Clinical and Radiological Outcomes of Minimally Invasive Versus Open Transforaminal Lumbar Interbody Fusion

Abstract

Prospective study. Comparison of clinical and radiologic outcomes of minimally invasive (MIS) versus Open transforaminal lumbar interbody fusion (TLIF). Open TLIF has been performed for many years with good results. MIS TLIF techniques have recently been introduced with the aim of smaller wounds and faster recovery. From 2004-2006, 29 MIS TLIF were matched paired with 29 Open TLIF. Patient demographics and operative data were collected. Clinical assessment in terms of North American Spine Society, Oswestry Disability Index, Short Form-36, and Visual Analogue scores were performed before surgery, 6 months and 2 years after surgery. Fusion rates based on Bridwell grading were assessed at 2 years. The mean age for MIS and Open procedures were 54.1 and 52.5 years, respectively. There were 24 females and 5 males in both groups. Fluoroscopic time (MIS: 105.5 seconds, Open: 35.2 seconds, P < 0.05) and operative time (MIS: 216.4 minutes, Open: 170.5 minutes, P < 0.05) were longer in MIS cases. There was less blood loss in MIS (150 mL) versus Open (681 mL) procedures (P < 0.05). The total morphine used for MIS cases (17.4 mg) was less compared to Open (35.7 mg, P < 0.05). MIS (4 days) patients have shorter hospitalization compared to Open (6.7 days, P < 0.05). Both MIS and Open groups showed significant improvement in Oswestry Disability Index (P < 0.05), back pain and lower limb symptoms (North American Spine Society and Visual Analogue scores, P < 0.05), and Quality of Life scores (Short Form-36, P < 0.05) at 6 months and 2 years, but there was no significant difference between the 2 groups. Eighty percent of MIS and 86.7% of Open TLIF levels achieved grade 1 fusion (P > 0.05). MIS TLIF has similar good long-term clinical outcomes and high fusion rates of Open TLIF with the additional benefits of less initial postoperative pain, early rehabilitation, shorter hospitalization, and fewer complications.