions: The JTECH computerized, wireless devices demonstrated high intra- and inter-rater reliability and substantial concurrent validity for shoulder isometric strength and handgrip strength in healthy adults.

The relationship between shoulder pain and shoulder disability in women: The mediating role of sleep quality and psychological disorders

The number of patients complaining of shoulder pain is gradually increasing, and women with shoulder pain in particular tend to present with psychological disorders and poor sleep quality. Therefore, the purpose of this study was to investigate whether psychological disorder and poor sleep quality mediated the relationship between shoulder pain and shoulder disability in women. This is a descriptive survey study of 222 women from 3 community centers in Seoul and Gyeonggi-do regions in South Korea. Data about shoulder pain, shoulder disability, sleep quality, depression, anxiety, and stress were collected using structured questionnaires between May 10 and June 7, 2021, and were analyzed by serial mediation analysis. The direct effect of shoulder pain on shoulder disability was statistically significant. Serial mediation model showed that sleep quality and psychological disorders (depression, anxiety, and stress) were sequential mediators between shoulder pain and shoulder disability among women. The relationship between shoulder pain and shoulder disability among women was partially mediated by sleep quality and psychological disorders (depression, anxiety, and stress). The results emphasize the importance of sleep quality and psychological factors in shoulder disability and suggest the use of strategies to improve sleep quality and alleviate psychological factors when developing an intervention program to mitigate shoulder disability in women with shoulder pain.

The morphology of the subacromial and related shoulder bursae. An anatomical and histological study

Shoulder bursae are essential for normal movement and are also implicated in the pathogenesis of shoulder pain and dysfunction. The subacromial bursa (SAB), within the subacromial space, is considered a primary source of shoulder pain. Several other bursae related to the subcoracoid space, including the coracobrachial (CBB), subcoracoid (SCB) and subtendinous bursa of subscapularis (SSB), are also clinically relevant. The detailed morphology and histological characteristics of these bursae are not well described. Sixteen embalmed cadaveric shoulders from eight individuals (five females, three males; mean age 78.6 ± 7.9 years) were investigated using macro-dissection and histological techniques to describe the locations, dimensions and attachments of the bursae, their relationship to surrounding structures and neurovascular supply. Bursal sections were stained with haematoxylin and eosin to examine the synovium and with antibodies against von Willebrand factor and neurofilament to identify blood vessels and neural structures respectively. Four separate bursae were related to the subacromial and subcoracoid spaces. The SAB was large, with a confluent subdeltoid portion in all except one specimen, which displayed a distinct subdeltoid bursa. The SAB roof attached to the lateral edge and deep surface of the acromion and coracoacromial ligament, and the subdeltoid fascia; its floor fused with the supraspinatus tendon and greater tubercle. The CBB (15/16 specimens) was deep to the conjoint tendon of coracobrachialis and short head of biceps brachii and the tip of the coracoid process, while the inconstant SCB (5/16 specimens) was deep to the coracoid process. Located deep to the subscapularis tendon, the SSB was a constant entity that commonly displayed a superior extension. Synovial tissue was predominantly areolar (SAB and SSB) or fibrous (CBB and SCB), with a higher proportion of areolar synovium in the bursal roofs compared to their floors. Blood vessels were consistently present in the subintima with a median density of 3% of the tissue surface area, being greatest in the SSB and SAB roofs (4.9% and 3.4% respectively) and least in the SAB floor (1.8%) and CBB roof and floor (both 1.6%). Nerve bundles and free nerve endings were identified in the subintima in approximately one-third of the samples, while encapsulated nerve endings were present in deeper tissue layers. The extensive expanse and attachments of the SAB support adoption of the term subacromial-subdeltoid bursa. Morphologically, the strong attachments of the bursal roofs and floors along with their free edges manifest as fixed and mobile portions, which enable movement in relation to surrounding structures. The presence of neurovascular structures demonstrates that these bursae potentially contribute blood supply to surrounding structures and are involved in mechanoreception. The anatomical details presented in this study clarify the morphology of the shoulder bursae, including histological findings that offer further insight into their potential function.

