Recurrence Is Associated With Body Mass Index in Patients Undergoing a Single-Level Lumbar Disc Herniation Surgery.

Background: The aim of the study was to assess the body mass index (BMI) and other risk factors associated with lumbar disc herniation (LDH) and clinical outcomes, in patients who undergo surgery for single-level LDH.

Methods: This was a retrospective cohort study, affecting patients that underwent surgery for single-level LDH attending our hospital between July 2009 and January 2016. The mean follow-up period was 3.5 years (1 - 8 years). To maintain adequately sized groups for analysis, level L2-L3 and L3-L4 herniations were grouped as upper disc levels (group A) and level L4-L5 (group B) and L5-S1 (group C) herniations were analyzed individually. Disk herniation was graded on T2-weighted sagittal magnetic resonance images by using a five-point scale. Pain assessment was made using the visual analog scale (VAS).

Results: Two hundred fifty-six (256) patients met study inclusion criteria. There were 138 males (53.9%) with a mean age of 55.3 ± 12.9 years (range, 30 - 77). The association between A, B and C groups was analyzed, based on criteria such as age, sex, BMI, surgical techniques, diabetes, size of herniated disc, preoperative VAS, length of hospital stay, drop foot on admission, smoking, family history and history of injury to the lumbar spine, location of herniated disc (far lateral) and use of steroids. We found a statistically significant factor between groups in BMI (P = 0.006), family history (P = 0.001), location (far lateral) (P = 0.003) and history of injury to the lumbar spine (P = 0.003).

Conclusions: There may be an association between severity of disc degeneration and BMI (overweight and obese adults). Furthermore, spine and neurosurgeons should be aware that BMI might be related to patients' outcome.