Geriatrics Guide

Under rules promulgated by Titles II and XVI of the United States Social Security Act, spinal stenosis is recognized as a disabling condition under Listing 1.04 C. The listing states: “Lumbar pseudoclaudication, established by findings on appropriate medically acceptable imaging, manifested by chronic nonradicular pain and weakness, and resulting in inability to ambulate effectively, as defined in 1.00B2b.” 1.00B2b states, “b. What we mean by Inability to Ambulate Effectively. (1) Definition. Inability to ambulate effectively means an extreme limitation of the ability to walk; i.e., an impairment(s) that interferes very seriously with the individual’s ability to independently initiate, sustain, or complete activities. Ineffective ambulation is defined generally as having insufficient lower extremity functioning (see 1.00J) to permit independent ambulation without the use of a hand-held assistive devices(s) that limits the functioning of both upper extremities. (2) To ambulate effectively, individuals must be capable of sustaining a reasonable walking pace over a sufficient distance to be able to carry out activities of daily living. They must have the ability to travel without companion assistance to and from a place of employment or school. Therefore, examples of ineffective ambulation include, but are not limited to, the inability to walk without the use of a walker, two crutches or two canes, the inability to walk a block at a reasonable pace on rough or uneven surfaces, the inability carry out routine ambulatory activities, such as shopping and banking, and the inability to climb a few steps at a reasonable pace with the use of a single hand rail. The ability to walk independently about one’s home without the use of assistive devices does not, in and of itself, constitute effective ambulation.”

Note that the regulation is written specifically for lumbar stenosis. Inclusion of cervical stenosis requires either a meet or equal depending on the idiosyncrasy of the trier of fact in federal disability hearings. [177] [178]

A Spanish study noted that following lumbar disc surgery, or lumbar spine surgery in general, several chronic pain syndromes can result, either in the lumbar region or the lower limbs. The current indication for spinal surgery is to relieve chronic pain in the degenerative spine (degenerative disc disease and lumbar stenosis) which causes symptoms of pain in the legs. A review of the methodology of evidence based medicine shows that the use of spinal fusion, instrumentation, and decompression laminectomy have not answered the problem of chronic pain, despite more than 20 years experience. Neuro-modulation techniques described as spinal electronic stimulation techniques or injections in the dural sac. These may be of benefit in the chronic pain patient, as an alternative to more surgery, in the face of failed surgery. [176] Once the patient is deemed to need the placement of a neurostimulator, or a transcutaneous nerve stimulator (TENS), the condition is quite poor and highly impaired. The outlook for such patients is usually quite guarded.

It has been recognized for many years that spinal surgery can be complicated by recurrence of the same symptoms which originally provided the indications for the initial surgery. Decompressive laminectomy remains the mainstay of operative treatment for stenosis of the spine, whether it is combined with fusion or not. Failure of fusion can lead to a condition called pseudoarthosis. Repeat surgery to repair a pseudarthrosis has been documented in the surgical literature to be futile for decades. Despite this, there remains a school of thought which continues to recommend repeat surgery for repair of failed fusion. [158] [159] There has never been an established link between pseudarthrosis and recurrent back pain. [160] Scar tissue frequently fills in the area of laminectomy creating a new stenotic condition. The nerve roots can become encased in scar tissue, causing new, painful symptoms. It has been long recognized that neurolysis (a surgery to remove the scar tissue from the dura and nerve roots) is futile, and will only lead to more scar tissue. [161] [162] [163] [164][165] [166]

Recurrent or multiple surgeries in the lumbar spine quickly lead to successively worsening results. When surgery is carried out in the worker’s compensation system, it is even worse. [167] The development of arachnoiditis, a chronic and often non-specific inflammation of the epidural space can be particularly vexing to the treating physician.

Recent studies have shown that cigarette smokers with routinely fail all spinal surgery, if the goal of that surgery is the decrease of pain and impairment. Many surgeons consider smoking to be an absolute contraindication to spinal surgery. Nicotine appears to interfere with bone metabolism through induced calcitonin resistance and decreased osteoblastic function. It may also restrict small blood vessel diameter leading to increased scar formation. [168] [169] [170] [171] [172] [173] [174] [175]

Most failed back syndrome patients who have had two or more surgeries will become chronic pain patients, addicted or habituated to heavy narcotics, unemployed and experiencing a limited social existence.

