The supine moving apprehension test-Reliability and validity among healthy individuals and patients with anterior shoulder instability.

Background: Performance-based tests for patients with anterior shoulder dislocation are lacking. This study determined the reliability and validity of the supine moving apprehension test designed to assess the ability to control anterior instability loads. Methods: Thirty-six participants were recruited (18 healthy individuals, and 18 patients following anterior shoulder dislocation). Healthy participants performed the supine moving apprehension test on 2 separate occasions to determine test-retest reliability. Patients completed the supine moving apprehension test and the Western Ontario Shoulder Instability index before and 6 months after surgical stabilization of their shoulder. The presence of anterior apprehension was also documented post-operatively. Results: The supine moving apprehension test demonstrated good test-retest reliability (intraclass correlation coefficient = 0.74-0.84). Patients performed 18-30 repetitions less than healthy individuals during the supine moving apprehension test (P < 0.01). A strong correlation was found between supine moving apprehension test scores and Western Ontario Shoulder Instability post-operatively (r = -0.74, P ≤ 0.01). Supine moving apprehension test scores significantly improved among patients following surgery (P < 0.01). Patients with a negative apprehension test post-operatively performed the supine moving apprehension test significantly better than patients with a positive apprehension test (P < 0.01). Conclusions: The supine moving apprehension test is reliable and valid among patients with anterior shoulder dislocation and may serve to assess patients' ability to control shoulder anterior instability loads.

Reliability and validity of the K-force grip dynamometer in healthy subjects: do we need to assess it three times?

Introduction: Digital dynamometers to assess grip strength are becoming more common in research and clinical settings. The aim of the study was to assess validity and reliability of the K-force dynamometer compared to the Jamar dynamometer. We also aimed to assess differences over the course of three measurements. Methods: Twenty-seven healthy participants were included. Three trials with the K-force and Jamar dynamometers were completed. Testing order was randomised. Intraclass correlation coefficients (ICCs) with absolute agreement assessed reliability and validity. Standard error of the measurement (SEM) and minimal detectable change (MDC95) were calculated. Concurrent validity was assessed using Pearson's correlations and ICCs. Differences between the three repetitions were assessed using one-way repeated measures ANOVAs. Results: Both the K-force and the Jamar presented excellent intra-rater reliability with ICCs ranging from 0.96 to 0.97. The SEM ranged from 1.7 to 2 kg and the MDC from 4.7 to 5.7 kg for both dynamometers. The concurrent validity of the K-force was high (r ≥ 0.89). However, the K-force underestimated the grip strength by 4.5-8.5 kg. There was no change in grip strength with either dynamometer over the course of three trials. Conclusions: The K-force is reliable, but it underestimates grip strength by 4.5-8.5 kg compared to the Jamar dynamometer. K-force can be used to monitor progress over time but cannot be used to compare results against normative data. The use of a single measurement when assessing grip strength is sufficient when assessing healthy subjects.

Validity and Reliability of the Kinvent Handheld Dynamometer in the Athletic Shoulder Test.

CONTEXT: Long-lever shoulder strength tests may aid clinical decision-making regarding return to sport after a shoulder injury. The Athletic Shoulder Test (AST) was developed to measure force production in 3 positions of shoulder abduction (90°, 135°, and 180°) using force plates. However, handheld dynamometers (HHDs) are more portable, affordable, and may provide valid and reliable results which would increase the clinical utility of long-lever tests. HHDs vary in shape, design, and their capacity to report parameters such as rate of force production and require further investigation. The aim of this study was to examine the intrarater reliability of the Kinvent HHD and assess its validity against Kinvent force plates in the AST. Peak force (in kilograms), torque (in Newton meters), and normalized torque (in Newton meters per kilogram) were reported. DESIGN: Validity and reliability study. METHODS: Twenty-seven participants with no history of upper limb injury performed the test in a randomized order using the Kinvent HHD and force plates. Each condition was assessed 3 times, and peak force was recorded. Arm length was measured to calculate peak torque. Normalized peak torque was calculated by dividing torque by bodyweight (in kilograms). RESULTS: The Kinvent HHD is reliable when measuring force (intraclass correlation coefficient [ICC] ≥ .80), torque (ICC ≥ .84), and normalized torque (ICC ≥ .64) during the AST. The Kinvent HHD is also valid when compared with the Kinvent force plates for force (ICC ≥ .79; r ≥ .82), torque (ICC ≥ .82; r ≥ .76), and normalized torque (ICC ≥ .71; r ≥ .61). There were no statistically significant differences across the 3 trials on analyses of variance (P > .05). CONCLUSIONS: The Kinvent HHD is a reliable tool when used to measure force, torque, and normalized torque in the AST. Furthermore, given the lack of significant difference between trials, clinicians can use one test to accurately report relative peak force/torque/normalized torque rather than average 3 separate trials. Finally, the Kinvent HHD is valid when compared with Kinvent force plates.

