Introduction: Studies show cervical facet fracture instability is related to certain Computed tomography (CT) and Magnetic Resonance Imaging (MRI) findings. This retrospective descriptive study of patients with unilateral cervical facet fractures (UCFF) further examines CT and MRI findings associated with surgical and non-surgical management of such injury.

Methods: Demographic, clinical, and CT/MRI imaging data of patients with UCFF managed at University of Louisville Hospital, a level-1-trauma center, from 2011-2014 were collected and analyzed.

Results: UCFF from 212 patients were analyzed. 72% were male, 85% were white, average age was 42 years. Primary mechanism of injury was motor vehicle accident (76%). A majority of patients were GCS>13 (92%). 62 patients (33%) underwent instrumented fusion. Vertebral artery injury was present in 20 patients (11%). The most common injury level was C6-C7 (41%) and fracture height was greatest at C2-C3. Surgery was more frequently performed in patients with ligamentous injury: ligamentum flavum, posterior longitudinal ligament, and anterior longitudinal ligament (35.5%, 51.6%, 48.4%, respectively, p<0.05). Disc injury (29%) and herniated discs (20%) also associated more with surgical vs conservative management (75% vs 67%, respectively, p<0.05). Most common level to have surgery was C4-C5 (41%). SLIC<4 (62%) less commonly received surgical intervention (20%; p<0.05). SLIC=5 (27%) associated with a higher percentage of surgical intervention (91%, p< 0.05).

Conclusions: This study, one of the largest reported on UCFF studies, reports the level most commonly injured (C6-C7), and levels most associated with fracture height >1cm (C2-C3) and surgery (C4-C5), and quantifies significant rate of vertebral artery injury associated with these fractures. In agreement with previous literature, SLIC=5 predicted greater use of surgery with the majority managed surgically. The rate of floating fractures involving pedicle, facet, and lamina was quantified where the majority was managed conservatively. Future studies will be performed to compare outcomes between operated and non-operated floating fractures.

Patient Care: This study has potential to improve future patient care by providing reinforcing data of previous studies on certain characteristics and imaging findings associated with unilateral facet fractures to prompt further investigation and possible development of an algorithmic approach to unilateral cervical facet fractures.

Learning Objectives: By the conclusion of this session, participants should be able to discuss injury characteristics associated with unilateral cervical facet fractures and discuss CT and MRI findings or injury characteristics associated with surgically managed patients

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