The medial column Synthes Midfoot Fusion Bolt is associated with unacceptable rates of failure in corrective fusion for Charcot deformity

Abstract

Charcot neuro-osteoarthropathy (CN) of the midfoot presents a major reconstructive challenge for the foot and ankle surgeon. The Synthes 6 mm Midfoot Fusion Bolt is both designed and recommended for patients who have a deformity of the medial column of the foot due to CN. We present the results from the first nine patients (ten feet) on which we attempted to perform fusion of the medial column using this bolt. Six feet had concurrent hindfoot fusion using a retrograde nail. Satisfactory correction of deformity of the medial column was achieved in all patients. The mean correction of calcaneal pitch was from 6° (-15° to +18°) pre-operatively to 16° (7° to 23°) post-operatively; the mean Meary angle from 26° (3° to 46°) to 1° (1° to 2°); and the mean talometatarsal angle on dorsoplantar radiographs from 27° (1° to 48°) to 1° (1° to 3°). However, in all but two feet, at least one joint failed to fuse. The bolt migrated in six feet, all of which showed progressive radiographic osteolysis, which was considered to indicate loosening. Four of these feet have undergone a revision procedure, with good radiological evidence of fusion. The medial column bolt provided satisfactory correction of the deformity but failed to provide adequate fixation for fusion in CN deformities in the foot. In its present form, we cannot recommend the routine use of this bolt.

Charcot Neuropathic Arthropathy of the Foot: A Literature Review and Single-Center Experience

“…When the resection is done and the reposition is finished we use them to fix intramedullary both the medial and lateral columns and subsequently apply plaster cast fixation. By using such a technique we eliminate the disadvantages of using the plates as mentioned above and we did not observe any osseous healing failure reporting by some authors [ 43 , 44 ].…”

Charcot hindfoot deformity reconstruction using a hindfoot nail- surgical technique

“…The principle of fixation in Charcot hindfoot reconstruction using internal fixation is-durable long segment rigid fixation with optimal bone opposition. 8 After deformity correction, the ankle and subtalar joints are held in optimal position by inserting 2 mm Kirshner wires. The entry point of the hindfoot nail guide wire is determined by placing a long guide wire over the leg and foot along the axis of tibia in the coronal and sagittal planes and screening under fluoroscopy in the anteroposterior and lateral views respectively.…”

Predictors of metalwork failure and nonunion after hindfoot Charcot reconstruction

“…Additional rigidity to the fixation construct improves the bone fusion rates and hence, in our unit, we follow the fixation principle of durable long-segment rigid fixation with optimal bone opposition for all Charcot foot reconstructions, including those featured in this series. 15 Charcot hindfoot deformities are often associated with significant bone loss and soft-tissue imbalance due to contractures and muscle weakness. Rigid fixation construct with an IMN alone is difficult to achieve, as the distal locking screw holes often do not match the bone fragments following the deformity correction.…”