The relationship between the cross-sectional area of the cauda equina and the preoperative symptoms in central lumbar spinal stenosis

Study Design. A cross-sectional registry and imaging cohort study. Objectives. To study the association between typical symptoms and signs of central spinal stenosis and the minimum cross-sectional area (mCSA) of the cauda equina in patients subsequently undergoing surgery. Summary of Background Data. Relations between mCSA and the symptoms of spinal stenosis have not been studied before. Subjects and Methods. The preoperative walking ability, pain in the leg(s) and back, duration of symptoms and quality of life in 82 men and women subsequently operated for spinal stenosis were related to the digitally determined CSA of the single most constricted level, mCSA of their lumbar spines. Results. A smaller mCSA was directly related to a shorter walking distance before claudication. A small mCSA meant more leg and back pain and a lower health-related quality of life. For those with a walking ability < 100 m, the average mCSA was around 53 mm(2); whereas it was just < 69 mm(2) for those able to walk > 500 m. The average mCSA did not differ depending on gender, age, or vertebral level. Conclusions. The mCSA was a strong predictor of the preoperative walking ability, leg and back pain, and was directly related to the quality of life of patients with central spinal stenosis.