Modified minimally invasive transforaminal lumbar interbody fusion using a trans-multifidus approach: a safe and effective alternative to open-TLIF

BACKGROUND: Application of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) is limited by long fluoroscopy time and a steep learning curve. Herein, MI-TLIF was modified using a trans-multifidus approach, assisted by microscope, termed MMI-TLIF, and the clinical outcomes of MMI-TLIF and open-TLIF were compared. METHODS: Forty-nine patients treated with MMI-TLIF were matched with 49 subjects who underwent open-TLIF. Patients were assessed using the North American Spine Society Score (NASS), Oswestry Disability Index (ODI), Short Form-36 (SF-36), and Visual Analogue Score (VAS) before surgery and during follow-up (6 months and 2 years). The four-type Bridwell anterior fusion grading system was used to evaluate fusion rates at 2 years. RESULTS: The median fluoroscopic time did not differ significantly between the MMI-TLIF and open-TLIF groups. MMI-TLIF surgery took significantly longer than open-TLIF (91.3 vs. 82.5 min; P < 0.05). Meanwhile, MMI-TLIF patients lost significantly less blood than open-TLIF patients (75.3 vs. 215.2 ml; P < 0.05), and MMI-TLIF patients were hospitalized for less long than open-TLIF patients (3.7 vs. 6.9 days; P < 0.05) and reported less pain, faster ambulation, and lower morphine intake than open-TLIF patients (all P < 0.05). The NASS, ODI, VAS, and SF-36 scores were significantly improved 6 months and 2 years postsurgery in both groups, compared with preoperative values, and similar values were obtained for both groups. Finally, fusion rates were similar in MMI-TLIF and open-TLIF patients. CONCLUSIONS: Overall, these findings strongly suggest the superiority of MMI-TLIF to open-TLIF. Therefore, MMI-TLIF could be a safe and effective alternative to MI-TLIF and open-TLIF.