When chronic back or leg pain persists despite surgical intervention, patients may be diagnosed with Post Laminectomy Syndrome (PLS). A laminectomy involves removing the bony plate of the vertebra (the lamina) to decompress the spinal cord or nerves and alleviate pain. While many individuals experience relief after this surgery, a significant portion does not, leading to the continuation or return of their pain. PLS represents this outcome, where the procedure fails to provide the expected lasting relief. This syndrome affects an estimated 20% of patients who undergo spinal surgery.
Defining Post Laminectomy Syndrome
Post Laminectomy Syndrome is a chronic pain state that develops after one or more back surgeries, typically a laminectomy, where the pain is either unchanged, returns, or worsens. The condition is characterized by pain that persists beyond the expected healing period, generally considered to be three to six months post-operation. A laminectomy is a decompression surgery performed to enlarge the spinal canal, relieving pressure on the spinal cord or nerve roots, often due to spinal stenosis or a disc herniation.
The persistence of pain after spinal decompression surgery is why PLS is considered a subset of Failed Back Surgery Syndrome (FBSS). FBSS is defined as lumbar spinal pain that either persists after or appears following a surgery meant to address spinal pain in that area. It is important to distinguish this chronic condition from the acute pain experienced during the immediate post-operative recovery phase.
Factors Contributing to PLS Development
The development of PLS rarely stems from a single cause, often involving a combination of mechanical, physiological, and non-physical factors. Mechanical issues include technical failure, such as inadequate initial decompression, or leaving a residual disc fragment or bone spur that irritates the nerve. Structural problems can also arise, including recurrent disc herniation or the deterioration of the spinal segment adjacent to the surgical site, known as adjacent segment disease.
The spine may also become unstable following the removal of the lamina if a spinal fusion was not performed, leading to abnormal movement and subsequent pain. A significant biological cause is the formation of epidural fibrosis, or scar tissue, which naturally occurs during healing. This scarring can sometimes wrap around and compress the nerve roots, causing ongoing neural tension and pain.
Non-physical factors also influence the chronic nature of PLS, as pain is significantly influenced by a person’s psychological state. Conditions like pre-existing depression, anxiety, or high stress levels are associated with a higher likelihood of developing persistent pain after surgery. Furthermore, lifestyle factors such as smoking can interfere with bone metabolism and wound healing, contributing to poor outcomes.
Recognizing the Signs and Symptoms
The presentation of PLS centers on chronic pain in the area of the back surgery and often the extremities. Patients typically report a persistent, dull, and aching pain in the low back, which may be similar to or worse than the pain felt before the operation. This axial spinal pain is often accompanied by radiating pain, or sciatica, that travels down the buttocks and legs.
The pain often includes neuropathic elements, described as sharp, pricking, stabbing, or electric-like sensations in the extremities, indicating continued nerve irritation. Patients may also experience associated neurological deficits, such as numbness, tingling, and muscle weakness. These symptoms can lead to difficulty performing daily activities and restricted mobility.
Managing Post Laminectomy Syndrome
Treatment for PLS requires a comprehensive, multidisciplinary approach focused on managing chronic pain. Non-surgical management is the primary strategy, often starting with a combination of physical therapy and medication. Physical therapy aims to improve spinal flexibility and strength, while medications may include anti-inflammatory drugs, muscle relaxants, and nerve-specific agents like anticonvulsants or certain antidepressants to address neuropathic pain.
Interventional procedures can provide targeted relief for specific pain generators in the spine. These include epidural steroid injections, which deliver anti-inflammatory medication near the nerve roots, and radiofrequency ablation, which uses heat to temporarily interrupt pain signals. For more persistent pain, advanced neuromodulation techniques are often considered.
Spinal Cord Stimulation (SCS) is a well-established therapy for PLS where an implanted device delivers mild electrical pulses to mask pain signals before they reach the brain. This technique is effective for reducing chronic neuropathic pain that has failed to respond to other treatments. Revision surgery is generally reserved as a last resort due to the complexity of re-operating on scarred tissue and the potential for limited improvement.