Validation of Static and Dynamic Balance Assessment Using Microsoft Kinect for Young and Elderly Populations.

Reduction in balance is an indicator of fall risk, and therefore, an accurate and cost-effective balance assessment tool is essential for prescribing effective postural control strategies. This study established the validity of the Kinect v2 sensor in assessing center of mass (CoM) excursion and velocity during single-leg balance and voluntary ankle sway tasks among young and elderly subjects. We compared balance outcome measures (anteroposterior (AP) and mediolateral (ML) CoM excursion and velocity and average sway length) to a traditional three-dimensional motion analysis system. Twenty subjects (10 young: age = y, height cm, weight kg; 10 elderly: age y, height cm, weight kg), with no history of lower extremity injury, participated in this study. Subjects performed six randomized trials; four single-leg stand (SLS) and two ankle sway trials. SLS and voluntary ankle sway trials showed that consistency (ICC(2, k)) and agreement (ICC(3, k)) for all variables when all subjects were considered, as well as when the elderly and young groups were analyzed separately. Concordance between systems ranged from poor to nearly perfect depending on the group, task, and variable assessed.

Conversion of fused hip to total hip arthroplasty with presurgical and postsurgical gait studies.

This case study presents a subject with a fused hip converted to total hip arthroplasty. Kinematic gait analysis was conducted on 3 occasions, presurgery, 4 months postsurgery, and 2.5 years postsurgery. Presurgery data showed decreased cadence and shorter step length; sound limb possessed increased hip, knee range of motion (ROM), and increased knee flexion during stance; the affected limb had minimal hip motion and normal knee ROM with abnormal pattern. At 4 months postsurgery, the sound limb showed decreased step length, whereas the affected limb showed increased knee extension during stance and increased hip ROM. Data obtained at 2.5 years postsurgery indicated decreased cadence and speed and increased ROM in both limbs. The total hip arthroplasty had provided relief of chronic back and affected hip pain and improved mobility. Gait-specific training is recommended.