Background: Surface replacement arthroplasty (SRA) through a volar approach for the proximal interphalangeal (PIP) joint can preserve the integrity of the extensor tendon, which allows early range of motion (ROM) exercise postoperatively. However, a few reports have shown that the PIP ROM tends to decline with longer follow-up. The goal of this study is to assess the results of at least 5 years of follow-up of SRA through a volar approach and also to investigate the cause of deterioration of ROM with time after SRA through this approach. Methods: Eleven fingers with degenerative osteoarthritis that underwent SRA through the volar approach were examined. ROM of the PIP joint preoperation, 1 year after the surgery, and at final follow-up was measured and statistically analyzed. Also, the relationship between PIP ROM and the osteophyte developed postoperatively was examined. Results: The average follow-up period was 7.3 years. The average PIP ROM of the PIP joints was 52.3° preoperatively, 54.1° at 1 year postoperatively, and 31.1° at the final follow-up. PIP ROM at the final follow-up was significantly decreased compared with that preoperatively or at 1 year postoperatively. Also, the development of an osteophyte was negatively correlated with the ROM of the PIP joint at the final follow-up. Conclusions: PIP ROM after SRA through a volar approach has the tendency to deteriorate with a longer follow-up. Development of an osteophyte is considered to be a main risk factor of deterioration in the cases of SRA through a volar approach.
Background: Surface replacement arthroplasty (SRA) through a volar approach for the proximal interphalangeal (PIP) joint can preserve the integrity of the extensor tendon, which allows early range of motion (ROM) exercise postoperatively. However, a few reports have shown that the PIP ROM tends to decline with longer follow-up. The goal of this study is to assess the results of at least 5 years of follow-up of SRA through a volar approach and also to investigate the cause of deterioration of ROM with time after SRA through this approach. Methods: Eleven fingers with degenerative osteoarthritis that underwent SRA through the volar approach were examined. ROM of the PIP joint preoperation, 1 year after the surgery, and at final follow-up was measured and statistically analyzed. Also, the relationship between PIP ROM and the osteophyte developed postoperatively was examined. Results: The average follow-up period was 7.3 years. The average PIP ROM of the PIP joints was 52.3° preoperatively, 54.1° at 1 year postoperatively, and 31.1° at the final follow-up. PIP ROM at the final follow-up was significantly decreased compared with that preoperatively or at 1 year postoperatively. Also, the development of an osteophyte was negatively correlated with the ROM of the PIP joint at the final follow-up. Conclusions: PIP ROM after SRA through a volar approach has the tendency to deteriorate with a longer follow-up. Development of an osteophyte is considered to be a main risk factor of deterioration in the cases of SRA through a volar approach.