Do asymptomatic generalised hypermobility and knee hyperextension influence jump landing biomechanics?

Abstract

Background The Landing Error Scoring System (LESS) identifies movement patterns associated with Anterior Cruciate Ligament (ACL) injury. Hypermobility and knee hyperextension may alter these patterns given that hypermobile individuals present higher injury rates. Methods Eighty-five individuals were tested using the LESS and Beighton hypermobility score. Spearman rank correlation coefficients were calculated to investigate relationships between LESS and Beighton scores. T-tests and two-proportion z-tests were performed to explore differences in LESS scores and proportion of participants at risk of injury between non-hypermobile and asymptomatic hypermobile individuals, and individuals with non-hyperextended and hyperextended knees. Results The mean LESS score was 5.4 ± 1.4 errors and the median (interquartile range) Beighton score was 2 (4) points. No significant relationship was found between LESS and Beighton scores (ρ = −0.08, p = 0.490). LESS scores and proportions of participants at risk between non-hypermobile (5.3 ± 1.5 errors, 67.8%) and asymptomatic hypermobile (5.4 ± 1.3 errors, 76.9%) individuals, and between individuals with non-hyperextended (5.6 ± 1.5 errors, 68.3%) and hyperextended (5.3 ± 1.4 errors, 77.3%) knees were comparable (p > 0.05). Conclusions Asymptomatic hypermobile and knee hyperextended individuals do not present more high injury risk movement patterns during landing tasks.