The Value of Prosthetic Rehabilitation for Current and Potential Lower Limb Prosthesis Users
Abstract
The goal of this dissertation is to inform clinicians, researchers and policy makers of the potential value of prosthesis intervention for individuals who experience a lower limb amputation. In addition, this dissertation supports the call for more studies of high methodological quality to provide evidence of the functional and economic value associated with prostheses intervention post lower limb amputation. The second chapter (study 1) measured the time to prosthesis receipt for based on different demographic (e.g., amputation level and sex) and personal health factors (e.g., diabetes or vascular disease and age) using administrative claims data. Kaplan-Meir method and log-rank tests were used to examine overall time to prosthesis receipt following lower limb amputation surgery by amputation level (below-the-knee versus above-the-knee), sex, diabetes or vascular disease status, and region of care. Multivariable cox proportional hazard models were fit to assess the risk of prosthesis receipt after amputation. Patients without diabetes/vascular disease had a significantly longer time to prosthesis receipt than patients with diabetes/vascular disease, and those with a below-the-knee amputation had a higher risk of receiving a prosthesis earlier than those with above-the-knee amputations, after adjusting for covariates. The third and fourth chapters (studies 2 and 3) investigated the cost and healthcare utilization of prosthesis receipt stratified by time from surgery up to 12 months post-amputation (strata post-amputation by month: 0-3, 4-6, 7-9, 10-12, or no prosthesis) using administrative claims data. The adjusted analysis was performed using general linear modeling with log transformed cost and logistic regression models were used to assess healthcare utilization measured by emergency department use. Healthcare costs and utilization were reduced for those who received a prosthesis earlier (i.e., between 0 to 3 months) compared to those who did not receive a prosthesis within 12 months of amputation surgery. The fifth chapter (study 4) assessed the relationship between injurious falls and self-perceived functional mobility. Multivariable logistic regression was applied to a cross-sectional sample using clinical outcomes data. Patients with lower functional mobility scores had increased odds of experiencing an injurious fall as compared to those with higher functional mobility. The results from these four studies add to the body of literature on the economic impact of a lower limb prosthesis for potential (new patients with lower limb amputation) and current prosthesis users. Implications of study findings support the need for further exploration of clinical and potentially modifiable personal health factors in relation to prosthesis receipt and use. Study findings underscore the economic benefit of early prosthesis provision in terms of cost and healthcare utilization by emergency department use and measured by adverse events such as injurious falls. For those who are currently using a prosthesis, maintaining and improving mobility may help to reduce the burden and risk of injurious falls.