Kinematics and kinetics during gait in symptomatic and asymptomatic limbs of children with myelomeningocele.

BACKGROUND

Knee pain and early arthrosis have emerged as significant problems in young adults with myelomeningocele (MMC). The purpose of our study was to examine kinematics and kinetics during gait in symptomatic and asymptomatic limbs of children with an MMC to better understand the factors that may predispose individuals with an MMC to potentially debilitating knee problems.

METHODS

Seven children with L3-L4 level MMC and 8 age-matched typically-developing control children participated in this study. Three-dimensional kinematic and kinetic data were obtained bilaterally during gait. A custom-designed femoral tracking device, with established reliability and validity was used to track the thigh. The limbs in an MMC group were subdivided into 2 subgroups (n=6 and 8, symptomatic and asymptomatic, respectively) based on history of pain at the knee joint after walking/weight bearing activity in the last 6 months. An 1-way analysis of variance with post hoc Bonferroni adjustments was used to compare lower extremity kinematic and kinetic variables between symptomatic, asymptomatic, and control limbs. The Pearson product moment correlation (r) was used to assess the relationship between variables of interest.

RESULTS

Symptomatic limbs showed increased knee flexion in stance (P=0.01) compared with asymptomatic limbs. Symptomatic limbs showed trends toward increased knee extension, adduction, and internal rotation moments (P=0.031, P=0.025, and P=0.024, respectively) compared with asymptomatic limbs. Hip internal rotation was positively associated with knee internal rotation moment (r=0.93, P=0.008 and r=0.76, P=0.08 in symptomatic and asymptomatic limbs, respectively) and increased knee adduction moment (r=0.84, P=0.03 and r=0.91, P=0.01 in symptomatic and asymptomatic limbs, respectively).

CONCLUSIONS

Symptomatic limbs in children with an MMC showed increased knee flexion and trends toward higher extension, adduction, and internal rotation moments. Increased knee flexion accompanied by inadequate control of hip transverse kinematics may have significant implications for knee joint loading in this population.

LEVEL OF EVIDENCE: Level 4 (Case series with controls, motion laboratory gait analysis).