Gait asymmetry in patients with limb-length inequality.

One of the problems facing the clinician is the differentiation between functional and structural limb-length inequality. This study investigated 20 subjects (mean age, 9.0 +/- 3.9 years) with documented limb-length inequalities to determine the magnitude of discrepancies that result in gait abnormalities. The subjects were asked to walk on an 8-m walkway at a self-selected free pace. The contact time, first and second force peaks, and loading and unloading rates of the vertical ground-reaction force were measured for both limbs. These parameters were predictive for quantification of gait asymmetry. The asymmetry of these parameters increased as the limb-length inequality increased. In general, a limb-length inequality > 2.0 cm (3.7%) resulted in gait asymmetry that was greater than that observed in the normal population. However, the amount of asymmetry varied for each individual. A static examination can document an anatomic deformity, but this deformity may be compensated for by functional adaptations. An analysis of the patient's gait should be performed to identify asymmetries during ambulation. Dynamic gait findings, such as demonstrated in this study, are needed to support static measurements.