Non-constrained titanium-polyethylene total endoprosthesis in the treatment of hallux rigidus. A prospective clinical 2-year follow-up study.

Abstract

To evaluate the outcome in a prospective 2-year follow-up study of a non-constrained titanium-polyethylene total endoprosthesis (ReFlexion) in the treatment of hallux rigidus. Ten patients with painful hallux rigidus were treated with a non-constrained titanium-polyethylene total endoprosthesis (ReFlexion). The American Orthopaedic Foot and Ankle Society (AOFAS) scoring was used preoperatively and at follow-up. At 2-year follow-up, the AOFAS scoring shbwed 5 instances of excellent, 1 of good, 2 of fair, and 2 of poor outcome. Eight patient were subjectively satisfied and 2 dissatisfied. Five of the patients were painless, 4 had mild, occasional pain, and 1 had moderate, daily pain in the first metatarsophalangeal joint. The mean VAS was 7.6 (SD 2.0) preoperatively and 1.1 (SD 1.4) at 2-year follow-up (p < 0.001). Extension increased by a mean of 25 (13-38) degrees and flexion by a mean of 15 (2-35) degrees (p < 0.001). Eight patients had no activity limitations, while 1 had mild and 1 moderate limitations. Alignment of the metatarsophalangeal joint was good in 7 cases, but some degree of valgus malalignment was seen in 2 and symptomatic malalignment in 1. Complications included one subluxation of a prosthesis, one recurrence of severe valgus alignment and one superficial wound infection. Radiological loosening of one cementless phalangeal component was seen at follow-up. The non-constrained titanium-polyethylene total arthroplasty gave satisfactory 2-year outcome in 60% of the patients. It is an alternative treatment for hallux rigidus in low demand patients. We do not recommended it for athletes and young people, because high forces acting on the prosthesis may cause a failure.