185 - Circumferential Fusion Achievable without Neurological Deficit Using B...

#185 Circumferential Fusion Achievable without Neurological Deficit Using Bilateral Transforaminal Lumbar Interbody Fusion Approach and a Low Profile, Expandable Interbody Device

Lumbar Therapies and Outcomes

Poster Presented by: P. Kiely

Author(s):

P.D. Kiely (1)
F. Taher (1)
C. Abjornson (1)
P.F. O'Leary (1)

(1) HSS, Integrated Spine Research, New York, NY, USA

Abstract

Summary: Circumferential 360 degree lumbar fusion may be achievable by a single posterior surgical approach, using the bilateral transforaminal lumbar interbody fusion (TLIF) approach to obtain interbody and posterolateral fusion in combination with a low profile, expandable and radiolucent lordotic interbody device (StaXx, Spinewave, Shelton, CT).

Introduction: Interbody fusion may be achieved posteriorly with either the posterior lumbar interbody fusion (PLIF) or transforaminal lumbar interbody fusion (TLIF). Radiculitis, neurogenic pain and an inability to extend fusions proximal to L3 have limited PLIF's versatility. Harms developed the unilateral TLIF approach to address these concerns, by accessing the disc space through the far lateral portion of the vertebral foramen. However, preparation of the opposite disc space through this unilateral approach is challenging, and maybe suboptimal. To rectify this problem, we modified this approach by performing bilateral TLIF. This modification created a bilateral paracentral transfacetal bony corridor through which we were able to safely introduce bilateral, low profile, expandable and lordotic interbody devices to correct sagittal and coronal imbalances while satisfactorily preparing the fusion bed.

Objective: To report our preliminary results using the bilateral TLIF approach and the low profile, expandable interbody fusion device.

Materials and Methods: The modified TLIF approach involved 1) standard posterior exposure of spine, with preservation of the spinous processes and attached ligaments, and placement of pedicle screws for distraction 2) Bilateral facetectomy, which facilitated decompression of the lateral recess 3) Incision and reflection dorsally of the PLL to protect the exiting nerve root 4) Distraction of the rod to fully facilitate the decompression of the lateral recess 5) An interbody fusion was performed through this narrow working channel following radical discectomy using expandable lordotic devices and bone graft 6) Posterior compression and lateral transverse process fusion.

Results: Forty five patients underwent this procedure in a single institution over an 8 month period, from March to November 2011. Thirty two (71%) patients were female, and 13 (29%) patients were male. The average age was 64 years (range 40- 86 years). Thirty eight (84%) patients underwent a single level interbody fusion (range 1-2). The L4/ L5 (53%) level was the most commonly involved, with the L5/S1 (27%) level the next most frequent. Bilateral cages were used in 43 patients (95%), with a mean expansion achieved of 11.4mm (9-15mm). Preoperatively, 11 patients (24%) had a sensorimotor deficit. Mean blood loss was 530ml/ patient (range 200-2000ml). Inpatient hospital stay was 6 days (range 3-16 days). Mean follow up was 9 months (range 7-15 months). Postoperatively, there were no cases of dural laceration, infection or neurological deterioration. All 11 patients with a preoperative sensorimotor deficit resolved spontaneously by 3 months. One patient required decompression of a more proximal stenosis, after developing new symptoms in the postoperative period Our preliminary clinical and radiological follow up data demonstrate satisfactory function and early fusion. No patients required revision surgery for implant subsidence, translation or removal.

Conclusion: The bilateral TLIF approach and low profile expandable devices may be an alternative posterior surgical technique to achieve balance and interbody fusion.