Recurrence of lumbar disk herniation after microdiscectomy: a two-center retrospective analysis of 1214 cases and identification of risk factors.

Background/aim: To present the incidence of recurrent lumbar disc herniation (RLDH) and to identify radiological and patient-related risk factors that lead to recurrence after lumbar disc herniation (LDH) treatment with microdiscectomy. Materials and methods: Between January 2013 and December 2021, 1214 patients who had undergone microdiscectomy for LDH were included in this retrospective study. Patients were divided into two groups, the recurrent group and the non-recurrent group, and their demographic, clinical and radiologic characteristics were recorded. The association between the variables and RLDH was assessed by univariate and multivariable logistic regression analyses. Results: Mean ages were similar in the recurrent (51.48 ± 13.63) and non-recurrent(50.38 ± 14.53) groups (p=0.232). Males represented 59.6% of the recurrent group and 49.8% of the non-recurrent group (p=0.002). Multivariable logistic regression revealed that being a male (p=0.009), diabetes mellitus (p=0.038), smoking (p<0.001), grade 4&5 disc degeneration (p<0.001), and having protruded (p=0.002), extruded LDH (p<0.001), paracentral (p=0.008) and foraminal LDH (p=0.008) were independently associated with recurrence. Conclusion: To reduce RLDH frequency and need for revision surgery, modifiable risk factors should be minimized before and after the initial surgery. Also, in patients with unmodifiable risk factors, patients should be clearly informed about the risk for recurrence and possible alternative treatment methods should be considered.