Effect of surgery for ankle osteoarthritis on locomotive syndrome

Locomotive syndrome (LS) is characterized by a decline in locomotor function due to musculoskeletal disorders. However, few studies have explored its association with ankle osteoarthritis (AOA) or surgical impact. This study evaluated LS and its improvement following corrective osteotomy (CO) or arthrodesis for AOA and compared outcomes between procedures. LS stages, ranging from 0 (healthy) to 3 (most declined), were assessed preoperatively and at 12 months postoperatively using the stand-up test (ability to rise from different heights), two-step test (maximum stride length over two strides), and GLFS-25 (self-reported locomotor function). Pre- and postoperative comparisons and group differences were analyzed, with p < 0.05 considered significant. Forty patients were included. All patients had a preoperative LS stage 1 to 3, with a prevalence of LS stage 3 of 57.5 %. At 12 months after surgery, the prevalence of LS stage 1 to 3 was 95.0 %, but the prevalence of LS stage 3 decreased to 30.0 %. At least one LS stage improved postoperatively in 19 patients (47.5 %). There was no significant difference between pre- and post-operative stand-up test results (p = 0.74), but the two-step test and GLFS-25 improved significantly postoperatively (two step: p = 0.01, GLFS-25: p < 0.001). The GLFS-25 improved significantly postoperatively in both groups (corrective osteotomy: p = 0.001, Arthrodesis: p = 0.01); however, the two-step test improved significantly postoperatively only in the corrective osteotomy group (corrective osteotomy: p = 0.02, Arthrodesis: p = 0.44). In conclusion, ankle osteoarthritis may be a factor affecting LS, and corrective osteotomy tended to be more effective in improving the two-step test.