Effect of Subtalar Fusion and Calcaneal Osteotomy on Function, Pain, and Gait Mechanics for Calcaneal Malunion.

BACKGROUND: Calcaneal malunion is a common complication of nonoperative management of calcaneal fracture, which leads to a disruption of the biomechanics of the lower extremity, pain, and permanent disability. Our aim was to evaluate pain, function, and gait after combined subtalar joint fusion, calcaneal osteotomy, and lateral wall exostectomy for patients with neglected calcaneal fractures with malunion. METHODS: Eighteen patients with malunited calcaneal fractures, varus deformity, and subtalar arthritis were operated upon and then followed up for 18 months. All cases were assessed clinically using the American Orthopaedic Foot & Ankle Society (AOFAS) and visual analog scale (VAS); radiologically by measuring the talar inclination, talocalcaneal and talus-first metatarsal angles, and talocalcaneal height; and biomechanically by measuring the stride duration, step width, comfortable speed, and ground reaction forces in relation to the body weight. RESULTS: A significant improvement in AOFAS (59.8 preoperatively to 80.2 after 18 months) and VAS (61.1 preoperatively to 29.4) was found. Also, our study revealed a significant improvement in the radiographic measurements including the valgus angle, the talocalcaneal angle, the talocalcaneal height, and the talar inclination angle. The gait analysis found that the maximum loading force in the push-off phase and comfortable speed yielded a significant improvement postoperatively. However, no significant differences between the preoperative data and the final follow-up in terms of the step width, stride duration, maximum peak force during loading phase, and minimum peak force during midstance phase were found. CONCLUSION: The combination of valgus calcaneal osteotomy, lateral wall exostectomy, and subtalar fusion resulted in pain reduction, improved function, and better gait. However, the limited bone stock for the graft used in the subtalar fusion made use of this technique in severely reduced height unadvisable. LEVEL OF EVIDENCE: Level IV, case series.

Foot and ankle function after tibial overlengthening.

Lengthening the tibia more than 25% of its original length can be indicated for proximal femoral deficiency, poliomyelitis, or femoral infected nonunion. Such lengthening of the tibia can adversely affect the ankle or foot shape and function. The present study aimed to assess the effect of tibial lengthening of more than 25% of its original length on the foot and ankle shape and function compared with the preoperative condition. This was a retrospective study of 13 children with severe proximal focal femoral deficiency, Aitken classification type D, who had undergone limb lengthening from June 2000 to June 2008 using Ilizarov external fixators. The techniques used in tibial lengthening included lengthening without intramedullary rodding and lengthening over a nail. The foot assessment was done preoperatively, at fixator removal, and then annually for 3 years, documenting the range of motion and deformity of the ankle and subtalar joints and big toe and the navicular height, calcaneal pitch angle, and talo-first metatarsal angle. At fixator removal, all cases showed equinocavovarus deformity, with decreased ankle, subtalar, and big toe motion. The mean American Orthopedic Foot and Ankle Society score was significantly reduced. During follow-up, the range of motion, foot deformity, and American Orthopedic Foot and Ankle Society score improved, reaching nearly to the preoperative condition by 2 years of follow-up. The results of our study have shown that tibial overlengthening has an adverse effect on foot and ankle function. This effect was reversible in the patients included in the present study. Lengthening of more than 25% can be safely done after careful discussion with the patients and their families about the probable effects of lengthening on foot and ankle function.