Safety and Efficacy of Embolization with Microspheres in Chronic Refractory Inflammatory Shoulder Pain: A Pilot Monocentric Study on 15 Patients

Purpose: Musculoskeletal (MSK) embolization is emerging in tendinopathy treatment. The objective of this study was to assess the efficacy and safety of MSK embolization with microspheres in the treatment of chronic shoulder pain. Patients and methods: This retrospective monocentric study included patients with chronic shoulder pain resistant to 6 months or more of conventional therapies who were treated with MSK embolization between 2017 and 2021. Embolization was performed using calibrated 100–250 µm microspheres. Clinical success was defined as pain reduction, i.e., a decrease in the visual analogue scale (VAS) pain score of ≥50% at 3 months after MSK embolization as compared to baseline. Adverse events were collected. Results: Fifteen patients (11 women, 4 men) were included, with a median age of 50.3 years (IQR: 46.7–54.5). The median duration of symptoms was 26.6 months (20.6–39.8). The median VAS pain scores were 7.0 (7.0–8.0) at baseline, 6.0 (3.5–7.0) at 1 month, 5.0 (4.5–6.5) and 5.0 (3.0–7.4) at 3 months and 6 months (p = 0.002). Three patients (20%) reported clinical success at 3 months. Three patients experienced minor complications after embolization (paresthesia, n = 2; transient osteo-medullary edema, n = 1) and two patients had moderate complications (transient skin ischemia). Conclusion: MSK embolization with microspheres for treatment of refractory chronic shoulder pain showed moderate results in terms of clinical success and safety.

The Effect of Scapular Fixation on Scapular and Humeral Head Movements during Glenohumeral Axial Distraction Mobilization

Background and Objectives: Glenohumeral axial distraction mobilization (GADM) is a usual mobilization technique for patients with shoulder dysfunctions. The effect of scapular fixation on the movement of the scapula and the humeral head during GADM is unknown. To analyze the caudal movement of the humeral head and the rotatory movement of the scapula when applying three different intensities of GADM force with or without scapular fixation. Materials and Methods: Fifteen healthy subjects (mean age 28 ± 9 years; 73.3% male) participated in the study (twenty-eight upper limbs). Low-, medium- and high-force GADM in open-packed position were applied in scapular fixation and non-fixation conditions. The caudal movement of humeral head was evaluated by ultrasound measurements. The scapular rotatory movement was assessed with a universal goniometer. The magnitude of force applied during GADM and the region (glenohumeral joint, shoulder girdle, neck or nowhere) where subjects felt the effect of GADM mobilization were also recorded. Results: A greater caudal movement of the humeral head was observed in the non-scapular fixation condition at the three grades of GADM (p < 0.008). The rotatory movement of the scapula in the scapular fixation condition was practically insignificant (0.05−0.75°). The high-force GADM rotated scapula 18.6° in non-scapular fixation condition. Subjects reported a greater feeling of effect of the techniques in the glenohumeral joint with scapular fixation compared with non-scapular fixation. Conclusions: The caudal movement of the humeral head and the scapular movement were significantly greater in non-scapular fixation condition than in scapular fixation condition for the three magnitudes of GADM force.

Risk factors for shoulder disorders among French workers: prospective cohort study

Objectives

Shoulder disorders are common in the working population. This longitudinal study aimed to explore the relationships between personal factors and occupational organisational, psychosocial, and biomechanical factors and the incidence of shoulder disorders.

Methods

A total of 3710 workers in the Pays de la Loire region (Loire Valley area, France) were randomly included by their occupational physician in the Cosali cohort between 2002 and 2005. All workers completed a self-administered questionnaire about personal factors and work exposure, and using a standardised physical examination, occupational physicians diagnosed shoulder disorders. Between 2007 and 2010, 1611 workers were re-examined by their occupational physician. The 1,320 workers free of shoulder disorders at baseline were studied. A conceptual model was developed in which relationships between organisational, psychosocial, biomechanical, and personal factors at baseline and the incidence of shoulder disorders were assumed. Structural equation modelling was used to test the model.

