First Metatarsophalangeal Joint-Preserving Surgery Is Effective for Forefoot Deformity With Moderate to Severe Joint Destruction in Rheumatoid Arthritis.

Background: The study compares the clinical outcomes of first metatarsophalangeal (MTP) joint fusion vs joint-preserving surgery in rheumatoid arthritis (RA) patients with severe forefoot deformities.

Methods: This single-center retrospective study at Kyushu University Hospital reviewed RA patients who underwent either first MTP joint arthrodesis or joint-preserving surgery for hallux valgus (HV) deformity between January 2008 and December 2022. A total of 103 feet (73 cases) were analyzed, with 75 feet (58 cases) showing radiographic bone destruction of Larsen grade 3 or higher. One foot underwent resection arthroplasty, so ultimately 74 feet in 57 cases were evaluated. Surgical procedures included joint-preserving biplane osteotomy or arthrodesis with crossed screws. Clinical outcomes were measured using the Japanese Society for Surgery of the Foot (JSSF) Hallux scale, whereas radiographic assessments included HV angle (HVA). Propensity score matching was used to minimize bias when comparing postoperative outcomes between the arthrodesis and joint-preserving surgery groups.

Results: This study analyzed 74 feet undergoing either arthrodesis (27 feet) or joint-preserving surgery (47 feet) for HV. Patients in the 2 groups showed similar demographic and clinical characteristics except with respect to length of follow-up, which was greater in the arthrodesis group (5.1 ± 2.6 years vs 2.4 ± 2.0 years, P < .01) than the joint-preserving group. In the arthrodesis group, all patients underwent resection arthroplasty on the second to fifth toes. The joint-preserving group included first MTP joint surgery alone (n = 5) and first MTP joint and lesser MTP joint surgeries (resection arthroplasty, n = 29; joint-preserving surgery, n = 13). Functional scores significantly improved in both groups, with first metatarsophalangeal joint-preserving surgery yielding better postoperative outcomes. In cases of deformity recurrence, the recurrent cases exhibited greater immediate postsurgical HVA, but other foot function outcomes remained similar at the end of follow-up.

Conclusion: Joint-preserving surgery for advanced rheumatoid forefoot deformity showed better functional improvement than arthrodesis using the propensity score matching and comparable clinical outcomes, highlighting it as a potential treatment option for severe joint destruction.

Level of evidence: Level Ⅳ, retrospective study.