Citation

Flint JH, Wade AM, Stocker CP, Pasquina CP, Howard RS, Potter MP. J. Orthop. Trauma 2014; 28(4): 238-244.

Affiliation

1Walter Reed National Military Medical Center, Bethesda, MD 2Uniformed Services University of Health Sciences, Bethesda, MD.

Copyright

(Copyright © 2014, Lippincott Williams and Wilkins)

DOI

10.1097/BOT.0b013e3182a66a8a

PMID

23912861

Abstract

OBJECTIVES:: Determine the incidence, severity, and associated risk factors for the development of low bone mineral density (BMD) following combat-related lower extremity amputation. DESIGN:: Retrospective, case-control comparison SETTING:: Tertiary care military treatment facility PATIENTS/PARTICIPANTS:: One hundred fifty-six lower extremity amputees, representing 182 amputations (121 unilateral, 35 bilateral). INTERVENTION:: All patients underwent dual energy x-ray absorptiometry (DEXA) scanning during the treatment period. MAIN OUTCOME MEASUREMENTS:: Z-score was the main outcome measure. We identified all patients with low BMD (Z<-1.0) and conducted multivariate analysis to identify significant risk factors for low BMD development. RESULTS:: The observed rate of low BMD was 42%. The average Z-score was -0.6±1.1 among unilateral amputations, and -1.2 ±1.0 among bilateral amputations (p=0.005). Risk factors for the development of low BMD were prolonged time to first ambulation (OR=1.39; 95% CI: 1.003-1.93; p=0.048), prolonged time to DEXA (OR=1.10; 95% CI: 1.02-1.18; p=0.009), and more proximal amputation level (OR=7.27; 95% CI: 3.21-16.49; p<0.001). Among unilateral amputees, we detected a significant difference in the BMD of the intact and amputated limbs (-1.0; 95% CI: -1.1 to -0.8; p<0.001). CONCLUSIONS:: Proximal amputation level and delayed ambulation demonstrated a significant relationship with low BMD following traumatic and trauma-related amputation. We conclude that transfemoral amputees are at greater risk of BMD loss, and that disuse atrophy is a primary factor in the development of low BMD. Prevention should focus on early and aggressive weight-bearing rehabilitation, as well as assessing levels and appropriately supplementing calcium and vitamin D.

Language: en