San Francisco Spine Surgeons

Procedures San Francisco

Thoracic Compression Fracture

Thoracic compression fractures constitute very common pathology that we see at St. Mary’s Spine Center. The majority of thoracic compression fractures are in the mid-thoracic spine and lower thoracic spine—for example, around T7 or T8 level in the mid-thoracic spine, right at the apex of the thoracic kyphosis (normal thoracic curvature, as looking from the side). Also, down in the bottom, around T11 or T12, which is the lower part of the thoracic spine, we see those levels are fractured quite often as well. The thoracolumbar spine—which included T11, T12, L1, and L2 vertebrae—are at higher stress because of transition from the stiff thoracic spine, which is stiffened by the ribcage and sternum, and the very mobile lumbar spine. A lot of stress is being concentrated at this transition zone; therefore, quite a few fractures are seen around T11 and T12. The way to treat those fractures depends on the severity of pain and the patient’s presentation. If it is found incidentally, meaning on a radiograph or MRI done for a different reason, then usually the thoracic compression fracture can be ignored. If the patient comes into the office with moderate pain that can be controlled with simple medications and a brace, then we tend to observe this patient for a number of weeks or months. If the pain is severe and the patient is admitted to the emergency room or presents to the office but pain cannot be controlled by oral analgesics or bracing, then we consider surgical intervention. For a majority of osteoporotic compression fractures without significant compromise of the spinal canal, we can do a less invasive procedure with cement augmentation of the vertebra. We do utilize three distinct procedures—(1) vertebroplasty, when cement is injected into the vertebra through a large needle under x-ray guidance; (2) balloon kyphoplasty, similar to the above, but prior to the cement injection a balloon is inflated inside the vertebra, which partially lifts the collapsed vertebra and then creates a cavity, and then under the relatively low pressure the cavity is filled with the same bone cement. (3) The third procedure, which holds the most promise, is called KIVA. This involves placing a coil made out of a plastic called PEEK, which has the same stiffness and strength as that of normal bone. Once the PEEK coil is deployed, a small volume of cement is injected around the PEEK. The advantage of the KIVA procedure is similar to balloon kyphoplasty; it restores the vertebral body height, but the main difference is that instead of creating a stiff ball of cement, we create a relatively pliable ball of PEEK coil, inside of which there is a smaller volume of bone cement, so at least theoretically the advantage of the KIVA procedure is that the rate of adjacent-level fractures is decreased. The majority of KIVA procedures here at St. Mary’s are done by Dr. Ken Hsu, who has experience with hundreds of similar procedures and thousands of vertebroplasty procedures.

Thoracic Disc Herniation

Even though herniated disc is a common pathology we see in the cervical and lumbar spine, thoracic disc herniation is quite infrequent, at least in part due to the fact that the thoracic spine does not move much due to the rigidity offered by the ribcage. Having said that, we occasionally need to operate on symptomatic thoracic disc herniations. Because of the presence of spinal cord in the thoracic spine, approach to the thoracic disc herniations usually is dictated by the location of the herniation. Occasionally it is necessary to operate from the front, meaning going through the chest, to access safely the disc herniation. The main reason for that is that the spinal cord cannot be manipulated; therefore, if the thoracic disc herniation is not accessible from the back (posterior approach), either lateral or anterior approach is necessary to ensure neurological safety. Sometimes removing thoracic disc herniations necessitates concomitant fusion with placement of instrumentation and/or a cage. Occasionally, to safely access the disc herniation from the back, it is necessary to resect a section of the patient’s rib, usually on the side of the herniation. The rib that is harvested during the approach sometimes can be used for bone grafting to join two vertebrae together in the place where the disc herniated.

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.

Contact Us Today
to find out which Surgical Treatment might help you.

yelp yelp yelp Google+