Exploring Variations in Lumbar Canal Width: An MRI Study on Asymptomatic Patients by Age and Gender

Abstract

Background: Lumbar spinal stenosis is a common degenerative condition, especially in older adults, leading to significant morbidity. Age, gender, and lumbar level variations in spinal canal width are critical in assessing stenosis risk. Many patients exhibit radiographic narrowing without clinical symptoms. This study analyzed the risk of lumbar stenosis by age, gender, and lumbar levels (L1-S1) using the MRI of patients without clinical signs of narrowing. Materials and Methods: This retrospective study included 120 patients, aged 20 to 75, who underwent lumbar MRI for unrelated reasons. Spinal canal widths were measured at five lumbar levels (L1-2 to L5-S1), and stenosis risk was classified as low, borderline, or high based on narrowing thresholds. Data were grouped by age and gender to assess the stenosis risk distribution. Results: The analysis revealed a progressive increase in stenosis risk from the upper to lower lumbar levels. At L4-5 and L5-S1, females aged 61–75 exhibited the highest proportions in borderline- and high-risk categories. While most patients were classified as low risk, many older patients showed radiographic narrowing without clinical symptoms. Males generally had wider canals and lower risk. Conclusions: Age and gender significantly impact lumbar stenosis risk, particularly in older females. The findings highlight the importance of clinical correlation despite radiographic evidence of stenosis and suggest potential for AI-based detection systems in enhancing assessments of spinal canal narrowing.