Decompression & Fixation
Introduction
The lower back, or lumbar region, is made up of the five lowest vertebrae (L1 – L5) that are just above the base of the spine. The lumbar region supports the bulk of the weight of the upper body and is the most common area of back pain.
Decompression is a surgical procedure that is performed to alleviate pain caused by pinched nerves (neural impingement). Compression of the nerve roots and narrowing of the lumbar spinal canal can be caused by the intervertebral disc, ligaments and overgrowth of bone (osteophytes). Compression of the nerve roots can lead to pain in the legs (calves) on walking, numbness and weakness in the legs on walking and occasionally bowel and bladder complaints.
Candidate for decompression if you have :
- Significant pain, weakness, or numbness in your leg or foot
- Leg pain worse than back pain
- Not improved with physical therapy or medication
- Difficulty walking or standing that affects your quality of life
- Diagnostic tests (MRI, CT, myelogram) that show stenosis in the central canal or lateral recess.
- Spinal stenosis, a herniated disc
- Isthmic or degenerative spondylolisthesis
- A spinal tumor
Spinal decompression can be performed anywhere along the spine from the neck (cervical) to the lower back (lumbar). The procedure is performed through a surgical incision in the back (posterior).The lamina is the bone that forms the backside of the spinal canal and makes a roof over the spinal cord. Removing the lamina and other soft tissues gives more room for the nerves and allows for removal of bone spurs. Depending on the extent of stenosis, one vertebra (single-level) or more (multi-level) may be involved.
There are several types of decompression surgery:
Laminectomy is the removal of the entire bony lamina, a portion of the enlarged facet joints, and the thickened ligaments overlying the spinal cord and nerves. Laminotomy is the removal of a small portion of the lamina and ligaments, usually on one side. Foraminotomy is the removal of bone around the neural foramen – the space between vertebrae where the nerve root exits the spinal canal. This method is used when disc degeneration has caused the height of the foramen to collapse, resulting in a pincheced nerve. It can be performed with a laminectomy or laminotomy. Laminoplasty is the expansion of the spinal canal by cutting the laminae on one side and swinging them open like a door. It is used only in the cervical area.
Spinal fusion may be done at the same time to help stabilize sections of the spine treated with laminectomy or laminectomies at multiple vertebrae levels. Fusion is the joining of two vertebrae with a bone graft held together with hardware such as plates, rods, hooks, pedicle screws, or cages. The goal of the bone graft is to join the vertebrae above and below to form one solid piece of bone. There are several ways to create a fusion.
Advantage of – Fusing the joint
- Prevents the spinal stenosis from recurring and can help eliminate pain from an unstable spine
- Prevent movement between the involved vertebrae and realign the spinal column so as to reduce the pain. The screws are rods are made of either titanium or stainless steel and are well tolerated by the body.