Complication assessment in full-endoscopic uniportal lumbar spine surgery: A prospective analysis from 304 patients.

Introduction: Full-endoscopic uniportal spine surgery is increasingly used as a minimally invasive alternative to conventional open or microsurgical techniques. To date, prospective data on complication profiles and procedure-related risk factors remain limited, at times with inconsistent results across the literature and potential underreporting of complications. Research question: To prospectively assess complication and reoperation rates following full-endoscopic uniportal spine surgery in a consecutive patient cohort and to identify relevant risk factors that may be associated with adverse events. Materials & methods: A prospective cohort of 304 consecutive patients undergoing full-endoscopic uniportal procedures was analyzed. All procedures were primary surgeries and included bilateral over-the top decompressions (n = 111, 37%), n = 196 discectomies/sequestrectomies (65%), ipsilateral recess decompressions (n = 30, 10%) or a combination of the aforementioned. Given that the primary aim of this study was perioperative risk and complication assessment, an observation period of 6 months (range: 6-30 months) was defined for inclusion in this study.Univariable logistic regression analysis with odds ratios and corresponding 95% confidence intervals were used to analyze potential risk factors. Results: The cohort comprised 190 men (62%) and 114 women (38%) with a mean age of 60 ± 15.6 years (range 16-88). 55% of the patients (n = 167/304) were older than 60 years, including 24% aged 70-80, and 8% aged >80 years, respectively. 61% of patients were either overweight (n = 109, 36%; BMI 25.0-29.9) or obese with a BMI >30.0 (n = 72 patients, 24%).Procedures were performed single-level in 76% of all cases (n = 232/304), 24% were performed as multi-level interventions (n = 72/304).Complications occurred in n = 20 patients, corresponding to an overall complication rate of 6.6% (20/304). The reoperation rate was 4.9% (15/304). Incidental intraoperative laceration of the dural sack was encountered in n = 2 patients (0.6%). A recurrent disc herniation occurred in n = 6 patients (3.1% of n = 196 discectomy patients).Postoperative epidural hematoma occurred in 7 patients (2.3%) and was significantly associated with advanced age (mean 78.4 ± 5.9 years), multilevel surgery (4/7 hematomas), and longer operative time (p < 0.05).Age was a strong predictor, with an odds ratio of 4.85 per 10-year increase (95% CI 1.54-15.29; p = 0.007), corresponding to an estimated risk increase from 1.7% at 70 years to 8% at 80 years. There was no epidural hematoma in patients below the age of 70.No deep surgical site infections (SSI) or deep wound-healing complications were encountered. Discussion and conclusion: Data from this prospective series indicate an adequate patient safety for uniportal interlaminar endoscopic surgeries, with an overall acceptable rate of complications and reoperations.The occurrence of complications is largely influenced by a combination of higher procedural complexity and patient-related vulnerability, even in a seemingly healthy but still elderly patient population.The absence of deep surgical site infections underscores a favorable safety profile, even though a substantial proportion of patients presented with well-known relevant risk factors.Based on studies of this kind, ongoing technical advances i.e. in the field of hemostasis may serve to further reduce complication rates and help improve patient safety in the future.