Sian Williams

Effect of External Ankle Support on Ankle and Knee Biomechanics During the Cutting Maneuver in Basketball Players

Background: Despite the high prevalence of lower extremity injuries in female basketball players as well as a high proportion of athletes who wear ankle braces, there is a paucity of research pertaining to the effects of ankle bracing on ankle and knee biomechanics during basketball-specific tasks. Purpose: To compare the effects of a lace-up brace (ASO), a hinged brace (Active T2), and no ankle bracing (control) on ankle and knee joint kinematics and joint reaction forces in female basketball athletes during a cutting maneuver. Study Design: Controlled laboratory study. Methods: Twenty healthy, semi-elite female basketball players performed a cutting task under both ankle brace conditions (lace-up ankle brace and hinged ankle brace) and a no-brace condition. The 3-dimensional kinematics of the ankle and knee during the cutting maneuver were measured with an 18-camera motion analysis system (250 Hz), and ground-reaction force data were collected by use of a multichannel force plate (2000 Hz) to quantify ankle and knee joint reaction forces. Conditions were randomized using a block randomization method. Results: Compared with the control condition, the hinged ankle brace significantly restricted peak ankle inversion (mean difference, 1.7°; P = .023). No significant difference was found between the lace-up brace and the control condition (P = .865). Compared with the lace-up brace, the hinged brace significantly reduced ankle and knee joint compressive forces at the time of peak ankle dorsiflexion (mean difference, 1.5 N/kg [P = .018] and 1.4 N/kg [P = .013], respectively). Additionally, the hinged ankle brace significantly reduced knee anterior shear forces compared with the lace-up brace both during the deceleration phase and at peak ankle dorsiflexion (mean difference, 0.8 N/kg [P = .018] and 0.9 N/kg [P = .011], respectively). Conclusion: The hinged ankle brace significantly reduced ankle inversion compared with the no-brace condition and reduced ankle and knee joint forces compared with the lace-up brace in a female basketball population during a cutting task. Compared with the lace-up brace, the hinged brace may be a better choice of prophylactic ankle support for female basketball players from a biomechanical perspective. However, both braces increased knee internal rotation and knee abduction angles, which may be problematic for a population that already has a high prevalence of knee injuries.

Predicting 1 Repetition Maximum Using Handheld Dynamometry

Isometric assessment of muscular function using a handheld dynamometer (HHD) is frequently used in clinic environments. However, there is controversy in terms of the validity of isometric assessment to monitor changes in dynamic performance. One repetition maximum (1RM) is considered the gold standard for evaluating dynamic strength, though clinicians do not often use 1RM testing, preferring to be cautious with clients who have preexisting impairments. If strength testing using an HHD could be used to predict 1RM, this may have significant implications for the use of isometric testing to prescribe exercise in clinical environments.

Effect of prophylactic ankle taping on ankle and knee biomechanics during basketball-specific tasks in females

OBJECTIVE The aim of this study was to investigate the effects of ankle taping on ankle and knee joint biomechanics during cutting and rebound activities in females. DESIGN Cross-sectional. SETTING Laboratory. PARTICIPANTS Twenty semi-professional female basketball players performed a cut and rebound task under two conditions (taped and no-tape). MAIN OUTCOME MEASURES Kinematic and ground reaction force data were collected during the deceleration phase of each movement task. RESULTS Taping resulted in a significant reduction in peak ankle dorsiflexion, inversion and internal rotation angles and range of motion (ROM) at the ankle joint; and reduced knee ROM in the sagittal plane during the rebound task only. Taping significantly reduced peak knee flexion moment (0.29 Nm/kg, P = 0.013) and increased knee internal rotation moment (0.63 Nm/kg, P = 0.026) during the cutting task compared to control. Taping also significantly reduced the internal rotation moment (0.07 Nm/kg, P = 0.025), and medial shear forces (0.14 N/kg, P = 0.012) in the rebound task. CONCLUSION Results of the study suggest that ankle taping restrict ankle range of movement in the rebound task only and ankle taping appears to have upstream effects on the knee, which may have injury implications.

Muscle morphology of the lower leg in ambulant children with spastic cerebral palsy: Gross Morphology in Children With Spastic CP

Introduction: In this study we aimed to determine the lower limb morphological characteristics of skeletal muscle of ambulant children with spastic cerebral palsy (CP) and typically developing (TD) children. Methods: Seventeen children with spastic diplegic CP (10 boys and 7 girls, 5–12 years of age, Gross Motor Function Classification System [GMFCS] level I or II) and 19 TD children (8 boys and 11 girls, 5–11 years of age) underwent lower limb T1‐weighted MRI. Morphological characteristics of the triceps surae, including muscle volume, anatomical cross‐sectional area, muscle length, and subcutaneous adipose tissue, were digitally quantified, and the proportional distribution calculated. Results: Children with GMFCS II had significantly reduced muscle volume, cross‐sectional area, and muscle length, and increased subcutaneous fat compared with TD children. Children classified as GMFCS II consistently exhibited the greatest deficits in all morphology variables. Discussion: Morphological variables were significantly different between the groups. These alterations have the potential to influence the functional capabilities of the triceps surae muscle group. Muscle Nerve 58:818–823, 2018

Measurement of muscle thickness of the serratus anterior and lower trapezius using ultrasound imaging in competitive recreational adult swimmers, with and without current shoulder pain

