Delayed Postoperative Rehabilitation and Physical Function Recovery Following Late Open Conversion After Endovascular Aneurysm Repair

Background Late open conversion (LOC) after endovascular aneurysm repair (EVAR) is a highly invasive and technically complex procedure. However, postoperative rehabilitation progress and changes in physical function following LOC have not been sufficiently investigated. This study aimed to compare postoperative rehabilitation progress and changes in physical function between patients undergoing LOC after EVAR and those undergoing primary open surgical repair (OSR). Methods This single-center retrospective cohort study included 63 patients who underwent elective primary OSR or LOC between December 2022 and December 2025. The primary outcome was postoperative rehabilitation progress, assessed by the days to first ambulation and independent 100-m walking. Secondary outcomes were changes in physical function, including the Short Physical Performance Battery (SPPB) and six-minute walk distance (6MWD), from before surgery to hospital discharge. Changes in physical function were analyzed using two-way repeated-measures analysis of variance. Results The study included 46 patients in the primary OSR group and 17 in the LOC group. The LOC group required significantly more days to achieve first ambulation (5 (2-8) vs. 2 (2-2) days, p < 0.001) and independent 100-m walking (8 (6-13) vs. 5 (4-6) days, p < 0.001). Significant group-by-time interactions were observed for the SPPB (p = 0.004) and 6MWD (p = 0.048). At hospital discharge, the LOC group had lower SPPB scores (10.2 ± 1.8 vs. 11.4 ± 1.0 points, p = 0.001) and shorter 6MWD (288.9 ± 87.0 vs. 372.2 ± 97.9 m, p = 0.003) than the primary OSR group. Conclusions Compared with patients undergoing primary OSR, those undergoing LOC after EVAR experienced delayed postoperative rehabilitation and greater deterioration in physical function, particularly in lower-extremity physical performance and exercise capacity. These findings may reflect the combined effects of greater surgical invasiveness, procedural complexity, and differences in baseline characteristics.