Year: 2013

Is Minimally Invasive Spine Surgery Performed on the Neck?

Yes, minimally invasive spine surgery is an option for those with damage to the cervical spine (neck), as well as to those with injuries lower in the back. Patients with chronic neck pain who are not helped by conservative treatment may benefit from surgical treatment. Patients should consider surgery if they fail to improve with conservative therapy, have severe pain, weakness, cervical myelopathy, spinal cord dysfunction, spinal cord compression, and spinal cord swelling on an MRI scan. A discectomy is done to remove the disc compressing the nerves and spinal cord. The disc can be removed from through the front or back of the neck.

Most discs are removed through the front of the neck.  After the disc is removed a bone plug is inserted into the cleaned out disc space to hold the vertebrae apart. The vertebrae are then secured together with metal plates and screws.  Over time the two vertebrae and bone plug will fuse together.

New cervical neck endoscopes are being designed to remove the disc herniation without fusion and instrumentation. An endoscope is a micro video camera the size of a pencil which can be inserted through an incision the size of a fingernail. The camera then projects the images onto a video screen so the surgeon can easily visualize the disc compression.  Tiny instruments are inserted through the camera to decompress the nerve, which quickly provides relief from pain and suffering.

Cervical discs can be removed through the back of the neck.  The lamina in the rear of the spine is found and partially removed, exposing the disc that is pinching the nerve. The disc is then carefully removed.

New minimally invasive techniques allow this surgery to be done through a small tube inserted between the neck muscles, which decreases the muscle damage and weakness caused by muscle retraction. The disc and pinched nerve are found with the microscope and decompressed. The patient usually recovers quickly and without complication.

What is Spinal Stenosis?

Spinal stenosis is narrowing of the spinal canal.  This may be inherited, that is you were born with a small canal, or acquired, the spinal canal became smaller over time from degeneration, that is bulging discs, bone spurs and thickened ligaments.

As people age, the neck begins to “wear out”.  This begins with the drying out and collapse of the cervical discs.  This collapsed disc changes the forces across the spine and results in abnormal motion.  To stop this motion the body strengthens the neck by thickening the spinal ligaments and stabilizing the mobile joints with bone spurs.  This is especially seen behind the vertebral bodies, around the facet joints located at the side of the spine and in the ligamentum flavum (yellow ligament) at the back of the spinal canal.   These changes lead to decrease in the size of the spinal canal and may result in spinal cord compression.

Spinal stenosis may cause spinal cord injury and dysfunction called myelopathy. This may be due to compression, abnormal spinal motion or poor blood supply.   Myelopathy commonly presents in older people with neck pain, clumsy hands and difficulty walking.   This may be associated with pain, numbness, tingling, weakness, coordination problems (doing up buttons, fastening bra and eating), arm and leg stiffness, and bladder and bowel dysfunction.   People must rush to the bathroom to prevent incontinence.   Head movements may cause electrical shocks to shoot down their spine.   At times people may show slow decline in mobility:  from a cane to walker to wheelchair.  Very rarely, spinal stenosis can cause paralysis.

Endoscopic Treatment of Herniated Discs

Unfortunately, the spine suffers wear and tear as people age. This process is known as degeneration. Degeneration is usually first seen in the discs of adults in their thirties to fifties.  The annulus, the thick fibrous cartilage that surrounds the interior of the disc, may weaken. This allowing the nucleus that makes up the interior of the disc to overflow, which forms a bulging disc.  If the annulus tears, the nucleus may squeeze out forming a herniated disc. The disc may compress or “pinch” spinal nerves, causing the back and leg pain, numbness, tingling and weakness known as sciatica. This pain may be worsened or maintained by inflammation around the nerve roots in the spine.

Possible risk factors for ruptured discs are injury, smoking, pregnancy, jobs involving heavy lifting, repetitive lifting and twisting, or operation of heavy vehicles.

Patients who are not helped by more conservative treatment may benefit from surgery. Traditional surgery is destructive to the spine.  The larger the incision the more damage to skin, muscle, ligaments and bone. This collateral tissue damage may result in more pain, muscle weakness, spinal instability and scar tissue which could lead to future difficulties.