Depression, fear of re-injury and kinesiophobia resulted in worse pain, quality of life, function and level of return to sport in patients with shoulder instability: a systematic review.

INTRODUCTION: Maladaptive psychological responses may hinder participation and return to pre-injury level in sport. The aim of this study was to investigate the psychological factors influence on pain, function, quality of life and time to return to sport in subjects with shoulder instability. EVIDENCE ACQUISITION: The research was conducted until the 15th of May 2022 in MEDLINE, CENTRAL, PEDro, and PubPSYCH regardless language, publication status or date. We included adults (≥16 years old) with shoulder instability. Quality assessment was performed using Joanna Briggs Institute Critical Appraisal tools. EVIDENCE SYNTHESIS: Three papers, 270 participants, met the inclusion criteria. Subjects with preoperative depression demonstrated worse 1-year postoperative shoulder-related quality of life score than the cohort without depression. Shoulder function had a weak negative correlation with depression. Pain intensity and depression showed a positive correlation of moderate strength. Fear of re-injury correlated with SPADI total, pain and function; moreover, it increased the likelihood of recurrent dislocation in multivariate analysis. Kinesiophobia at baseline correlated with WOSI. CONCLUSIONS: Depression, fear of re-injury and kinesiophobia correlate with pain, function, quality of life and return to sport in people with shoulder instability. We recommend a multi-professional approach to integrate the psychological standpoint in rehabilitation treatment to maximize quality of life and function in subjects with instability.

Factor Structure of the Shoulder Instability Return to Sport After Injury Scale: Performance Confidence, Reinjury Fear and Risk, Emotions, Rehabilitation and Surgery.

BACKGROUND: Rates of return to play after shoulder dislocation vary between 48% and 96%, and there has been scant attention given to the psychosocial factors that influence return to play after a shoulder injury. PURPOSE: To establish the factor structure of the Shoulder Return to Sport after Injury (SI-RSI) scale and examine how the SI-RSI is associated with the Western Ontario Shoulder Instability Index (WOSI). STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: The SI-RSI is designed to measure psychological readiness to return to play after shoulder dislocation and was administered to participants who had at least 1 episode of shoulder dislocation and were planning or had returned to sports. The WOSI was also completed by the participants, and descriptive data were gathered. Reliability (Cronbach α) and factor analysis of the SI-RSI were undertaken. Correlations between the SI-RSI and WOSI were made, and differences between various patient subgroups (first-time dislocations vs multiple episodes of instability, surgery vs no surgery, return to sports vs no return) were analyzed. RESULTS: The SI-RSI had high internal consistency (Cronbach α = 0.84) and was shown to have 4 distinct factors that represented the following constructs: performance confidence, reinjury fear and risk, emotions, and rehabilitation and surgery. Moderate correlations were seen between SI-RSI and WOSI scores. Participants who had undergone surgery scored significantly lower on the reinjury fear and risk subscale of the SI-RSI (P = .04). Those who had sustained multiple dislocations were significantly more concerned about having to undergo rehabilitation and surgery again (P = .007). Participants who had returned to sports had significantly greater fear and thought they were more at risk of reinjury (P = .02). CONCLUSION: Athletes return to sports after a shoulder dislocation despite reporting high levels of fear and concern for their shoulder. High levels of fear and concern may underpin why rates of recurrent shoulder instability are so high. Four distinct elements of psychological readiness appeared to be present in this patient group.

Line Hops and Side Hold Rotation Tests Load Both Anterior and Posterior Shoulder: A Biomechanical Study.

BACKGROUND: Clinical tests should replicate the stressful positions encountered during sport participation. Evaluating the kinetic and electromyographical demands of clinical tests enables clinicians to choose appropriate tests for specific sports. PURPOSE: To describe the shoulder forces and muscle activation levels during closed chain functional tests of Line Hops (LH) and Side Hold Rotation (SHR). STUDY DESIGN: Descriptive biomechanical study. METHODS: Ten asymptomatic participants were examined in a university laboratory. Two functional tests were evaluated using three-dimensional video analysis and electromyography to measure shoulder forces, moments, and muscular activity levels. RESULTS: SHR produced a peak average posterior translation force of 4.84 N/kg (CI95 4.32-5.36N/kg) and a peak average anterior translational force of 1.57 N/kg (CI95 1.10-2.01N/kg). High levels of serratus anterior (98% maximum voluntary isometric contraction (MVIC) and infraspinatus (52 %MVIC) were recorded during SHR. LH produced a posterior translational force of 4.25 N/kg (CI95 3.44-5.06N/kg). High levels of serratus anterior (105 %MVIC) and infraspinatus (87 %MVIC) were recorded during the push off phase of this activity. CONCLUSIONS: LH and SHR placed large posterior translational forces that approached half of a person's bodyweight on shoulder structures. SHR produced an anterior translation force at extremes of horizontal abduction placing approximately 18% of bodyweight on shoulder structures. The LH test required the serratus anterior to provide power to push the upper torso of the ground while both the serratus and the infraspinatus provides scapular and humeral stability, respectively. LEVEL OF EVIDENCE: 4: Case series.

