There is controversy regarding the timing for surgical reconstruction of metacarpophalangeal joint deformities in patients with rheumatoid arthritis. The aim of this study was to determine whether patients with more severe ulnar drift and extensor lag deformities have worse outcomes after silicone metacarpophalangeal joint arthroplasty when compared with patients who have less severe deformities.
Seventy patients with rheumatoid arthritis and MCP deformity were recruited in a three-center prospective study. Inclusion criteria consisted of a combined metacarpophalangeal joint ulnar drift and extensor lag greater than 50 degrees. Patients were categorized into two groups based on degrees of deformity: less than 100 degrees or greater than or equal to 100 degrees and were reconstructed with MCP silicone arthroplasty. Outcomes were measured at 6 months and 1 year post-operatively.
The results indicate that there was no difference in outcomes at the 1-year follow-up between the two groups, after controlling for age, gender, and baseline values. The authors conclude that rheumatoid arthritis patients with more severe metacarpophalangeal joint diseases will attain similarly good outcomes after reconstruction when compared with those with less severe deformities.
This is the first prospective outcomes study for silicone MCP arthroplasty. This well designed study provides level-2 evidence that patients with more severe MCP deformity will attain similarly good outcomes after reconstruction and challenges the commonly held belief that silicone MCP arthroplasty produces better outcomes if the deformities are less severe. However, one needs to consider that over the long-term, patients with more severe preoperative deformity may have more rapid recurrence of deformity. The planned 3-year follow-up to this report will shed more light on this possibility.