Functional outcomes of people with lower limb amputation following inpatient rehabilitation

Abstract

Amputation of a limb has significant consequences for an individual and the healthcare system. Lower limb amputations in Australia are most commonly due to dysvascular conditions such as diabetes and peripheral vascular disease. With risk factors increasing for dysvascular disease, lower limb amputations are similarly expected to increase, compounded by an ageing population.Despite growing interest in amputation management and outcomes, many areas remain unexplored by research in the field. This doctoral research program incorporates five studies (five papers) with the overall aims to: 1) investigate discharge outcomes for people with lower limb amputation over time; 2) compare patient outcomes according to amputation aetiology; 3) determine relationships between prosthetic walking speed and function; 4) identify factors associated with prosthetic walking prescription; and 5) explore barriers and enablers experienced when walking in the community with a prosthesis.Study 1 (Paper 1) investigated the characteristics and discharge outcomes of people with lower limb amputation (n=425) across a seven-year period. Total numbers of people with lower limb amputation did not change, but the proportion of people with lower limb amputation with nonvascular aetiology increased over time. Over the study period, patients’ functional capacity decreased at admission and discharge, and prosthetic prescription rates reduced. This study provides valuable insight into characteristics of patients with lower limb amputation at admission to, and discharge from, subacute inpatient rehabilitation.Study 2 (Paper 2) compared characteristics and discharge outcomes according to aetiology of amputation (that is, dysvascular vs nonvascular) in the same sample (n=425). Individuals with dysvascular amputation were older and had lower functional capacity at admission and discharge. Those with nonvascular amputations had higher levels of employment prior to amputation and were more likely to be prescribed a prosthesis by discharge. This study contributes important information about how aetiology influences functional outcomes.Study 3 (Paper 3) investigated relationships between prosthetic gait speed and patient characteristics including prosthetic potential (K-level) and function (FIM-Motor) of 110 people with lower limb amputation. Faster gait speed was associated with higher K-level and higher function, as well as being younger, male, and having a transtibial amputation with nonvascular aetiology. Understanding these personal and clinical factors associated with gait speed may be useful for refining rehabilitation programs that incorporate gait speed training during hospital rehabilitation. Further, a timed walking test may be a time-efficient indicator of prosthetic potential.Study 4 (Paper 4) explored factors associated with prosthetic prescription for walking. In a sample of 335 people with lower limb amputation, people were more likely to be prescribed a prosthesis if they were younger, male, had a unilateral transtibial amputation, had higher levels of cognition, were not undergoing dialysis, and prior to amputation they lived alone with no services and walked unaided indoors. Findings from this study inform practice by identifying factors that are associated with prosthetic walking prescription.Study 5 (Paper 5) used qualitative methodology to explore perceived barriers and enablers to walking with a prosthesis in the community. Barriers related to body function and structure included prosthetic function, residual limb integrity, phantom limb pain and other medical issues, with optimal prosthetic function and adequate fitness identified as enablers. Personal barriers included challenges adjusting to change, whereas personal enablers included being able to adjust to change, having a positive attitude, goal setting and having a purpose for community walking. Environmental barriers were physical (e.g. terrain, crowds and climate) and social (e.g. unwanted attention and finances). Environmental enablers included appropriate aids, transport, preparation, social support and finances. Improved understanding of these factors may inform service delivery to assist people with lower limb amputation to prepare for walking in the community.The results of the studies in this thesis provide insight into the characteristics and outcomes of a large group of people with predominantly dysvascular lower limb amputation who participated in subacute inpatient rehabilitation. This research may equip the multidisciplinary rehabilitation team to identify and manage risk factors that may contribute to adverse outcomes at hospital discharge. Identifying these factors may also limit readmissions to hospital and enable individuals with a lower limb amputation to transition successfully from hospital to the community. Findings from this research may assist clinicians in their decisions regarding prosthesis prescription. It is anticipated that new knowledge presented in this thesis will lead to more informed utilisation of hospital resources and to provide support for those seeking to ensure that individuals who would benefit from a prosthesis are provided with the opportunity to consider prosthetic rehabilitation.