Spinal Fusion and Spinal Infections
Spinal fusion is the surgical technique of combining two or more vertebrae. Fusion of the vertebrae involves insertion of secondary bone tissue obtained either through auto graft (tissues from the same patient) or allograft (tissues from the other person) to augment the bone healing process.
The human spine provides support to the body allowing you to stand upright, bend, and twist. The spine is made up of a series of 24 bones called vertebrae which are stacked on top of one another. Between two vertebrae there is a disc of cartilaginous tissue called intervertebral disc. Intervertebral discs act as shock absorbers and protect the spine from the strong forces of movement during activities such as jumping, running and lifting. The spine can be broadly divided into cervical, thoracic and lumbar spine.
Usually spinal fusion is recommended in patients with neurological problems or severe pain that have not responded to conservative treatment.
Indications for spinal fusion
Various spinal conditions may be treated though spinal fusion such as :
- Spinal stenosis
- Damaged disc
- Spinal tumor
- Fractures of the spine
- Scoliosis and Kyphosis (abnormal curvatures of the spine)
Spinal fusion can be performed through different angles depending upon the specific advantages of each and the choice of your surgeon. It may involve interbody fusion where bone graft is placed in the space present between the two vertebras. Other techniques may also be employed for spinal fusion that involves the entire removal of the disc between the affected vertebrae. A specially designed device made either from plastic or titanium may be placed between the vertebrae. This helps in maintaining spine alignment and normal height of the disc.
The fusion process is followed by fixation that involves fitting of metallic screws, rods, plates or cages to stabilize the vertebrae and accelerate bone fusion. After surgery, 6-12 months is the ideal time for complete fusion to take place.
The complications associated with spinal fusion include infection, nerve damage, blood clots or blood loss, bowel and bladder problems and problems associated with anesthesia. The primary risk of spinal fusion surgery is failure of fusion of vertebral bones which may require an additional surgery.
Talk to your surgeon if you have concerns regarding spinal fusion procedure.
The spinal cord and its surrounding structures can become infected by bacteria or fungal organisms. Risk factors that can make you more susceptible to these infections include older age, smoking, obesity, malnutrition, weakened immune system, infection with HIV virus, diabetes and cancer.
The most common types of spine infections are discitis, osteomyelitis, and an epidural abscess. Osteomyelitis refers to an infection of the vertebral bone of the spinal column and is caused by Staphylococcus Aureus, or other bacteria or fungus. Discitis is an infection of the disc between two vertebrae. Epidural abscess is a collection of pus between the dura, the membrane that covers the spinal cord and nerve root.
When you have infection in your spine you may feel ill and have a fever with chills, headache, stiff neck, back pain, redness and tenderness around the wound, and possibly drainage from the wound. You may also develop numbness and weakness in the extremities.
Spinal infection is diagnosed based on history, physical examination, and other imaging studies such as plain X-rays, CT scans or MRI scans. Blood cultures are obtained to detect the type of bacteria or fungus causing the infection. Additional blood tests may be ordered.
Treatment depends on the severity of the infection and the organism causing the infection.
Conservative treatment includes use of antibiotics or antifungal medications. A brace may be used to support the spine and to help relieve pain until the wound heals.
If the spinal infection causes instability of the spine, surgery may be required to remove the infection and decompress the nerves.
When there is an infection following spinal surgery, another surgery may be required to wash out the infection and remove infected tissue.
In some cases a combination of surgery and long term antibiotics may be used to treat spinal infections.