Clinical Investigations in Spine Fusion Surgery
Primary Investigator: Christopher D. Sturm, MD ,FACS
Study Coordinator: Virginia L. Snyder, PhD, PA-C
Spinal Fusion: The spine is comprised of a series of vertebrae that are separated by intervertebral disks, which act as ‘shock absorbers’ to help dissipate the load placed on the spine, as well as allowing for some flexibility of movement of the spine. When the disks fail to function properly, due to either degenerative changes to the disk itself, and/or bony elements of the spine, symptoms of pain or pressure manifest as a result of the alteration of the vertebral biomechanics.
The produced pain is typically caused by one or more of the following: the collapse
and micro-movement of the vertebrae in relationship to each other (due to loss of disk integrity), the friction generated by bony degenerative changes (also called spondylosis), and/or compressional forces placed upon structures, again as a result of the degenerative changes.
The goal of spinal fusion surgery is to create a bony fusion between vertebrae that exhibit the degenerative changes mentioned above. This is accomplished by surgically removing the deteriorated disk and placing a graft, or ‘cage’, into the disk space, which is then packed with bone graft material. The goal of the fusion process is to eliminate movement between the vertebrae, thereby eliminating, or limiting, pain. In some instances, the neurosurgeon is also able to address the bony degenerative changes during the procedure, in an attempt to ensure that there is adequate decompression of the nerves in the area.
Spinal fusion surgery has been utilized for a significant period of time, since the early 1960’s, to try to address both cervical and lumbar degenerative disk disease and spondylosis.
Over the years, there have been many different mechanical devices (cages) developed for use as the ‘spacer’ between vertebrae, whose function is to provide for fusion and stability.
Similarly, there are numerous options for bone graft material (used to pack the grafts or cages, to encourage bone growth and fusion). This may involve ‘autograft’, which refers to bone material harvested from the patient’s own hip, ‘allograft’, which is human donor bone,
or synthetic bone fusion materials. New devices are currently under clinical investigation, each attempting to provide superior opportunity for intervertebral fusion.
The Mercy Institute of Neuroscience is involved in several ongoing clinical research studies,
all of which are investigating new devices and/or packing materials for cervical and lumbar fusion. Two of these research trials are multi-centered, national, FDA-monitored studies:
the Coda™ Posterior Lumbar Interbody Fusion System, and the InFix™ Interbody Fusion System. Through radiological and physical evaluation, as well as patient questionnaires,
we are evaluating the clinical benefit of these devices in combination with different graft materials, and their success with lumbar fusion. The third study, an independent clinical trial under the direction of Dr. Christopher Sturm, MD, FACS, Neurosurgeon (Primary Investigator), is designed to collect clinical data on patients undergoing fusion for treatment of degenerative conditions of the cervical spine. In this study, the anterior cervical fusion is accomplished using a particular cage,
the Fortitude Device, manufactured in either titanium alloy, or a radiolucent PEEK material.
The cage is then packed with CERASORB™ β-tricalcium phosphate bone filler.
The following is a brief description of each of these studies:
Coda™ Posterior Lumbar Interbody Fusion
The Coda™ study includes patients that have a diagnosis of lumbar degenerative disk disease with posterior pathology, and are candidates for a posterior lumbar interbody fusion (PLIF).
The Coda™ study is designed to evaluate the safety and efficacy of the Coda™ Expandable Cage with pedicle screws vs. allograft (human donor bone) with pedicle screws, for this procedure.
This study involves randomly assigning patients into one of these two subgroups, and following the patients for a 24-month period, to include radiographical imaging, clinical evaluation and assessment, and patient data questionnaires.
Comparison of outcome data, through quantitative analysis, will provide invaluable information related to the use of the Coda™ device. This study is currently closed for enrollment, and is sponsored by Abbott Spine (formerly Spinal Concepts, Inc.).
InFix™ Interbody Fusion System
(Open ALIF with Autograft and Grafton® Demineralized Bone Matrix)
The Infix™ study includes patients who have a diagnosis of lumbar degenerative disk disease, but without clinically significant posterior pathology. The Infix™ device is a dynamic new type of cage utilized during an Anterior Lumbar Interbody Fusion (ALIF) procedure. The Infix™ device is implanted in all patients participating. The difference in this particular trial is the type of bone fusion material that is packed into the cage. Patients are, again, randomly assigned to one of two subgroups, one of which receives 100% allograft taken from the patient’s own hip. The other group receives a mixture of 50% autograft, and 50% Grafton® Demineralized Bone Matrix, which is an alternative bone graft material. This clinical trial evaluates the benefit of using the Infix™ cage with the autograft/Grafton® combination compared to the use of autograft exclusively within the cage (which has, historically, been used). The objective is to determine if this material will help decrease the amount of post-operative discomfort (related to the amount of bone taken from the hip, and resulting severe hip pain), while comparing the fusion status between the groups. Acquired radiographic, clinical, and patient survey data over a period of at least two years will provide the necessary material for comparative study. This study is also closed to enrollment, and is sponsored by Abbott Spine (formerly Spinal Concepts, Inc.).
CERASORB® β-TCP Contained within the Fortitude™ Device for Cervical Fusion
The purpose of this study is to surgically treat patients with cervical degenerative disk disease, by implanting a titanium or PEEK/Fortitude™ cage packed with Cerasorb® β-TCP bone fusion material, which is a new synthetic bone graft substitute.
Again, preoperative and postoperative radiographs, clinic evaluation and patient data questionnaires are completed,
and the data obtained can then be compared to other devices
and bone graft material, in terms of fusion success, and postoperative pain management (historically, the iliac crest harvest site is extremely painful for the patient).
All participants in the study will receive either a titanium or PEEK cage filled with Cerasorb®, are followed for a period of at least two years, and must meet certain inclusion/exclusion criteria to qualify for participation. Patients are still being enrolled in this clinical trial, and it is an independent study, under direction of
Dr. Christopher Sturm, MD, FACS. |