Predicting Recurrent Instability of the Shoulder (PRIS): A Valid Tool to Predict Which Patients Will Not Have Repeat Shoulder Instability After First-Time Traumatic Anterior Dislocation.

OBJECTIVE: To assess the sensitivity, specificity, and validity of the Predicting Recurrent Instability of the Shoulder (PRIS) tool in people with a first-time traumatic anterior shoulder dislocation. DESIGN: Prospective cohort study. METHODS: People with first-time traumatic anterior shoulder dislocation (n = 85), aged 16 to 40 years, were recruited within 12 weeks of their shoulder dislocation and followed prospectively for 1 year post injury. We calculated the sensitivity, specificity, negative predictive value, and positive predictive value of the PRIS tool. RESULTS: Of the 75 participants available for 1-year follow-up, 57 (76%) did not have recurrent shoulder instability. With the PRIS tool cut point set at 0.895, the tool's sensitivity was 39% (95% confidence interval [CI]: 17.3%, 64.3%) and its specificity was 95% (95% CI: 85.4%, 98.9%). The area under the curve was 0.69 (95% CI: 0.55, 0.84; P = .01). The PRIS tool correctly identified 54 of the 57 (95%) who did not have recurrent instability (accuracy, 81%; 95% CI: 70.7%, 89.4%). Negative and positive predictive values were 83% (95% CI: 77.2%, 87.7%) and 70% (95% CI: 40.2%, 89.0%), respectively. CONCLUSION: The PRIS tool can predict those who will not have further shoulder instability in the year following first-time traumatic anterior shoulder dislocation. The PRIS tool cannot accurately predict those who will have recurrent shoulder instability. J Orthop Sports Phys Ther 2020;50(8):431-437. doi:10.2519/jospt.2020.9284.

Normative Rugby Data of the SARTS Tests: Comparison of Elite and School Players.

This study aimed to examine the normative data for the SARTS rugby tests in elite and schoolboy rugby players. A second aim was to examine differences between level of sport and position of play in the SARTS rugby tests. Elite (N = 57) and Schoolboy (N = 63) rugby players performed the SARTS tests relevant to rugby players each for 1 min, with 1-2 min rest between each test. A 2×2 factorial ANOVA was used to assess for the main effect of player position and player level of play. Results showed that elite players performed more Ball Abduction External Rotation (BABER) (dominant and non-dominant), Side Hold Rotations (dominant and non-dominant), Ball Taps (dominant and non-dominant), and Overhead Snatch than schoolboy players. Heavier players performed fewer Push-up Claps. Injured rugby players should perform at least the mean value of the repetitions of the SARTS tests before returning to contact training after an injury.

Reliability of a shoulder arm return to sport test battery.

OBJECTIVES: To establish the reliability and responsiveness of a clinical test battery developed to determine readiness to return to sport after an upper extremity injury. A second objective was to examine the limb symmetry in single limb tests. DESIGN: Methodological study. PARTICIPANTS: Forty healthy participants (20 male) were tested weekly on three occasions. MAIN OUTCOME MEASURES: Learning effect, inter-rater and intra-rater reliability was calculated for each test in the Shoulder Arm Return to Sports (SARTS) battery with repeated measures ANOVA and intraclass correlation coefficient (ICC). Measurement error and responsiveness were determined using Standard Error of Measure (SEM) and Minimal Detectable Change (MDC). RESULTS: Drop Catches and Ball Taps showed a learning effect between Days 2-3. Intra-rater reliability for the remaining six tests between Days 2-3 ranged between 0.78 (95%CI 0.63-0.88) and 0.96 (95%CI 0.92-0.98) while inter-rater reliability on Day 2 ranged between ICC = 0.96 (95%CI 0.94-0.98) and ICC = 0.99 (95%CI 0.98-0.98). Two tests (BABER (91%) and Drop Catches (93%)) were significantly decreased on the non-dominant side (p = 0.05). CONCLUSIONS: Six of the eight tests in the SARTS test battery demonstrate good psychometric properties to evaluate both open and closed chain upper extremity activities indicating their readiness for clinical use.