Minimally invasive surgery involves a skin incision of less than one inch, but it is more than just a small incision. The surgery is done through a tube that slides in between back muscles to decrease the muscle damage and weakness caused by muscle retraction.  As noted earlier, this is not the same as “microsurgery”, which only refers to surgery that involves the use of a microscope, not the size of the incision or the amount of muscle damage.

Endoscopic spine surgery is state-of–the-art minimally invasive spine surgery. During an endoscopic discectomy, a micro video camera is inserted through a very small incision to locate the disc that is pinching the nerve.  The camera projects the images onto a video screen so the surgeon can easily visualize the compression. Tiny instruments are inserted through the camera to decompress the nerve, relieving pain and suffering.  The advantages of this type of surgery include no general anesthesia, a very small incision, minimal post-operative pain, and a shorter recovery then traditional surgery.

The endoscopic discectomy is an excellent choice for someone suffering from recurrent disc herniation after traditional discectomy because it avoids most of the old scar tissue. This decreases the chance of spinal dural tears and spinal fluid leaks. Traditional discectomy is done through a midline incision.  A second surgery must deal with the scar tissue from the first operation, increasing risk of complications.  Endoscopic surgery is done from the side of the spine instead of the rear, avoiding most scar tissue and potential problems.

If you have been suffering from chronic back pain due to bulging or herniated discs, an endoscopic discectomy might help. Find out if you are a candidate for minimally invasive treatment by making an appointment today.

Relief of Annular Tears with Endoscopic Discectomy

The spine is made up of many bones called vertebrae. These vertebrae surround and protect the spinal nerves and lower part of the spinal cord from damage. Discs are located in between the spinal vertebrae and are made up of a tough outer shell called the annulus fibrosis and a soft spongy gel-like center called the nucleus pulposus. You can think of the disc like a jelly donut. The annulus is formed by many layers like “tape” stuck together.  The discs are named in reference to the spinal vertebrae. The disc between L4 and L5 vertebrae is called the L4-5 disc.  Similarly, the disc between L5 and S1 vertebrae is called the L5-S1 disc.

If too much stress is placed on the disc, the annulus – the outer shell – may rip, forming an annular tear.  There are three types of annular tears:

1.     Radial tears – A radial tear is a tear that goes all the way through the annulus, forming a channel connecting the inside to the outside of the disc.   The nucleus pulposus – the gel-like center of the disc – may extend into the tear and prevent it from healing. Radial tears are the most important annular tears because they often cause back pain. Back pain caused by injured discs is called discogenic back pain.  Radial tears may also cause leg pain by leaking inflammatory chemicals (such as tumor necrosis factor) from the nucleus pulposus onto spinal nerves.  This causes irritation and inflammation, resulting in pain.

2.     Concentric or circumferential tears – The wearing out of the annulus may lead to separation of the annular fiber layers like the layers of an onion, leading to weakening of the annulus. This results in a bulging of the disc.  Concentric tears do not usually cause back pain.

3.     Transverse tears – The tearing of the annulus’ connection to the vertebral body. These do not usually cause back pain.

Annular tears may be diagnosed on a work up for back and leg pain. They are seen as a white spot on MRI called a High Intensity Zone.  Discogram and CT scans best demonstrate annular tears and may indicate if it is the cause of a patient’s back pain.  Discogram is an interventional pain procedure done under X-ray guidance to determine which disc is causing pain.

Annular tears that are not successfully resolved with conservative treatment may be treated surgically. The treatment of annular tears must be individualized.  Unfortunately not every patient will be a candidate for surgical treatment.

Traditional surgery involves a large incision, muscle retraction and bone removal to expose the spine for disc removal and fusion.  This may be done through the abdomen [anterior lumbar interbody fusion(ALIF)], side [direct lateral interbody fusion (DLIF)] or back [posterior lumbar interbody fusion (PLIF) or transforaminal lumbar interbody fusion (TLIF)]. The spine is then held together with pedicle screws or clamps.  Today there are many minimally invasive options, from injections to endoscopic disc surgery and minimally invasive fusions.  The most promising new procedure appears to be endoscopic discectomy.

The endoscopic discectomy treats pain resulting from a torn disc by removing the painful disc with the annular tear.  This disc is found and removed through the endoscope, which provides rapid pain relief and a shorter recovery time than traditional back surgeries.