Table 1. Demographic data.

	Trauma group (n = 34)	Nontrauma group (n = 70)	p Value
Sex (female: male)	7: 27	17: 53	0.678
Age at surgery (y)	56.24 ± 8.79	53.90 ± 9.30	0.225
Initial symptom involvement			0.218
Without lower extremities	13	36
With lower extremities	21	34
Symptom duration (mo)	17.68 ± 22.96	31.00 ± 39.57	0.033
Surgical approach			0.605
Anterior	14	33
Posterior	17	34
Combined anterior and posterior	3	3
Follow-up period (mo)	56.47 ± 51.25	47.73 ± 31.89	0.289