MUSCULAR STRENGTH AFTER CALLOTASIS LIMB LENGTHENING

Seven patients (average age, 9.2 years; range, 7.6-10.6 years) underwe nt callotasis lengthening of a congenital short femur. The isometric v oluntary contraction strength of the knee extensor muscles was measure d for each leg immediately before and at 6-month intervals for 2 years , starting from 2 months after the fixator was removed. The normal sid e was always stronger, even when strength was standardized for an anth ropometric estimate of the thigh muscle and bone cross-sectional areas . The increase in strength was correlated with the increase in limb si ze, both in the normal and in the lengthened limb. Although leg length discrepancy was equalized by the end of the procedure, the functional characteristics of the lengthened limb remained impaired for a signif icant time.