Reliability of Hip Strength Assessment in Young Active People with Hip Dysplasia: An Examination in Student Circus Artists.

BACKGROUND: Developmental dysplasia of the hip (DDH) is common in performing artists and other young active individuals and involves abnormalities in bony morphology of the acetabulum and proximal femur that can negatively impact walking biomechanics, muscular strength, quality of life, and sleep. Rehabilitation for hip-related conditions should target known modifiable impairments such as hip muscle strength, though a reliable method of assessment in this population remains unclear. OBJECTIVE: To determine the inter- and intra-rater reliability of hip muscle strength assessments using handheld dynamometry (HHD) in young active circus artists with DDH. METHODS: Reliability of hip strength in all planes was assessed using HHD in 21 adult performing circus arts students (mean age 21.3 yrs [3.2]; 13 M, 5 F, 3 NB) with symptomatic radiologically and clinically diagnosed hip dysplasia. The reliability of average peak force and absolute peak force were expressed for each position tested. Reliability was assessed using intraclass correlation coefficients (ICC) with standard error of measurement (SEM) and minimal detectable change (MDC) values calculated to improve clinical interpretability. RESULTS: Good to excellent inter-rater reliability resulted for all hip muscle strength testing positions, ICC=0.88 (95%CI 0.70 to 0.95) to ICC=0.97 (0.92 to 0.99), except average peak hip flexion strength, ICC=0.71 (0.28 to 0.88). Absolute peak hip abduction, ICC=0.77 (0.16 to 0.94), and adduction strength, ICC=0.72 (-0.55 to 0.92), demonstrated the lowest intra-rater reliability. Transverse plane strength measures (rotation) produced the lowest SEM and MDC values followed by the frontal plane (abduction/adduction) and sagittal plane (flexion/extension). CONCLUSION: HHD is an appropriate and reliable method to assess hip muscle strength in circus artists with DDH.

Getting more from standard rotator cuff strengthening exercises.

BACKGROUND: A simple modification to standard rotator cuff exercises using an additional resistance band around the scapula has been recommended in the clinical setting, postulated to encourage activation of the posterior scapular stabilisers and increase rotator cuff activation. The aim of this clinical laboratory study was to compare scapular and rotator cuff muscle activation between standard and modified exercises. METHODS: Electromyographic data were collected from 10 healthy adults via surface and intramuscular electrodes from the scapular and rotator cuff muscles. Internal and external rotation exercises of the shoulder with the arm abducted to 0°, 45° and 90° were performed using one handheld resistance band (standard) or two bands with the additional band applied to the scapula (modified). RESULTS: Activation of the trapezii and rhomboid muscles during the modified exercises at 0° and 45° of abduction was significantly greater when compared to the standard exercises (P < 0.05). No significant differences were found in rotator cuff muscle activation. DISCUSSION: Applying resistance to the posterior scapula increases activation of some scapular stabilising muscles particularly in lower ranges of abduction. This study provides preliminary evidence that this simple modification can elicit greater scapular muscle activity, potentially producing enhanced exercise outcomes with minimal additional effort.

The effect of female sex hormone supplementation on tendon in pre and postmenopausal women: A systematic review.

OBJECTIVES: Oestrogen deprivation has been shown to have a negative effect on connective tissue and its turnover. A link may exist between supplemental oestrogen, preservation of tendon collagen and less tendon abnormality. The aim was to determine the effects of female sex hormone supplementation (FSHS) on tendon. METHODS: A systematic search of nine key health databases; Medline, CINAHL, EMBASE, SPORTDiscus, AUSPORT and AMI, Cochrane Library, SafetyLit and PEDro was completed (to Feb 24, 2016). The search yielded 6378 records using terms relating to hormone (oestrogen, estrogen, hormone replacement therapy, HRT, estrogen therapy, oestrogen therapy, oral contraceptive pill) and tendon. Quality assessment, data extraction and data synthesis of included papers was undertaken. RESULTS: Low level of evidence for all outcomes; no positive or negative link between FSHS and molecular, mechanical and morphological tendon response outcomes, and the addition of exercise to FSHS, had minimal effects on tendon CSA. CONCLUSIONS: The effect of oestrogen supplementation on tendon is contradictory and inconsistent. This review suggests there is a need for further studies to understand the effects of FSHS on tendon tissue at a mechanical, morphological and molecular level.

Development and validation of a VISA tendinopathy questionnaire for greater trochanteric pain syndrome, the VISA-G.

BACKGROUND: Greater trochanteric pain syndrome (GTPS) is common, resulting in significant pain and disability. There is no condition specific outcome score to evaluate the degree of severity of disability associated with GTPS in patients with this condition. OBJECTIVE: To develop a reliable and valid outcome measurement capable of evaluating the severity of disability associated with GTPS. METHODS: A phenomenological framework using in-depth semi structured interviews of patients and medical experts, and focus groups of physiotherapists was used in the item generation. Item and format clarification was undertaken via piloting. Multivariate analysis provided the basis for item reduction. The resultant VISA-G was tested for reliability with the inter class co-efficient (ICC), internal consistency (Cronbach's Alpha), and construct validity (correlation co-efficient) on 52 naïve participants with GTPS and 31 asymptomatic participants. RESULTS: The resultant outcome measurement tool is consistent in style with existing tendinopathy outcome measurement tools, namely the suite of VISA scores. The VISA-G was found to be have a test-retest reliability of ICC2,1 (95% CI) of 0.827 (0.638-0.923). Internal consistency was high with a Cronbach's Alpha of 0.809. Construct validity was demonstrated: the VISA-G measures different constructs than tools previously used in assessing GTPS, the Harris Hip Score and the Oswestry Disability Index (Spearman Rho:0.020 and 0.0205 respectively). The VISA-G did not demonstrate any floor or ceiling effect in symptomatic participants. CONCLUSION: The VISA-G is a reliable and valid score for measuring the severity of disability associated GTPS.