Pre-and post-operative biomechanics in femoroacetabular impingement patients during level walking

Abstract

Femoroacetabular impingement (FAI) is a hip bony morphology that causes intra-articular damage that may lead to osteoarthritis. Changes in level walking gait, including abnormal reversals, have been seen previously. Three participants with FAI and labral tears were compared to healthy controls pre-operatively, three, and six month post-operatively. Changes were seen within the FAI group and compared to the control group. Increases in survey scores indicated an increase in activity levels. Peak dorsiflexion was increased pre-operatively compared to controls and to three and six months post-operatively. Peak propulsive force and peak ground reaction force were increased at three and six months post-operatively. Sagittal plane hip excursion was also increased at six months post-operatively compared to pre-operatively. Magnitude and duration of abnormal reversals were decreased in one FAI participant but increased in another participant. The prevalence of abnormal reversals remained the same in two participants. The change of the hip angle through the reversal was decreased. These changes may be attributed to an increase in ankle strategy while walking to a near normal level and a decrease in the hip strategy seen pre-operatively. The increase in hip sagittal plane excursion has been seen and may indicate the surgery is effective. In conclusion, walking gait biomechanics are affected by FAI and can be changed with arthroscopic surgery. Different strategies may be used to compensate for pain.