Bone Physiology & Mechanics in Osteomyoplasty Amputation Rehabilitation

The purpose of the study is to compare the effect of different lower limb amputation surgical procedures on leg bone integrity and rehabilitation outcome.

Osteoporosis leading to increased risk of fracture, especially in the ipsilateral limb, is well documented in lower limb amputees. The purpose of this research is to examine the clinical utility of two amputation surgical procedures in: a) minimizing short and longer-term deleterious effects of amputation on bone integrity relative to the antecedents of osteoporotic change: reduced weight bearing capacity, inflammation, impaired muscle viability, and vascular compromise, and b) deriving benefit from prosthetic rehabilitation and exercise interventions. In a randomized controlled clinical trial, we will test the hypotheses: In lower limb traumatic and dysvascular amputation, when compared to the transtibial long posterior flap amputation technique and the transfemoral Gottschalk method, the osteomyoplastic reconstruction technique developed by Ertl: Hypothesis 1: results in fewer detrimental effects on bone metabolism, structure, and mass. Hypothesis 2: leads to optimal rehabilitation and functional outcomes. Specifically, we will examine, in traumatic and dysvascular lower limb amputees randomly assigned to undergo either the long posterior flap amputation method or amputation with osteomyoplastic reconstruction in transtibial amputation and either the Gottschalk amputation method or amputation with osteomyoplastic reconstruction in transfemoral amputation, differences in the following parameters at baseline, 6 weeks (post-operative recuperation), and 6 months (termination of supervised rehabilitation and exercise intervention). We will assess bone integrity in patients undergoing standard amputation versus osteomyoplastic reconstruction by measuring bone metabolism and bone mineral density and mineral content. Second, we will measure inflammatory response in patients undergoing standard amputation versus osteomyoplastic reconstruction by assessing weight bearing and impact, muscle integrity, and limb vascularity. Last, we will compare rehabilitation and functional outcome in patients undergoing standard amputation versus osteomyoplastic reconstruction by assessing prosthetic mobility, functional capacity, activity levels, and quality of life.

Inclusion Criteria: Adult lower limb PVD-related or traumatic amputees who are appropriate candidates for amputation rehabilitation exercise. Exclusion Criteria: Cognitive dysfunction (MiniMental scores <23), advanced neuropathies, or neurological impairment (CVA, Parkinson's) with residual loss of function enough to preclude exercise; Unresolved MI (high isoenzymes), angina, arrhythmia, 3rd degree AV block, fixed-rate pacer; Recent embolus/thrombophlebitis, myocarditis, pericarditis, or cardiomyopathy; Resting SBP >200mmHg or DBP >100mmHg; Uncontrolled metabolic disease, liver or kidney failure, alcohol/drug addiction; acute infection; Exercise-exacerbated neuromuscular/musculoskeletal disorders; irreducible hip/leg contractures.