Introduction Fracture dislocation of the midtarsus with subsequent collapse of the longitudinal arch, dislocation of the forefoot and development of the rocker-bottom deformity is a significant complication of the neuropathic foot. Bony deformity and lack of protective sensation may lead to plantar ulceration, infection and amputation. Surgical reconstruction entails reduction of the dislocation and restoration of the alignment of the foot. Fixation of the arthrodesis may be challenging due to bony dissolution, fragmentation and osteoporosis which accompany the Charcot process. The purpose of the the current study is to describe the technique and review the clincial results of midtarsal arthrodesis with intamedullary axial screw fixation used to treat Charcot midfoot collapse.
Methods A retrospective study of 12 patients undergoing surgical reconstruction and arthrodesis of Charot midfoot deformity was done. Long intramedullary screws were applied antegrade or retrograde to bridge the apex of the deformity after the area had been prepared for arthrodesis through bony resection or osteotomy. Axial screws are applied such that the head or shaft of the screw gained purchase in the intramedullary canal of two or more metatarsal bones. Compression of the arthrodesis bed was achieved by tightening the screws. Radiographic measurements were taken pre-operatively, immediately post-operatively and at the last follow-up to assess the amount of durability of the correction achieved.
Results Patients were evaluated clincally and radiographically at an average of 35 month follow-up (5 to 144 months). Bony union was achieved in 83% of patients, at an average of 5.3 months. All patients returned to functional ambulatory status within seven months. The talar-first metatarsal angles in the anterior and lateral planes, talar declination angle and calcaneal-fifth metatarsal angle were all corrected to near normal values following the surgery and showed no significant collapse between immediate post-op and final follow-up. The amount of dorsal displacement of the medial column was reduced to normal values and showed no significant recurrence at final follow-up. There were no recurrent plantar ulcerations. Hardware failure occurred in one patient who was unable to comply with weight bearing restrictions and significant soft tissue complications were encountered.
Conclusions Surgical correction of Charcot midfoot collapse with midfoot osteotomy and arthrodesis utilizing multiple large-diameter intramedullary axial screws which span the area of dissolution provides an adequate construct to achieve arthrodesis and maintain alignment and reduction of the deformity.
In relation to the conduct of this study, one or more of the authors has received, or is likely to receive direct material benefits.
The abstracts were prepared by Mr Jerzy Sikorski. Correspondence should be addressed to him at the Australian Orthopaedic Association, Ground Floor, William Bland Centre, 229 Macquarie Street, Sydney NSW 2000, Australia.