Analysis of the clinical characteristics and predisposing factors for neurological deficit with Hangman fractures.

BACKGROUND

Hangman fracture is the second most common injury of the upper cervical spine, and neurological deficit with Hangman fracture is not rare. To our knowledge, few reports have statistically analyzed the predisposing factors for this injury. The objective of this study was to describe the clinical characteristics of neurological deficit associated with Hangman fracture and evaluate its risk factors.

METHODS

In this retrospective study, 97 patients with Hangman fractures were included. Data on the age, sex, injury etiology, neurological deficits, and associated injuries were obtained and evaluated. The pretreatment parameters, anterior translation and angulation of C2/3, presence of the posterior vertebral wall (PVW) fractures of C2, and presence of spinal cord signal changes were measured. Twenty-three patients with neurological deficits after Hangman fractures comprised group A, and 74 patients without neurological deficit comprised group B. Student's t-test or a nonparametric test and the chi-square test were used to evaluate the differences between groups. Binary logistic regression analysis was used to identify the risk factors for neurological deficit.

RESULTS

Among the 23 patients in group A, 2 were American Spinal Injury Association (ASIA) scale B, 6 were C, and 15 were D, and spinal cord magnetic resonance imaging signal change was observed at the level of C2-C3 disc, C2, or both. Patients with the combination of PVW fractures and ≥ 50% significant translation or angulation of C2/3 were significantly more likely to have a neurological deficit. Both factors remained significant in binary logistic regression analysis.

CONCLUSIONS

Neurological deficit after Hangman fractures always presents clinically as a partial neurological impairment. The combination of PVW fractures with ≥ 1.8 mm of translation or ≥ 5.5° of angulation of C2/3 was the predisposing factor for neurological deficit with Hangman fractures.