Microdiscectomy

Microdiscectomy is the most common surgical procedure used to relieve leg and/or back pain. During this procedure, a small portion of the vertebrae, the lamina, is removed, giving access to the nerves and disc. The portion of the disc is removed, relieving pressure on the nerve root.

During the surgery, a small incision is made in the center of the back; the length depends on the number of levels to be explored. After removing the disc, the incision is closed with stitches under the skin or with staples.

Patients are usually asleep for the procedure. Typically an overnight admission is usually necessary. The surgery takes about 1 hour.

Decompressive Laminectomy

Decompressive laminectomy is a surgical procedure used to remove pressure on the spinal canal and spinal nerves. Removal of bone, ligament, and disc may all be involved.

The incision is made in the center of the back. A temporary drain may be placed beneath the incision.

Surgery may take 1 to 3 hours with a hospital stay of 1 to 2 days.

Fusion

The spine is a flexible column made up of separate bones called vertebrae. Between each vertebra is a round, tire-shaped structure called an intervertebral disc. The outer ring of the disc is made of fibrous tissue and functions as a ligament. The center of the disc is gel-like and functions as a cushion or shock absorber.

Degeneration, herniation, or rupture of the intervertebral discs of the spine is a leading cause of disability, activity limitation, and economic loss. Degeneration of the cervical discs causes neck pain, and if the nerve roots are compressed, pain can be felt in the shoulder, arm, and hand. Degeneration of the lumbar discs causes back pain. If the nerve roots are compressed, pain can be felt in the buttock or leg. Nerve pressure can also cause numbness or weakness.

Initial treatment of damaged discs in the spine emphasizes medical and physical methods. Anti-inflammatory medications, muscle relaxants, and pain pills often relieve intermittent episodes of pain. Physical therapy including traction, ultrasound, hot packs, or exercises are often beneficial.

If the pain and disability remain severe and disabling after six weeks or more of medical treatment, then surgery may be considered. Surgery can be considered if the problem initially improves but returns frequently and is troublesome or a constant annoyance.

Cervical Fusion

The most common surgery to treat damaged discs in the neck is a fusion operation done in the front of the neck. This is called an anterior cervical fusion. In this operation, the worn out disc is completely removed and replaced with bone graft strong enough to support the vertebral bones. The bone graft is usually taken from the front of the pelvis or hip area. When the bone heals, the pain and disability are usually relieved.

Anterior cervical fusion is successful in achieving fusion (bone healing) in about 85% of cases and is successful in relieving pain and disability in about 90% of cases.

Unfortunately, removal of the block of bone from the hip area results in long standing hip pain in up to 20% of patients. Additionally, if the bone graft is not strong enough to support the patient's weight, the graft may crumble and heal in an abnormal position.

Beginning in 1985, Dr. John W. Brantigan designed a group of spine implants called "cages". These implants are made of a carbon fiber reinforced polymer material that is light in weight and very strong. The cages have hollow areas that are filled with a patient's own bone. Although this bone is taken from the hip area, it is taken through a smaller incision and does not require removal of a large block of bone.

This cage was found to be very successful in achieving bone fusion and provided better improvement in pain and function than previous methods in treating the problems studied. Very few patients reported discomfort from taking bone graft.

Compared with traditional fusion operations, the Cervical I/F Cage has the following potential advantages:

1.) The frequency of long-standing pain from the hip may be reduced.

2.) The frequency of collapse of the disc area may be reduced.

3.) The alignment of the vertebral bones may be improved.

4.) The rate of fusion success and relief of pain may be improved.

The Cervical I/F Cage has been used in Europe since about 1995. Initial results indicate that the implant is performing to expectations. However, the exact success rate and the nature and frequency of complications are not known.

A posterior cervical fusion uses an incision in the back of the neck. Fusion is accomplished by placing bone graft across the bones to be fused. At the same time, pressure on nerves may be relieved by removing a small piece of bone which lies over the nerve. These fusions may be strengthened with either wires or metal plates and screws.

