Sonoelastography of the Achilles Tendon: Prevalence and Prognostic Value Among Asymptomatic Elite Australian Rules Football Players.

OBJECTIVE: To investigate the prevalence of sonographic abnormalities at the mid-Achilles tendon among a cohort of asymptomatic professional football players and to determine whether these sonographic abnormalities predict midportion Achilles tendon symptoms. DESIGN: Longitudinal study. SETTING: A single competitive season in the Australian Rules Football League. PARTICIPANTS: Forty-two elite Australian Rules football players. MAIN OUTCOME MEASURES: Using ultrasound and sonoelastography, 42 players were examined at baseline and again 9 months later (postseason) for the existence of intratendinous hypoechogenicity, delamination, softening, and neovascularization. The anterio-posterior (AP) thickness and cross-sectional area (CSA) were measured. Players reporting Achilles tendon pain or with Victorian Institute of Sports Assessment-Achilles scores below 80 at the end of the season were classified as symptomatic. RESULTS: At preseason, ultrasound and/or sonoelastographic abnormalities were found in 22 (22/42, 52.4%) asymptomatic players. Baseline AP thickness and CSA were significantly greater in symptomatic players at the end season than those in asymptomatic players (0.57 ± 0.05 cm vs 0.50 ± 0.03 cm; P < 0.001 and 0.67 ± 0.07 cm vs 0.57 ± 0.06 cm; P < 0.001, respectively). The presence of intratendinous softening and delaminations at baseline was associated with pain onset during the season (P = 0.046; P = 0.048, respectively). CONCLUSIONS: Ultrasound and sonoelastography-detected abnormalities were relatively common among the asymptomatic footballers. Greater AP thickness and CSA and also the presence of intratendinous softening and delaminations were associated with the increased risk of developing symptoms. CLINICAL RELEVANCE: Conventional ultrasound supplement with sonoelastography may be able to identify elite athletes at risk of Achilles tendon injury, which may, in turn, impact therapeutic decisions.

Pitching mechanics and performance of adult baseball pitchers: A systematic review and meta-analysis for normative data.

OBJECTIVES: The aim of this systematic review was to critically review and synthesise the findings from primary studies on pitching mechanics and performance of healthy adult baseball pitchers. DESIGN: Systematic review with meta-analysis. METHODS: Eight English- and Japanese-language databases were systematically searched from inception to 22nd July 2022. RESULTS: In total, 29 descriptive biomechanical studies were included. Overall study quality was moderate. In subgroup analyses, professional pitchers showed significantly higher stride length, peak shoulder internal rotation velocity, peak shoulder proximal force and ball velocity compared to collegiate pitchers. Conversely, collegiate pitchers were found to have significantly higher peak pelvis rotation velocity. CONCLUSIONS: Available normative data suggested potentially heterogeneous pitching mechanics and performance between professional and collegiate pitchers. However, the findings in this review should be interpreted cautiously. Since statistical heterogeneity was significant within most data sets, more detailed subgroup analyses are required. Additionally, more high-quality studies utilising measurement systems with established reliability are required to obtain accurate data in baseball pitching mechanics and performance.

Risk Factors of Shoulder and Elbow Injuries in Baseball: A Scoping Review of 3 Types of Evidence.

BACKGROUND: Shoulder and elbow overuse injuries are the most common problems in baseball players. No scoping review has compared the findings from different types of evidence. PURPOSE: To map the broad evidence from 3 types of evidence (epidemiological, biomechanical, and narrative) on potential risk factors for shoulder and elbow injuries in baseball and identify gaps in the existing literature to guide future research. STUDY DESIGN: Scoping review. METHODS: Eight electronic databases were searched from inception to May 14, 2020. Any peer-reviewed papers that investigated or discussed potential risk factors for shoulder and elbow injuries in baseball were included. RESULTS: A total of 302 studies (107 epidemiological studies, 85 biomechanical studies, and 110 narrative reviews) were included. Risk factors were categorized into 9 domains: sports profiles, physical characteristics/functions, pitching mechanics, performance, behavioral, psychosocial, biological and developmental, injury/sports profiles, and environmental factors. Studies were consistent in supporting limited shoulder range of motion (ROM) and player positions (pitchers or catchers) as risk factors for shoulder injuries. For elbow injuries, the majority of the included studies suggested that being pitchers or catchers and working with higher ball velocity can be risk factors. CONCLUSION: Findings were consistent in some risk factors, such as limited shoulder ROM and positions. However, findings were inconsistent or limited for most factors, and substantial research gaps were identified. Research assessing those factors with inconsistent or limited evidence in the current literature were recognized to be priorities for future studies.

Reliability of a portable fixed frame dynamometry system used to test lower limb strength in elite Australian Football League players.

