Outcome Measures of an Intracan, Endoscopic Transforaminal Decompression Technique

Presented at SMISS Annual Forum 2013
By Joseph A. Sclafani MD
With Kamshad Raiszadeh MD, Choll W. Kim MD, PhD,

Disclosures: Joseph Sclafani MD None Kamshad Raiszadeh MD None, Choll Kim MD, PhD None,

Introduction: Intradiscal endoscopic procedures achieve decompression through indirect techniques. More recently developed intracanal endoscopic procedures (IC) utilize a more lateral transforaminal approach to allow decompression under direct visualization of the spinal canal. This study is an assessment of IC outcome data obtained through sub-analysis of the MIS Prospective Registry.

Methods: Analysis was performed on the MIS Prospective Registry database containing 485 patients. A subgroup of patients treated with the endoscopic IC technique was identified. Statistical analysis was performed using paired t-tests (p<0.05).

Results: A total of 86 IC patients with a median age of 49 years (range 18-89 years) were analyzed. Median hospital stay was 0 days. There were no intraoperative complications. Overall ODI scores of the patient subgroup who had reached the one year post-operative time point were 41.5 pre-op (n=46), and 28.4 at one year post-op (n=35, p=0.001). There was significant VAS score improvement in the one year post-operative patient group: pre-operative VAS (back=5.5, leg=5.1, n=46), and one year post-op (back=3.1, leg=1.8, n=35, p=0.002). A sub-analysis of IC patients with two distinct primary diagnoses was performed. Group IC-1 underwent treatment for disc herniation with radiculopathy (n=29). The primary indication for group IC-2 was neuroforaminal stenosis (n=10). Group IC-1 (disc herniation) showed improvement in ODI (18.4 points, p=0.001, n=29) and VAS (back=1.7 points, leg =3.8 points, p=0.001, n=29) scores starting 6 weeks post-op. Group IC-2 (foraminal stenosis) showed VAS score improvement (back=3.7 points, leg =6.4 points, p=0.05, n=10) starting 6 weeks post-op but no significant ODI improvement at any time point. One year re-operation rate was 1.8% for group IC-1 and 33% for group IC-2.

Conclusions: The initial results of the MIS Registry IC subgroup (intracanal, transforaminal endoscopic lumbar surgery) show a significant clinical improvement when the technique is employed to treat patients with lumbar disc herniation. The treatment of foraminal stenosis can lead to improved short term clinical outcome but is associated with a high re-operation rate at 1 year post-op. The long-term outcomes, together with higher level analysis of cost-effectiveness (cost/quality adjusted life year) will be forthcoming with the continued growth of the MIS Registry database.