Patients are asleep for these procedures. After completing the procedure, a small temporary drain may be placed underneath the incision. A collar is worn to hold the neck steady and provide support.

The surgery typically takes 2 to 3 hours. Patients should be able to get out of bed for short periods of exercise shortly after surgery. A hospital stay of 1 to 2 days may be required.

Lumbar Fusion

The most common types of fusion in the lower back are posterolateral fusion (PLF) and interbody fusion. Interbody fusion can be done from the back (posterior lumbar interbody fusion or PLIF), or can be done from a front incision (anterior lumbar interbody fusion or ALIF).

In the posterolateral fusion operation, bone graft is placed external to the disc to cause the spinal bones to grow together. This is the simplest type of fusion surgery, but it may not relieve back pain because it does not remove the damaged disc. Screws and plates or rods may be added to increase stability. The procedure is done to relieve back pain and to add strength and stability to the lumbar spine.

In the Posterior Lumbar Interbody Fusion operation (PLIF), the entire disc is removed, and bone graft is placed inside the disc space. The bone graft may be taken from the bone bank (transplant bone), or a patient's own bone may be used from the back of the pelvis or hip area.The bone graft must be strong enough to support the patient's body weight. When the graft bone heals, the pain and disability are usually relieved because solid bone takes the place of the painful disc. If the bone graft is crushed by the patient's own weight or if the bone fails to heal, the pain and disability may actually get worse.

Lumbar I/F Cage

An anterior lumbar interbody fusion is a surgical procedure in which the lumbar spine is fused by removing one or more of the lumbar discs. The disc is replaced with a piece of the patient's bone or donor bone or fusion cages. The procedure is done to relieve back pain and to add strength and stability to the lumbar spine.

Compared with the traditional fusion operations, the Anterior I/F Cage has the following potential advantages:

1). The frequency of long-standing pain from the hip may be reduced.

2). The frequency of collapse of the disc area may be reduced.

3). Because a large oval cage may be more stable than side-by-side cages or bone grafts, surgery may be successful without the need for metal screws and plates.

4). Because the surgeon does not work around the spinal nerve roots, nerve pain after surgery may be reduced.

The Anterior I/F Cage has been used in Europe since about 1995. Initial results indicate that the implant is performing to expectations. However, the exact success rate and the nature and frequency of complications are not known.

In an anterior lumbar fusion, an incision is made in the abdomen to expose the front part of the spine. The exposure and closure is usually performed by a peripheral vascular surgeon or general surgeon. A temporary drain may be placed beneath the incision. It may be necessary to wear a brace or corset. The surgery may take 2-3 hours with a hospital stay of 2 to 3 days.

Scoliosis

Scoliosis is a condition when the spine is curved. Surgery may be needed to correct the spinal curvature.

Procedures to correct scoliosis are tailored to the patient's curve. Surgery may be from the front, back or a combination of both. Once the curve is corrected, it is held in place using a system of rods, screws and wires. Bone graft is used to help the fused portion of the spine solidify.

The surgery may take anywhere from 4 to 12 hours. Recovering in the hospital can take several days.

With age, or due to injury, cracks, or fissures may develop in the wall of the intervertebral disc. Filled with small nerve endings and blood vessels, these fissures are a chronic source of pain in many patients. Additionally, the inner disc tissue (nucleus) will frequently bulge (herniated) into these fissures in the outer region of the disc, likewise stimulating pain sensors within the disc.

Nucleoplasty

Back problems are among the most common ailments affecting adults, and are potentially one of the most debilitating. For most people, back problems resolve quickly, aided by rest, therapeutic exercise, or medication. For some however, back problems resulting from disc herniation are prolonged and severe, and do not respond to conventional treatments.

Nucleoplasty is a minimially invasive procedure developed for patients with contained herniated discs. In the Nucleoplasty procedure, the physician removes tissues and applies controlled levels of thermal energy (heat) to the disc.

