Asian Spine J.  2016 Feb;10(1):27-37. 10.4184/asj.2016.10.1.27.

Lumbar Interspinous Process Fixation and Fusion with Stand-Alone Interlaminar Lumbar Instrumented Fusion Implant in Patients with Degenerative Spondylolisthesis Undergoing Decompression for Spinal Stenosis

• Postacchini F
• Postacchini R
• Menchetti
• Sessa P
• Paolino M
• Cinotti G

• KMID: 2169277
• DOI: http://doi.org/10.4184/asj.2016.10.1.27

Abstract

STUDY DESIGN: Prospective cohort study. PURPOSE: To assess the ability of a stand-alone lumbar interspinous implant (interspinous/interlaminar lumbar instrumented fusion, ILIF) associated with bone grafting to promote posterior spine fusion in degenerative spondylolisthesis (DS) with vertebral instability. OVERVIEW OF LITERATURE: A few studies, using bilateral laminotomy (BL) or bilateral decompression by unilateral laminotomy (BDUL), found satisfactory results in stenotic patients with decompression alone, but others reported increased olisthesis, or subsequent need for fusion in DS with or without dynamic instability.
METHODS
Twenty-five patients with Grade I DS, leg pain and chronic low back pain underwent BL or BDUL and ILIF implant. Olisthesis was 13% to 21%. Follow-up evaluations were performed at 4 to 12 months up to 25 to 44 months (mean, 34.4). Outcome measures were numerical rating scale (NRS) for back and leg pain, Oswestry disability index (ODI) and short-form 36 health survey (SF-36) of body pain and function.
RESULTS
Fusion occurred in 21 patients (84%). None had increased olisthesis or instability postoperatively. Four types of fusion were identified. In Type I, the posterior part of the spinous processes were fused. In Type II, fusion extended to the base of the processes. In Type III, bone was present also around the polyetheretherketone plate of ILIF. In Type IV, even the facet joints were fused. The mean NRS score for back and leg pain decreased by 64% and 80%, respectively. The mean ODI score was decreased by 52%. SF-36 bodily pain and physical function mean scores increased by 53% and 58%, respectively. Computed tomography revealed failed fusion in four patients, all of whom still had vertebral instability postoperatively.
CONCLUSIONS
Stand-alone ILIF with interspinous bone grafting promotes vertebral fusion in most patients with lumbar stenosis and unstable Grade I DS undergoing BL or BDUL.

Keyword

Lumbar spine; Degenerative spondylolisthesis; Lumbar stenosis; Laminotomy; Interspinous fusion

MeSH Terms

Bone Transplantation
Cohort Studies
Constriction, Pathologic
Decompression*
Follow-Up Studies
Health Surveys
Humans
Laminectomy
Leg
Low Back Pain
Outcome Assessment (Health Care)
Prospective Studies
Spinal Stenosis*
Spine
Spondylolisthesis*
Zygapophyseal Joint