Results

Shoulder disorders were directly associated with biomechanical factors and age but not with psychosocial factors. However, skill discretion and psychological demand influenced shoulder disorders indirectly through biomechanical factors. Exposure to a work pace dependent on an automatic rate and to a work pace dependent on customers’ demands were associated with biomechanical and psychosocial factors, but not directly to shoulder disorders.

Conclusions

This study identified the complex direct and indirect relationships between occupational factors and shoulder disorders. Our data confirmed our conceptual causation model: organisational and psychosocial factors were associated with biomechanical factors, while biomechanical factors were associated with the incidence of shoulder disorders.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00420-022-01853-9.

Evaluation of Shoulder Microcirculation Abnormality Using Laser Doppler Flowmetry

Severe neck-shoulder pain induces functional limitations in both life and work. The purpose of this study was to determine the characteristics of shoulder microcirculation abnormality in workers. This study recruited 32 workers and patients, both n = 16. Questionnaires were administered, and Laser Doppler Flowmetry (LDF) was used to measure microcirculatory blood flow (MBF) at the myofascial trigger points (MTrPs) on the shoulders. The absolute-deviation_MMBF represented the mean MBF (MMBF) variability among subjects. The differences in the life characteristics, shoulder pain level, and microcirculatory characteristics at MTrPs between the two groups were compared. It was found that shoulder pain level was significantly higher in the patient than in the control group (p < 0.001). Deviation of the MMBF value beyond the postulated “normal range” of 60–80 was significantly higher in the patient than in the control group (p < 0.001). The MMBF deviation was significantly correlated with shoulder pain level, pain duration, and the symptom effect (p < 0.01, n = 32). A normal range for the MMBF of 60–80 on the shoulder near MTrPs is hypothesized for the first time based on this study. Noninvasive LDF can be used to assess abnormality in the MBF on shoulder MTrPs at an early stage.

Ultrasound Features Associated With Shoulder Complaints: Calcifications Larger Than 6 mm in Young Patients and Positive Doppler Are Associated With Pain

Objectives: To identify ultrasound (US) features associated with the presence of shoulder complaints.

Methods: This observational, case-control study, compared US findings between participants with and without shoulder complaints, matched for age, sex, and dominancy. Data was collected from February 2018 to June 2020. Two-tailed Fisher's and Mann-Whitney U-tests were used, with p-values < 0.05 considered significant.

Results: A total of 202 participants were enrolled (median age 56 years, range 18–70, 155 women), comprising 140 cases and 62 controls. A calcification size ≥6 mm, when age < 56 (p = 0.02), and a distance to tendon insertion ≥6 mm, when age ≥56 (p = 0.009), were only found in symptomatic shoulders. Color Doppler in rotator cuff (RC) tendons predominated in the presence of symptoms (26/140 vs. 2/62, p = 0.003). An algorithm also combining the number of calcifications, tendon echotexture and insertional thickening, osseous irregularity, cuff tears, and subacromial effusion showed a 92% (57/62) specificity for shoulder pain on this study sample.

Conclusion: Calcification diameter of 6 mm or more is associated with shoulder pain in patients younger than 56 years. A distance from calcification to tendon insertion of 6 mm or more is related to pain in older patients. Doppler signal also is associated with shoulder pain. An algorithm based on a set of specific ultrasonographic criteria have a strong association with the presence of symptoms.

Cochrane's risk of bias tool for non-randomized studies (ROBINS-I) is frequently misapplied: A methodological systematic review

OBJECTIVES

We aimed to review how 'Risk of Bias In Non-randomized Studies-of Interventions' (ROBINS-I), a Cochrane risk of bias assessment tool, has been used in recent systematic reviews.

STUDY DESIGN AND SETTING

Database and citation searches were conducted in March 2020 to identify recently published reviews using ROBINS-I. Reported ROBINS-I assessments and data on how ROBINS-I was used were extracted from each review. Methodological quality of reviews was assessed using AMSTAR 2 ('A MeaSurement Tool to Assess systematic Reviews').

