Introduction: With vertebral compression fractures (VCF), the height loss has been associated with kyphotic deformity and intractable pain—two indications for potential surgical intervention. Consequently, assessment of factors associated with continual height loss can provide insights regarding management. Computed tomography Hounsfield units (CT HU), a measure of radio-density, has been implicated for the assessment of bone quality. No studies have assessed the relationship between CT HU and traumatic VCF. Consequently, the objective of this study was to evaluate this relationship, with the hypothesis that lower CT HU is associated with progressive worsening of traumatic VCF.

Methods: Patients who sustained a traumatic VCF from a motor vehicle accident from 2006 to 2015 were reviewed retrospectively. Inclusion criteria were single VCF from L1 to L4, appropriate imaging, and appropriate follow up. Clinical data was extracted [age, gender, and body mass index (BMI), length of follow up]. Initial CT imaging was evaluated for averaged HU at the levels above and below the index level of the VCF. Interval percentage change (IPC) in anterior compression was evaluated between x rays obtained during initial presentation and at follow-up.

Results: Age, BMI, and CT HU values significantly correlated to IPC (p < 0.01) while initial height loss and length of follow up did not. A multiple linear regression for IPC that combined age, BMI, and CT HU values elicited a regression model with R2 0.648, and adjusted R2 0.606; each variable in the model exhibited p < 0.05.

Conclusions: Based on this study, age, BMI, and CT HU values significantly correlated with worsening VCF and are independent predictors of worsening VCF. These factors can help determine appropriate clinical follow-up and need for surgical intervention.

Patient Care: Provide another predictor for progression of vertebral compression fractures that can help clinical management

Learning Objectives: 1) Evaluate the utility of CT HU values 2) Understand the predictors for worsening of vertebral compression fractures

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