OBJECTIVES To compare serratus anterior and lower trapezius muscle thickness between swimmers with and without current shoulder pain, and between sides when measured by real-time ultrasound imaging. DESIGN A single blinded age and gender-matched case-control study with 26 symptomatic and 26 asymptomatic recreational swimmers. METHODS Muscle thickness of serratus anterior and lower trapezius were measured using previously validated real-time ultrasound imaging protocols. Serratus anterior thickness was measured in side lying with 90° of glenohumeral flexion at rest and during a scapular protraction contraction. Lower trapezius thickness was measured in prone with 145° of glenohumeral abduction whilst at rest and when holding the weight of the arm. RESULTS There was no statistically significant difference between the muscle thickness of serratus anterior and lower trapezius between the symptomatic shoulder and the dominance-matched shoulder in the asymptomatic group of swimmers. There was also no significant difference in muscle thickness between the symptomatic side and asymptomatic side within the symptomatic group. CONCLUSIONS There appears to be no difference in serratus anterior and lower trapezius thickness between swimmers who have mild to moderate shoulder pain, who continue to swim and those who do not have shoulder pain. When imaging the serratus anterior and lower trapezius in swimmers with mild shoulder pain, clinicians should expect no differences between sides. If muscle thickness differences between sides are detected in recreational swimmers, this may indicate that the swimmer is participating in other asymmetrical activities or has a higher level of shoulder pain.

Biomechanical correlates of running performance in active children

OBJECTIVES Examine the running kinematics in healthy, physically active prepubescent children and to determine if specific biomechanical factors correlate with running performance. DESIGN Cross-sectional study. METHODS Fifteen children (age 9years, ±11months) completed a 1km time trial before undergoing three-dimensional running motion analysis. RESULTS A strong positive correlation was observed between the biomechanical variables of stride length (p<.01), contact time (p<.01) and ankle dorsiflexion angle (p=.04) with time trial performance. Between variable analyses revealed a strong positive correlation between peak angles of hip adduction and knee flexion. There was no correlation between hip adduction and knee flexion peak angles or the vertical displacement of centre of mass with trial performance. CONCLUSIONS The results of this study show that children with a better time trial performance display longer stride length, shorter contact time and mid or forefoot strike pattern. These findings have implications for targeted technique intervention in childrens running training to improve running performance.

Evaluating the effectiveness of home exercise programmes using an online exercise prescription tool in children with cerebral palsy: protocol for a randomised controlled trial

Introduction Children with cerebral palsy (CP) and other neurodevelopmental disabilities often receive a home programme of exercises to assist in reaching their therapy goals. Adherence to exercise programmes is necessary to attain the level of practice required to achieve goals; however, adherence can be difficult to accomplish. In this paper, we describe the protocol for a randomised controlled trial to evaluate the effectiveness of delivering a home exercise programme to school-age children with disabilities using Physitrack, an online exercise prescription tool with a website or app interface. Methods and analysis Participants aged 6–17 years, with CP or other neurodevelopmental disabilities, receiving community physiotherapy services in Western Australia, will be recruited. Participants will be stratified by age and functional mobility and randomised to either the intervention group, who will complete an 8-week home exercise programme using Physitrack, or the control group, who will complete an 8-week exercise programme without Physitrack. Researcher blinding to group allocation, and participant blinding to outcome, will be maintained. The primary outcome measures are adherence to the home exercise programme with weekly collection of home exercise logs; achievement of individualised goals by phone interview before and after intervention; and correctness of exercise performance by collection and analysis of videos of participants performing home exercises. Secondary outcome measures include enjoyment of physical activity, confidence to complete exercise programme, preferred method of delivery of programme and usability of Physitrack. A sample size of 58 participants will be necessary to see an effect on home programme adherence. Data will be analysed using the intention-to-treat principle. Ethics and dissemination Ethical approval was obtained from Curtin University Human Research Ethics Committee in July 2016 (10391). Outcomes will be disseminated through publication in peer-reviewed journals and presentations at scientific conferences. Trial registration number ACTRN12616000743460; Pre-results.

Differences in Scapular Orientation Between Standing and Sitting Postures at Rest and in 120° Scaption: A Cross-Sectional Study

Scapular orientation may be influenced by static body posture (sitting and standing) and contribute to the development of shoulder pain. Therefore, a consistent body posture should be considered when assessing scapular orientation as well as enhancing optimal scapular positioning.

Reliability and Validity of the Measurement of Scapular Position Using the Protractor Method

Background The protractor method is a proposed clinical assessment tool, the first to measure vertical scapular position, that directly compares scapular and spinal landmarks. This tool has the potential to reliably and accurately measure excessive scapular elevation or depression. Objective The purpose of this study was to determine reliability and validity of the protractor method to measure resting scapular position. Design An interrater and intratester reliability and validity study was conducted. Methods Testing was conducted on the same day by 2 physical therapists who were blinded to each others results. The vertical distances between the spinous process of C7 and the superior margin of the medial aspect of the spine of the scapula (C7 method) and the spinous process of T8 and the inferior angle of the scapula (T8 method) were palpated and measured on the symptomatic shoulder in 34 people with current shoulder pain using the protractor method. Measurements were compared with 2-dimensional camera analysis to assess validity. Results For intertester reliability, the standard error of measure, minimal detectable change, and intraclass correlation coefficient were 6.3 mm, 17.3 mm, and .78, respectively, for the C7 method and 5.7 mm, 15.7 mm, and .82, respectively, for the T8 method. For intratester reliability, the standard error of measure, minimal detectable change, and intraclass correlation coefficient were <0.9 mm, <2.5 mm, and .99, respectively. For validity, significant correlations (r) and mean differences were .83 and 10.1 mm, respectively, for the C7 method and .92 and 2.2 mm, respectively, for the T8 method. Limitation The results of this study are limited to static measurement of the scapula in one plane. Conclusion Both protractor methods were shown to have good reliability and acceptable validity, with the T8 method demonstrating superior clinical utility. The clinical use of the T8 method is recommended for measurement of excessive resting scapular elevation or depression.