Silastic joint arthroplasty for end stage Hallux Rigidus - a joint preserving alternative

M. Sethi, R. Limaye

Aim: Osteoarthritis of the first metatarsophalangeal joint affects one in three people over the age of 65 years. Arthrodesis remains the gold standard but it has its own complications. It is associated with adjacent joint arthritis, transfer metatarsalgia and up to 10% non-union rate. The aim of this study was to analyse the outcome of double stemmed silastic joint arthroplasty (Wright-Medical, Memphis, Tennessee, USA) for end stage Hallux Rigidus.

Methods: This retrospective analysis included 117 consecutive 1st MTPJ silastic arthroplasties done between January 2016 to February 2023 for end stage Hallux rigidus. There were 77 females and 40 males with a mean age of 65 years (46-82 years). Radiological and clinical assessments were performed, and patient reported outcome measure data (PROMS) and Visual Analogue Scale (VAS) scores were collected pre and post operatively.

Results: Findings showed 99.1% survivorship following a silastic joint arthroplasty with a mean follow up of 5 years (6 months-7 years[LN1] ). The MOXFQ score improved from a mean of 81 (59.8-100) to 13 (0-57). The mean VAS scores improved from 7.2 (5-10) to 1.5 (0-7) postoperatively. Five patients were lost to follow up. Two patients developed deep infection and one required revision. The other patient with infection was lost to follow up. In total 10 patients (8.9%) developed complications, out of which 8 patients responded to simple treatments.

Conclusion: Results have shown good to excellent outcomes following a silastic arthroplasty of the first metatarsophalangeal joint for the treatment of end stage hallux rigidus. The survivorship at a mean follow- up of 5 years was 99.1%. As historically reported, we did not see any soft tissue reaction or progressive osteolysis in any of our patients. It provides comparable and predictable outcomes to joint fusion for end stage arthritis.