Comparison of Two Minimally Invasive Techniques with Endoscopy and Microscopy for Extraforaminal Disc Herniations.

Abstract Objective Extraforaminal disc herniations(EFDHs) are extraordinary herniations because they are located outside the foraminal bony borders and compress the root exiting at the corresponding level, whereas in median or paramedian herniations, the root one level below is compressed. Percutaneous endoscopic discectomy(PED) and microscopic extraforaminal discectomy(MEFD) are two popular contemporary techniques that have been performed extensively for these herniations since the 1970s. Methods In this study, we retrospectively analyzed 118 patients who underwent either PED(66 patients) or MEFD (52 patients). All the patients were clinically evaluated for neurological examination findings, visual analog scale (VAS) scores for leg pain and Oswestry disability index (ODI) scores preoperatively and on the 7th postoperative day as well as 6 and 12 months after surgery. The complication rates and types of both techniques were discussed. Results The preoperative VAS and ODI scores were all comparable. Improvements in VAS scores 6 months postoperatively and improvements in ODI scores at all follow-up periods were statistically significant in favor of PED. However, interestingly, there was great discrepancy regarding the postsurgical complications in favor of MEFD. Conclusion PED is more prone to complications because this technique is strictly dependent on the tubular system and the ideal anatomy of Kambin’s triangle. Variations in or degeneration of Kambin’s triangle can lead to devastating complications in the PED technique, but normal anatomic conditions are feasible only in approximately 20% of patients. The most important feature of this study was that both techniques were performed by the same experienced team that developed its own concept.