What is Spinal Fusion?
Spinal fusion is a surgical procedure done to permanently fuse two or more small bones of the spine (vertebrae) to make them into a single, solid bone so as to eliminate motion between them.
Spinal fusion is a surgical procedure done to permanently fuse two or more small bones of the spine (vertebrae) to make them into a single, solid bone so as to eliminate motion between them.
The vertebral column in humans consists of 33 vertebrae that are stacked one on top of the other and consist of 24 articulating vertebrae followed by the sacrum (which consists of 5 vertebrae fused into a single bone) and the coccyx (which consists of 4 fused vertebrae). The 24 articulating vertebrae are divided into 3 regions comprising of the cervical (7 in number), thoracic (12 in number) and lumbar (5 in number) vertebrae. The vertebrae are separated by intervertebral disks, which act as shock absorbers.
The spinal cord extends from the base of the skull to the lower back through a canal formed by an opening in each stacked vertebra. The spinal cord transmits information between the brain and the rest of the body through nerves that branch out through openings in the vertebrae.
When there is abnormal or excessive motion between the vertebrae, they compress the spinal nerves and cause pain. The reasoning behind spinal fusion is that the pain would stop if the bones do not move over each other.
Spinal fusion also prevents the stretching of nerves and surrounding ligaments and muscles. It is only recommended when the source of the pain has been detected accurately through imaging tests.
The surgery can be performed at all three levels of the spine; namely, the cervical, thoracic or lumbar regions. All techniques of spinal fusion involve bone grafting as the main part of the surgery. After some time, the bone graft and the vertebrae grow together and limit the motion at that segment, thereby relieving pain. The procedure is particularly useful in those with a significant loss of disc space height, deformity of the spine, and significant pain in addition to symptoms in the limbs.
Spinal fusion could partially restrict you from bending your back forward or backward. Although it does take away some spinal flexibility, most of the spinal fusions are performed only on small segments of the spine and do not limit motion much.
Spinal fusion is performed for various reasons and in various situations. Decisions to perform it are made taking into consideration the:
Spinal fusion is done along with other surgical procedures of the spine like decompression (foraminotomy or laminectomy) and after discectomy in the neck. The above procedures are done to remove bone and diseased tissues that narrow the openings through which the spinal nerves exit the vertebral column thereby putting pressure on the spinal nerves (spinal stenosis).
Spinal fusion is also done to relieve symptoms of many back conditions, including:
To perform a spinal fusion, the surgeon can approach the bone from different angles depending on the nature and location of the disease. For example posterior fusion is generally considered the gold standard for spondylolisthesis and the preferred approach for an anterior lumbar interbody fusion (ALIF) is by making an anterior incision in the abdomen.
The spine can be approached from the
The spinal fusion technique also varies depending on the level of the spine affected and the location of the compressed spinal cord/nerves. It can be done at the cervical (neck), thoracic (mid-back) and the lumbar (low-back) regions of the spine.
Your doctor will examine you and conduct several tests to confirm the diagnosis and the need for the surgery. A CT scan or an MRI are commonly conducted to diagnose back problems:
For a CT scan, you will be asked to lie down still on a special table for a few minutes. A doughnut-shaped instrument will pass over the part to be screened, and images will be taken. A contrast may be injected into your vein; therefore you should inform the radiologist if you suffer from any allergies.
For an MRI, you will be placed inside a narrow tube, which can sometimes make you claustrophobic, if you have a fear of enclosed spaces. Few centres do offer more open MRI machines, but the drawback is that the pictures may not be as clear. The MRI machine makes loud clicking noises and it is advisable to ask for earplugs to help block these noises out.
Routine tests:
All patients who undergo an elective surgery (which is more planned), routine tests are required and include the following:
In older group of patients, a detailed assessment of the heart maybe required.
A few preparations are required before a spinal fusion surgery; these are listed below:
Quit smoking: You will have to quit smoking well before the surgery since continuing to smoke before, during and after the procedure can affect the healing process. Smoking or inhaling tobacco smoke also irritates the breathing tubes and may reduce the function of your lungs during or after surgery.
Medicines: You will have to inform the doctor about the medicines you are taking, including herbs and supplements which you may take without a prescription. You will have to stop taking medicines that make it harder for your blood to clot two weeks prior to the surgery. These include drugs like aspirin and clopidogrel.
