Long-term clinical, functional and radiological outcomes after total arthroplasty of the first metatarsophalangeal joint in the treatment of hallux rigidus.

PURPOSE: To evaluate the long-term clinical, functional, and radiological outcomes, implant retention, and revision requirements after total arthroplasty of the first metatarsophalangeal (MTP) joint for hallux rigidus. MATERIALS AND METHODS: This retrospective single-center study included 41 patients who underwent first metatarsophalangeal joint total arthroplasty for hallux rigidus between January 2010 and December 2015 and had a minimum follow-up of ten years. Long-term clinical and functional outcomes, including the Visual Analog Scale (VAS), the American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-Interphalangeal (AOFAS Hallux-MTP-IP) score, and dorsiflexion range of motion, were analyzed exclusively in the 35 patients with retained implants who completed more than ten years of follow-up, whereas implant retention, revision rates, and radiological outcomes were assessed in the entire cohort of 41 patients. A formal time-to-event survival analysis was not performed. Outcomes at postoperative one and ten years were compared. RESULTS: The mean age was 53.7 ± 8.4 years, and the mean follow-up period was 12.8 ± 3.7 years. Mean VAS scores improved from 7.5 ± 0.8 preoperatively to 2.6 ± 0.8 at one year and 3.4 ± 0.8 at ten years. Mean AOFAS scores increased from 37.8 ± 8.8 preoperatively to 84.3 ± 9.8 at one year and remained 76.4 ± 9.0 at final follow-up. Mean dorsiflexion improved from 7.2 ± 2.2° to 24.2 ± 8.2°. At final follow-up, the implant was retained in 35 patients (85.4%), whereas six patients (14.6%) underwent arthrodesis. The most common radiological complications were osteolysis (17.1%) and malposition (14.6%). CONCLUSION: First MTP joint total arthroplasty provides durable pain relief, functional improvement, and preservation of joint motion in patients with hallux rigidus. However, complications such as osteolysis, malposition, and revision surgery should be considered, highlighting the importance of careful patient selection and long-term follow-up.