Isolated transverse process fractures: insignificant injury or marker of complex injury pattern?

This study investigates the incidence of isolated transverse process fractures (ITPFx) amongst vertebral fractures in trauma patients, and specific-associated injury patterns present in patients with ITPFx.

A retrospective, 4-year review of our Level 1 Trauma Center registry was performed. Patients with blunt spinal column fractures were identified. Data collected included patient demographics, Injury Severity Score (ISS), type of imaging obtained, and concomitant injuries, including rib and pelvic fractures, liver, spleen, and kidney injury (SOI).

Of the 10,186 patients admitted during the study period, 881 (8.6%) suffered blunt thoraco-abdominal trauma resulting in vertebral fractures; 214/881 (24%) had ITPFx. All patients (10,186) underwent dedicated spinal multi-detector CT (MDCT) imaging; 26/214 (12.1%) patients had MRI. In all 26 patients, the MRI confirmed the CT findings. 202/214 (94.4%) had associated injuries: rib and pelvic fractures, 45.5 and 20.2%, respectively, and splenic, liver and kidney injury with an incidence of 13.8, 10.9, and 9.4%, respectively. A higher incidence of rib fractures was associated with ITPFx at the T1-4 levels, whereas ITPFx at the level of L5 were associated with pelvic fractures and SOI. Multiple logistic regression analysis identified T1-4 and L5 fractures as predictors of rib fractures and pelvic fractures independent of ISS, with OR: 2.55 (95% CI: 1.12-5.82) and 6.81 (95% CI: 3.14-14.78), respectively.

Based on the results of this study, we conclude that: (1) the use of MDCT imaging has increased the rate of identification of ITPFx; (2) dedicated spinal MDCT reconstruction and MRI may not be necessary to diagnose isolated thoracic and lumbar ITPFx; and (3) ITPFx of the thoracic spine and lower lumbar spine are markers of associated rib fractures and pelvic ring fractures, respectively, as well as of solid organ injuries.