"Be an Airplane Pilot": A Bimanual 3D Motion Analysis in Children With Unilateral Cerebral Palsy

Maximal ball velocity is a significant performance indicator in many sports, such as baseball. Doppler radar guns are widely assumed to underestimate velocity. Accuracy increases as the cosine angle between the radar gun and the object decreases. The purpose of this study was to investigate the impact of player handedness and the location of the radar gun on the accuracy of ball velocity. Throws were analyzed in four conditions: the radar gun on the right side, throwing with the right arm, then with the left arm; and the radar gun on the left side, throwing with the right arm, then with the left arm. The Cronbach’s alpha for all four conditions showed α-values above 0.97; however, a paired t-test indicated significant differences between the 3D motion analysis and the radar gun. Bland–Altman plots show a high degree of scatter in all conditions. Results suggest that the radar gun measurements can be highly inconsistent when compared to 3D motion analysis.

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3D motion analysis of latissimus dorsi tendon transfer in patients with posterosuperior rotator cuff tears: Analysis of proprioception and the ability to perform ADLS

Orthopaedics & Traumatology Surgery & Research ◽

10.1016/j.otsr.2019.10.018 ◽

2020 ◽

Vol 106 (1) ◽

pp. 39-44

Author(s):

Pit Hetto ◽

Sarah Erhard ◽

Mirjam Thielen ◽

Sebastian I. Wolf ◽

Felix Zeifang ◽

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Keyword(s):

Rotator Cuff ◽

Motion Analysis ◽

Latissimus Dorsi ◽

Tendon Transfer ◽

Rotator Cuff Tears ◽

3D Motion ◽

3D Motion Analysis

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The relationship of hip rotation range, hip rotator strength and balance in healthy individuals

Journal of Back and Musculoskeletal Rehabilitation ◽

10.3233/bmr-181299 ◽

2020 ◽

Vol 33 (5) ◽

pp. 761-767

Author(s):

Yongwook Kim ◽

Seungmook Kang

Keyword(s):

Motion Analysis ◽

External Rotation ◽

Dynamic Balance ◽

Three Dimensional ◽

Camera Motion ◽

3D Motion ◽

3D Motion Analysis ◽

Balance Ability ◽

Analysis System ◽

The Relationship

BACKGROUND: Few studies have explored the relationship between muscle strength, range of motion (ROM), and balance in the horizontal plane of the hip joint using three-dimensional (3D) motion analysis. OBJECTIVE: We investigate the relationships of hip internal rotation (IR) and external rotation (ER) ROM, measured using a 3D motion capture system, with hip internal and external rotator strength and single-leg standing balance. METHODS: The participants were 40 healthy adults. Kinematic data on hip ROM were collected using an eight-camera motion analysis system. Hip rotational strength measurements were obtained using hand-held isometric dynamometry. A Single-leg standing test and a pendular test were conducted to evaluate static and dynamic balance ability using BioRescue. RESULTS: Significant correlations were found between hip strength and each variable measured during hip ROM assessments (p< 0.05). Significant positive correlations were found between the hip IR/ER strength ratio and the IR/ER ROM ratio (r= 0.72, p< 0.01). The subgroup with a normal IR/ER ratio of hip rotator strength and ROM showed significantly better dynamic balance ability than the subgroup with a hip rotator muscle imbalance (p< 0.05). CONCLUSIONS: There is a significant relationship between hip IR/ER strength and IR/ER ROM with a normal hip IR/ER strength and ROM ratio positively affecting dynamic balance ability.

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