Body Mass Index as A risk Factor for Recurrence and Frequency of Re-surgery After Lumber Spine Surgery

Background: Obesity is a well-established risk factor for numerous health complications, yet its impact on postoperative recurrence and the need for re-surgery after lumbar spine surgery remains unclear. Lumbar spine surgery is a common treatment for degenerative spinal disorders; however, recurrence of symptoms and subsequent re-surgery continue to pose significant postoperative challenges. Body mass index (BMI) has been suggested as a potential risk factor affecting surgical outcomes due to its biomechanical and metabolic effects. This study aimed to evaluate the association between BMI and the risk of recurrence and re-surgery following lumbar spine surgery. Objective: To evaluate the association between BMI and the risk of recurrence and re-surgery after lumbar spine surgery. Methods: This is a retrospective cohort study that included adult patients who underwent a single stable lumbar spine discectomy for degenerative disc disease at Al-Ahrar Teaching Hospital and Zagazig University Hospitals, Zagazig, Egypt, between January 2015 and October 2025. Patients with multilevel disc pathology, concomitant cervical or thoracic spine disorders, unstable vertebrae, or a history of previous lumbar surgery were excluded. BMI was recorded at the time of the first surgery and at the follow-up. Results: The study included 286 patients (171 males and 115 females); we selected 286 cases from the hospital medical records, among more than 5,000 cases operated on during 10 years, with a mean age of 41.9 ± 11.2 years. Recurrence of lumbar surgery occurred in 28 patients (9.8%). Higher BMI was significantly associated with recurrence: 18 (64.3%) of overweight/ obese patients and required re-surgery, compared with 10 (35.7%) of patients with a healthy weight. The mean BMI at the time of the initial surgery was significantly higher in the recurrence group (25.8 ± 2.8 kg/m²) than in the non-recurrence group (22.9 ± 2.0 kg/m²; p < 0.001). Similarly, BMI at follow-up remained greater among patients with recurrence (25.0 ± 2.6 vs. 21.9 ± 2.1 kg/m²; p < 0.001). Obesity-related comorbidities were present in (66.7%) of patients, with type 2 diabetes (24.1%) and cardiovascular disease (18.3%) being the most common. Conclusion: Higher BMI is significantly associated with recurrence and need for re-surgery following lumbar spine surgery, identifying elevated BMI as an independent risk factor. BMI should be considered during preoperative risk assessment and postoperative counseling. Implementing weight optimization strategies before and after surgery may improve long-term outcomes and reduce recurrence rates.