Clinical Outcomes for Patients with Rheumatoid Arthritis After Undergoing Total Ankle Replacement as Compared to Those with Noninflammatory Arthritis


Rheumatoid arthritis (RA) is an inflammatory condition in which the body’s immune system attacks it’s own tissues, in this case the small joints in your body. The ankle joint is commonly affected and can lead to great disability in RA patients. In the past, patients with RA who suffered from disabling ankle arthritis often underwent ankle fusion. This has led to complications including wound healing difficulties, great stiffness as there is often involvement of other small joint in the same foot and even tibial stress fracture from limited forward translation of the affected limb. Total ankle arthroplasty (replacement) has been pursued as a way to preserve hindfoot motion. A recent study aimed to investigate the intermediate-term clinical outcomes and safety of total ankle replacement in patients with RA and matched a cohort of patients with noninflammatory arthritis who underwent the same procedure.

A cohort of fifty patients with RA who underwent a total ankle replacement was identified through the Canadian Orthopaedic Foot and Ankle Society. The database was drawn from four centers across Canada. The control group consisted of fifty age-matched patients with noninflammatory arthritis who underwent the same procedure and were obtained from the same database. Besides age, these groups were matched for follow-up time and type of prosthesis. Clinical outcomes were assessed utilizing the Ankle Osteoarthritis Scale (AOS) and the quality-of-life Short Form-36 (SF-36) Health Survey Standard Version 2.0. Twelve patients with RA and one patient with noninflammatory arthritis had undergone hindfoot joint fusion prior to their replacement. Clinical outcome score analysis of the AOS pain scores demonstrated that the RA group had a higher level of pain preoperatively but improved to a pain level that was equivalent to that of the noninflammatory arthritis group after total ankle replacement. There was no significant interaction effect between treatment and rheumatoid or noninflammatory groups in regards to the AOS disability score. The physical component scores for the SF-36 demonstrated that while the health of both groups improved after total ankle replacement, the noninflammatory arthritis group demonstrated a greater mean change and significantly better physical health at final follow up. The mental component scores of the SF-36 demonstrated modest, but significant, improvements in both RA and noninflammatory arthritis groups. Revision rates were found to be 12 per cent in the RA group and 10 per cent in the noninflammatory arthritis group with a mean time to revision of four years and six and a half years respectively. In this study, one RA patient required removal of the implant secondary to deep infection while another patient suffered a superficial wound complication which required a skin graft. The RA group underwent a greater number of additional procedures to manage associated arthritis throughout the foot at the time of the replacement. While the noninflammatory arthritis group underwent a greater number of additional hindfoot procedures after total ankle arthroplasty to help protect the replacement through correcting hindfoot alignment.

Overall the authors of this study feel that total ankle replacement provides good outcomes for patient with RA in the intermediate term. While the overall pain and disability for these patients was worse preoperatively than the noninflammatory arthritis group, this did not negatively impact the outcomes after total ankle replacement.