The effects of joint hypermobility syndrome on the kinematics and kinetics of the vertical jump test.

Purpose: Biomechanical impairments are not apparent during walking in people with Joint Hypermobility Syndrome (JHS). This research explored biomechanical alterations during a higher intensity task, vertical jumping.

Materials And Methods: This cross-sectional study compared a JHS group (n = 29) to a healthy control group (n = 30). Joint kinematics and kinetics were recorded using a Qualisys motion capture system synchronized with a Kistler platform. Independent sample t-tests and standardised mean differences (SMD) were used for statistical analysis.

Results: No significant statistical or clinical differences were found between groups in joint kinematics and jump height (p ≥ 0.01). Sagittal hip and knee peak power generation were statistically lower in the JHS group during the compression phase (p ≤ 0.01), but not clinically relevant (SMD < 0.5). Clinically relevant reductions were found in the JHS group knee and ankle peak moments during the compression phase, and hip and knee peak power generation during the push phase (SMD ≥ 0.5), although these were not statistically significant (p ≥ 0.01).

Conclusion: The JHS group achieved a similar jump height but with some biomechanical alterations. Further understanding of the joint biomechanical behavior could help to optimize management strategies for JHS, potentially focusing on neuromuscular control and strength/power training.