This purpose of this study was to objectively evaluate and assess the efficacy and efficiency of discectomy and endplate preparation during transforaminal lumbar interbody fusion (TLIF) using traditional manual instrumentation versus a novel suction discectomy curette. Transforaminal lumbar interbody fusion is the most widely used approach for lumbar arthrodesis, and its success depends on the ability to achieve fusion. Complete preparation of intervertebral disc space (removal of the nucleus, endplate cartilage, and margin of inner annulus) is the surgical goal. Performing an adequate discectomy requires numerous instrument passes, increasing surgical time and the risk of complications.
Four experienced spinal surgeons performed transforaminal discectomies from T-12 to S-1 on 5 whole-body cadavers. Each level (n = 26) was randomly assigned to either a control group using traditional instruments (12 levels) or to a suction curette group (14 levels). The time required to perform the discectomy and the number of passes through the annulus were recorded. Motion segments were dissected and analyzed by digital photogrammetric analysis. The intervertebral disc and the discectomy cross-sectional areas were measured on both superior and inferior images of each dissected surgical level. Areas were divided into 4 quadrants based on a midsagittal and midcoronal axis and analyzed for regional efficiency. In addition, a cross-sectional area of bony endplate (the area still covered with cartilage) and an area of endplate perforation were evaluated.
There was no significant difference in surgical time between the techniques (7:51 ± 2:43 minutes in the manual discectomy [MD] group and 7:06 ± 3:33 minutes in the suction curette discectomy [SD] group). There were significantly fewer (p < 0.01) instrument passes in the SD group (13 passes) compared with the MD group (43 passes). For both techniques, the amount of disc removed depended upon the anatomical region, with the posterior-contralateral side having the least amount of disc material removed. There was significantly less (p < 0.01) disc material removed in the MD group (38%) compared with the SD group (48%). The amount of disc material removed was significantly more (p < 0.05) in each quadrant when comparing the SD and MD groups, with the anterior regions showing the largest difference. For both techniques, the preparation of the endplate within the discectomy area resulted in a mostly cartilaginous interface (50% MD, 48% SD); a smaller amount of bony interface area (31% MD, 38% SD); and a smaller amount of perforation to the interface area (19% MD, 13% SD). There were no significant differences between the groups in terms of endplate preparation.
The improved discectomy observed with the suction curette device could potentially improve the clinical fusion rate.