Long-term Survival of the TOEFIT Plus First-Metatarsophalangeal Joint Replacement for End-Stage Hallux Rigidus.

BACKGROUND

End-stage hallux rigidus is currently being treated by total joint arthrodesis rather than arthroplasty more commonly. However, there is an advancing number of joint prosthesis being employed either as hemiarthroplasty or total joint replacement. One such total joint replacement is the ToeFit Plus joint.

METHODS

A retrospective cohort study over 20 years was undertaken to assess functional outcomes. Seventy total joint replacements were performed between 2006 and 2013. Fifty-seven patients (46 females, 11 males), mean age 62.1 years (range 42-82). Thirteen patients had bilateral replacements. Mean follow-up was 98.2 months (range 13-216, SD 61.3). Survival analysis used Kaplan-Meier methodology with best-case (excluding lost to follow-up) and worst-case (assuming all lost to follow-up were failures) scenarios.

RESULTS

Mean Manchester-Oxford Foot Questionnaire score at the latest follow-up telephone consultation was 7.4 (range 0-59, SD 14). Twelve of 70 joints were revised to arthrodesis because of phalangeal component loosening, with 24 joints lost to follow-up. Best-case scenario showed 81% survival at mean 11.0 years, whereas worst-case scenario showed only 48.2% survival. The mean age of patients who had revision surgery was 62.5 years (range 51-73, SD 6.9). The mean age for nonrevised patients was 62.0 years (range 42-82, SD 9.0), with no significant correlation between patients' age and the implant longevity or revision. In the first 5 years following TJR, there was a 15% chance of revision.ConclusionRevision was mainly caused by phalangeal component loosening. Even in the best-case scenario, the 19% revision rate at 10 years is concerning, but the potential 52% failure rate in worst-case analysis is unacceptably high. We recommend discontinuing the use of the ToeFit Plus arthroplasty.