Cervical Spine Stenosis
Laminoplasty was first performed by hinging the bone open and holding it in place with a piece of bone taken from another location. This piece of bone would be held in place by a small metal plate bent to the correct position by the surgeon. The goal with this would be for the bone that was holding the gap open to heal across. However with advancements in technology and understanding of outcomes there has been the development of special plates that hold the bone open at the ideal angle to allow for increased room for the spinal cord.
Additionally, it has been determined that patients do extremely well with this procedure even if there is not a bony bridge holding the gap open, as the plate provides sufficient strength. Additionally, there is decreased operative time, faster recovery as the patient does not have to wait for the bone bridge to heal, and mitigate the risk of morbidity at another operative site for bone harvest.
Treatment of cervical stenosis is by decompression, meaning relieving the pressure on the spinal cord and/or nerve root. This is done most often done through an anterior or posterior approach to the spinal cord depending on where the compression is coming from. An anterior approach is used when the intervertebral disc is the etiology of compression. A posterior approach is used for most other causes of cervical stenosis, as it allows for better removal of bone or soft tissues that may be constricting the spinal cord.
Often the bone on the back of the vertebra can be removed carefully opening up the space around the spinal cord and relieving the pressure. However, with removal of the posterior bone from the vertebra this can destabilize the spine requiring a fusion to be performed. Fusions are performed by placing screws into the vertebral body from the back of the neck and connecting them with metal rods. This effectively removes all motion between levels.
New techniques have been developed however that relieve compression of the spine without causing instability and therefore do not require fusion. The most popular of these is laminoplasty. With this technique, the posterior bone is not removed, but manipulated similar to opening a door partially to allow for increased room within the spinal canal. The “open door” is held in place with either a small metal plate or a piece of bone.
Cervical Spine Stenosis
Cervical spinal stenosis is a diagnosis that means the spinal canal in the neck is decreasing in area or getting tight. This can cause impingement onto the spinal cord itself or on to the nerve roots that are coming off of the cord. This is usually due to hypertrophy, or increased size, of the ligaments within the spinal canal, bulging of the vertebral disc, or hypertrophy of the small joints of the back of the spine. Symptoms of cervical spinal stenosis include neck pain, difficulty with fine motor skills (button a shirt or picking up keys), and can affect balance and gait. These symptoms do not often improve without surgical intervention.
DePuy Synthes MOUNTAINEER™ Laminoplasty Spine System has designed the ideal plate for the laminoplasty procedure. The system has been designed for ease of surgeon use, with multiple configurations of plates to better match patient anatomy, and allows for increased stability with the ability to supplement with redundant fixation and bony augmentation. The procedure is done through a posterior midline approach to the cervical spine. This implant allows the maintenance of neck motion without the risk of instability while effectively relieving pressure on the spine.