INTRODUCTION: The number of patients diagnosed with diabetes mellitus (DM) is increasing worldwide. Several reports demonstrated that DM is a risk factor for surgical site infection or other complications following lumbar surgery. Additionally, DM sometimes causes peripheral neuropathy or angiopathy; however, there are few reports regarding the outcome of lumbar surgery in patients with DM. The purpose of this study was to assess and compare the outcome of lumbar surgery in patients with and without DM.
METHODS: The study was a retrospective chart analysis conducted in our institution. The participants were consecutive patients aged 50 and older undergoing discectomy, posterior decompression or spinal instrumentation for lumbar disc herniation or spinal stenosis from 2006 to 2009. We assessed clinical and demographic data of patients, surgical procedures and intensity of low back pain, leg pain and leg numbness using a visual analogue scale pre‐and post‐operation. Functional outcome was also evaluated using the Japanese Orthopaedic Association (JOA) score for low back pain pre‐and post‐operation.
RESULTS: A total of 41 patients with DM (DM group) and 132 patients without DM (control group) were included in this study. There were no significant differences in pre‐ and post‐operative JOA score between the groups. However, the reduction in low back pain and leg numbness post‐operation were significantly lower in the DM group compared with the control group (p = 0.042 and 0.041, respectively). Reduction of low back pain in the DM group with instrumentation surgery was especially low compared with the control group with instrumentation surgery.
DISCUSSION: In conclusion, the functional outcome of lumbar surgery in patients with DM was comparable with that in those without DM; however, improvement of low back pain and leg numbness was worse in patients with DM.