Weight-Bearing Computed Tomography of the Foot and Ankle in the Pediatric Population

Abstract

Background: Newer cone-beam computed tomography (CT) technology has grown in popularity for evaluation of foot and ankle pathology in the weight-bearing (WB) position. Many studies have demonstrated its benefits within the adult population, but there is a paucity of its use within the pediatric literature. The purpose of this study was to describe the indications and clinical findings of WBCT within a pediatric population.

Methods: A retrospective cohort of 68 patients (86 extremities) who underwent WBCT for a variety of conditions were compared with 48 patients (59 extremities) who underwent traditional supine nonweight-bearing (NWB) CTs. Clinical indications, demographic data, radiation doses, and cost were obtained from the medical record. WBCTs were obtained in a private outpatient orthopaedic clinic, and the conventional NWBCTs were obtained within a hospital-based system.

Results: The most common indications for obtaining a WBCT and NWBCT in our study were fracture, tarsal coalition, and Lisfranc injury. The average WBCT radiation dose was 0.63 mGy for patients <100 lbs and 1.1 mGy for patients >100 lbs undergoing WBCT. For NWBCTs, the average radiation dose was 7.92 mGy for patients <100 lbs and 10.37 mGy for patients greater than 100 lbs. There was a significant reduction in radiation dose for all patients who underwent WBCT (P<0.0001 vs. 0.002). The average reimbursement for NWBCTs was $505 for unilateral studies and $1451 for bilateral studies. The average reimbursement for the WBCTs was $345 for unilateral studies and $635 for bilateral studies.

Conclusions: WBCT offers a new modality for studying complex foot and ankle pathoanatomy in the pediatric population at a reduced radiation exposure and reduced cost.

Level of evidence: Level III-a retrospective comparative study.