Trapeziectomy with Interpositional Arthroplasty using Acellular Dermal Matrix: Description of Technique and Early Outcomes

BACKGROUND: Trapeziectomy with interpositional arthroplasty using Repriza acellular dermal matrix is a novel technique to treat primary and secondary carpometacarpal joint arthritis. Early studies with nonautograft interposition indicate promising post-trapeziectomy space maintenance with results similar to ligament reconstruction with tendon interposition, without the potential risks and increased operating time of harvesting a tendon autograft. METHODS: Eleven patients in a retrospective cohort were followed for a minimum of 6 weeks (mean, 12). Subjective and objective data were collected to assess pain, subjective improvement of symptoms, radiographic measurements of first metacarpal subsidence, key pinch strength, grip strength, and range of motion. RESULTS: Early outcomes in our cohort compare favorably to other treatment series. On average, patients received a significant pain reduction of 63%, with 36% of patients admitting to complete pain resolution. One hundred percentage of patients admitted to overall subjective improvement in symptoms. Ninety-one percentage of patients achieved postoperative opposition of the thumb and fifth digit. Comparison with preoperative x-rays showed mean thumb metacarpal subsidence of 27%. Zigzag deformity and extra-articular acellular dermal matrix migration, due to lack of patient compliance with splint, were observed complications. Only 8.3% subsidence was observed with an impressive 45% pain reduction, in a salvage patient after revision surgery for a NuGrip implant. CONCLUSIONS: In conclusion, this is a safe and effective primary or salvage technique for Eaton grades III and IV thumb carpometacarpal arthritis with a mean subsidence within the range observed with ligament reconstruction with or without tendon interposition. Long-term study with a larger sample size is needed to investigate this technique further.