RESULTS

Of 181 hits, 124 reviews were included. Risk of bias was serious/critical in 54% of assessments on average, most commonly due to confounding. Quality of reviews was mostly low, and modifications and incorrect use of ROBINS-I were common, with 20% reviews modifying the rating scale, 20% understating overall risk of bias, and 19% including critical-risk of bias studies in evidence synthesis. Poorly conducted reviews were more likely to report low/moderate risk of bias (predicted probability 57% [95% CI: 47-67] in critically low-quality reviews, 31% [19-46] in high/moderate-quality reviews).

CONCLUSION

Low-quality reviews frequently apply ROBINS-I incorrectly, and may thus inappropriately include or give too much weight to uncertain evidence. Readers should be aware that such problems can lead to incorrect conclusions in reviews.

Scapular Retraction under Adduction Load: An Alternative to Overhead Exercises to Activate Infraspinatus, Upper, and Lower Trapezius in Subjects with and without Shoulder Pain

Exercises for lower trapezius (LT) often use overhead positions, causing compressive forces to the subacromial space. Scapular retraction would be an alternative to activate LT muscle. The present study aimed to assess the excitation levels of infraspinatus, upper trapezius, and lower trapezius muscles during a scapular retraction exercise under progressive adduction loads in subjects with and without painful shoulder. Electromyography of infraspinatus (IS), upper trapezius (UT), and LT was recorded during scapular retraction under progressive adduction loads of 42 participants, divided into two groups: with (SP, n = 26) and without shoulder pain (nSP, n = 16). The adduction loads of 20%, 30%, 40%, and 50% of the maximal voluntary contraction (MVC) were applied using a load cell. Normalized electromyography and the ratio between UT and LT (UT:LT) were used for statistical analysis. No differences were observed between groups, but a condition effect occurred for all muscles: UT showed higher values at 50% vs. 20% of MVC (p = 0.004); LT showed higher values on 40% and 50% of MVC (p = 0.001; 0.006). Higher values for IS were noted at 40% of MVC (vs. 20% of MVC; p = 0.04) and at 50% of MVC (vs. 20% of MVC; p = 0.001, vs. 30% of MVC, p = 0.001; vs. 40% of MVC; p = 0.001). UT:LT showed lower values at 50% of MVC (vs. 20% of MVC; p = 0.001 and vs. 30% of MVC; p = 0.016). Scapular retraction with adduction loads at 40-50% is an alternative to overhead exercises aiming to activate the LT and the IS muscles. The exercise ensures higher levels of LT and IS excitation without increasing UT excitation.

Predicting change in symptoms and function in patients with persistent shoulder pain: a prognostic model development study

BACKGROUND

Persistent shoulder pain causes considerable disruption of the individual's life and imposes high costs on healthcare and society. Well-informed treatment and referral pathways are crucial as unsuccessful interventions and longer duration of symptoms minimizes the likelihood of success in future interventions. Although physiotherapy is generally recommended as first line treatment, no prognostic model or clinical prediction rules exists to help guide the treatment of patients with persistent shoulder pain undergoing physiotherapy. Thus, the objective of this study was to develop a prognostic model to inform clinical decision making and predict change in symptoms and function in patients with persistent shoulder pain.

METHODS

This was a prospective cohort study of 243 patients with persistent shoulder pain referred to outpatient physiotherapy rehabilitation centres. Data was collected at baseline and six-month follow-up. The outcome was change in shoulder symptoms and function as measured by the shortened version of the Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH) from baseline to 6 months follow up. Potential predictors were included in a multivariable linear regression model which was pruned using modified stepwise backwards elimination.

RESULTS

The final model consisted of seven predictors; baseline QuickDASH score, employment status, educational level, movement impairment classification, self-rated ability to cope with the pain, health-related quality of life and pain catastrophizing. Together these variables explained 33% of the variance in QuickDASH-change scores with a model root mean squared error of 17 points.

