421 - Allograft Cellular Bone Matrix in Extreme Lateral Interbody Fusion: Pr...

#421 Allograft Cellular Bone Matrix in Extreme Lateral Interbody Fusion: Preliminary Radiographic and Clinical Outcomes

Biologic Therapies

Poster Presented by: A. Tohmeh

Author(s):

A.G. Tohmeh (1)
B. Watson (2)
M. Tohmeh (1)
X.J. Zielinski (3)

(1) Northwest Orthopaedic Specialists, Spokane, WA, USA
(2) Inland Imaging, Radiology, Spokane, WA, USA
(3) Inland Imaging, Spokane, WA, USA

Abstract

Introduction: The extreme lateral interbody fusion (XLIF) procedure is a minimally-disruptive alternative for anterior lumbar interbody fusion. Recently, synthetic and allograft materials have been increasingly used to eliminate donor-site pain and complications secondary to autogenous bone graft harvesting. The clinical use of allograft cellular bone graft has potential advantages over autograft by eliminating the need to harvest autograft while mimicking autograft's biologic function. The objective of this study was to examine 12-month radiographic and clinical outcomes in patients who underwent XLIF with Osteocel Plus, one such allograft cellular bone matrix.

Methods: Clinical and radiographic data were collected through a prospective registry of XLIF patients from a single institution. Inclusion criteria included having Osteocel Plus as the sole bone graft material with at least 12 months follow-up with computed tomography or fluoroscopy-guided, level-by-level, radiography assessed by a third party reviewer to determine extent of bony fusion in XLIF levels.

Forty (40) patients met inclusion criteria. Mean age was 60 years, 13% were smokers, and 65% had undergone prior lumbar spine surgery. 68 total levels were treated in 40 patients between L1-S1. Of these, 61 were XLIF and 7 at L5-S1 were TLIF.

Results: No complications were observed. One patient underwent reoperation at an adjacent level for degeneration. From preoperative to 12-months postoperative, ODI improved 41% (45.7 to 27.1), LBP improved 55% (7.4 to 3.4), leg pain improved 43.3% (6.8 to 3.8) and QOL (SF-36) improved 56% (41.8 to 65). At 12-months 92% reporting being “very” or “somewhat” satisfied with their outcome and 86% being either “very” or “somewhat likely” to choose to undergo the procedure again.

Complete fusion was observed in 90.2% (55/61) of XLIF levels. Six (9.8%) levels were assessed as having progressing fusion, where ossification was present in the cage, but complete trabecular bridging was not yet observed. No levels were assessed as indeterminately fused, or showing lucencies at endplates with or without ossification in the cage. Evidence of any (≥1mm) radiographic subsidence was observed in 20 of 61 levels (32.8%), though was not clinically relevant and did not inhibit fusion.

Conclusions: This work represents the first report, to our knowledge, of fusion rate outcomes follwoing the use of allograft cellular bone matrix in the human spine. Complete interbody fusion with Osteocel Plus was shown in 90.2% of XLIF levels, with the remaining 9.8% being partially consolidated and progressing towards fusion at 12 months.