Spondylolysis relates to instability of specific bones
in the low back. It a very common cause of back pain, particularly in
adolescents. Gymnasts who perform routines that bend and arch the back
are often victims of spondylolysis or spondylolisthesis.
Spondylolisthesis and spondylolysis are caused by joint instability in
the low back. The rear part of spinal vertebrae has facet joints that
act as hinges, allowing our spines to twist and bend. Sometimes, however,
the posterior element can crack. Either from heredity or wear and tear,
part of the posterior element called the pars interarticularis can crack,
causing the vertebrae slip forward out of its correct position. Spondylolysis
occurs when the PARS hinge is cracked, but the vertebrae is still in its
correct position. Spondylolisthesis occurs when the cracked PARS has allowed
the vertebrae to slide forward out of its correct position. If left untreated,
spondylolysis can lead to spondylolisthesis.
Interestingly, in many cases, spondylolisthesis may have no symptoms,
so most people may not know they have it. Back pain is the most common
symptom, particularly in the lower back. This back pain may be mistaken
for a muscle strain. Muscle spasms that occur as a result of spondylolysis
may cause an overall feeling of stiffness in the back and may effect posture.
Outlined below are some of the diagnostic tools that your physician may
use to gain insight into your condition and determine the best treatment
plan for your condition.
Medical history: Conducting a detailed medical history
helps the doctor better understand the possible causes of your back
and neck pain which can help outline the most appropriate treatment.
Physical exam: During the physical exam, your physician
will try to pinpoint the source of pain. Simple tests for flexibility
and muscle strength may also be conducted.
X-rays are usually the first step in diagnostic testing
methods. X-rays show bones and the space between bones. They are of
limited value, however, since they do not show muscles and ligaments.
MRI (magnetic resonance imaging) uses a magnetic field
and radio waves to generate highly detailed pictures of the inside of
your body. Since X-rays only show bones, MRIs are needed to visualize
soft tissues like discs in the spine. This type of imaging is very safe
and usually pain-free.
CT scan/myelogram: A CT scan is similar to an MRI in
that it provides diagnostic information about the internal structures
of the spine. A myelogram is used to diagnose a bulging disc, tumor,
or changes in the bones surrounding the spinal cord or nerves. A local
anesthetic is injected into the low back to numb the area. A lumbar
puncture (spinal tap) is then performed. A dye is injected into the
spinal canal to reveal where problems lie.
Electrodiagnostics: Electrical testing of the nerves
and spinal cord may be performed as part of a diagnostic workup. These
tests, called electromyography (EMG) or somato sensory evoked potentials
(SSEP), assist your doctor in understanding how your nerves or spinal
cord are affected by your condition.
Bone scan: Bone imaging is used to detect infection,
malignancy, fractures and arthritis in any part of the skeleton. Bone
scans are also used for finding lesions for biopsy or excision.
Discography is used to determine the internal structure
of a disc. It is performed by using a local anesthetic and injecting
a dye into the disc under X-ray guidance. An X-ray and CT scan are performed
to view the disc composition to determine if its structure is normal
or abnormal. In addition to the disc appearance, your doctor will note
any pain associated with this injection. The benefit of a discogram
is that it enables the physician to confirm the disc level that is causing
your pain. This ensures that surgery will be more successful and reduces
the risk of operating on the wrong disc.
Injections: Pain-relieving injections can relieve back
pain and give the physician important information about your problem,
as well as provide a bridge therapy.
Conservative treatments should always be considered first when treating
spondylolysis. Nonsurgical treatment methods include resting and refraining
from usual activities, taking anti-inflammatory medication, and incorporating
a stretching and strengthening program. While ligaments and muscles can
help hold the vertebrae in place, over time, surgery may be necessary
to install surgical instrumentation or bone grafts that lock the vertebra
in place so that it does not slide out of position and damage the spinal
nerves. Surgery may involve a fusion and/or screws and rods.
Can spondylolisthesis be prevented?
Good spinal care, both in developing good musculature and in preventing overuse or injuries, is key into reducing the chance of developing spondylolisthesis. Athletes, especially, need to be knowledgeable about body mechanics and the importance of both strengthening and resting the muscles of the back.
What treatment options are there for spondylolisthesis?
