The influence of medial meniscus injury and meniscectomy on the variability of gait parameters.

Objective: Degenerative and biomechanical changes in the knee joint after partial medial arthroscopic meniscectomy are well known. However, no studies have assessed the variability of gait parameters before and after partial medial meniscectomy. The goal of this research was (1) to determine the variability of gait parameters at different speeds before and after meniscectomy and (2) to compare this variability to that of healthy controls.

Methods: The variability of spatial-temporal parameters was characterized by a coefficient of variance (CV), the percentage ratio of standard deviation and mean; on the other hand, the variability of angular parameters was characterized by a mean coefficient of variance (Mean CV), which is the average coefficient variance over all integer percents of normalized gait cycles. The spatial positions of the anatomical points for calculating gait parameters were determined in 20 young healthy controls and 20 patients preoperatively and 3 and 12 months after meniscectomy.

Results: Gait speed significantly influenced the CV of spatial-temporal parameters and the Mean CV of angular parameters. Gait parameter variability showed significant changes in patients prior to and 3 months after the partial medial meniscectomy compared to the healthy group. The variability of angular parameters still differed from the healthy group 12 months postoperatively.

Conclusions: The complexity of gait decreased if the walking speed differed from the self-selected speed. Prior to and after meniscectomy, the decreased variability of angular parameters on the affected side of patients represented decreased flexibility of joints. This led to decreased consistency in movements of the lower limbs from stride to stride, as shown by the increased variability of spatial-temporal parameters. A decrease in joint flexibility and consistency of movement can be associated with a decreased complexity of movement. Preoperatively and postoperatively, patients used the non-affected limb and pelvis obliquity for compensation to help stabilize their gait.