Cervical
Procedures San Francisco

Occipitocervical Fusion for Upper Cervical Instability

This is done for problems in the upper cervical spine, usually involving the occiput, C1, and C2, sometimes for instability at the occiput-C1 junction or atlantoaxial instability. Sometimes this is due to trauma; in other cases, this is due to inflammatory conditions such as rheumatoid arthritis. In general, this is quite similar to posterior cervical laminectomy and fusion with the exception that the procedure is taken all the way to the skull. A small plate is inserted onto the occipital part of the skull and held in place with short screws. Then, several screws are inserted, usually around the C2 vertebra, also known as the axis. Sometimes it is necessary to place fixation below C2 as well for added stability; those are connected with rods. A bone graft is added around the instrumentation to promote solid fusion (mending of several bones together). The procedure usually takes anywhere from two to four hours. Postoperatively, sometimes a brace is utilized, though in some cases it is not necessary. The hospital stay after occipitocervical fusion is anywhere from three to seven days.

Posterior Cervical Laminectomy and Fusion

Posterior cervical laminectomy and fusion allows both decompression of multiple levels of the cervical spine all at once through a posterior approach (going from the back of the spine) as well as stabilization of the cervical spine. Based on available clinical evidence, standalone laminectomy of the cervical spine usually is not advocated because of concerns about postoperative stability at the cervical spine. Therefore, whenever multilevel decompression of the neck is required from the back, usually stabilization is recommended. The stabilization is performed usually with the assistance of small titanium cervical screws that are inserted into part of the vertebra that is called the lateral mass. The surgery usually takes four to six hours and is done across multiple segments. During the surgery, frequently a surgical microscope is utilized, and in cases of severe spinal cord compression, we do utilize neurological monitoring. Postoperatively, occasionally patients need a cervical collar, either a soft or hard collar, depending on the situation. The hospital stay for a case like this typically is anywhere from three to seven days.

Spinal Cord Stimulator

Spinal cord stimulator belongs to neuromodulation, an evolving field in cranial and spinal surgery. It is a tool that is used for control of chronic pain and unpleasant sensation in both upper and lower extremities. Occasionally it is a tool that is used for pain control after prior spinal operations have failed (so-called failed back syndrome). Sometimes it is used for intractable neuropathy, such as diabetic neuropathy or post-radiation or post-chemotherapy neuropathy. It is also used for damaged nerves and a condition called RSD (reflex sympathetic dystrophy), also known as CRPS (complex regional pain syndrome). Thoracic spinal cord stimulator procedure can be done on an outpatient basis and involves performing laminectomy in the thoracic spine (unroofing of the spinal canal) usually done in the lower part of the thoracic spine anywhere from T8 down to T12. Then, electrodes are placed within the spinal canal, outside the spinal cord. A separate battery, similar to that used for pacemakers, is implanted, usually in the buttock subcutaneous, meaning under the skin, or around the flank. At the completion of the procedure, the paddle with the actual electrodes in the thoracic canal is connected to the battery in the buttock via tunneling. Postoperatively, the patient uses a remote control to control the specific programs that dictate the frequency of electrical discharges, amplitude, and so forth. Spinal cord stimulators operate based on what is called gate theory; however, the exact mechanism of action is not known. The majority of spinal cord stimulators create so-called paresthesias or sensations of pins and needles, which overwhelms the sensation of pain. Prior to the placement of the spinal cord stimulator, patients go through what is called a trial procedure, which involves a pain management physician placing little wires (percutaneous leads) through a large needle into the spinal canal. The procedure is quite similar to an epidural injection; however, instead of injecting steroid into the spinal canal, an electrode is being placed. The externalized part of the electrode is connected to a battery, and the trial usually takes place over the course of two to five days, when the patient gets to “test drive” the stimulation and see if that is something that benefits his or her pain. If the patient finds that the pain is significantly decreased, sensation of pins and needles was not unpleasant, and function overall has improved, as well as the intake of pain medications decreased, then the trial is deemed to be successful. After this, the patient is referred to a spine surgeon for the placement of a permanent system. Spinal cord stimulation can be done in the thoracic spine and the cervical spine, depending on the patient’s needs.

Posterior Cervical Spine Surgery

Key Points

Posterior cervical spinal approaches to provide relief of upper extremity pain, numbness, and weakness include: laminotomy, foraminotomy, laminoforaminotomy, hemilaminectomy, bilateral laminectomy, and laminoplasty. Preoperative patient positioning must be done carefully. Then the posterior cervical spine is exposed (Figure1)

Cervical radiculopathy is often caused by disc herniation compressing the nerve root (Figure 2).

Laminoforaminotomy is performed to remove parts of the superior and inferior laminae at the level of the nerve root compression (Figure 3).

Partial facetectomy is performed carefully so that no more than half of the facet joint is removed. The nerve root is gently retracted and discectomy performed (Figure 4).

Hemilaminectomy (Figure 5) can be performed for radiculopathy when symptoms are unilateral.

Bilateral laminectomy (Figure 6) can be performed for central spinal stenosis when radiculopathy is bilateral.

Multilevel laminectomies can be performed when the cervical lordosis is preserved. Cervical laminectomy can result in postoperative instability and kyphosis. This is more common when multilevel laminectomies are performed and in younger patients. Disruption of the facet joints leads to higher rate of instability and deformity.

Cervical laminoplasty was first developed in Japan to treat spinal stenosis related to ossification of the posterior longitudinal ligament (OPLL). Laminoplasty can prevent postlaminectomy kyphosis and instability.

Various laminoplasty techniques were developed, including: unilateral open door (Figure 7), open door with suture (Figure 8-1), open door with bone graft (Figure 8-2), open door with small titanium plates and screws (Figure 8-3), and midline open door or French door laminoplasty with bone graft (Figure 8-4).

In laminoplasty, the lamina is cut on both sides, cut through completely on one side and partially on the other side, which is then used as a hinge. The freed flap of the lamina is lifted away to relieve pressure on the spinal cord (Figure 7). The lamina is then propped open with suture, bone graft, and small titanium plates and screws (Figures 8-1 through 8-3). Laminoplasty is performed to relieve pressure on the spinal cord from spinal stenosis resulting from different causes, including ossification of the posterior longitudinal ligament (OPLL), spinal tumors, spinal cord cyst, and syringomyelia. Laminoplasty is contraindicated when there is kyphotic deformity, significant instability, or when the spinal condition is best approached anteriorly as in disc disease, such as disc herniation or fracture.