Who will redislocate his/her shoulder? Predicting recurrent instability following a first traumatic anterior shoulder dislocation.

OBJECTIVE: To develop a multivariate tool that would predict recurrent instability after a first-time traumatic anterior shoulder dislocation. METHODS: Participants (aged 16-40 years) were recruited across New Zealand into a prospective cohort study. Baseline data were collected during a telephone interview and through examination of radiology records. Variables associated with recurrent instability were selected for the multivariate logistic regression model using backwards selection (p<0.10). Coefficients for those variables retained in the model were used to develop the predictive tool. RESULTS: Among the 128 participants, 36% had redislocated at least once in the first 12 months. Univariate analysis showed an increased likelihood of recurrent dislocation with bony Bankart lesions (OR=3.65, 95% CI 1.05 to 12.70, p=0.04) and participants who had: not been immobilised in a sling (OR = 0.38, 95% CI 0.15 to 0.98, p=0.05), higher levels of shoulder activity (OR=1.13, 95% CI 1.01 to 1.27, p=0.03), higher levels of pain and disability (OR=1.03, 95% CI 1.01 to 1.06, p=0.02), higher levels of fear of reinjury (OR=1.12, 95% CI 1.01 to 1.26, p=0.04) and decreased quality of life (OR=1.01, 95% CI 1.00 to 1.02, p=0.05). There was no significant difference in those with non-dominant compared with dominant shoulder dislocations (p=0.10) or in those aged 16-25 years compared with 26-40 years (p=0.07). CONCLUSION: Six of seven physical and psychosocial factors can be used to predict recurrent shoulder instability following a first-time traumatic anterior shoulder dislocation.

Biomechanical properties of the plantar flexor muscle-tendon complex 6 months post-rupture of the Achilles tendon.

We compared the effects of a non-weight bearing protocol (NWB) and a weight bearing (WB) protocol on energy stored, stiffness, and shock absorption in the plantar flexor muscle-tendon unit of patients managed non-operatively following an Achilles tendon rupture. Thirty-eight subjects were randomized to a WB cast fitted with a Bohler iron or a traditional non-weight-bearing cast. At a 6-month follow-up, a biomechanical assessment utilizing an isokinetic dynamometer allowed measurement of peak passive torque, energy stored, shock absorption, and stiffness. The WB group had greater peak passive torque (≈ 20%). Irrespective of group, peak passive torque in unaffected legs was greater (≈ 26%) than affected legs. Across the groups, energy stored in the NWB group was 74% of the WB group. The energy stored in affected legs was 80% of that in unaffected legs. Shock absorption was not significantly different across legs or groups. Irrespective of group, affected legs had significantly less stiffness (20-40%). While the augmentation of plaster with a Bohler iron to allow increased weight bearing had positive effects, deficits in affected compared to unaffected legs irrespective of group were notable, and should be addressed prior to participation in vigorous physical activities.

Active stiffness and strength in people with unilateral anterior shoulder instability: a bilateral comparison.

CONTEXT: Active muscle stiffness might protect the unstable shoulder from recurrent dislocation. OBJECTIVE: To compare strength and active stiffness in participants with unilateral anterior shoulder instability and to examine the relationship between active stiffness and functional ability. DESIGN: Cross-sectional study. SETTING: University research laboratory. PATIENTS OR OTHER PARTICIPANTS: Participants included 16 males (age range, 16-40 years; height = 179.4 ± 6.1 cm; mass = 79.1 ± 6.8 kg) with 2 or more episodes of unilateral traumatic anterior shoulder instability. MAIN OUTCOME MEASURE(S): Active stiffness and maximal voluntary strength were measured bilaterally in participants. In addition, quality of life, function, and perceived instability were measured using the Western Ontario Stability Index, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, and Single Alpha Numeric Evaluation, respectively. RESULTS: We found less horizontal adduction strength (t(15) = -4.092, P = .001) and less stiffness at 30% (t(14) = -3.796, P = .002) and 50% (t(12) = -2.341, P = .04) maximal voluntary strength in the unstable than stable shoulder. Active stiffness was not correlated with quality of life, function, or perceived instability (r range, 0.0-0.25; P > .05). CONCLUSIONS: The observed reduction in stiffness in the unstable shoulder warrants inclusion of exercises in the rehabilitation program to protect the joint from perturbations that might lead to dislocation. The lack of association between active stiffness and quality of life, function, or perceived instability might indicate that stiffness plays a less direct role in shoulder stability.