Improvement in gait parameters after lengthening for the treatment of limb-length discrepancy

Background Patients who have limb-length discrepancy demonstrate an altered gait pattern or a limp. The purpose of this prospective study was to compa re the objective gait parameters for the shorter lower limb with those for the longer lower limb before and after lengthening and to compare these dat a with those for a group of twenty subjects who had no limb-length discrepa ncy. Methods: Eighteen patients had equalization of limb length to within one ce ntimeter. We analyzed the stance time, the second peak of the vertical grou nd-reaction-force vector, and the rate of loading with use of two force-pla tes arranged in a series. Results: The difference in the mean stance times between the shorter and lo nger limbs before lengthening was 12 percent, whereas that after lengthenin g was 2.4 percent; the difference between the values before and after lengt hening was significant (p < 0.001), The difference in the stance times betw een the limbs of the patients who did not have limb-length discrepancy was 2 percent, Preoperatively, the mean second peak was 104 percent of body wei ght for the shorter limb compared with 116 percent for the longer limb; thi s difference was significant (p < 0.001). After lengthening, the mean secon d peak for the shorter limb increased to 113 percent of body weight. The di fference in the means for the second peak before and after lengthening was significant (p < 0.001), With the numbers available, no significant differe nce was detected in the means for the second peak between the shorter and l onger limbs after lengthening (p = 0.12). Conclusions: This study shows that lengthening of the shorter limb of patie nts who have limb-length discrepancy can normalize symmetry of quantifiable stance parameters and eliminate a limp.