1. Epidural Fibrosis Scar tissue after back surgery is a necessary part of the healing process and in most cases, causes no pain since there are no nerves in scar tissue. However, the build-up of scar tissue can press on other structures that do have nerves. Scar tissue can also attach one structure to another in an abnormal configuration or put the tissue under tension which can cause pain.
Epidural fibrosis (another fancy word for scar tissue) is the formation of scar tissue near the nerve root that puts pressure on the nerve roots. Symptoms of epidural fibrosis appear about 6 to 12 weeks after their procedure. Any damage to a nerve can train the nerve to fire off signals even when the original problem is fixed. This is referred to as phantom pain and is seen commonly in people with amputated limbs. Burning pain is a gnawing pain that does not change with position, and is one type of nerve pain that may be from scarring.
2. Recurrent Stenosis After Decompression Laminectomy for spinal stenosis can cause the bone to grow back and cause another stenosis that leads to recurrent pain. There can be technical problems from decompression surgery such as a missed fragment of bone, incorrect level of surgery, trauma to the nerve root from splitting of the fibers, or inadequate decompression during the original surgery. In this case, there is no postoperative relief and thus a failed surgery.
Discectomy for spinal stenosis can also lead to ongoing problems. In some cases there can be a reherniation of the damaged disc, causing further nerve compression.
Sometimes removing parts of an unstable spine with discectomy or laminectomy procedures can create greater instability in that area.
3. Failure of a Fusion Fusion is trying to make a broken bone heal as bone cells migrate over the damaged bone to form solid bone. It takes about a year for solid bone to be sturdy. Bony fusion can be inhibited by too much movement, screw or rod placement, and the use of NSAIDs. This can lead to breaks and chronic pain. If the level above or below the fusion breaks down, it is called adjacent segment disease. Inflammation of the membranes that surround the nerves of the spinal cord can cause arachnoiditis and leads to pain. In general, if pain relief is experienced in the three months after surgery, the relief will likely continue. However, in 10-20% of cases, the pain continues until the nerve fully heals. Numbness and tingling take longer than pain to go away. The symptoms of arachnoiditis are numbness, tingling, stinging, and burning in the legs. The pain can be so severe as to restrict the ability to walk.
Diagnosing arachnoiditis is difficult, and CT scans and MRIs can help as well as an EMG which is an electromyogram. EMGs detect electrical impulses which can be abnormal in this condition. There is no cure for arachnoiditis and treatment is multidisciplinary using physiotherapy, exercise, and pain management.
4. Post-Fusion ‘Adjacent Segment Disease’ A successful spinal fusion restores height, alignment, and fixes the vertebra in place to alleviate pain. In some cases, this reduction in mobility can lead to increased stress on adjoining spine levels (usually above) which must overcompensate to offer a similar range of motion. Over time this stress can lead to degeneration and wear-and-tear, requiring surgical intervention at the newly damaged level.
In cases of post-fusion adjacent segment disease, it is possible for patients to receive new-generation implants from our German Spine Specialists, such as Artificial Disc Replacement or Facet Replacement, to restore function and best mitigate any transfer of disease to other spine levels.
