Gait analysis and muscle strength in children with congenital pseudarthrosis of the tibia: the effect of treatment.

Twelve patients with healed congenital pseudarthrosis of the tibia underwent gait analysis and muscle strength testing to determine the functional result of treatment. Six children younger than 4 years of age presented with pseudarthroses (early onset), and six children first fractured at older than 4 years of age (delayed onset). Four children with amputations as final treatment for congenital pseudarthrosis were studied for comparison. The early-onset group had undergone an average of 4.2 surgeries and all required transankle fixation. The delayed-onset group had undergone an average of 1.5 surgeries, with one child requiring fixation across the ankle. Lack of ankle push-off and foot drop occurred in the early-onset group. Terminal stance phase ankle power generation was greatly diminished in the early-onset group. Total mechanical work performed by the affected limb, when compared to the uninvolved contralateral limb, was symmetric in delayed-onset patients and reduced by 68% in early-onset patients and by 85% in amputees. Gastrocsoleus strength was reduced by 40%. Gait and muscle strength of patients with "healed" congenital pseudarthrosis of the tibia are markedly disturbed. Early onset of disease, early surgery, and transankle fixation lead to an inefficient gait comparable to that of amputees.