TIBIOCALCANEAL ARTHRODESIS FOR NONBRACEABLE NEUROPATHIC ANKLE DEFORMITY

Seven patients with nonbraceable, neuropathic ankle joints have been s uccessfully treated by tibiocalcaneal arthrodesis utilizing an adolesc ent condylar blade plate, large cannulated AO screws, and a special ca ncellous allograft mixture. All patients had fragmentation and partial resorption of the talus. This procedure was considered as an alternat ive to below-knee amputation. Goals were limb salvage and limited comm unity ambulation. Criteria for proceeding with the fusion were a commi tment by the patient to 6 to 8 months of nonweightbearing ambulation, a biopsy and culture of the talus revealing no evidence of infection, and a nonbraceable deformity of the foot and ankle that would otherwis e require amputation. A toe-level Doppler index or a transcutaneous ox ygen index of greater than 0.45 was required. All patients were treate d initially in a total contact cast or bivalved total contact ankle-fo ot orthosis (AFO) until wounds and swelling were controlled and there was no erythema. Presence of an ulcer did not preclude surgery. The ar throdesis used a combination of 7.0-mm AO cannulated screws and an ado lescent condylar blade plate. A special preparation of fresh-frozen, i rradiated, cancellous allograft mixed with tobramycin and vancomycin p owder was used. All ankles fused solidly in an average of 5.2 months. No infectious complications were encountered. Two patients developed a stress fracture of the tibia at the proximal aspect of the blade plat e before use of a bivalved AFO. These healed with nonoperative treatme nt in 6 weeks. All patients were satisfied with their result at their latest follow-up (average 26.9 months). They were all ambulatory in a lined, bivalved, molded AFO without the use of an ancillary device. Wi th strong patient commitment, stringent preoperative criteria, and met iculous surgical technique, tibiocalcaneal arthrodesis can be achieved with this technique and should be added to the orthopaedist's armamen tarium of nonbraceable neuropathic ankle procedures.