Prevalence and Predictive Factors of Asymptomatic Spondylotic Cervical Spinal Stenosis in Patients with Symptomatic Lumbar Spinal Stenosis.

OBJECTIVE

We performed a retrospective cohort study to investigate the prevalence of and risk factors for asymptomatic spondylotic cervical spinal stenosis (ASCSS) in the setting of lumbar spinal stenosis (LSS).

METHODS

A total of 114 patients with a diagnosis of LSS without cervical myelopathy and radiculopathy were grouped into ASCSS and non-ASCSS groups. The medical data and radiological parameters, including age, sex, body mass index, Charlson comorbidity index, symptom duration, redundant nerve roots, dural sac cross-sectional area (DCSA), facet joint angle, lumbar lordosis angle (LLA), pelvic incidence (PI), Torg-Pavlov ratio, and lumbosacral transitional vertebrae, were analyzed. The lumbar stenosis index and cervical stenosis index of the 114 patients were also analyzed.

RESULTS

ASCSS occurred in 70 of the 114 patients with LSS (61.4%). The two groups showed significant differences in symptom duration, redundant nerve roots, LLA, DCSA, and PI. On multivariate logistic regression analysis, an LLA >35.85° (P < 0.001) and a DCSA <84.50 mm2 (P = 0.003) were independently associated with ASCSS. The multi-index receiver operating characteristic curve showed that the area under the curve for predicted probability was 0.805 (P < 0.001). Linear regression analysis revealed that cervical stenosis index significantly and positively correlated with the lumbar stenosis index (r = 0.430; P < 0.001).

CONCLUSIONS

Our findings suggest that an LLA >35.85° and a DCSA <84.50 mm2 are risk factors for the development of ASCSS. For LSS patients with an enlarged LLA and reduced DSCA, a whole spinal magnetic resonance imaging examination should be performed.