Failed Back Surgery Syndrome
Back pain is a widespread public health problem, affecting a staggering 80% of Americans at some point in their lives.1 Each year, an estimated one out of every 14 people will seek medical care for back or neck pain, amounting to almost 14 million visits annually. Estimated annual costs for direct and indirect treatment range from $20 billion to $60 billion.2 Back and/or neck pain is cited as the second most common reason for physician visits, and it is estimated that 25% of all work injuries in the U.S. are related to low back pain.3,4 Most back pain is acute or subacute, with 90% of patients recovering within three to four months.2 However, other estimates suggest less than 30% of patients are completely improved within three months of treatment.5 These more chronic sufferers of back pain endure a cycle of pain that is detrimental to their physical and psychological health, lifestyle, and productivity. Chronic low back pain alone is responsible for the disability or partial disability of at least 7 million Americans. In terms of lost productivity, 93 million lost workdays per year are related to low back pain.6 Diseases of the musculoskeletal system make up the 6th most common reason for hospitalization in the United States, with back surgery (laminectomy) accounting for the most common inpatient, musculoskeletal procedure.7 Surgeons perform an estimated 300,000 to 400,000 back surgeries every year. Annually, neurosurgeons perform at least 100,000 operations for lumbar disc disease alone, and orthopedic surgeons perform a similar number.12 It is estimated that between 20% and 40% of these operations are unsuccessful and result in FBSS.8
Many of these patients undergo additional surgeries in order to correct the situation. However, success rates decrease significantly with each subsequent surgery. After unsuccessful surgery, patients present to chronic pain centers with a much more complicated diagnostic picture. Health care providers treat these patients at chronic pain centers with various medical procedures, counseling, physical therapy, medication, and psychiatric care as needed. However, questions remain about how best to help those who have experienced poor surgery outcomes and how they respond to various modalities of interdisciplinary treatment. For example, injection therapies are an increasingly popular mode of treatment for chronic back pain sufferers. There are, however, little empirical data available to health care providers about how those with a history of unsuccessful surgery respond to injections, particularly within an interdisciplinary treatment program. Furthermore, there are few studies addressing the efficacy of psychotherapy and physical therapy within an interdisciplinary program for patients who have undergone failed back surgeries.
Indications For Spinal Surgery
Surgery represents an important treatment option for physicians in managing chronic back pain, especially conditions that are intractable to more conservative interventions. Except for emergency situations, surgery is only undertaken after attempting less invasive procedures. The most common conditions for which surgery is recommended are disc bulge, disc herniation, and disc disruption; spinal stenosis, spondylosis, spondylolisthesis, and failed back surgery syndrome.
Disc Pathologies (Bulges, Herniation, Disruption)
Disc bulges are a normal part of aging. As we grow older, our discs degenerate and begin to bulge at the sides. This is only problematic when it is coupled with a narrow spinal canal and results in pain from compression of nerve roots.
A disc herniation occurs when the nucleus pulposus pokes out of the annulus wall, causing a compression of nerve roots. The protrusion can stay within the disc or can tear the annulus wall, which can lead to pain via chemical irritation of the outer annulus.9 A severe disc herniation occurs when a fragment of the nucleus pulposus detaches and causes nerve root irritation or travels within the spinal canal.
Disc disruption involves disc degeneration, tearing of the annulus, and subsequent dehydration of the disc material. The most common locations of disc herniations are L4-5 and L5-S1, which account for 98% of lesions.10 Disc herniation usually results in sharp, lancinating pain, and sciatica (radiation down the leg in concert with the anatomic distribution of the affected nerve root). The sciatica can be severe and lead to loss of ambulation. Surgical intervention is typically undertaken when there is profound and/or progressive neurologic deficit present, or when there is incapacitating and severe sciatica or pain that is unresponsive to conservative treatment.
Spinal stenosis is the narrowing of the spinal canal due to degeneration of the facet joints and intervertebral disc spaces. If the narrowing is extreme, compression of the components within the canal will cause lumbar and/or leg pain. Spinal stenosis is a common condition that can be congenital or acquired. Between the ages of 30 and 50, major changes occur in the lumbar spine, including a natural degeneration in the intervertebral discs and facet joints, and narrowing of the spinal canal. Many people who undergo these changes are asymptomatic. Most cases of spinal stenosis do not require surgery, but when pain constantly interferes with ambulation and other treatments do not help, surgery is a viable alternative.10
Spondylolisthesis is a condition in which all or part of a vertebra slips on to another vertebra. There are four major categories of spondylolisthesis that differ to the extent that the top vertebra has slipped onto the lower one. Grades I through IV are divided into percentages of slippage, such that Grade I represents 0% to 25% slippage, and so on. Pain from spondylolisthesis has varied causes. Fracture of the pars interarticularis (the bony structure that connects the upper and lower facet joint of a vertebra), compression of the nerve roots from forward movement of the vertebra, or damage to the lower disk from the vertebra on top may be the cause of pain. Pain from spondylolisthesis is usually characterized by constant low-grade back discomfort that is aggravated by activity and relieved with rest. Sometimes the back pain is accompanied by leg pain, but is typically not incapacitating. In many instances, persons with slippage experience no discomfort and may be unaware of the injury. In those who do experience slippage that is Grade II or worse, and whose pain does not respond to less invasive treatments, surgical fusion or decompression is recommended.9,10