Article

Both the hip and knee contralateral to a total hip replacement (THR) have an
increased risk of osteoarthritis (OA) progression, and ultimate joint
replacement. It is also known that abnormal gait contributes to OA progression.
For these reasons, we conducted a longitudinal analysis of contralateral hip and
knee gait during the first year after unilateral THR to determine whether
abnormal contralateral gait biomechanics emerge after THR. We analyzed the
sagittal plane dynamic range of motion and 3D peak external moments from the
asymptomatic hip and knee contralateral to a THR in a group of 26 subjects,
evaluated preoperatively, and 3, 12, 24, and 52 weeks after THR, and a group of
control subjects. We used t-tests and repeated measures ANOVA to test the
hypotheses that contralateral hip and knee gait parameters are normal
preoperatively, but change after THR. Preoperatively, the contralateral hip
abduction moment and the contralateral knee adduction, flexion, and external
rotation moments were significantly higher than normal in the THR group (p </=
0.048). Apart from the peak hip extension moment, which decreased three weeks
after surgery but returned to its preoperative value thereafter, there were no
longitudinal changes during the study period (p >/= 0.141). Preoperative gait
abnormalities persisted postoperatively. Notably, the contralateral knee
adduction moment was 32% higher than normal in the THR group. These results
indicate a biomechanical basis for the increased contralateral OA risk after
unilateral THR, and suggest that some patients may benefit from strategies to
reduce loading on the contralateral limb.
CI - Copyright (c) 2011 Elsevier B.V. All rights reserved.

Langue : ANGLAIS