What is Spinal Fusion Surgery?
The joining of one or more vertebrae with no gaps between them is called fusion. The concept of fusion is similar to the welding phenomenon in the industry. However, vertebrae are not fused together during spinal fusion surgery.
Bone grafts taken from the patient or obtained from cadavers are placed around the spine. The body heals these grafts in the next few months like fracture healing and fuses the vertebrae together.
When Is Fusion Needed?
Fusion is used in the treatment of a broken vertebra, correction of a spinal deformity (spinal curvatures, scoliosis, or shifts), and relief of pain from painful movement; It can be applied in the treatment of instability and in the treatment of some cervical disc slips.
One of the less controversial causes of spinal fusion is vertebral fractures. While not all spinal fractures require surgery, some fractures, particularly those involving spinal cord or nerve injury, need fusion.
Some spinal deformities (eg scoliosis) are treated with spinal fusion. Scoliosis is an “S” shaped curvature of the spine that can be seen in children and adolescents. Fusion may be necessary for very large curves or smaller curves that tend to progress.
Sometimes a thin fracture line can cause the vertebrae to slide forward over each other. This is called spondylolisthesis and can be treated with fusion surgery. Cervical disc hernias that require surgery usually require fusion with the removal of the herniated disc.
In this procedure, the disc is usually removed through an incision made in the front of the neck, and a small piece of bone or titanium cage is placed in the place of the disc. Although disc removal is usually performed with fusion in the neck, this is not true for the lumbar region.
Sometimes spinal fusion may be considered for the treatment of a painful spinal condition without obvious instability. The biggest obstacle to the successful treatment of spinal pain with fusion is the difficulty in identifying the source of the patient’s pain.
In theory, the source of pain is painful movement, and removing the movement by fusing the vertebrae together will also eliminate the pain. Unfortunately, it is not always possible to understand exactly which of the many complex structures in a patient’s back or neck is the source of pain with the techniques we have.
Because the source of the pain is so difficult to find, the treatment of low back and neck pain only with spinal fusion is controversial. Under these circumstances, fusion is often seen as a last resort and should only be considered after other conservatives (non-surgical) measures have failed.
In addition, in recent years, removable disc prostheses, which protect the movement instead of fusion and replace the diseased disc, can be considered as a treatment alternative.
How Is Spinal Fusion Surgery Made?
There are many surgical approaches and methods to fuse the spine, all of which involve placing a bone graft between the vertebrae. The approach to the spine and graft placement is done either posteriorly (posterior approach), anteriorly (anterior approach), or a combination of both.
While the anterior approach is used more frequently in the neck; lumbar and thoracic fusion is usually done posteriorly.
The main purpose of fusion is to create a fixed union between two or more vertebrae. Additional hardware (instrumentation) such as rods, screws, and cages may or may not be used in fusion, as the case may be.
Instrumentation is sometimes used to correct a deformity but is often used as a kind of internal support to hold the vertebrae together while the bone grafts heal.
Whether or not instrumentation is used, it is important to use bone or bone-like materials to fuse the vertebrae. The bone to be used in the surgery can be taken from another bone of the patient (autograft) or bone prepared from a cadaver (allograft).
Fusion with bone from the patient has a long history and results in predictable healing. Autograft is currently the gold standard bone source for fusion. Allograft (cadaver bone) can be used as an alternative to the patient’s own bone.
Although healing and fusion with respect to the patient’s own bone are not equally predictable, bone removal through another incision for the allograft does not require bone removal and therefore causes less pain.
Smoking, medications you use for other diseases, and your general health can also affect the speed of healing and fusion.
Promising research is currently underway on synthetic bone as a substitute for autograft or allograft. In due course, it is possible that synthetic bone products, bone-forming proteins, and growth factors (BMP) may replace the routine use of autograft or allograft bone.
With new “minimally invasive” surgical techniques, fusion can sometimes be done through smaller surgical incisions. Required indications for minimally invasive surgery traditional large incision
ion is the same as surgery, but this does not mean that a smaller incision surgery is less risky.
What is the Post-Surgery Process in Fusion Surgery?
The pain and discomfort that will occur immediately following spinal fusion is usually greater than with other spinal surgeries. But there are excellent methods of controlling postoperative pain. These include oral pain medications and intravenous injections.
Another option is the patient-controlled postoperative pain control pump (PCA). In this technique, the patient presses a button that releases a predetermined amount of narcotic pain reliever into the vein. This instrument is frequently used for the first few days after surgery.
The recovery period following fusion surgery is longer than other spinal surgeries. Patients usually stay in the hospital for five or seven days after surgery, but a longer hospital stay is not uncommon after a larger surgical operation.
Likewise, returning to a normal, active lifestyle takes more time after fusion than with other spinal surgeries. This is so because you need to wait until your surgeon sees evidence of bone healing.
The development of fusion progresses differently in each patient; As the body heals, it incorporates the bone graft to fuse the vertebrae firmly. The healing process after fusion surgery is very similar to fracture healing. Usually, the earliest sign of bone healing does not appear on an X-ray before six weeks.
During this period, the patient’s activities are usually restricted. Tangible bone healing usually does not occur six months after surgery. Although evidence of continued bone healing is seen for one year after surgery, an increase in activities is allowed after three to four months.
The time required for the patient to work depends on both the type of surgery and the job. The time you need to get a report may vary between 4-6 weeks after a single-level fusion in a young, healthy patient working at a desk job, and 4-6 months in an older patient working in a more physically demanding job.
Although the use of a brace after fusion therapy limits activities, a brace can be used in the early postoperative period. There are many types of corsets; some are very restrictive and limit a significant amount of movement, while others are more designed to relax and provide some support.
Whether or not a brace will be used, and if so, which type of brace will be used depends on your surgeon’s preference and other factors related to the type of surgery.
Rehabilitation Process After Fusion Therapy
After spinal fusion surgery, your surgeon may recommend you a postoperative rehabilitation program. In this rehabilitation program, there may be back-strengthening exercises, an aerobic program that strengthens the cardiovascular system, and a program specially designed for the work environment to return the patient to work as soon as possible in the safest way possible.
The decision to continue with a postoperative rehabilitation program is based on many factors. These are surgery-related factors (type and extent of surgery) and patient-related factors (age, health status, expected degree of activity). Rehabilitation can be initiated as early as 4 weeks in a young patient with a single-level fusion.
Are There Any Side Effects of Spinal Fusion Surgery?
While fusion is a cure for some spinal diseases, it will not return your spine to “normal”. In the normal spine, there is some movement between the vertebrae. Fusion destroys the ability to move between the fused vertebrae. This may put more strain on the vertebrae above and below the fusion. Fortunately, a fusion very rarely breaks after it has healed well.
However, fusion puts more strain on the adjacent vertebrae. Therefore, it has the potential to accelerate the degeneration of these segments. Of course, this risk varies between individuals. For this reason, to minimize the burden around the fusion, most surgeons recommend spinal fusion patients avoid repetitive heavy lifting and rotational movements.
The decision to apply spinal fusion or not is very complex, it is closely related to the factors related to the disease being treated, the patient’s age and health status, and the patient’s expectation of postoperative activity. Therefore, you should be very careful when making a decision and discuss everything in detail with your surgeon.