Arthrodesis as Salvage for Failed Metacarpophalangeal Arthroplasty.

Background: Surgical management of failed metacarpophalangeal (MCP) arthroplasties includes revision arthroplasty and arthrodesis. The purpose of this study was to review the indications and outcomes of arthrodesis as a salvage procedure for failed MCP arthroplasties.

Methods: This was a retrospective cohort study of all patients undergoing salvage MCP arthrodesis at a single institution from 1990 to 2020. Patient charts were reviewed for patient demographics, indication for salvage, surgical technique, revision rate, and time to radiographic union. Patient-reported outcomes, including the Michigan Hand Outcomes Questionnaire and an MCP-specific questionnaire detailing pain, functional, appearance, and patient satisfaction, were also collected.

Results: Eleven digits in 9 patients (6 women, 3 men, median age of 66) with median 36-month follow-up were included. The majority (91%) of patients also had concomitant soft tissue deformities, including joint contractures, extension lag, and collateral ligament insufficiency. The overall revision rate following arthrodesis was 45% with 3 digits requiring one revision each, and 2 digits undergoing 3 revisions. The overall union rate was 91% with median time to union of 4 months from most recent arthrodesis. Patient-reported outcomes obtained from 4 patients demonstrated improvements in pain and function.

Conclusion: Despite a high revision rate of 45%, salvage MCP arthrodesis following arthroplasty has a high eventual union rate of 91% and is associated with improved pain and function based on 4 patients' experiences. Arthrodesis as a salvage procedure for failed MCP arthroplasties should be considered in patients with persistent joint instability and functionally limiting soft tissue deformities.