Nucleoplasty is usually performed on an outpatient basis. Local anesthesia and mild sedation may be used to reduce discomfort during the procedure. You will be awake to enable you to provide important feedback to your physician. With the guidance of X-ray images, your physician will first advance a needle into the disc. A specialized device, known as the Perc-D SpineWand, will then be introduced through the needle and into the disc. Nucleoplasty consists of creating a series of channels in your disc and then thermally treating the tissue immediately adjacent to the Perc-D SpineWand. The procedure should take less than an hour.

The first type of artificial disk was approved by the FDA in October 2004. This is the CHARITE artificial disk from Depuy Spine, Inc. this is a significant new implant in the modern treatment of spinal problems. The disk replacement is the first motion preserving implant. The disk replacement has a high density low friction polyethylene spacer between 2 metal endplates. The design is similar to that of hip and knee replacement.

The artificial disk may offer several theoretical benefits over spinal fusion for treatment of chronic low back pain in carefully selected patients.

• Potentially a higher rate of clinical success.

• Potentially avoid adjacent segment deterioration

TDR Helping quality-of-life.

Disc replacement may help those who have suffered for years with disabling low back pain. Presently, Spinal fusion has been the treatment for disabling low back pain. The long term results may be similar between the two methods.

What will be one person’s outcome with TDR.

A person must be careful, because not everyone can expect to become normal again. The FDA study with two-year follow-up showed that while the disk replacement patients had similar function of daily living, pain, and satisfaction as the corresponding fusion patients, neither group was completely relieved of their pain. 14% of disk replacement and 24% of fusion patients at two years had no improvement or deterioration of their preoperative pain.

Keep reasonable expectations.

Not everyone will be able to have complete pain relief. The challenge for the patient is to realize that complete relief of their pain may not be possible with disk replacement. Patient should decide whether to have the surgery based on the reasonable expectation of the risk of incomplete pain relief versus the potential of complete relief.

The challenge is to determine if disk replacement is appropriate for each person.

Surgeons have learned from the FDA trial and the European experience the patient selection is very important. Proper technique and placement of the artificial disk is very important also. The responsibility of the surgeon is to strictly adhere to the guidelines of the FDA study, and properly perform the procedure. This responsibility should maximize the benefit of the surgical result.

Will disk replacement become the gold standard for treatment of degenerative disk disease?

This is the big question for disk replacement. The same question was asked for hip and knee surgery in the 1970s. No one can predict the impact of TDR yet. In five years, we will be better able to answer this question.

Traditional treatment has been lumbar fusion.

Spine fusion surgery rather than artificial disk replacement has been the treatment of choice for individuals who have failed all conservative treatments including physical therapy and Cortisone injections for chronic low back pain. Spinal fusion surgery may not work perfectly. The average healing rate of lumbar fusion was 97% in our 10 year analysis of interbody cage fusions. The clinical success was 86.5% at two years and maintained at 87.8% at ten years. Spine fusion may take a longer time to heal completely (three to 24 months), and there is an increased rate of deterioration of adjacent motion segments over time. In our ten year study, 61% had radiographic changes of deterioration, and 20% with additional surgery recommended. This adjacent segment deterioration is a major concern for surgeon advising patients regarding spinal fusion.

Function of the normal disk.

The normal intervertebral disk has several functions. It is a spacer to maintain the height of the disk space and maintain the size of the foramina where the nerve root exits the canal. The disk is a shock absorber to allow the Spine to compress and rebound with activities such as jumping and running. It also withstands the pull of gravity during prolonged sitting or standing.

The jellylike center of the disk is called the nucleus pulposis. It has high water content. The outer ligamentous layer is called the annulus fibrosis. The annulus seals the disk space and resists pressure and prevents disk herniation. It is similar in function to a hydraulic shock absorber on an automobile.

