Pyrocarbon interposition (PyroDisk) implant for trapeziometacarpal osteoarthritis: minimum 5-year follow-up.

PURPOSE

To report outcomes after a minimum of 5 years following pyrocarbon interposition (PyroDisk) trapeziometacarpal joint implant for osteoarthritis at a single center.

METHODS

We retrospectively reviewed the midterm clinical and radiological outcomes of 19 patients who had a pyrocarbon interposition implant (PyroDisk; Integra Life Sciences, Plainsboro, NJ) arthroplasty. The rate and causes of repeat surgeries, revisions, and complications were examined.

RESULTS

The mean follow-up period was 68 months. Patient satisfaction was high. The mobility of the operated thumb was restored to a range of motion comparable with that of the contralateral thumb. Grip strength improved by 26%. Overall function, according to the Quick Disabilities of the Arm, Shoulder, and Hand score, showed an average improvement of 71 to 20. Pain decreased by 78% according to the numerical rating scale. Radiological evaluation using a modification of the system described by Herren revealed progression of the periprosthetic lucency (grade I-II) of the implant after 5 years in 5 of 19 (26%) patients. Progression of lucency did not predict implant loosening or failure at 5 years. Two patients had symptomatic instability that required revision. No dislocations occurred. The 5-year survival of the prosthesis was 90%.

CONCLUSIONS

The PyroDisk implant for treating advanced trapeziometacarpal arthritis did not demonstrate superiority over published outcome data of trapeziectomy with or without ligament reconstruction and tendon interposition.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.