CONCLUSION

The final prediction model explained 33% of the variance in QuickDASH change-scores at 6 months. The root mean squared error (model SD) was relatively large meaning that the prediction of individual change scores was quite imprecise. Thus, the clinical utility of the prediction model is limited in its current form. Further work needs be done in order to improve the performance and precision of the model before external validity can be examined along with the potential impact of the model in clinical practice. Two of the included predictors were novel and could be examined in future studies; movement impairment classification based on diagnosis and health-related quality of life.

Rehabilitation of An Analgesic Bracelet Based on Wrist-Ankle Acupuncture in Patients with Rotator Cuff Injury: A Randomized Trial

Objective

To evaluate the effect of transcutaneous electrical nerve stimulation (C-TENS) in the rehabilitation of rotator cuff injury.

Methods

A total of 60 patients diagnosed with mild to moderate rotator cuff injury were randomly divided into the control group and test group. Both groups received conventional rehabilitation treatment including physical therapy, joint mobilization, interventional therapy, and family recovery training. The test group additionally received TENS treatment on the upper area 4 or 5 of the wrist, based on the wrist-ankle acupuncture (WAA) theory. The results of the visual analogue scale (VAS), shoulder range of motion (ROM), and Constant-Murley score (CMs) were collected before and after the 1^st treatment and after the 5^th treatment. The differences of those indicators between the two groups were analyzed statistically.

Results

The VAS scores of measurement points after treatment were all improved compared with those at baseline. There was a significant difference between the two groups after the 1^st and the 5^th treatment (p < 0.05), and the improvements in the test group were better than those in the control group. The ROM of flexion, extension, abduction, adduction, internal rotation, and external rotation after the 1^st treatment and 5^th treatment in both groups were all improved compared with those at baseline. There was no significant difference between two groups. The CMs of the two groups after the 5^th treatment were all improved compared with those at baseline. There was no significant difference between two groups. No adverse events occurred during the treatment.

Conclusion

Electrical stimulation on the wrist combined with conventional rehabilitation is more effective in relieving pain than the conventional rehabilitation alone. Electrical stimulation on the wrist combined with conventional rehabilitation has no obvious effect in improving shoulder joint mobility and shoulder function.

Clinical evaluation of somatosensory integrity in people with chronic shoulder pain

PURPOSE

Indirect evaluation tests of somatosensory integrity, such as the left/right judgment task and two-point discrimination thresholds, are used to complement a clinical evaluation facilitating tailored rehabilitation programs for patients with chronic pain. This study aimed to compare performance on the left/right judgment task and two-point shoulder discrimination thresholds between people with chronic shoulder pain and asymptomatic controls. The study's secondary objective was to investigate whether there is a relationship between pain intensity and the painful area with TPDT and LRJT.

MATERIALS AND METHODS

It is a cross-sectional study with a control group. Volunteers participated in the left/right judgment task using the Recognise Shoulder^TM app, and two-point discrimination thresholds were performed using a Mitutoyo® digital caliper. The extent of the painful area, affectivity, and functionality were also determined to characterize the sample.

RESULTS

We assessed 52 symptomatic and 50 asymptomatic individuals. A between-group difference was observed in time response for the left/right judgment task (p = 0.025) and the two-point discrimination thresholds when tested over the shoulder's lateral region (p = 0.012). There was a significant positive weak correlation between pain intensity and TPDT test performance over the anterior shoulder (rs = 0.35; p = 0.01) and a positive weak correlation between pain area and LRJT response time (rs = 0.26; p = 0.04).

CONCLUSIONS

This study demonstrates a difference of small magnitude in the response time of the LRJT for the shoulder segment and TPDT in the lateral shoulder region between individuals with chronic shoulder pain and asymptomatic controls.

Sarcopenia Is Associated With Increased Risks of Rotator Cuff Tendon Diseases Among Community-Dwelling Elders: A Cross-Sectional Quantitative Ultrasound Study

Backgrounds: Recently, the association between sarcopenia and various musculoskeletal disorders, such as lumbar spine stenosis and fibromyalgia, has been highlighted. However, the relationship between sarcopenia and rotator cuff tendon diseases has rarely been investigated. This study aimed to evaluate whether sarcopenia was associated with shoulder pain and to determine whether rotator cuff tendons differed in echotexture between the sarcopenic and non-sarcopenic populations.

