Extreme Lateral Interbody Fusion For Unilateral Symptomatic Vertical Foramincal Stenosis

Presented at SMISS Annual Forum 2014
By Marjan Alimi MD
With Christoph Hofstetter MD, PhD, Roger Härtl MD, Eric Elowitz MD, Apostolos Tsiouris MD,

Disclosures: Marjan Alimi MD None. Christoph Hofstetter MD, PhD , Roger Härtl MD B; Brainlab, DePuy-Synthes, Ulrich, Eric Elowitz MD B; NuVasive, Apostolos Tsiouris MD None,

Introduction:
Spinal deformity of the adult lumbar spine may occur de novo due to degenerative disease or following decompressive surgery. Asymmetric loss of disc height may lead to unilateral vertical foraminal stenosis and radiculopathy.

Aims/Objectives:
The current study aimed to investigate whether restoration of foraminal height at the symptomatic level using single-level extreme lateral interbody fusion (ELIF) may alleviate unilateral radicular pain.

Methods:
In a retrospective cohort study, patients with single level unilateral vertical foraminal stenosis (foraminal height < 15 mm) and corresponding unilateral radicular pain who underwent ELIF were included. Demographic and peri-operative data were collected. Functional data (Visual Analoge Scale (VAS) for buttock, leg and back, as well as Oswestry Disability Index (ODI)) and radiographic measurements (bilateral foraminal height, disc height, segmental coronal cobb angle and regional lumbar lordosis) were collected pre-operatively, postoperatively and at the last follow-up.

Results:
A total of 23 patients with a mean age of 66 years were included. The foraminal height of stenotic side was significantly increased by ELIF from the pre-operative value of 11.0 mm to 18.1 mm post-operatively (p<0.001). The increase was durable at last follow-up of 11 ± 3.7 (SE) months (17.1 mm; p<0.001). Preoperative VAS buttock and leg on the stenotic side, VAS back, and the ODI (7.3, 7.2, 6.5 and 48.0, respectively) were significantly improved postoperatively (1.5, 2.3, 3.3 and 25.4, respectively) and at the last follow-up (to 0.7, 1.1, 3.3 and 23.0).

Conclusions:
Single-level ELIF is an effective procedure for treatment of symptomatic unilateral vertical foraminal stenosis.