Minimally Invasive Fusion Made Easier
You have a painful low back, and your doctor says that you need to see a spine surgeon. You have heard from your friends and family who have said, "Never let anybody operate on your spine" or "My friend had back surgery. He is now worse than he was before surgery," or the scariest, "It'll paralyze you."
At the Sonoran Spine, we''ve heard all the stories. We want to dispel the myths about spine surgery and help you to understand there are real solutions and outcomes so you can decide whether spine surgery might be a good option for your situation. In recent years, spine surgery has undergone big advances, some of which we've addressed in previous issues of our newsletter, Vertebral Views.
Anatomy and Functionality
Although we often take our spines for granted, the spine is one of the most important parts of the body. The spine keeps us upright, gives the body structure and support to move about freely and to bend with flexibility. It also protects the spinal cord, which is the connector of nerves to the brain and the rest of the body.
Our spine is comprised of 24 small bones called vertebra that stack upon each other to create a spinal column. A soft, gel-like cushion called a intervertebral disc lies between the vertebra to help absorb pressure and keep bones from rubbing together. Each vertebra is held together by ligaments. Ligaments connect bones to bones while tendons connect muscles to the bones.
As orthopaedic spine surgeons, we view your spine as the core of stability of your body. It allows you to move, twist, and turn in most every way – until you hurt and can't anymore. Most problems can be managed conservatively, but sometimes surgery is suggested when conservative treatment fails. Since various back problems are not treated the same, an accurate diagnosis is first made to understand the options for a particular diagnosis. The diagnosis allows us to know whether surgery can be considered if conservative management does, indeed, fail.
If Conservative Treatment Fails
If you have tried conservative management for a prolonged period and have now been told that your pain could benefit from stabilizing segments or joints through a technique called spinal fusion, fusion may be for you. Over the years, the indications for spinal fusion have expanded to benefit the spine with arthritis or a deformity, or both.
Spinal fusion surgery involves the use of bone graft so the vertebrae will grow, or fuse together. To assure proper rigid position while healing takes place, surgeons apply instrumentation, or implants such as screws and rods. The implants are connected together to maintain spinal stability and are rarely removed. Spinal fusion is used to restore spine stability and correct deformity.
Traditionally, spine surgeons have used an open approach to perform the spinal fusion. This includes an incision in the middle of the back and retracting muscles to the sides of the opening for easy access for the procedure. More recently, surgeons have sought ways to continue to help patients with a surgery that has stood the test of time, however, with less exposure and fewer complications. Minimally invasive spinal fusion surgery is one answer to this problem.
Times have definitely changed the options for spine fusion surgery. Typically, a patient will visit the surgeon and be diagnosed with arthritis of the spine or degenerative disc disease. If conservative options have proven to be ineffective, the surgeon may recommend the option of spine fusion surgery. Prior to 1980, you would have been hospitalized for about a month after surgery and be fitted for a back brace which had to be worn 24 hours a day for a year after surgery. Recovery was an arduous undertaking lasting about two years. The healing rate of the fusion (union of the bones) was successful in approximately 60-70% of patients. These patients experienced pain relief 80-90% of the time. Times have definitely changed.
With the advent of metallic instrumentation, surgical fusion rates using the traditional approach began to improve. Bracing is less likely needed. Recovery from the procedures is faster and less painful with less risk of complications. In some cases, it is still true that patients can expect to be off work for up to six months from the time of their surgery. Now there is another option – minimally invasive spinal fusion surgery.
Minimally Invasive Fusion Surgery
There are many techniques of minimally invasive spinal fusion. The technique I use is unique in that many patients can be discharged from the hospital the same day as their surgery. Only four incisions are made for placement of the screws and rods. Through the same small incisions, the bone work is performed to prepare the body to fuse the bones together.
The most common diagnoses for which this type of surgery can be utilized are degenerative disc disease, lumbar (facet) arthritis and Grade 1 spondylolisthesis (slipped vertebrae). The surgery is limited to a maximum of two levels (any lumbar level, for example, L4/L5 and L5/S1). The surgery is performed through the back; however, anterior (front) or interbody fusion can all be performed through the same incisions.
Performing the Surgery
Although to the patient it may seem complicated, minimally invasive surgery is a step-by-step procedure. Initially, fusion of the small joints (facet) is usually performed from the right hand side of the spine. The spinal instrumentation system uses four very small incisions which limits the amount of trauma to the surrounding tissue. This instrumentation used is passed through the skin. The next step is to remove the left facet joint. This bone removal allows the surgeon access to the disc between two vertebrae. The disc is removed, which removes the source of pain as well as it indirectly opens the area where the nerve passes through the spine. A spacer, a "cage", is placed between the two bones along with bone for the fusion. Spinal instrumentation is then placed on the right hand side of the spine. After the procedure, a numbing medication is injected in the incisional areas to help with postoperative pain control. The patient awakens from the surgery in the recovery room. A physical therapist evaluates the patient after surgery to ensure that he/she is safe to go home with a walker or other assistive walking device. When the patient is medically stable, the patient is discharged with prescriptions for pain and possible muscle spasms.
Patients are placed into a rigorous therapy program following surgery for 12 weeks. During the first week, walking is encouraged. Other exercises include stationary strengthening sets for lower extremity muscles. Aquatic therapy begins at the 2-4 week interval and continues throughout the program. Free weight training is introduced during the last month of therapy. We recommend continuing with aerobic conditioning and some form of resistive training for life to provide the best back health for years to come.
Most patients recover very quickly from minimally invasive fusion surgery compared to conventional spinal fusion surgery. Many patients can resume at least part-time work within 3-4 weeks from surgery. Some can return to full-time work within 6 weeks. Nearly all patients return to their previous level of activity by 12 weeks after surgery. At 12 weeks, there are no limitations on activity levels.
Patients who undergo a single level lumbar spinal fusion have an 80-90% chance of some pain relief once fusion is completely healed. About 90% of fusion surgeries heal as predicted. For patients who undergo a two-level fusion, the results are slightly less: 75-80% patients have improvements in their pain. Although most patients want to know how much pain will be relieved with surgical intervention, this is difficult to accurately predict; however, between 30-80% of their back pain will be relieved. Some patients even have complete relief of their pain, although this is not the norm.