Keep underlying conditions under control: Any underlying conditions like diabetes, heart disease, or other medical problems, will have to be checked and kept under control by your regular doctor or the specialist you see for that condition.
Blood donation: Blood may be seldom required due to its loss sometime during the spine surgery; this can necessitate blood transfusion. Therefore, it is advisable to keep a stock of either the patient’s own blood or a matching blood type from friends, family or from a blood bank. The patient can donate his or her own blood (autologous donation) prior to the surgery in instalments, starting within four weeks and finishing at least seven days before the surgery. A technique called “cell-saver” is also present in some centers where the blood that is lost during the surgery is recycled and the red blood cells are given back to the patient.
Alcohol: Inform your doctor if you have been drinking a lot of alcohol.
Additional tests: The following tests might be required: Pulmonary or breathing function test to determine the lung’s capacity to expand, to see how much air you can breathe in and out. Scoliosis patients usually have difficulty breathing comfortably.
ECHO (echocardiogram) that takes a picture of your heart.
You will be advised medications to prevent constipation around a couple of days before the surgery, which will be continued during your hospitalization and for a few days after your discharge.
Apart from this, make sure you plan ahead for recovery at home post surgery.
Day before surgery: You will be instructed to avoid all food and liquid after midnight the night before the surgery. You will also be instructed about the medications you should take in the morning of the surgery with a sip of water. Check the recommended diet for the day before the surgery so as to limit the residue in the digestive tract.
On the day of the surgery
Type of Anesthesia – Spinal fusion is done under general anesthesia during which time you will be unaware of the operation. Your anesthesiologist will decide on the options of anesthesia and pain medication after the surgery after reviewing your health history and physical exam results.
When you are ready to be taken to the operating room, you will be transported there.
Shift to the Operating room - The ambiance in the operating room can sometimes be very daunting and a small amount of sedation can help overcome your anxiety. From the trolley, you will be shifted on to the operating table. As you look up, you will see the operating light console and at the head end will be the anesthesia machine. There may also be monitors to check oxygen levels, ECG and other vital parameters. A constant beeping sound may be present from the monitors, which may sometimes be irritating.
The Operating Room (OR):
The anesthesiologist will start the pain medication. Pain control can be achieved through a patient-controlled analgesia (PCA) (a computerized pump with a tube of pain medication delivered through the IV line) or an epidural catheter that delivers pain medication directly to the spine.
You may also be asked to breath through a mask, which is also used to help you fall asleep.
Once you are asleep, a few tubes will be inserted into your body for various purposes:
Procedure:
First, the doctor makes a surgical cut (incision) to view the spine. Spinal fusion is mostly performed after other surgeries such as diskectomy, laminectomy, or a foraminotomy.
Bone grafting: All spinal fusions require some type of bone material like a bone graft or artificial bone substitute to be packed between the vertebrae in order to bridge the gap and to help them heal together. The bone material can be
The bone graft stimulates bone healing by increasing bone production and makes the vertebrae heal into one solid bone.
The different ways of fusing the vertebrae together are:
Immobilization:Following bone grafting, the vertebrae need to be held together to help the fusion progress. It is common in today’s surgeries to supplement the bone graft with additional hardware like screws, plates, and rods. This is called internal fixation. They have higher union rates than non-instrumented fusions and are often used to hold the bones in place without moving while the graft fuses the two vertebrae together. Internal fixation helps to move about earlier after surgery.
Minimally invasive techniques are also gaining popularity. These allow rods and screws to be inserted into the spine with smaller incisions with the help of advanced image guidance systems. They have the advantages of less muscle damage, blood loss, infections, pain, and length of stay in the hospital.
Waking up from Anesthesia –Once fully awake, you will be shifted on the trolley and taken to the recovery room, where a nurse will monitor your vitals and observe you for an hour or two before shifting you to the room or a ward.
Post-operative recovery:
Recovery at home:
Potential complications are possible with any surgery. Please discuss them in detail with your surgeon prior to undergoing the procedure. Complications that may occur following spinal fusion surgery are as follows:
Spinal fusion is not likely to take away all your pain especially if you have had chronic back pain before the surgery. Since the area that was fused can no longer move, the areas above and below are more likely to be stressed when the spine moves. This could result in future spine problems.
Weight reduction and exercising with definitely help in recovery.
