Coflex Device Shows ‘Similar or Superior’ Efficacy to Fusion When Used With Decompression in 5-Year Study of Lumbar Spinal Stenosis
Commentary by Lead Study Author, Michael J. Musacchio, MD and SpineUniverse Editorial Board Member, Lali Sekhon, MD, PhD, FACS, FAANS
Decompression plus interlaminar stabilization with coflex® (Paradigm Spine, LLC) produced similar outcomes to decompression plus fusion with pedicle screws in the treatment of lumbar spinal stenosis, according to 5-year data from a prospective, randomized, controlled trial published in the International Journal of Spine Surgery.
The findings “confirm that coflex interlaminar stabilization is a validated and durable treatment option for patients with moderate to severe lumbar stenosis with back and leg pain and up to Grade I spondylolisthesis,” said lead author Michael J. Musacchio, MD, neurosurgeon at NorthShore University HealthSystem, Evanston, IL.
“When considering the traditional treatment options for lumbar stenosis, patients are commonly faced with the potential for under-treatment with laminectomy alone or over-treatment of laminectomy and fusion,” Dr. Musacchio said. “The coflex® device offers a non-fusion alternative to stabilization that is shown to provide the benefits of fusion without the drawbacks, including a less invasive procedure with shorter recovery times, less adjacent level disease, maintenance of foraminal heights, and lower costs.”
Multicenter, Randomized Controlled Study
The study included patients (ages 40 to 80) with moderate to severe lumbar stenosis at 1 or 2 contiguous levels and up to Grade I spondylolisthesis who were randomized to decompression and interlaminar stabilization (D+ILS; n=215) using the coflex® device or decompression and fusion with pedicle screws (D+PS; n=107). The patients were treated at 21 sites in the United States. More than 90% of patients completed the 5-year study.
At baseline, the patients had a minimum Oswestry Disability Index (ODI) score of at least 40%; and a visual analogue scale (VAS) back pain score of at least 50 of 100.
The following composite success criteria was used:
- >15 point improvement in ODI score
- no reoperation, revision, removal, or supplemental fixation
- no major device-related complication
- no epidural steroid injection after surgery
Treatment Success Found in Approximately Half of Each Group
As shown in the Table, a similar proportion of both groups reached the composite success criteria at 5 years (50.3% and 44% of the D+ILS and D+PS groups, respectively; P>0.35). In addition, the rate of reoperation/revision was similar in the two groups (16.3% vs 17.8%, respectively; P>0.90). Furthermore, both groups showed significant improvement in ODI scores throughout the 5-year study.
Similarly, scores on the VAS, Short Form-12, and Zurich Claudication Questionnaire (ZCQ) were significantly improved in both groups at 5 years, with a significantly greater improvement in ZCQ score found in the D+ILS group (P<0.01). Preoperative foraminal height, disc space height, and range of motion at the index level were maintained through 5 years in the D+ILS group.
“The results provide patients and physicians alike the data to support the use of coflex® after laminectomy in patients with degenerative spinal stenosis that involves mechanical back pain and segmental degeneration with the potential for recurrent disease as an alternative to fusion,” Dr. Musacchio said. “Fusion is still typically required for patients with gross spinal instability or deformity, but many patients with stenosis fall short of this extreme and will benefit from the less invasive, non-fusion stabilization that coflex® offers.”
“The contraindications for use of coflex® include presence of an unstable spondylolisthesis, scoliosis greater than 25 degrees, osteoporosis, and previous laminectomy or fusion at index level,” Dr. Musacchio explained.
“The study showed equivalence between decompression with coflex® implantation and decompression and instrumented fusion at the 5-year period,” commented Lali Sekhon, MD, PhD, FACS, FAANS a neurosurgeon with Sierra Neurosurgery Group in Reno, NV, and Adjunct Associate Professor, Department of Physiology and Cell Biology, at the University of Nevada, School of Medicine in Reno and Las Vegas.
Dr. Sekhon noted that the findings do not refine the indications for the procedure and suggested the need to compare use of D+ILS to use of D+PS in patients with true instability. In addition, Dr. Sekhon wondered how many patients in this study might have been successfully treated with decompression alone.
“As a surgeon, I am most interested in coflex® alone versus decompression. Stable small spondylolisthesis can do well with a simple decompression with good clinical outcome,” said Dr. Sekhon, who is a member of the SpineUniverse Editorial Board.
Coflex® Is Designed to Address Segmental Deterioration
“Use of coflex® should be considered more as a procedure than a device,” Dr. Musacchio concluded. “Lumbar stenosis is a chronic, progressive disease that causes more impairment than just nerve impingement. Laminectomy alone addresses neural compression, but often fails at addressing the totality of the stenotic disease state. Coflex® is intended to address the segmental degeneration that contributes to stenosis and often causes mechanical back pain, disease of the facets, and the potential for recurrent disease after decompression.”