A Retrospective Review of Psychosocial Outcomes After Microprocessor Knee Prescription

Introduction Microprocessor knees have been shown to improve gait biomechanics and to reduce the frequency of falls, but evidence of their influence on psychosocial health is limited. Study Design Retrospective analysis. Objective The aim of this study was to evaluate the change in psychosocial outcome measures when prosthetic users change from a non-microprocessor-controlled prosthetic knee (NMPK) to a microprocessor-controlled prosthetic knee (MPK). Methods Using validated outcome measures, physical and psychological attributes of 26 MPK users were analyzed using data collected at routine appointments. Baseline data were collected using NMPK limbs first, then compared with data collected 4 weeks and 6 months after initial MPK fitting. Results A significant improvement of 13.7% in Reintegration to Normal Living Index (RNLI) scores was observed after 6 months (P = 0.001). The Patient Health Questionnaire-9 (PHQ-9) demonstrated a 64.6% significant reduction in the presence of depression-like symptoms after 6 months of MPK use (P < 0.001), including four participants who previously scored highly enough to be diagnosed with major depressive disorder. Frequency of falls reduced significantly as well (P < 0.001). Increases in self-selected walking speed were seen in both the 2-minute walk and 6-minute walk tests. Conclusions Significant improvements were seen in all psychosocial outcome measures, indicating participants' psychosocial health improved with the prescription of an MPK despite a lack of clinically important improvements in parallel performance-based outcome measures. Clinical Relevance MPKs are well documented to reduce trips and falls, which is corroborated by this research. However, the psychosocial benefits of MPKs are not documented extensively; this study provides evidence of an improvement in psychological wellbeing in this cohort.