Bone growth after lengthening of the lower limb in children.

Femoral and tibial growth was studied in 6 children undergoing a femoral lengthening and 28 children a tibial lengthening. Growth of both femurs and tibiae was evaluated for 3 years both before and after the procedure. No significant growth disturbance was noted in femoral lengthenings of 14%. However, growth variations were constant after tibial lengthening of 18% on the average and could be correlated to the amount of lengthening. The consequences of these changes are limited in terms of final limb length because overgrowth of the femur often compensates for growth retardation of the tibia when tibial lengthening is less than 18%. Experimental and clinical studies assert that lengthenings of more than 30% can result in significant and definite growth retardation of the lengthened bone.