Influence of traumatic lower-limb amputation on physical activity, body composition and cardiometabolic risks: A descriptive preliminary study

Background: Following traumatic lower-limb amputation (LLA), humans are predisposed to numerous unfavorable changes in health, including the development of secondary chronic health conditions such as metabolic disorders and cardiovascular disease. Objective: To determine within and between group differences in cardiometabolic component risks, body composition, and physical activity (PA) in individuals with traumatic unilateral and bilateral LLA, compared to noninjured controls. Design: Prospective observational cohort study. Setting: A military complex trauma rehabilitation center. Participants: Sixteen males with traumatic LLA (8 unilateral, mean age 30 ± 5 years and 8 bilateral, mean age 29 ± 3 years). Thirteen active age-matched males with no LLA (28 ± 5 years) acted as controls and performed habitual activities of daily living. Intervention: Participants with LLA attended two 4-week periods of inpatient rehabilitation, separated by two 6-week periods of home-based recovery. Main Outcome Measures: Venous blood samples were taken prior to and following a 75 g oral glucose load, for determination of biomarkers, including insulin and glucose, at baseline and 20 weeks. Body composition (dual X-ray absorptiometry) was measured at baseline, 10 weeks, and 20 weeks. Daily PA was recorded using a triaxial accelerometer for 7 days during inpatient rehabilitation and while at home. Energy expenditure was estimated using population-specific equations. Results: Individuals with bilateral LLA demonstrated more unfavorable mean body composition values, lower PA, and increased cardiometabolic health risk compared to controls. Cardiometabolic syndrome was identified in 63% of individuals with bilateral LLA. No statistically significant differences in cardiometabolic component risk factors, body composition, and estimated daily PA were reported between unilateral LLA and control groups (p >.05). While at home, mean PA counts.day ⁻¹ reduced by 17% (p =.018) and 42% (p =.001) in the unilateral and bilateral LLA groups, respectively. Conclusions: Despite extensive inpatient rehabilitation, cardiometabolic component risks are elevated in individuals with bilateral LLA but are comparable between unilateral LLA and active noninjured control groups. Innovative strategies that improve/support the long-term PA and cardiometabolic health of severely injured individuals with bilateral LLA are warranted.