Scar tissue, also referred to as fibrosis, occurs to some degree with all back surgery and is largely dependent on the invasiveness of the procedure. Patients’ general health and adherence to recovery guidelines also have considerable influence on the development of scar tissue after back surgery. Returning to physical activity too soon after spinal surgery can traumatize the spinal nerves and encourage inflammation and scar tissue formation. Conversely, inactivity may allow scar tissue to form over the nerve root and tether it in such a fashion that symptoms of a pinched nerve appear. Patients may be tested for the presence of a tethered nerve through a simple straight leg-raising test. If pain occurs upon lifting the leg then the test is considered indicative of the presence of nerve tethering and further back decompression surgery is likely to produce a good outcome in terms of pain relief. If there are signs that the nerve tethering is due to the presence of herniated disc material then the surgeon may wish to perform a discectomy to free the trapped nerve.
In cases where a patient develops pain after back surgery, the presence of scar tissue is often the only clear finding on an MRI scan, leading many clinicians to suggest that it is this fibrosis that is responsible for the pain many experience after spinal surgery. However, many patients have similar degrees of scar tissue without the progression of leg or back pain, making the conclusion controversial. The formation of a laminectomy-membrane is common after back surgery involving a laminectomy but not all patients suffer from leg or back pain associated with this scar tissue. The creation of scar tissue only occurs in the first few months after an operation, with most happening within six months of the back surgery. As such, if a patient develops recurrent pain months or years after their surgery it is unlikely to be attributed to the scar tissue formed after this procedure. The scar tissue may, however, contribute to further spinal stenosis and increase the possibility of disc bulging or osteophyte growth causing nerve impingement at an earlier stage.
Preventing Scar Tissue
It is extremely difficult to prevent the formation of any scar tissue after back surgery but techniques to reduce scar tissue do exist. Surgeons may be able to use fat grafts, gelatin sponges, and the implantation of silicon-based sheets to act as interpositional membranes preventing the growth of fibrous material around the nerves after back surgery. The degree of success is variable and many other factors need accounting for in the development of fibrosis. These membranes work by blocking the migration of cells into the area around the nerve root, but clinical significance from animal studies has failed to achieve a level sufficient for the techniques to become standard practice in human back surgery.
Patients are encouraged to fully engage with their physical therapy regime after back surgery, not only to condition the spinal muscles and maintain good condition for recovery, but also to limit the degree of scar tissue formation. Stretching the nerve root as healing occurs can prevent the nerve becoming stuck by scar tissue growth. The binding of a spinal nerve by adhesions can occur if the patient remains largely immobile in the first six to twelve weeks after back surgery, as this is when most scar tissue forms. Physical therapy exercises that move the spinal nerves may include ‘pumping’ the ankle up and down whilst stretching the hamstrings, but patients should not attempt such exercises without guidance from a physician who knows their full medical history as some movements may exacerbate their symptoms.
Treating Scar Tissue after Back Surgery
For patients with scar tissue after back surgery that is considered to be the cause of their back or leg pain, the options for treatment are, unfortunately, fairly limited. Further surgery to remove scar tissue is liable to actually create more scar tissue and worsen the problem. If scar tissue is extensive, and there is evidence that the nerve is bound by adhesions, further back surgery may be considered and patients should discuss this option with their surgeon. It may be that the patient experienced unexpected spinal trauma following the initial back surgery, such as a car accident or fall, that caused the formation of such extensive fibrosis.
In the majority of cases patients with adhesions compressing the nerve root the treatment options are quite limited. Medications, such as Neurontin, may be prescribed to try to limit back or leg pain, and patients will likely be given a strict regimen of physical therapy to attempt to release the trapped nerve. For some, this therapy will effectively free the nerve root from the adhesions and their pain will be alleviated. For others the therapy may be continued for three to twelve months and have little or no effect. Pain management is the only course then available and long-term analgesics are likely to be required to allow the patient to cope with their daily pain.