Methods: The thickness and echogenicity ratio of the tendon vs. the overlying muscle (ER_TM) or subcutaneous tissue (ER_TT) were measured using high-resolution ultrasonography in 56 sarcopenic patients and 56 sex- and age- matched controls. The association between ultrasound measurements of the rotator cuff tendon complex and sarcopenia was investigated using the generalized estimating equation (GEE).

Results: The sarcopenic group had an increased prevalence of shoulder pain. Based on the GEE analysis, sarcopenia was significantly associated with an increase in supraspinatus tendon thickness (β coefficient = 0.447, p < 0.001) and a decrease in the ER_TM for the biceps long head and rotator cuff tendons. A negative trend of association was observed between sarcopenia and ER_TT in the supraspinatus tendons (β coefficient = −0.097, p = 0.070). Nevertheless, sarcopenia was not associated with an increased risk of rotator cuff tendon tears.

Conclusions: Patients with sarcopenia have a higher risk of shoulder pain. A consistent tendinopathic change develops in the supraspinatus tendons in sarcopenic patients. However, sarcopenia is less likely to be associated with serious rotator cuff pathology, such as tendon tears. Prospective cohort studies are warranted to explore the causal relationship between sarcopenia and shoulder disorders.

The Addition of Real-time Ultrasound Visual Feedback to Manual Facilitation Increases Serratus Anterior Activation in Adults With Painful Shoulders: A Randomized Crossover Trial

OBJECTIVE

Serratus anterior (SA) muscle activation may be decreased with subacromial pain syndrome. The purpose of this study was to determine whether the addition of real-time ultrasound (RTUS) visual feedback increased activation of SA in adults with painful shoulders in comparison to manual facilitation alone.

METHODS

This assessor-blinded, 2-period, randomized cross-over trial was conducted in a university medical imaging laboratory. Adults with mild-moderate unilateral subacromial pain received both interventions in random order with at least 1-week washout between interventions. Fourteen participants were randomized to receive manual facilitation with RTUS first, and 13 were randomized to receive manual facilitation alone first. Fifteen repetitions of a supine ``serratus punch'' were facilitated by RTUS visual feedback with manual facilitation or by manual facilitation alone. Levels of SA activation via surface electromyography were normalized to a maximum voluntary isometric contraction.

RESULTS

A total of 25 participants completed the full trial of both interventions. Data from 25 participant periods for RTUS with manual facilitation and data from 26 participant periods for manual facilitation only were analyzed. The predicted marginal mean difference between interventions was 55.5% (95% CI = 13.9% to 97.1%) in favor of the addition of RTUS feedback. No adverse effects occurred.

CONCLUSION

RTUS visual feedback increases SA activation in adults with painful shoulders compared with manual facilitation alone.

IMPACT

Determining if RTUS can improve SA muscle activation may help clinicians improve physical therapist interventions for subacromial pain syndrome.

Shoulder pain among male industrial workers: Validation of a conceptual model in two independent French working populations

This study aims to validate a conceptual model for shoulder pain risk factors in two independent samples of male industrial workers: the Cosali cohort (n = 334) and one pharmaceutical company (n = 487). Direct and indirect relationships between work organization factors (automatic speed of a machine or movement of a product and work pace dependent on customers' demand), psychosocial factors (Job strain model), biomechanical factors (working with abducted arms, working with arms at or above shoulder level, and perceived physical exertion), perceived stress, and shoulder pain were explored using structural equation models. Shoulder pain was positively associated with biomechanical exposure in both samples, and with perceived stress only in the pharmaceutical preparation manufacturer, while factors related to work organization and psychosocial factors had indirect impacts on the risk of chronic shoulder pain in both samples. The results provide a deeper understanding of the complex relationships between workplace risk factors and shoulder pain.