Dorsal Capsule Interpositional Arthroplasty of the Metacarpophalangeal Joint

Background: Current recommendations for osteoarthritis of the metacarpophalangeal joint (MCPJ) are confined to implant arthroplasty to preserve joint motion and provide pain relief. This study documents the median 2-year results of a novel soft tissue arthroplasty technique that interposes the dorsal capsule. Methods: A retrospective review of 10 MCPJ dorsal capsule interposition arthroplasties in 8 patients was conducted. Physical evaluation assessed MCPJ range of motion (ROM), grip strength, and pain. Outcome tests used were the Michigan Hand Outcome Score, Visual Analog Scale (VAS), and Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH). Kellgren and Lawrence Classification assessed severity of MCPJ osteoarthritis on preoperative radiographs. Results: The mean follow-up was 29 months from surgery. Average VAS was 2/10 postoperatively and average postoperative ROM improved 7 degrees. Average postoperative grip strength of the surgical hand was 30 kg. The QuickDASH average score was 24. Average Michigan Hand Questionnaire final score was 70. Patients with Kellgren Grades 2 or 3 osteoarthritis had the best QuickDASH and Michigan Hand Outcome scores. All patients working before surgery returned to work. No patient required a second surgery. Conclusion: This technique of dorsal capsule interposition arthroplasty provides a viable surgical option for isolated degenerative or traumatic arthritis of the MCPJ at an average follow-up of 2 years. Pain relief was most reliably provided in patients with less severe radiograph findings. The advantages of this procedure include preservation of bony anatomy, collateral ligaments, and volar plate to not preclude later implant arthroplasty.