Introduction: Concussion is a significant injury in collision sports and manifests itself via a multitude of symptoms including dizziness, altered proprioception, balance, and spinal control. Furthermore, sustaining a concussion significantly increases the risk of sustaining another concussion, and is attributed to higher musculoskeletal injury in the ensuing 12 months. Reasons for this are unclear and further investigations into the effects of concussion may improve physiotherapy management of concussed patients.

Objective To examine whether physical measurements of the sensorimotor system predict concussion incurred by footballers. Design Prospective cohort study. Setting Australian professional sport setting. Participants Fifty-three rugby union and rugby league players. Assessment of risk factors Physical measurements including balance (sway across six test conditions), vestibular function (assessments of oculo-motor and vestibular ocular reflex) and spinal control (cervical joint position error and trunk muscle size and contraction ability) were performed during the preseason. Outcome measures Concussion injuries during the season were diagnosed and recorded by club medical staff. Results Age, height, weight, and years playing football were not associated with concussion in the season (p=0.43, 0.43, 0.19, 0.25). Preseason cross-sectional area of the multifidus muscle at the L5 vertebral level was 10% smaller in players who went on to sustain a season concussion compared to those who did not: mean difference (95% confidence interval) 1.0 cm 2 (0.1 cm 2 to 1.9 cm 2 ), p=0.031. This difference in size was moderate (effect size 0.7) and exceeds the minimal detectable change of 0.4 cm 2 . There were no significant differences observed for the other measures, p>0.05. Conclusions Optimal spinal control is likely to be a key requirement in a physically demanding sport such as football. The multifidus is one of the muscles crucial for spinal control, and our findings report this measure to be predictive of footballers sustaining a concussion. This novel finding provides preliminary evidence that warrants further investigation as to the possible importance of spinal control in prevention programs Competing interests None.

Background: Head and neck injuries are common in the Australian Football League (AFL). Previous studies have shown that size and function of trunk muscles are predictive of lower limb injuries in professional AFL players. The position and control of the trunk allows safe production, transfer and control of forces and motion to and from the distal segments and could be an equally important consideration for the upper body. The aim of this study was to examine whether trunk muscle measurements predict head/neck injuries incurred by professional AFL players.

Background: Sports concussion is a risk for players involved in high impact, collision sports. Postconcussion, the majority of symptoms subside within 7e10 days, but can persist in 10e20% of athletes. Understanding the effects of sports concussion on sensorimotor systems could inform physiotherapy treatment.Objective: To explore changes in sensorimotor function in the acute phase following sports concussion. Design: Prospective cohort study.Methods: Fifty-four players from elite rugby union and league teams were assessed at the start of the playing season. Players who sustained a concussion were assessed three to five days later. Measures included assessments of balance (sway velocity), vestibular system function (vestibular ocular reflex gain; right-left asymmetry), cervical proprioception (joint position error) and trunk muscle size and function.Results: During the playing season, 14 post-concussion assessments were performed within 3-5 days of injury. Significantly decreased sway velocity and increased size/contraction of trunk muscles, were identified. Whilst not significant overall, large inter-individual variation of test results for cervical proprioception and the vestibular system was observed.Limitations: The number of players who sustained a concussion was not large, but numbers were comparable with other studies in this field. There was missing baseline data for vestibular and cervical proprioception testing for some players.Conclusions: Preliminary findings post-concussion suggest an altered balance strategy and trunk muscle control with splinting/over-holding requiring consideration as part of the development of appropriate physiotherapy management strategies. (C) 2017 Elsevier Ltd. All rights reserved.

BACKGROUND:Head and neck injuries are common in football. Injuries such as concussion can have serious consequences. Previous studies have shown that size and function of trunk muscles are predictive of lower limb injuries in professional Australian Football League (AFL) players. It is unknown whether measurement of trunk muscles can also be used to predict head and neck injuries.OBJECTIVES:To examine whether trunk muscle measurements predict head and neck injuries incurred by professional AFL players.DESIGN:Prospective cohort study.METHOD:Ultrasound imaging of trunk muscles was performed on 165 professional AFL players at the start of the pre-season and 168 players at the start of the playing season. Injury data were obtained from records collected by the AFL club staff during the playing season.RESULTS/FINDINGS:The ability to contract the multifidus (MF) muscle at the L5/S1 vertebral level at the start of pre-season and start of the playing season predicted head and neck injury in the playing season. Sensitivity and specificity of the model were 56.3% and 76.6% for the pre-season and 50.0% and 77.2% for the playing season respectively.CONCLUSIONS:A model with potential clinical utility was developed for prediction of head and neck injuries in AFL players. These predictive values will need to be validated in other teams. Ability to contract MF is modifiable and this information could be incorporated into pre-season injury prevention programs.

Measurement reliability of the L4/5 lumbar multifidus (MF) muscles is high in older adults, but few studies have investigated measurement reliability of the abdominal and upper lumbar MF muscles in this age group.Objectives: To determine measurement reliability of abdominal and lumbar MF muscles from a single ultrasound (US) image in older adults.Methods: Resting thickness of rectus abdominis and obliquus externus, resting and contracted thickness of obliquus internus, transversus abdominis and lumbar MF, and resting cross-sectional area (CSA) of MF levels (L2-5) were obtained from US images of 92 community-dwelling older adults (aged 65-89 years). Measurements of images were undertaken by an experienced rater and repeated 7-10 days later for intra-rater, and by a second expert rater for inter-rater calculations. Intra-rater reliability was estimated for all muscles. Inter-rater reliability was estimated for all abdominal muscles and for L5 multifidus. Reliability was estimated by intraclass correlation coefficients (ICC).Results: Intra-rater ICC(3,1) and inter-rater ICC(2,1) of resting thickness measures of all muscles and CSA of MF were >= 0.86. The ICCs for percentage thickness change were >= 0.76 for the abdominal muscles, and >= 0.42 for MF.Conclusions: Measurement reliability of US imaging for abdominal and MF muscle thickness and MF CSA was high, and consistent with previous findings for younger adults. Reliability of percentage thickness change was lower suggesting caution is needed when using this as an outcome measure or study factor among older adults. (C) 2016 Elsevier Ltd. All rights reserved.