Gait findings in the adolescent subject with a stiff hip.

ABSTRACT

BACKGROUND: Adolescent subjects with severe unilateral hip disease are often stiff and painful yet have limited surgical options. Although hip fusion has been used successfully to minimize pain, acquired gait compensations after arthrodesis are factors felt to lead to knee and back pain over time. However, these gait compensations may already be present in a person with a stiff hip. The purpose of this study was to describe the quantitative gait findings of the adolescent subject with a unilateral stiff hip and to determine whether these findings are similar to those of subjects presenting after arthrodesis. METHODS: This study was a retrospective review of 6 subjects seen in a motion analysis laboratory between 2005 and 2009 (age 13 to 17 y). All adolescents had been referred to the motion analysis laboratory for a routine clinical gait study. Subjects were selected for this study based on kinematic sagittal plane hip motion found to be < 25 degrees (mean 16.2 degrees). Diagnoses included Legg-Calvé-Perthes (3) and hip avascular necrosis (3). RESULTS: Compared with laboratory-based normative data, the following findings were significant increased arc of trunk and pelvic motion (sagittal, coronal); involved side--decreased arc of hip and knee motion (sagittal), decreased peak hip abduction in swing; contralateral side--increased arc of hip and knee motion (sagittal); and increased peak hip abduction in swing. CONCLUSIONS: Gait compensations in multiple planes and joints were identified in adolescent subjects with a unilateral stiff hip. These compensations are necessary for these subjects to generate forward progression in gait and are similar to deviations found after hip arthrodesis. Subjects with a stiff hip may already be at risk to develop pain and/or arthrosis in adjacent motion segments due to these obligatory gait characteristics. Hip fusion may not increase these risks (in this patient population) since the compensations are already present and requisite, but may provide an opportunity to decrease pain and improve function. LEVEL OF EVIDENCE Level IV, Case Series.