Total Arthroplasty of the Metatarsophalangeal Joint of the Hallux
Published online on March 15, 2016
Abstract
The current gold standard in the treatment of severe hallux rigidus is arthrodesis of the first metatarsophalangeal (MTP-I) joint. We present the results of a new 3-component MTP-I prosthesis. We determined (1) the intraoperative and perioperative complications; (2) survivorship of prosthesis components and rate of secondary surgeries for any reason; (3) prosthetic component stability and radiographic alignment; (4) the degree of pain relief; and (5) the midterm functional outcomes including radiographic range of motion (ROM).
From 2008 to 2010, we prospectively included 29 MTP-I prostheses in 25 patients. The average age of the patients was 63.1 years (range, 48-87 years). The average follow-up was 49.5 months (range, 36-62 months). We observed complications and reoperations. A visual analog scale for pain and the American Orthopaedic Foot & Ankle Society (AOFAS) forefoot score were obtained pre- and postoperation. Component stability and alignment were assessed using weight-bearing radiographs. Fluoroscopy was used to determine radiographic MTP-I ROM.
Seven (24.1%) patients underwent 1 or more secondary surgeries. Four cases (13.7%) eventually had a conversion to MTP-I arthrodesis. Two patients (3 cases) died from causes not related to the procedure. This left 22 feet in 19 patients for final follow-up. All but 3 remaining prostheses showed stable osteointegration and no migration, but MTP-I alignment showed high variability. The average pain score decreased from 5.9 (range, 3-9) to 1.2 (range, 0-5). The average AOFAS forefoot score increased from 55 (range, 0-80) to 83.5 (range, 58-95). Range of motion initially increased from 37.8 degrees (range, 0-60 degrees) to 88.6 degrees (range, 45-125 degrees) intraoperatively and decreased to 29.0 degrees (range, 11-52 degrees) at latest follow-up.
Our data suggest that total arthroplasty of MTP-I leads to a high amount of revision surgeries, but the remaining patients had significant pain relief at midterm follow-up. However, we observed high variability regarding the prosthesis component alignment and poor range of motion.
Level IV, prospective cohort study.