Your decision to undergo surgery to relieve your back pain was most likely a difficult one. So it can be especially upsetting if, after your surgery, you are still not experiencing relief.

Despite careful diagnosis and a successful operation, some patients may still experience pain after their back surgery. This persistent pain or continuation of symptoms is known as failed back syndrome (sometimes called failed back surgery syndrome), and it can affect your ability to complete daily tasks. The failure is not of the surgery itself, as the goals of the surgery, which may include decompression and stabilization, may have been achieved. The failure is to achieve complete resolution of symptoms.

Several factors affect the outcome of spine surgery. One possibility is that the lesion that was operated on was not the only cause of the pain. Sometimes the main problem has not been adequately fixed. In rare cases there may also be damage from the surgical procedure itself that is causing pain.

When back surgery does not help to relieve your pain or leads to new pain, it’s easy to feel discouraged. The good news is that there may be another treatment option: chronic pain therapies.

The formation of scar tissue after back surgery is part of the normal healing process. Scar tissue pain is highly unusual because scar tissue itself has no nerve endings to cause pain.

However, epidural fibrosis, the formation of scar tissue near the nerve root, can put pressure on the nerve roots and thereby cause pain. Typically, symptoms associated with epidural fibrosis appear about 6 to 12 weeks after back surgery. Sometimes patients experience good pain relief early on after their surgery, but as the scar tissue slowly forms, the pain relief diminishes and leg and back pain recurs or increases. Occasionally the nerve damage from the original cause of the patient's pain makes the nerve heal more slowly. Burning pain, or a constant gnawing pain that does not change with position, can be suggestive of scarring around nerves.

Postoperative stretching exercises can help decrease the effects of postoperative scarring around the nerve root.

In a decompression surgery, such as a laminectomy or discectomy, the nerve root can take a long time to heal, making it difficult to gauge the outcome of the surgery right away.

Around three months after surgery, one of two outcomes may start to become apparent:

  • In general, patients who are getting better within three months of the surgery will continue to improve.
  • Patients who have not noticed any improvement approximately three months after the decompression are unlikely to receive substantial benefit from the surgery.

Decompression of the spine will usually relieve the patient’s leg pain immediately after the back surgery. However, for 10% to 20% of patients, the pain will continue until the nerve starts to heal.

It usually takes far longer for symptoms of numbness/tingling or weakness to resolve, and sometimes it can take up to a year for these symptoms to subside. If these symptoms persist after a year, it is most likely permanent nerve damage and is unlikely to get better.

Recurrent Stenosis After Decompression

Years after a laminectomy, spinal stenosis can come back (the bone can grow back and narrow the spinal canal) at the same level, or a new level, causing back or leg pain.

Technical Problems After Decompression Surgery

Three potential technical problems could cause the pain to continue after surgery:

  • A missed fragment of the disc or bone is still pinching the nerve.
  • The back surgery operation was done at the wrong level of the spine.
  • Dissection of the nerve root may have caused further trauma.

At times, decompressing a nerve root through back surgery will cause it to become more inflamed and lead to more pain temporarily until the inflammation subsides.

Inadequate Decompression of a Nerve Root After Surgery

Decompressing a nerve root with back surgery is not always successful, and if a portion of the nerve root is still pinched after the back surgery, there can be continued pain. If this is the case, there will usually be no initial pain relief following the back surgery, and the spinal stenosis may still be seen in imaging in a portion of the spine.

If you’re experiencing pain after decompression surgery, there may be another option that can help relieve your pain. 

A fusion is like a broken bone trying to heal. Bone cells migrate from roughened bone over the bone graft to other roughened areas and form solid bone. It takes about a year for solid bone to form. Activities such as excessive motion, poor placement of screws or rods, or the use of anti-inflammatories can inhibit this process of bony fusion. If bony fusion does not occur, eventual failure of the implants can occur, sometimes leading to breaks, pullouts, and chronic pain.

A patient may experience recurrent pain many years after a spine fusion surgery. This can happen because the level above or below a segment that has been successfully fused can break down and become a new source of pain. This is called adjacent-segment disease.

If you’re experiencing chronic pain after a spinal fusion, there may be another option that can help relieve your pain.

Arachnoiditis is the inflammation of the arachnoid, one of the delicate, web-like membranes that surrounds and protects the nerves of the spinal cord.

Causes and Symptoms

Inflammation can lead to the formation of scar tissue and can cause the spinal nerves to stick together and malfunction. The arachnoid can become inflamed because of an irritation from infection (such as meningitis), or from trauma (such as a fall), surgery, lumbar puncture, or myelography (a test to diagnose disorders of the spinal canal and cord). If the inflammation becomes chronic, it means that the nerve roots are damaged.

Typically, arachnoiditis affects the nerves connecting to the lower back and legs, causing chronic debilitating pain. Symptoms include weakness, numbness, tingling, stinging, and burning in the legs. Symptoms can be very severe. Some people are unable to work and suffer significant disability because they are in constant pain.

Diagnosis and Treatment

Diagnosing arachnoiditis can be challenging, but tests such as the CAT scan (computerized axial tomography) or MRI (magnetic resonance imaging) can help with diagnosis. A test called an electromyogram (EMG) can assess the severity of the ongoing damage to affected nerve roots by using electrical impulses to check nerve function.

There is no cure for arachnoiditis. Non-surgical treatments that focus on managing the pain are generally recommended. Often, health care professionals recommend a program of pain management, physiotherapy, exercise, and psychotherapy.

Spine surgery is generally not recommended because outcomes can be poor and provide only short-term relief. Additionally, scar tissue may continue to develop, and the spinal canal may be exposed to further trauma.

Chronic pain therapies may be an option if you’re experiencing arachnoiditis as the result of spine surgery. Learn about chronic pain therapies.