Quality of Life Outcomes with Minimally Invasive Transforaminal Lumbar Interbody Fusion Based on Long-term Analysis of 304 Consecutive Patients

Presented at SMISS Annual Forum 2013
By Mick J. Perez-Cruet MD, MS
With Evan M. Begun BS, Daniel K. Fahim MD, G. Zachary White BS, Robert A. Collins DO, Namath S. Hussain MD, MBA,

Disclosures: Mick Perez-Cruet MD, MS None Evan Begun BS None, Daniel Fahim MD None, G. White BS None, Robert Collins DO None, Namath Hussain MD, MBA None,

Introduction: Long-term prospective outcomes in patients undergoing minimally invasive spinal fusion for debilitating back pain has not been well studied. The purpose was to demonstrate the short/long-term outcomes from a large cohort of patients undergoing minimally invasive transforaminal lumbar interbody fusion (MITLIF).

Methods: MITLIF was performed on 304 consecutive patients (184 females, 120 males) over a 7-year period from December 2003 to December 2010. Mean age was 62 years (range,19-93). Patients presented with lumbar spondylolisthesis with/without spinal stenosis (levels=236, 74%) and/or degenerative disc disease with/without spinal stenosis (levels=82, 26%). Outcome measures included the visual analog scale (VAS), Oswestry disability index (ODI), and the Short-Form 36 (SF-36). Presenting diagnosis was determined from clinical findings and radiographic (X-ray, MRI, CT-scan) evaluations pre-operatively. Outcomes were collected pre-operatively, and post-operatively at two weeks, and 3, 6, 12, 24 months, and annually 2-7 years (mean follow-up: 47 months). Complications and re-operations at the initial level of MITLIF and adjacent level (s) were followed. Fusion rates were assessed blinded and independently by radiograph.

Results: VAS scores decreased significantly from 7.0 pre-operatively to 3.5 (p-value <0.05) at mean 47-month follow-up. ODI scores declined from 43.1 pre-operatively to 28.2 (p-value <0.05) at mean 47-month follow-up. SF-36 mental component scores (MCS) increased from 43.8 pre-operatively to 49.7 (p-value <0.05) at 47-month follow-up. SF-36 physical component scores (PCS) increased from 30.6 pre-operatively to 39.6 (p-value <0.05) at 47-month follow-up.Reoperation rate was 3.9% (n = 12) with adjacent level pathology requiring reoperation 2% (n= 6). Complications were low and fusion rates were greater than 95%.

Conclusion: This large prospectively collected outcomes study shows long-term statistically significant improvement after MITLIF. MITLIF resulted in a high rate of spinal fusion and very low rate of interbody fusion failure and/or adjacent segment disease requiring re-operation while reducing post-operative complications.