What is Spinal Instrumentation?
Spinal instrumentation is used to straighten and stabilize the spine by surgically attaching metallic or non-metallic implants or devices to the spine after spinal fusion surgery. Instrumentation includes implants such as screws, plates, rods, hooks, cages, and interbody devices. Implanted instrumentation instantly stabilizes the spine post surgery, adding strength, and helps to maintain correct alignment while fusion occurs. Depending upon the type of fusion and instrumentation performed, the patient may need to wear a brace post surgery for added support while healing.
Anatomy of the Spine
The spine is made up of small bony segments called vertebrae. These vertebrae are categorized into cervical or neck vertebrae, thoracic (upper back), and lumbar (lower back). Cushioning discs present between each vertebra act as shock absorbers. A cylindrical bundle of nerve fibers called the spinal cord passes through the entire vertebral column and branches out to the various parts of our body. Any damage or deformity to the bones of the vertebral column or to the discs located between the vertebrae can damage these nerves, leading to pain in the body part that the nerve supplies.
Indications for Spinal Instrumentation
Spinal instrumentation refers to different types of implants and devices utilized during spine surgery. When spinal instrumentation is employed during spine surgery, the objective is to stabilize the spine in order to prevent movement while fusion occurs between two or more vertebrae. Bone graft is often utilized in instrumented surgical procedures to enhance fusion and stabilize the spine. Some types of graft assist to stimulate new bone growth which is crucial for a successful fusion.
Spinal fusion and instrumentation may be indicated to treat a spinal fracture or spondylolisthesis (slippage of one vertebra on another), correct spinal deformity, or stabilize the spine after discectomy. In addition, there are several other spinal disorders and conditions when fusion and instrumentation are required.
Common surgical procedures that necessitate spinal fusion and instrumentation include:
- Transforaminal Lumbar Interbody Fusion (TLIF)
- Posterior Lumbar Interbody Fusion (PLIF)
- Anterior Lumbar Interbody Fusion (ALIF)
- Anterior Discectomy and Fusion (ACDF)
Preparation for Spinal Instrumentation
Preoperative preparation for spinal instrumentation may involve the following steps:
- A review of your medical history and a physical examination are performed by your doctor to check for any medical issues that need to be addressed prior to surgery.
- Depending on your medical history, social history, and age, you may need to undergo tests such as blood work, urinalysis, and imaging to help detect any abnormalities that could compromise the safety of the procedure.
- You will be asked if you have allergies to medications, anesthesia, or latex.
- You should inform your doctor of any medications, vitamins, or supplements that you are taking or any conditions you have such as heart or lung disease.
- You may be asked to avoid medications such as blood thinners, aspirin, or anti-inflammatories for a specific period prior to surgery.
- You will be placed on a special diet prior to surgery and laxatives may be used to clean out your bowel.
- You may be instructed to shower with an antibacterial soap the night prior to surgery to help lower your risk of infection after surgery.
- You should refrain from alcohol or tobacco at least a few days prior to the surgery and several weeks after as it can hinder the healing process.
- You should not consume any solids or liquids at least 8 hours prior to surgery.
- You are advised to arrange for someone to drive you home after surgery.
- A signed informed consent form will be obtained from you after the pros and cons of the surgery have been explained.
Procedure for Spinal Instrumentation
Spinal instrumentation is most often performed after spinal fusion surgery and may involve the following steps:
- You will lie face down on the operating table under the influence of general anesthesia.
- A surgical cut is made over the affected vertebrae (cervical, thoracic or lumbar area).
- Muscles surrounding the affected vertebrae are retracted to gain accessibility to the vertebrae.
- The damaged vertebral bone or intervertebral disc is removed from the affected area of the spinal column.
- Your surgeon then performs spinal fusion. 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 a bone graft is placed in the space present between the two vertebrae. 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 the normal height of the disc.
- The fusion process is followed by spinal instrumentation, which involves fitting metallic screws, rods, plates, or cages to stabilize the vertebrae and accelerate bone fusion.
- Following this, care is taken to reposition the soft tissues carefully and the incision is closed.
Postoperative Care and Recovery
Postoperative care instructions and recovery after spinal instrumentation may involve the following steps:
- You will be transferred to the recovery area where your nurse will closely observe you for any allergic/anesthetic reactions and monitor your vital signs as you recover.
- You may experience pain, inflammation, and discomfort in the operated area. Pain and anti-inflammatory medications are provided as needed for comfort.
- Application of cold and warm compresses to the treatment area is also recommended to reduce inflammation and pain.
- Antibiotics are also prescribed as needed to address the risk of surgery-related infection.
- You are encouraged to walk and move around in bed with support as frequently as possible to prevent the risk of blood clots.
- Instructions on surgical site care and bathing will be provided to keep the wound clean and dry.
- Avoid lifting, bending, or twisting your back for the first 6 weeks. Do not lift anything heavier than 5 pounds for the first 2 weeks. Refrain from any strenuous activities such as housework, yard work, or sex for at least a month.
- A corset or brace is recommended to limit bending and assist with the healing of the fused region.
- A physical therapy protocol is recommended to help strengthen the spinal area and optimize its function. Walking is a good exercise and is strongly recommended to improve your endurance.
- Refrain from driving until you are fully fit and receive your doctor’s consent.
- You should be able to resume your normal activities in a couple of weeks but may have certain activity restrictions.
- Complete recovery and return to work vary from patient to patient as it is related to a patient’s overall health status and the type of work one does.
- A periodic follow-up appointment will be scheduled to monitor your progress.
Risks and Complications
Spinal instrumentation surgery is a relatively safe procedure; however, as with any surgery, some risks and complications may occur, such as:
- Blood clots
- Allergic/anesthetic reactions
- Hardware failure
- Bone graft migration
- Persistent pain
- Failure of vertebral fusion
- Injury to adjacent organs, nerves, or blood vessels