Methods: LCS patients were divided into three groups as per DM status: group A without DM (n=150); group B patients with well-controlled DM; and group C patients with uncontrolled DM. Groups B and C were subdivided into group B1: patients with DM with a duration of ≤10 years (n=76), group B2: DM with duration of >10 years (n=68), group-C1 DM duration ≤10 years (n=56), and group C2 DM duration >10 years (n=48). The severity of LCS was evaluated using the Swiss Spinal Stenosis Scale (SSSS) and Modified Oswestry Disability score (MODS). Operated patients ligamentum flavum sent for histological staining and quantitative immunofluorescence analysis. Results: The demographic data of groups did not show any difference except in age. There was no difference between the mean SSSS and MODS of groups A and B1. Groups B2, C1, and C2 had higher average SSSS and MODS than group A (p<0.05). Groups B2 and C2 had higher SSSS and MODS than groups B1 and C1. Groups C1 and C2 had higher scores than groups B1 and B2 (p<0.05). The severity of LCS was significantly related to the duration of DM in groups B and C (p<0.05). Uncontrolled and longer duration of DM had significant elastin fibers loss and also higher rate of disk apoptosis, high matrix aggrecan fragmentation, and high disk glycosaminoglycan content. Conclusions Longer duration and uncontrolled diabetes were risk factors for LCS and directly correlate with the severity of LCS.