Stepping Up: A Functional Ambulation Study Across Multiple Levels of Non-Traumatic Amputation

Category: Other Introduction/Purpose: The level of amputation for patients with non-traumatic foot pathologies is a complex decision that limb salvage surgeons face, with ambulation playing a crucial role in the quality of life and long-term survival of amputees. In recent years, gait sensors have been used to access ambulation. This study investigates functional outcomes of digit, ray, transmetarsal (TMA), and below-knee amputations (BKA) using wearable gait sensors. Methods: Between December 2021 and January 2024, adult patients who were able to ambulate unassisted, without experiencing pain, and without an open wound or lower extremity surgery in the preceding three months, were selected for participation. Inclusion was voluntary and offered to all patients who presented to the wound care center for a period of 3 years. Out of 451 patients, 77 patients who had undergone amputations at levels including digit amputation, ray resection, TMA, or BKA, were included in this analysis. Patient characteristics, preoperative factors, and surgical history were collected. Participants completed a standardized assessment protocol using wearable gait sensors. This involved completing a 120-second walk test at a self-selected pace. The data collected from the sensors were analyzed using the Motility Lab software, with statistical significance set at p < 0.05. Results: A total of 77 patients were included for analysis, comprising 30 (38.9%) digit, 12 ray (15.6%), 12 TMA (15.6%), and 23 BKA (29.9%). The average age (61.3 1.19 years), body mass index (30.8 0.71 kg/m 2 ), and Charlson Comorbidity Index (4.9 0.2) did not differ between groups. Proportion of smokers (n=30, 34.8%), diabetes mellitus type II (n=54, 62.8%), chronic kidney disease (n=24, 29.1%), end stage renal disease (n=7, 8.1%) was similar across all four groups. There were no differences in gait speed (0.80 0.02 m/s, p=0.414), elevation mid-swing (1.62 0.14 cm, p=0.063), step duration (0.63 0.01s, p=0.066), cadence (96.2 1.2 steps/min, p=0.434), single limb support (34.4 0.3%, p=0.185), double limb support (29.2 0.6%, p=0.089), and stride length (0.97 0.02 m, p=0.225) across level of amputations. Conclusion: Our study shows comparable ambulatory function across all levels of amputation. This may highlight the importance of selecting the right amputation per patient, multidisciplinary limb salvage, and improvements in wearable aids. We encourage other large limb salvage centers to utilize wearable sensors to assess functionality of non-traumatic amputations.