The disk may be the source of pain as the nucleus dehydrates, and the disk space narrows and the annulus fails with cracks and bulging. Loss of the normal soft tissue tension may allow slipping of the spinal segments, bone spur formation, mechanical instability, narrowing of the foramina, and back pain. The disk may cause pain by disk herniation or disk degeneration without herniation.

Wear debris.

Debris is a concern with polyethylene implants of the hip and knee. It has been studied in the CHARITE artificial disk. Biomechanical testing simulating more than 10 years of use found no wear particles, so wear debris may not be clinically relevant in the TDR. Meticulous technique with implantation of the device placing the endplate prostheses parallel to one another will prevent abnormal wear and maximize the long-term result.

What are the results of the FDA Trial.

The study involved 375 patients at 15 centers across the country. The initial 71 patients were considered learning cases and not included in the final results. 205 patients received artificial disk replacement and 99 received BAK fusion cages. After two years of follow-up the clinical outcomes were very similar between the BAK fusion cages and the artificial disk replacement. In both groups pain and functional abilities improve substantially after surgery. The BAK fusion cage may not have been the best comparison because it is very difficult to assess fusion healing because of the interference in imaging of the titanium BAK cage.

What are the indications for Total Disk Replacement.

Disk replacement is not going to help everyone. Indications for potentially good candidate are:

1. Lumbar degenerative disk disease confirmed by medical history, x-rays, MRI and discogram.

2. Pain of degenerative disk disease not relieved by more than six months conservative treatment including physical therapy, injections, heat or cold, manipulation, etc.

3. The damaged disk is one of the two lower lumbar disks L4-5, L5-S1.

What are the contraindications for Total Disk Replacement.

Generally, the disk replacement is not recommended for anyone with back pain and one of the following conditions.

1. Multiple levels disk degeneration

2. instability of the spine (spondylolithesis, fracture, tumor)

3. poor bone quality, e.g. osteoporosis

4. previous major back surgery

5. patients with inflammatory arthritis of joints

6. patient with previous infection of the Spine

7. morbid obesity

Questions and Answers

How do I know if I have degenerative disk disease?

A. The diagnosis of degenerative disk disease is made on the patient’s medical history of chronic severe low back pain, and imaging including x-rays, MRI, and possibly lumbar discogram. X-rays will show narrowing of the disk space. The MRI will show decreased water content or hydration of the degenerative disk. A lumbar discogram will show leakage of dye and re-creation of the patient’s normal pain with the injection.

Will I need Spine surgery?

a. Rarely does degenerative disk disease require surgery. Conservative care including anti-inflammatory medication, physical therapy, exercise programs, manipulation, and hot and cold modalities, usually will restore lumbar spine health. Surgery is reserved for those with debilitating back pain that do not responded any conservative care for more than six months. Usually the painful disc and normal adjacent discs are identified by discography before surgery is recommended.

What type surgery is usually done for painful degenerative disks?

a. In general, surgical treatment is controversial because there may be other sources of pain than the degenerative disc. Lumbar spinal fusion is the standard surgery for mechanical low back pain, caused by painful degenerative disc disease. Fusion stops the motion of the painful degenerative disk. The un-fused adjacent disks must take on the motion loss by the fusion of the painful disk.

Is the artificial disk like a total joint replacement?

a. They are similar. Both have metal surfaces separated by a high density plastic piece. The artificial disk is inserted in a degenerative disk space. This restores disk height, improves spinal motion, and should decrease pain.

Is the artificial disk surgery complex?

a. The procedure is not that different or difficult for an experienced Spine surgeon. The surgical approaches from the left side of the abdomen and is the same approach is used for anterior lumbar fusion. Although the procedure is not difficult, the surgery is a major surgery and has associated risks of surgery.

What changes in the artificial disk you expect to see in the next few years?

a. The prosthesis itself will be further defined with a few new changes that should facilitate the function of the disk replacement. The surgical approach may also be improved with time and experience. The indications for the operation will become clearer. The careful selection of patients and meticulous surgical technique will remain the foundation of successful surgery.