1. Anterior or Posterior Decompression with fusion cages
The goals of surgery are to remove pressure on spinal nerves (decompression), and to provide stability to the lumbar spine. Decompression involves removing the damaged structures that are causing the spondylolisthesis. In most cases of spondylolisthesis, lumbar decompression is accompanied by the uniting of one spinal vertebra to the next (spinal fusion) with spinal instrumentation (implants that are used to assist the healing process). Surgery can be performed from the back of the spine (posterior) or from the front of the spine (anterior). A structural graft is inserted into the place previously occupied by the removed structure. The purpose of this graft is to hold the disc space open until the fusion is complete. The graft is often held in place by a "cage" device, such as the BAK cage.
2. Laminectomy decompression with graft
In the laminectomy procedure, the spine is approached through a two-inch to five-inch incision in the midline of the back, and the left and right back muscles are detached from the lamina on both sides. The lamina are flat bone projections on each side of the vertebra. After this is accomplished, the lamina is removed (laminectomy), allowing the doctor to see the nerve roots. The facet joints, which are directly over the nerve roots, may then be trimmed to give the nerve roots more room. Once the nerve roots have adequate space made by the removed lamina and facet joint trimmings, pressure is eliminated, thereby alleviating pain. Bone graft chips may be placed between the vertebrae to create a solid section of bone, preventing motion that may detract from healing.
3. Posterolateral fusion
The posterolateral fusion involves placing bone graft in the posterolateral portion of the spine (behind and to one side of the spine).The surgical approach to the spine is from the back through a midline incision that is approximately three inches to six inches long. First, bone graft is obtained from the pelvis (the iliac crest). Most surgeons work through the same incision to obtain the bone graft and perform the spinal fusion.
Next, the harvested bone graft applied to the posterolateral portion of the spine. This region lies on the outside of the spine and is rich in blood to supply the nutrients for it to grow. A small extension of the vertebral body in this area (transverse process) is a bone that serves as a muscle attachment site. The large back muscles that attach to the transverse processes are elevated to create a bed to lay the bone graft on. The back muscles are then laid back over the bone graft, creating tension to hold the bone graft in place.
After surgery, the body uses a natural process to repair itself, which usually means growing bone. As the harvested bone graft grows and adheres to the transverse processes, the spinal fusion is achieved and motion at that segment is stopped. Spine surgery instrumentation (medical devices) is sometimes used as an adjunct to obtain a solid fusion.
4. Spinal instrumentation with pedicle screws
For spine operations to be successful, solid healing of bone across the spine must be achieved. Dr. Regan's private practice makes use of metal devices, also called instrumentation (screws, rods, plates, cables, wires) that can help correct a deformed spine and will also increase the probability of obtaining a solid spinal fusion.
Spinal instrumentation can be placed in the front or in the back portion of the spine. The devices are usually made of metal, commonly stainless steel or titanium. In order to place this instrumentation into the spine, the spine is at first exposed by making a skin incision, and then gently clearing the muscles, ligaments and other soft tissues from the levels of the vertebrae to be fused. Specific tools are used to carefully prepare the bone in such a way to obtain good seating of the implants (screw, rod, wire, cable or other). When these devices are in the proper position, a rod (or plate) is positioned to link the implants together. Screws are inserted into the pedicles, which are part of the arch of the vertebra. This essentially forms a rigid scaffolding to hold the spine in the desired position. The bone graft which has been placed into the area of fusion gradually solidifies over several months. The spinal instrumentation is gradually covered by scar tissue and sometimes bone which the body lays down.
How do I know if I am at risk for spondylolysis?
Those with a family history of spondylolysis or weak vertebrae are more
susceptible to developing the condition. Also, athletes involved in activities
that place a great deal of stress on the back, such as football players
and weight lifters, are at greater risk for fracturing the vertebrae,
Click here for narrated videos of spine surgeries, procedures and what causes various symptoms. Click here to see medical illustrations that help you understand back and neck problems. Click here to see an exercise library that has special stretches that can relieve pain symptoms.
Our spine Internet site acts as on-line spine encyclopedia. In addition, as a free community service, Spine Group Beverly Hills mails out Home Remedy Books on a limited basis to residents in Southern California. Click here to learn more.
We understand that traveling with a back problem can be difficult and unsettling. That’s why we enable you to set up a telephone consultation with Spine Group Beverly HIlls in advance, to determine if a trip would be worthwhile. Because this involves significant time for our practice to receive your information and diagnostics, and for Dr. Regan to review your case in advance of your call, there is a fee for this consultation. Click here to learn more.
The vast majority of back problems improve on their own or with nonsurgical treatment. There are a few warning signs, however, that may indicate serious spinal problems. If you experience any of these symptoms, seek medical attention immediately. Click here to learn more.