Conversion of First Metatarsal-Phalangeal Joint Arthrodesis to Arthroplasty: A Case Report

Introduction: Arthrodesis remains the gold standard for most first metatarsal-phalangeal joint (1MTPJ) pathologic conditions due to its high patient satisfaction, low complication rates, and consistent data. 1MTPJ arthroplasty remains a pursued procedure given the advantages described above, but the literature remains complicated and controversial as a primary surgical treatment. To the authors’ knowledge, there is no prior report describing utilization of arthroplasty as an approach to managing clinical failure of a successful fusion in the setting of a technically successful procedure without a post-operative complication. Case Report: We present a case report of a 70-year-old female patient who underwent a successful 1MTPJ arthrodesis for hallux valgus and hallux rigidus and extensive tarsometatarsal arthrodesis for midfoot arthritis. Although the patient had radiographic evidence of successful fusion and had no surgical complications, she presented with dissatisfaction and pain due to functional limitations imposed by the procedure sequelae. The patient was diagnosed with right foot hallux interphalangeus with painful retained hardware. Conservative management failed to improve dissatisfaction or symptoms, and the patient opted for surgical takedown of her fusion with conversion to metatarsal-phalangeal joint arthroplasty, removal of hardware, and second toe proximal phalanx exostectomy. A stepwise surgical technique is described for the procedure, which was successful in addressing the patient’s perceived clinical failure. Conclusion: Our case report describes a rare example of a patient who did not tolerate successful arthrodesis of the 1MTPJ, which was successfully revised to recreate the joint using a decellularized dermal allograft. The procedure resulted in fantastic patient satisfaction and long-term outcomes. This case report highlights a potential salvage option for patients who do not tolerate a 1MTPJ arthrodesis. Keywords: Case report, first metatarsal-phalangeal joint fusion, revision arthroplasty, interpositional arthroplasty, hallux interphalangeus.