The lower back or lumbar spine is made up of five bones, called vertebrae. In between each vertebra is a softer structure, known as a disc. The discs are spongy and
act as shock absorbers as we move, bend, and twist.
Behind the vertebrae and discs is the spinal canal, which houses the spinal dura and cauda equina*. At each level of the lumbar spine, nerves exit the spinal dura and carry signals to and from the buttocks, legs, and feet.
The laminar arch or the lamina is the “roof” of the spinal canal. The lamina forms a bridge which connects to the vertebral bodies. Together these bony structures surround
and protect the dura and nerve roots. The laminae are connected to one another by articulating joints, which are known as facet joints.
* The dura is a thick membrane which surrounds the cauda equina. The cauda equina, or “horse’s tail” in latin, is a bundle of spinal nerves in the lumbar spine which provide motor innervation to the muscles, joints, and organs of the lower body.
As we age, our bodies experience wear and tear. The spinal discs lose water content and may begin to lose their ability to act as a shock absorber between the lumbar vertebrae. This naturally occurring cascade is known as Degenerative
Disc Disease or DDD.
DDD is often considered a combination of events which are part of the normal aging process. These may include bulging or herniation of the discs, loss of disc height, development of bone spurs around the spinal laminae and vertebrae, and/or thickening of the ligaments which surround the spinal canal and dura. In some cases, pressure from these structures can be placed upon the spinal dura and/or nerves by the bone spurs or disc material, which in turn may lead to back pain, or other symptoms such as radiating pain, numbness, weakness or tingling in the buttocks, legs, or even extending into the feet.
In the vast majority of cases, non-surgical treatments are effective in reducing or eliminating the symptoms of DDD. These
may include rest, heat, massage, or physical therapy. Your physician may prescribe any or a combination of these treatments or others to address your symptoms. Medications such as anti-inflammatories may be helpful, and in some more persistent cases, injections may be used to reduce inflammation or block the signals causing your symptoms.
If your symptoms have not been responsive to the above therapies, or if they worsen, your doctor may recommend spine surgery. As with non-surgical treatments, there are many alternative surgical options available. These include but are not limited to:
Depending upon the root cause of your symptoms, the spinal surgeon will decompress or widen the areas in your spine which are pressing upon the neural structures.
This may include laminotomy or the removal of a portion of the laminar arch which covers the spinal canal.
Once the spinal canal is visible, the surgeon can remove the bone, ligament, and/or disc material which is compressing the dura and nerve roots. Providing additional space for these structures is the main goal of the decompression. Removal of a herniated disc or bulging disc may be referred to as “Discectomy”.
If the spinal segment is unstable or if your surgeon is
concerned that it may become unstable due to the decompression, a spinal fusion may be recommended.
In the healthy spine, the spongy disc between the vertebrae allows for movement to occur. When this movement is excessive due to instability, pain may result. Spinal fusion is the process of eliminating motion between two vertebrae by welding them together, or “fusing” them.
Once bone has grown across the space between two vertebrae, motion would no longer occur. There are different methods which can be used by your surgeon to facilitate this process, and it is important to discuss these alternatives with him/her.
One relatively common procedure which is used to facilitate a spinal fusion is the implantation of pedicle² screws and rods. The screws are anchored to the spine and connected
to one another by a rod to keep the segment from moving. Pedicle screws and rods act as an internal brace to hold everything in place while the fusion occurs.
² The pedicle is a tube of bone that connects the lamina to the vertebral body to form the vertebral arch.
As surgeons look for less invasive techniques to perform spine surgery, several new implant options have been introduced. Some of these involve pedicle screw and rod systems which require less disruption to the tissues surrounding the implant system than their conventional
counterparts. Other options may employ different ways to internally brace the spinal segment during the healing process.
At LinkSPINE our mission is to provide a whole kit of different innovative spinal fusion devices that require fewer screws, use smaller exposure yet guarantee extraordinary strength than conventional systems.
Why Does My Back Hurt?
The spine is a complex set of structures and there may bemultiple underlying causes for back pain, leg pain, or other symptoms. These include but are not limited to:
•The back muscles are working “overtime” to compensate for spinal alignment problems
•The spinal segment is unstable
•Arthritis of the facet joints
How Does a Problem in My Spine Cause Pain in My Buttocks or Legs?
A pinched nerve can be caused by pressure from a bone spur, or by a herniated or bulging disc. Because spinal nerves carry signals to the lower extremities, a pinched nerve can be painful all along its path.
How Are My Symptoms Diagnosed?
Your history, physical examination and images such as plain films, MRI, and CT scans provide valuable information to your
physician regarding the root cause of your symptoms.
Why Is a Spinal Fusion Being Recommended?
Spinal fusion is a stabilization technique designed to address symptoms associated with spinal instability.