Biportal Endoscopic Lumbar Interbody Fusion With 3D Printed Double Cage: Technical Note and Preliminary Results.

STUDY

DESIGN

Case series.

OBJECTIVE

A small case series of biportal endoscopic transforaminal interbody fusion (BE-TLIF) has been reported. However, complications such as nonunion or subsidence can occur. The aim was to introduce the surgical technique of BELIF using two 3D printed cages.

METHOD: Between January 2023 and March 2024, 30 patients who underwent BE-TLIF for degenerative or isthmic spondylolisthesis that were followed for at least a year were enrolled. A 2-cage insertion technique was performed using 3D printed titanium cages. Visual analog scale (VAS) of back and leg and Oswestry Disability Index (ODI) were collected perioperatively, and modified Macnab criteria were collected at the final follow-up. Fusion was assessed using computerized tomography (CT). Spinopelvic parameters were measured preoperatively and postoperatively.

RESULT: ODI scores improved from 63.24±6.72 preoperatively to 18.79±6.93 (P<0.001). VAS scores of the leg decreased from 7.23±0.94 to 1.26±0.51 (P<0.001). Per the modified Macnab criteria, 90% of the patients improved to good/excellent. The fusion rate at 1-year follow-up was 94.4% while pelvic tilt improved from preoperative 19.68±8.57 to 17.90±9.17 postoperatively (P=0.043). Two surgical complications occurred.

CONCLUSION

BELIF using a 3D printed double cage can be safely performed with decreased risk of subsidence and high rates of fusion.