Press-fit bone-anchored prosthesis: A prospective before-after study with one-year follow-up of patients with a lower extremity amputation

Background: Socket-related problems are a common problem in patients with a lower extremity amputation resulting in limited prosthesis use and decreased health-related quality of life (HRQoL). Press-fit bone-anchored prostheses (BAPs) are a possible solution for these patients. Aim: The aim of this study was to describe changes in function-, activity-, HRQoL- and satisfaction-level over time compared to baseline. Methods: This is a prospective before-after study with follow-ups at six- and twelve-months after surgery and one baseline assessment. Adults with a lower extremity amputation suffering from socket-related problems who received a press-fit BAP between May 2014 and September 2015 were included. The outcome measures were: a) function-level defined as gait quality, hip abductor strength, prosthetic use and back pain; b) activity-level defined as mobility level and walking ability; c) HRQoL-level; d) satisfaction-level regarding prosthesis comfort. Results: All 29 potentially eligible patients (17 men) were included in the study (median age: 56 year, range: 28-70 year), of these patients was 24% wheelchair-bound. The six- and twelve-months follow-up visits were completed for 28 and 17 patients, respectively. Relative to baseline, we found on function-level no significant change of gait quality and back pain, but hip abductor strength in both limbs increased significantly (six-months: 17-27%; twelve-months: 17-34%) and prosthesis wearing time increased significantly (six-months: 30%; twelve-months: 36%). On activity-level, the mobility level increased at both follow-ups relative to baseline. The change at twelve-months follow-up (24%) relative to baseline was statistically significant. At both follow-ups, none of the patients was wheelchair-bounded. Patient-reported walking ability increased significantly (six-months: 219%; twelve-months: 243%), the physical performance measurement revealed no change in walking ability relative to baseline. HRQoL-level increased significantly (six-months: 22%; twelve-months: 26%) relative to baseline. Satisfaction-level regarding prosthesis comfort increased significantly (31%) at both follow-ups relative to baseline. Conclusion: The influence of BAP surgery in combination with rehabilitation was in particular positive on activity-, HRQoL- and satisfaction-level in patients with socket-related problems. Clinical Relevance: Patient-reported outcomes changed positively, in particular, and to a lesser extent, the objective tests. One obvious health benefits of the described intervention is reduction of wheelchair-boundedness to 0% at both follow-ups