A retrospective review of psychosocial outcomes after microprocessor knee prescription

Study Design: Retrospective Analysis 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. Objective: 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 analysed using data collected at routine appointments. Baseline data were collected using NMPK limbs first then compared to data collected four weeks and six months following initial MPK fitting. Results: A significant improvement of 13.7% in Reintegration to Normal Living Index (RNLI) scores was observed after six months (p=0.001). The PHQ-9 demonstrated a 64.6% significant reduction in the presence of depression-like symptoms after six 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.