Why and How Often Is Revision Surgery Necessary after First Metatarsophalangeal Joint Arthrodeses? A Cohort of 120 Consecutive Cases

Abstract

Background: Little is known about the rate and reasons for revision after primary Metatarsophalangeal (MTP1) arthrodesis with the latest implants. While it is commonly assumed that nonunion accounts for most reoperations, we hypothesized that malposition is the leading cause of revision. The aim of this study was to determine the rate and reasons for revision after MTP1 arthrodesis using cup- and cone-reamers and the latest locking plate technology. Method: Between 2015 and 2017, 120 consecutive MTP1 fusions in 114 patients were performed with a low profile, pre-contoured titanium dorsal locking plate and a plantar metatarsophalangeal screw. The rate and reasons for revision within a minimum one-year follow-up period (average 16 months [12 - 26]) after index procedures were documented and analyzed. The revision was defined as any reoperation following the index procedure excluding hardware removal. Results: Seventeen of 120 feet (14%) underwent revision. Four patients developed a nonunion (3.3%) and needed revision, and 11 feet (9%) required revision for painful malposition; insufficient extension and excessive valgus accounted for the majority. Two patients required medial sesamoidectomy. No infection or wound healing problems occurred. Twelve patients requested hardware removal. Conclusions: Nonunion revision rate after MTP1 fusion with the latest locking plate technology is low. The leading cause of revision is malposition followed by nonunion. Excessive valgus and insufficient extension account for most symptomatic malposition. A recommendation of 0 - 10 degrees of valgus in the horizontal plane may contribute to diminishing revision rates; no conclusions could be drawn regarding an optimal position in the sagittal plane.