Postoperative contracture as a major complication of surface replacement arthroplasty (SRA) remains an unresolved problem. Contracture after SRA can occur early in the postoperative period due to mechanical dysfunction, and tardy contracture where ROM declines with time postoperatively is also reported.
13 fingers with degenerative osteoarthritis and two fingers with post-traumatic arthritis where SRA was performed using volar approach were involved. Contracture was defined as limited ROM of less than 35 degrees. Cases were then categorized into two groups according to time of onset of contracture; early contracture and tardy contracture. Characteristic findings of postoperative X-rays in each contracture group were examined. Required procedures and efficacy of any further surgery was also reviewed.
Early contracture was observed in three cases, all of which suffered intra-operative fracture or fragility of the central slip insertion on the dorsal rim of the middle phalanx. This was observed in a further two cases, both of which deteriorated to tardy contracture. Tardy contracture was observed in five cases, and the average ROM was 63 degrees preoperatively, 48 degrees one year postoperatively and 21 degrees at the most recent follow-up, or at the time of the second surgery. In the three cases, development of osteophyte formation on the volar aspect of the proximal head component was observed on the follow-up X-rays. Required further surgeries were resection of the volar plate in two cases, resection of ossification in one and resection of the osteophyte in two. The results of further surgeries were mediocre in all but one case.
This study showed that intra-operative fracture or fragility of the central slip insertion was a risk factor for postoperative contracture after SRA, and that development of osteophyte formation can be a cause of deterioration in ROM of the PIP joint.