Raman spectroscopic analysis of combat-related heterotopic ossification development

Authors

Nicole Crane, Naval Medical Research Center, Walter Reed National Military Medical CenterFollow
Elizabeth Polfer, Naval Medical Research Center, Walter Reed National Military Medical Center, Uniformed Services University of Health ScienceFollow
Eric Elster, Naval Medical Research Center, Walter Reed National Military Medical Center, Uniformed Services University of Health ScienceFollow
Benjamin Potter, Naval Medical Research Center, Walter Reed National Military Medical Center, Uniformed Services University of Health ScienceFollow
Johnathan Forsberg, Naval Medical Research Center, Walter Reed National Military Medical Center, Uniformed Services University of Health ScienceFollow

Date of this Version

2013

Citation

Bone 57 (2013) 335–342

Comments

This article is a U.S. government work, and is not subject to copyright in the United States.

Abstract

Over 60% of our severely combat-injured patient population develops radiographically apparent heterotopic ossification. Nearly a third of these require surgical excision of symptomatic lesions, a procedure that is fraughtwith complications, and delays or regresses functional rehabilitation in many cases. Unfortunately, for the combat injured, medical contraindications and logistical limitations limitwidespread use of conventionalmeans of primary prophylaxis. Better means of risk stratification are needed to both mitigate the risk of current means of primary prophylaxis as well as to evaluate novel preventive strategies currently in development. We asked whether Raman spectral changes, measured ex vivo, correlated with histologic evidence of the earliest signs of HO formation using tissue biopsies fromthewounds of combat casualties. In doing so, we compared normal muscle tissue to injured muscle tissue, unmineralized HO tissue, and mineralized HO tissue. The Raman spectra of these tissues demonstrate clear differences in the amide I and amide III spectral regions of HO tissue compared to normal tissue, denoted by changes in the 1640/1445 cm⁻¹(p < 0.01), and 1340/1270 cm⁻¹ (p < 0.01) band area ratios (BARs). Additionally, analysis of the bone mineral in HO by Raman spectroscopy appears capable of determining bone maturity by measuring both the 945/960 cm⁻¹ and the 1070/1445 cm⁻¹ BARs. Raman may therefore prove a useful, non-invasive, and early diagnostic modality to detect HO formation prior to it becoming evident clinically or radiographically. This technique could ostensibly be utilized as a non-invasive means to risk stratify individual wounds at a time thought to be amenable to various means of primary prophylaxis