Age affects the perception of limb length discrepancy in patients with and without a total hip arthroplasty

The amount of lengthening or shortening that can be detected by patients before and after total hip arthroplasty has not been yet quantified. We studied the ability to detect limb length inequality in 194 patients with and without a total hip arthroplasty, match-paired for age and sex. None of the participants had clinical signs of lumbosacral pathology, spinal deformity, or fixed pelvic obliquity; and all had equal functional and actual limb length. The participants walked with shoes, with and without the addition of fixed insoles, to simulate 2.5, 5, 10 and 15 millimeters of shortening and lengthening of the tested limb. Lengthening and shortening were similarly detected. Younger individuals detected the differences better than older ones (p=0.001), and there was a significant correlation between the decade of life and the ability to detect a limb length discrepancy (r=-0.22; p=0.002). This study demonstrates that perception of limb length is affected by the age, with older individuals having less awareness of changes in limb length than younger ones. (Hip International 2004; 14: 249-53).