Unilateral biportal endoscopic transforaminal lumbar interbody fusion reduces paravertebral muscle atrophy and enhances recovery compared with Wiltse-transforaminal lumbar interbody fusion in lumbar degenerative disease: a retrospective study in a Chinese cohort

Study Design: Retrospective study. Purpose: To compare postoperative paravertebral muscle atrophy, fat infiltration, and clinical efficacy between unilateral biportal endoscopic transforaminal lumbar interbody fusion (UBE-TLIF) and Wiltse approach transforaminal lumbar interbody fusion (W-TLIF). Overview of Literature: The long-term effects of UBE-TLIF and W-TLIF techniques on paravertebral muscle integrity and clinical outcomes have not been directly compared. Methods: Fifty patients who underwent UBE-TLIF and 50 patients who underwent W-TLIF, each with >2 years of follow-up, were retrospectively analyzed. Outcomes included operative parameters, time to postoperative mobilization, paravertebral muscle atrophy and fat infiltration rates, clinical scores (Visual Analog Scale [VAS], Oswestry Disability Index [ODI], Japanese Orthopaedic Association [JOA]), modified Macnab criteria, fusion rates, and complications. Results: Compared with W-TLIF, the UBE-TLIF group had significantly less intraoperative blood loss, shorter operative times, and lower postoperative drainage volumes (p <0.05). The UBE-TLIF group showed faster postoperative recovery and shorter hospital stays. At 6 months, 1 year, and 2 years, W-TLIF patients had higher multifidus and erector spinae atrophy, and greater paravertebral muscle fat infiltration (p <0.05). The UBE-TLIF group also had lower VAS and ODI scores at 1 year and 2 years (p <0.05) and fewer surgical complications (6% vs. 10%). Fusion rates (94% vs. 92%) and modified Macnab outcomes (88% vs. 86%) were comparable (p >0.05). Conclusions: UBE-TLIF is associated with reduced intraoperative trauma, quicker recovery, and fewer complications. In the long-term, it better preserves paravertebral muscle integrity and provides superior pain and functional outcomes.