KINEMATIC ATTRIBUTES ASSOCIATED WITH OVERARM THROWING PERFORMANCE IN CRICKET

The purpose of this study was to identify the kinematic attributes associated with throwing performance (ball velocity and accuracy) in cricket. Three-dimensional motion analysis of sixteen cricketers performing 30 ground-fielding attempts towards a target from three approach directions (straight, non-dominant and dominant) was captured. Vertical release angle, stride length, trunk flexion velocity & forward trunk tilt angle at release were significant predictors of ball velocity across the three approach conditions. Horizontal release angle was a significant predictor of throw accuracy in all three approaches. ANOVAs revealed that throws were significantly quicker from the straight approach, and significantly more accurate in the dominant and straight conditions. Throwing performance and mechanical attributes of throwing technique differ by approach direction constraint

Evaluating the Biomechanics of the Pediatric Foot in Turner Syndrome

Turner syndrome is a genetic disorder that can present clinically with multiple concurrent comorbidities. This case report describes a 12-year-old girl with Turner syndrome who was referred for podiatric medical assessment and explores the application of optoelectronic stereophotogrammetry in the biomechanical assessment of the foot and lower limb. A four-segment kinematic foot model using 14-mm reflective markers was applied to the foot and lower limb of the patient to track motion at the tibia, rearfoot, forefoot, and hallux. Kinematic results presented in this case study illustrate evidence of excessive foot pronation throughout the stance phase of gait. Whether excessive pronation is a general characteristic of foot function in Turner syndrome remains to be confirmed, but the findings presented suggest that a comprehensive evaluation of foot biomechanics in patients with Turner syndrome may be warranted

Evaluation of multi-segmental kinematic modelling in the paediatric foot using three concurrent foot models

Background: Various foot models are used in the analysis of foot motion during gait and selection of the appropriate model can be difficult. The clinical utility of a model is dependent on the repeatability of the data as well as an understanding of the expected error in the process of data collection. Kinematic assessment of the paediatric foot is challenging and little is reported about multi-segment foot models in this population. The aim of this study was to examine three foot models and establish their concurrent test-retest repeatability in evaluation of paediatric foot motion during gait. Methods: 3DFoot, Kinfoot and the Oxford Foot Model (OFM) were applied concurrently to the right foot and lower limb of 14 children on two testing sessions. Angular data for foot segments were extracted at gait cycle events and peaks and compared between sessions by intraclass correlation coefficient (ICC) with 95% confidence intervals (95% CI) and standard error of measurement (SEM). Results: All foot models demonstrated moderate repeatability: OFM (ICC 0.55, 95% CI 0.16 to 0.77), 3DFoot (ICC 0.47, 95% CI 0.15 to 0.64) and Kinfoot (ICC 0.43, 95% CI −0.03 to 0.59). On the basis of a cut-off of 5°, acceptable mean error over repeated sessions was observed for OFM (SEM 4.61° ± 2.86°) and 3DFoot (SEM 3.88° ± 2.18°) but not for Kinfoot (SEM 5.08° ± 1.53°). Reliability of segmental kinematics varied, with low repeatability (ICC < 0.4) found for 14.3% of OFM angles, 22.7% of 3DFoot angles and 37.6% of Kinfoot angles. SEM greater than 5° was found in 26.2% of OFM, 15.2% of 3DFoot, and 43.8% of Kinfoot segmental angles. Conclusion: Findings from this work have demonstrated that segmental foot kinematics are repeatable in the paediatric foot but the level of repeatability and error varies across the segments of the different models. Information on repeatability and test-retest errors of three-dimensional foot models can better inform clinical assessment and advance understanding of foot motion during gait

Current Understanding of the Impact of Childhood Obesity on the Foot and Lower Limb

Childhood obesity has emerged in recent years as a major public health problem. As this continues to concern across local, national and international populations, and as our understanding of obesity advances, access to multi-disciplinary care and understanding of the complications is warranted. Recent findings have suggested that the musculoskeletal system is one of the multiple body systems compromised by obesity and that aberrant biomechanical function may be a precursor to the onset of musculoskeletal symptoms. This review will consider childhood obesity and its impact on the paediatric foot and lower limb through examination of literature on foot structure and biomechanics of gait. An overview of evidence-based management is out with the context of this review, however some recommendations for clinical practice will be proposed

Segmental and Intersegmental Coordination Characteristics of a Cognitive Movement Control Test: Quantifying Loss of Movement Choices

Cognitive movement control tests are hypothesized to reveal reduced coordination variability, a feature of motor behaviour linked to clinical presentations. Exploration of this proposition via kinematic analysis of test pass and fail conditions is yet to be conducted. Kinematics (3D) were collected as 28 participants were qualitatively rated during nine trials of a cognitive movement control test. Ten female and two male participants passing the test were matched to twelve participants who failed (three males, nine females). Sagittal plane pelvis and knee angles were determined. Peak pelvic deviation and knee flexion maxima/minima were compared between groups. Classification tree analysis explored relationships between test failure and pelvis–knee intersegmental coordination strategy classifications derived from novel and traditional vector coding techniques. Coordination variability waveforms were assessed via SPM. Age, BMI, and knee flexion values did not differ between the groups (p > 0.05); however, participants rated as failing the test displayed greater pelvic deviation (p < 0.05). Classification tree analysis revealed a greater use of pelvic dominant intersegmental coordination strategies from both vector coding techniques (p < 0.001) by fail-group participants. The fail-group also displayed lower coordination variability for novel (p < 0.05), but not traditional (p > 0.05) vector coding technique waveforms, supporting the premise that the testing protocol may act as a qualitative approach to inform on features of motor behavior linked to clinical presentations

Is neuromuscular inhibition detectable in elite footballers during the Nordic hamstring exercise?

The presence of neuromuscular inhibition following injury may explain the high incidence of biceps femoris injury recurrence in elite (soccer) footballers. This phenomenon may be detectable in elite players during the Nordic hamstring exercise. Thus, the first purpose of this study was to assess biceps femoris muscle activation during this exercise in players with hamstring injury history. Additionally, following injury, observed increases in synergistic muscle activation may represent a protective mechanism to the presence of neuromuscular inhibition. Thus, the second purpose was to identify if the relative contributions of biceps femoris, and its synergists reflected a post-injury pattern of activation suggestive of these potentially compensatory neural mechanisms. Ten elite players with a history of hamstring injury and ten elite players without a history of hamstring injury, completed six repetitions of the Nordic hamstring exercise. During each trial, biceps femoris, semitendinosus and gluteus maximus muscle activations were collected at 90-30° and 30-0° of knee flexion. Biceps femoris activation was significantly higher at 90-30° of knee flexion compared to 30-0° (P < 0.001) but did not differ between the groups. In players with a history of injury, muscle activation ratios for the biceps femoris/semitendinosus (P = 0.001) and biceps femoris/gluteus maximus (P = 0.023) were significantly greater at 30-0° of knee flexion than in the control group. Neuromuscular inhibition of the biceps femoris was not detected during the exercise within elite footballers, yet the relative contributions of biceps femoris and its synergists appear to change following injury. [Abstract copyright: Copyright © 2018 Elsevier Ltd. All rights reserved.