Introduction: Adoption of minimally invasive spinal fusion techniques have improved patient care but can be technically difficult. The purpose of this study was to investigate the safety and efficacy of the BoneBac Integrated Arthrodesis System for preforming minimally invasive transforaminal lumbar interbody fusion (MITLIF).

Methods: Between November 2011 to March 2013, 64 patients (24 males (38%) and 40 (63%) females, average age 63) underwent MITLIF. Pertinent patient characteristics along with administration of pre-operative and post-operative surveys for pain (Visual Analog Scale, VAS), life-function (Oswestry Disability Index, ODI), and the general physical and mental health summaries of the Short Form-36 (SF-36) were obtained.

Results: Average BMI was 29.55±6.59, with 66% of patients clinically obese. Diagnoses included bilateral foraminal stenosis (N=43, 67%) grade I spondylolisthesis (N=42, 65%), and spinal stenosis (N=33, 52%). MITLIF included L4-L5 level (N=40, 63%) or L5-S1 level (N=14, 22%) Average blood loss was 113.1±92.33, and there were no significant intraoperative complications. An average of 8.07±1.8 cc of autologous bone was harvested from the same surgical incision using the BoneBac Press. Novel interbody implant significantly increased postoperative disc heights (Mean=9.28mm, SD=1.8mm), as measured at most recent follow-up, compared to preoperative disc heights (Mean=5.86mm, SD=2.09mm), t= -15.45, p<0.001. Average hospital stay was 3.16±1.36 days, with a superficial post-operative infection rate of 6.7% and greater than 95% fusion rates. Paired T-test revealed statistically significant improvements in 4 patient outcome score comparisons: preoperative VAS (M=6.62, SD=2.33) vs. 2 week postoperative VAS (M=3.15, SD=1.63), t=5.052, p<0.001; preoperative VAS (M=6.8, SD=2.65) vs. three month VAS (M=3.93, SD=2.7), t=3.895, p=0.002; preoperative VAS (M=7.25, SD=2.66) vs. six month VAS (M=3.88, SD=2.64), t=2.48, p=0.042 (95% CL); and preoperative PCS (M=25.97, SD=7.6) vs. six month PCS (M=37.39, SD=10.26), t=-2.634, p=0.039 (95% CL).

Conclusions: These results indicate that MITLIF using the BoneBac Integrated Arthrodesis System improve clinical outcomes, fusion rates and limit complication rates.

Patient Care: To improve the adoption of minimally invasive spinal surgical fusion techniques by surgeons wishing to offer this treatment to their patients.

Learning Objectives: To learn about a novel minimally invasive arthrodesis system designed to facilitate minimally invasive spine fusion and reduce intra-operative complications while improving fusion rates and clinical outcomes.

References: Ogden, A.T., Fessler, R.G. (2010). Minimally Invasive Transforaminal Lumbar Interbody Fusion. Minimally Invasive Surgery in Orthopaedics, Chapter 69, 569-577. Shen, F.H., Samartzis, D., Khanna, A.J., Anderson, D.G. (2007). Minimally Invasive Techniques for Lumbar Interbody Fusions. Orthopedic Clinics of North America, 38, 373-386. Shunwu, F., Xing, Z., Fengdong, Z., Xiangquian, F. (2009). Minimally Invasive Transforaminal Lumbar Interbody Fusion for the Treatment of Degenerative Lumbar Diseases. Spine, 35, 1615-1620.