Postoperative Maintenance of Sagittal Plane Positioning of the First Metatarsophalangeal Joint After Arthrodesis with an Isolated Dorsal Plate Construct: A Retrospective Review of 43 Feet.

Background: First metatarsophalangeal joint arthrodesis with isolated dorsal plating without a lag screw and without a compressive mechanism incorporated into the plate is not well studied. Although surface area for bony fusion is increased, there is concern for lower fusion rates and progressive loss of sagittal plane positioning. We present fusion rates and progressive sagittal plane deviation with isolated dorsal plate fixation.

Methods: A retrospective review was performed of 41 patients (43 feet) who underwent first metatarsophalangeal joint arthrodesis with isolated dorsal plate fixation. Patients were excluded if another form of fixation was used, if there was a compressive feature to the dorsal plate, or if a lag screw was used. Preoperative, immediate postoperative, and final postoperative radiographs were reviewed to assess radiographic alignment and fusion about the first metatarsophalangeal joint. Specific attention was placed on hallux dorsiflexion in relation to the first metatarsal. Statistical significance was set at P ≤ .05 a priori.

Results: Patients were followed for an average of 55.7 weeks. Overall union rate was 97.62%. The average time to union was 42.55 days. Reoperation rate was 4.65%, with one patient requiring revisional arthrodesis with a lag screw construct. Hallux abduction and first-second intermetatarsal angle correction reached significance (P < .00001). Hallux dorsiflexion increased by 1.05° between initial postoperative and final postoperative radiographs (P = .542).

Conclusions: Although fusion rates and progressive loss of sagittal plane position have been concerns for first metatarsophalangeal joint arthrodesis with an isolated dorsal plate construct, these results suggest this to be a stable construct without loss of positioning over time.