OBJECTIVES: Deficits in strength of lower limb musculature have been associated with increased injury risk in a variety of athletic populations. As medical and performance staff seek to better understand the association between hip and knee strength measures and injury risk, measurement tools with high reliability and utility are required to profile and manage athletes effectively. The purpose of this study was to investigate the test-retest reliability of a portable fixed frame dynamometry system used to assess hip and knee strength of an elite Australian Football League team. DESIGN: Case series. METHODS: Maximum voluntary isometric strength of the hip abductors, hip adductors and knee flexors of 41 elite male Australian Football League footballers (mean age=23.7±4.1 years, height=189.2±7.0cm, weight=88.6±8.4kg) were tested during preseason training. Tests were performed one week apart on the same training day of a standard preseason week. RESULTS: Test-retest reliability was very high for left hip adduction (ICC 0.958), right hip adduction (ICC 0.955), left hip abduction (ICC 0.957), right hip abduction (ICC 0.945), left knee flexion (ICC 0.927) and right knee flexion (ICC 0.923). Furthermore, standard errors of measurement in per cent (SEM%) ranged from 3.21 to 5.03%, and minimal detectable change (MDC) from 3.93 to 6.65kg for the different hip and thigh strength measures, making it possible to determine small changes in strength at the individual level. CONCLUSIONS: This study demonstrated very high reliability when testing maximal voluntary isometric hip and knee strength using a portable fixed dynamometry system (KangaTech) in an elite male Australian Football League setting.

The safety, efficacy and cost-effectiveness of the Maxm Skate, a lower limb rehabilitation device for use following total knee arthroplasty: study protocol for a randomised controlled trial.

BACKGROUND: Physical rehabilitation is required to enhance functional outcomes and overall recovery following total knee arthroplasty (TKA). However, there are no universally accepted clinical guidelines available to consistently structure rehabilitation for TKA patients. A common method is rehabilitation provided in an outpatient setting, on a one-to-one treatment basis. This method is resource-intensive and outcomes must be compared to less costly alternatives such as home-based rehabilitation. The current study will analyse a novel home-based rehabilitation program. The Maxm skate is a portable, lower-limb, postoperative, rehabilitation exercise device for individual use in a hospital or home-based setting. This study was developed to compare the safety, efficacy and cost-effectiveness of the Maxm Skate rehabilitation program to standard rehabilitative care following TKA. The primary outcome is the range of motion (ROM) achieved by patients who received the Maxm Skate program compared to standard care at three months post TKA. Secondary outcomes include patient-reported outcomes, costs and functional evaluations which will be collected at multiple time-points up to 12 months after TKA. METHODS: This is a single-blinded, randomised controlled trial (RCT) in which 116 eligible participants consented for primary TKA will be randomly allocated to receive either the Maxm Skate rehabilitation program or standard rehabilitative care. Fifty-eight participants per group will provide 90% power (α = 0.05) to detect 10° of difference in ROM between groups at three months after TKA, assuming a within-group standard deviation of 16° and allowing for 5% loss to follow-up. Participants randomised to the Maxm Skate group will use the skate device and accompanying iOS App and sensors to complete rehabilitation exercises, as outlined in the Maxm Skate Rehabilitation Guide. Outcomes will be compared to those receiving standard rehabilitative care. A blinded physiotherapist will evaluate functional outcomes preoperatively and at 2, 4, 6, 12, 26 and 52 weeks after TKA. The functional assessment will include measures of knee ROM, pain, isometric knee strength, balance and knee/thigh circumference. Limited measures will also be assessed at day 2 postoperatively by an alternate, unblinded physiotherapist. Clinical outcome measures will be administered preoperatively and at 6, 12 and 52 weeks postoperatively. An economic evaluation will be conducted and participants will be screened for adverse event occurrences from the time of consent to 12 months postoperatively. DISCUSSION: This RCT will be the first to investigate the safety, efficacy and cost-effectiveness of the home-based Maxm Skate Rehabilitation program, in comparison to standard rehabilitative care following primary TKA. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12616001081404p . Registered on 11 August 2016.

Computational modelling of phonological dyslexia: how does the DRC model fare?

This paper investigates the patterns of reading impairment in phonological dyslexia using computational modelling with the dual-route cascaded model of reading (DRC, Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001). Systematic lesioning of nonlexical and phonological processes in DRC demonstrates that different lesions and severity of those lesions can reproduce features of phonological dyslexia including impaired reading of nonwords, relatively spared reading of words, an advantage for reading pseudohomophones. Using the same stimuli for model and for patients, lesions to DRC were also used to simulate the reading accuracy shown by three individuals with acquired phonological dyslexia. No single lesion could replicate the reading performance of all three individuals. In order to simulate reading accuracy for one individual a phonological impairment was necessary (addition of noise to the phoneme units), and for the remaining two individuals an impairment to nonlexical reading procedures (increasing the time interval between each new letter being processed) was necessary. We argue that no single locus of impairment (neither phonological nor nonlexical) can account for the reading impairments of all individuals with phonological dyslexia. Instead, different individuals have different impairments (and combinations of impairments) that together provide the spectrum of patterns found in phonological dyslexia.