Interspinous process devices for treatment of degenerative lumbar spine stenosis: A systematic review and meta-analysis

Abstract

BackgroundDegenerative lumbar spinal stenosis is a condition related to aging in which structural changes cause narrowing of the central canal and intervertebral foramen. It is currently the leading cause for spinal surgery in patients over 65 years. Interspinous process devices (IPDs) were introduced as a less invasive surgical alternative, but questions regarding safety, efficacy, and cost-effectiveness are still unanswered.ObjectivesThe aim of this study was to provide complete and reliable information regarding benefits and harms of IPDs when compared to conservative treatment or decompression surgery and suggest directions for forthcoming RCTs.MethodsWe searched MEDLINE, EMBASE, Cochrane Library, Scopus, and LILACS for randomized and quasi-randomized trials, without language or period restrictions, comparing IPDs to conservative treatment or decompressive surgery in adults with symptomatic degenerative lumbar spine stenosis. Data extraction and analysis were conducted following the Cochrane Handbook. Primary outcomes were pain assessment, functional impairment, Zurich Claudication Questionnaire, and reoperation rates. Secondary outcomes were quality of life, complications, and cost-effectiveness. This systematic review was registered at Prospero (International prospective register of systematic reviews) under number 42015023604.ResultsThe search strategy resulted in 17 potentially eligible reports. At the end, nine reports were included and eight were excluded. Overall quality of evidence was low. One trial compared IPDs to conservative treatment: IPDs presented better pain, functional status, quality of life outcomes, and higher complication risk. Five trials compared IPDs to decompressive surgery: pain, functional status, and quality of life had similar outcomes. IPD implant presented a significantly higher risk of reoperation. We found low-quality evidence that IPDs resulted in similar outcomes when compared to standard decompression surgery. Primary and secondary outcomes were not measured in all studies and were often published in incomplete form. Subgroup analysis was not feasible. Difficulty in contacting authors may have prevented us of including data in quantitative analysis.ConclusionsPatients submitted to IPD implants had significantly higher rates of reoperation, with lower cost-effectiveness. Future trials should improve in design quality and data reporting, with longer follow-up periods.

Successful use of percutaneous interspinous spacers and adjunctive spinoplasty in a 9 year cohort of patients

“…Meyer et al found an 18.2% reoperation rate compared with 9.3% for laminectomy in 163 patients 6. Similar results have been shown by Stromqvist et al 9 (26% vs 6%, 100 patients), Moojen et al 23 (33% vs 8%, 211 patients), Beyer et al 24 (five out of 12 patients) and Lonne et al 25 (25% vs 4.9%, OR 6.5, 96 patients), and are supported by meta-analyses conducted by Honge et al 26 and Poetscher et al 10. This study concurs with an 11% rate of symptom recurrence in the PID only subgroup.…”

“…LSS is also a disease of the elderly who inherently carry a greater anesthetic risk. Minimally invasive and percutaneously inserted interspinous spacers have been shown to be both non-inferior in terms of patient outcomes and to have decisive benefits in terms of operating times and blood loss 2–26. This cohort of patients, the largest in a single study, confirms the existing cited literature which shows improvement in patient symptomatology and function after interspinous spacer insertion.…”

“…Beyond symptomatic improvement, there is evidence of diminution of LSCS and LSFS 7. The primary disadvantage when compared with conventional surgery is the incidence of device failure, symptom recurrence and reoperation, often related to either bony remodelling or spinous process fractures 8–10…”

“…Osteoporosis results in weakening and loss of height of both vertebral bodies and spinous processes 11 12. The position of a PID, between spinous processes, causes them to bear more weight and become prone to fracture 10. Augmentation of the spinous processes with polymethyl methacrylate (PMMA) serves to strengthen the underlying bone 11 12.…”

Percutaneous endoscopic ventral facetectomy: An innovative substitute of open decompression surgery for lateral recess stenosis surgical treatment?

“…[ 2 ] Degenerative LSS is associated with particular pathologic alterations in facet joints, posterior longitudinal ligament, or ligamentum flavum, alongside constituting a frequent disorder and the most banal indication for surgery in older adults. [ 3 4 ] LSS is traditionally classified into three different anatomic types: central stenosis (CS), lateral recess stenosis (LRS), or foraminal stenosis (FS), with particular clinical significance. [ 3 5 6 ]…”