Risks of Back Surgery
Back surgery is usually undertaken once all conservative methods of treatment have been employed but pain and other symptoms persist. There are numerous risks to back surgery, including spinal fluid leaks, nerve damage, and infection, and patients need to be aware that surgery for pain relief carries a risk of actually increasing their pain and disability. Common surgeries for spinal stenosis, degenerative disc disease and arthritis may all be performed using endoscopic techniques which can complicate visibility during surgery and may result in the surgeon failing to spot a durotomy.
Long-Term Effects of Durotomy
The dura mater that covers the spinal cord is a protective, watertight sheath that can heal if accidentally torn during surgery, sometimes even if the tear is not immediately noticed and repaired. In most cases this incident has no lasting effects but where the dura fails to heal it may leak CSF into surrounding tissues and cause swelling as well as increasing the risk of spinal meningitis.
Lumbar Spine Surgery and CSF Leaks
According to Brookfield, et al (2008), dural tears are not uncommon complications of lumbar spine surgery and are usually repaired as and when they arise with subarachnoid drains fitted to clear any leaking fluid as the dura heals. Tissue grafting and the use of fibrin-adhesive sealant are also employed along with bed-rest to aid healing and reduce a build-up of fluid and the formation of a cavity in the spine. Long-term symptoms of spinal fluid leak after back surgery are usually prevented in cases where the tear is spotted and treated.
Delayed Symptoms of CSF Leak After Back Surgery
Where a dural tear (durotomy) is not recognized early and properly addressed, however, symptoms such as a headache and/or photophobia may arise. These symptoms of a cerebrospinal fluid (CSF) leak may be brought on by sitting upright after back surgery and it appears that most cases occur within seventy-two hours of incidental durotomy. Some patients do not develop symptoms until a week or more after surgery, however, especially where initial inflammation in the spine means that CSF leakage is slow at first. In such cases, patients may require additional back surgery to repair the dura and drain the fluid.
Treating Dural Tears
Treating spinal fluid leaks after back surgery will often involve compression to prevent further leakage while surgery is scheduled to repair the dural tear or while the tear heals itself. Compression bandages are often advised by a physician to minimize the risks of permanent cavities in the spine being created as the fluid leaks.
Persistent Symptoms of Spinal Fluid Leaks
Such cavities can continue to cause problems even after the spinal fluid leak has ceased. This is because they can instead fill with lymph, which itself puts pressure on the spinal cord and nerves and creates the same symptoms. Patients with large spinal cavities resulting from spinal fluid leak may have to have an accessible cover and drain placed into the wound to allow for fluid to be cleared frequently and for gauze and other packing material to be regularly changed in an attempt to get the body to fill in the cavity itself.
Using Glue for Spinal Fluid Leaks
A less invasive procedure for repairing dural tears and spinal fluid leak after back surgery involves percutaneous, CT-guided injections of fibrin glue to try to seal the wound. This is usually successful in repairing the spinal fluid leak but where it is unsuccessful it may be that an unsuspected secondary dural tear is responsible for continued symptoms. Patients may have further diagnostic imaging to ensure that all dural tears have been successfully plugged by the injected material. This can avoid the need for additional invasive procedures but where symptoms of spinal fluid leak after back surgery persist further surgery may become unavoidable.
Patel, M.R., Louie, W., Rachlin, J., (1996), Postoperative Cerebrospinal Fluid Leaks of the Lumbosacral Spine: Management with Percutaneous Fibrin Glue, AJNR: 17, March 1996.
Brookfield, K., Randolph, J., Eismont, F., Brown, M., (2008), Case Reports: Delayed Symptoms of Cerebrospinal Fluid Leak Following Lumbar Decompression, Orthopedics, August 2008 – Volume 31 · Issue 8: