Comparison of complications of biportal endoscopic discectomy: ipsilateral versus contralateral approach

Background: Biportal endoscopic discectomy using the contralateral approach is effective for highly down- or upward-migrated disc removal and upper lumbar disc herniation. Despite its benefits, there are potential complications that have yet to be fully explored, including possible transient neurological deficits, excessive nerve pull, and incomplete discectomy. Thus, in this study, we aimed to understand these complications by comparing the contralateral and ipsilateral approaches for biportal endoscopic discectomy. Methods: This study included 326 patients who underwent biportal endoscopic discectomy, with 168 and 158 patients undergoing endoscopic discectomy via the contralateral and ipsilateral approaches, respectively, between March 2020 and July 2023. Patient demographic characteristics, operation level, length of hospital stay, blood loss, and operation time were reviewed. Complications included early recurrence, neurological deficits, postoperative pain, and long-term recurrence. Only single-level patients were included. Patients with infections, stenosis, instability, tumors, revision surgery, multilevel pathology, or ambiguous symptoms were excluded. Results: Operation time, length of hospital stay, and blood loss were similar between groups. L3–4 and L4–5 were the most common contralateral and ipsilateral approach discectomies, respectively. The frequency of dural tear occurrence showed no difference between groups. Early recurrence occurred more in the ipsilateral than in the contralateral approach group. Neurological deficits occurred more in the contralateral than in the ipsilateral approach group. Postoperative pain and long-term recurrence rates were not significantly different between groups. However, the rate of revision surgery due to long-term recurrence was higher in the contralateral than in the ipsilateral approach group. Conclusions: No significant differences were observed in duration, postoperative pain, or long-term recurrence between the ipsilateral and contralateral approaches. However, early recurrence, neurological deficit, and revision surgery rates differed between the ipsilateral and contralateral approaches. The appropriate approach should be carefully determined according to the case before surgery. Contralateral discectomy may be an excellent surgical option.