A 41 year old welder fell approximately 8 feet onto a concrete surface at a construction site where he was working. He landed on his back and buttocks. He immediately experienced low back pain and leg pain. He ignored it for the rest of the day. He tried to continue working, but over the next two weeks, his pain in the back became worse, and his legs began to go numb for several hours at a time. He filed a comp claim and was sent to the company doctor who referred him to a spinal surgeon. There, he was diagnosed with L2-3, L3-4 and L4-5 spinal stenosis. It was felt this had been a previously undiagnosed and asymptomatic condition which had been aggravated by the fall. Since his symptoms were not improving after a few months, a decompressive laminectomy was advised. He underwent the surgery. On the fourth post-op day, he spiked a fever of 102 degrees F. His white count was 13,500. He appeared in some distress. His sed rate was 110 mm/hour. His wound in the lumbar spine was red and draining pus. It had a foul, fecal odor to it. A diagnosis of wound infection was made, and he was returned to surgery where the wound was opened, drained and irrigated. Cultures grew methicillin sensitive staphylococcus aureus and streptopeptcoccus. Two more surgeries were necessary, along with a two month course of intravenous antibiotics. He was cured of the infection after two months. He continued to have sharp and unrelenting pain in his back and radiating into his legs. Severely impaired from his pain, at two years he was still unemployed and maintained on the oral narcotics morphine sulphate, 80 mg. per day supplemented with oxycontin and percocet for breakthrough pain. he was now diagnosed as a failed back syndrome.

Post operative infection in the site of the dural canal is relatively infrequent, reported in the surgical literature to be 1% to less than 12%. [135] [136] [137] [138] [139] [140] [141] [142] [143] [144] [145] [146] [147] [148] [149] [150] The longer the surgical procedure, and the more complicated, the greater the risk of infection. When it occurs, it is usually a devastating complication, if the space around the dural canal is involved, and will leave the patient with significant permanent impairment. Previous wound infection should be considered as a contraindication to any further spinal surgery, since the likelihood of improving such patients with more surgery is small. [151] [152] [153] [154] [155] [156] Antimicrobial prophylaxis (giving antibiotics during or after surgery before an infection begins) reduces the rate of surgical site infection in lumbar spine surgery, but a great deal of variation exists regarding its use. In a Japanese study, utilizing the Center for Disease Control recomendations for antibiotic prophylaxis, an overall rate of 0.7% infection was noted, with a single dose antibiotic group having 0.4% infection rate and multiple dosage antibiotic infection rate of 0.8%. The authors had previously used prophylactic antibiotics for 5 to 7 postoperative days. Based on the Center for Disease Control guidelines, their antibiotic prophylaxis was changed to the day of surgery only. It was concluded there was no statistical difference in the rate of infection between the two different antibiotic protocols. Based on the CDC guideline, a single dose of prophylactic antibiotic was proven to be efficacious for the prevention of infection in lumbar spine surgeries. [157]

The biggest risk of spinal stenosis surgery is that it might not be effective in relieving the symptoms. Compared to surgery for disc herniation and radiculopathy, spinal stenosis surgery has a greater effectiveness. The beneficial results of the surgical decompression may deteriorate with time. This can lead to a recurrence of symptoms, or the development of new ones. In the most common forms of degenerative stenosis, the pathology is characterized pathologically by degenerative hypertrophy of the facet joints, the vertebral body margins, thickening of the ligamentum flavum and narrowing of the discs with osteophyte formation. [133] The combined effect of these changes is a narrowing of the canal with leg pain, paresthesias, varying degree of back pain and limitation of walking distance with a good peripheral circulation. The lower limb pain is increased by bending forward. The incidence of unsatisfactory results after surgery for lumbar stenosis is not known. Despite studies which describe a “good” or “excellent” result, the parameters are not the same for different studies. Many studies rely upon a third party filling out a questionnaire. Some patients are lost to follow-up. Most studies never look at such important factors as “return to previous work”, “use of narcotics” or “ability to reenter the competitive work force”. Therefore, there is no correlation between reported results and ability to return to work. [134]

In a landmark Canadian study, Waddell et al. found that in the worker’s compensation system, once the threshold of two major spinal surgeries is reached, the vast majority of workers will never return to any form of gainful employment. Beyond two spinal surgeries, any more are likely to make the patient worse, not better. Very few studies in the worldwide surgical literature actually document return to work after spinal surgery, or lack thereof. [132]

38 year old male truck driver was injured when his truck inadvertently drove over a large pot hole which was about 2 feet deep. He experienced a jarring sensation in his back. This progressed to generalized leg pain. He was diagnosed with a stenotic segment at L3-4. After six months he underwent a surgical decompression. This relieved his symptoms for about six months. He returned to truck driving, when his symptoms returned. He underwent another surgical procedure with removal of scar from the previous laminectomy and posterior fusion with metal placement. He was never able to return to work, and developed a chronic pain syndrome with consumption of large amounts of prescribed narcotics on a daily basis. At three years post op, he was diagnosed with arachnoiditis of the lumbar spine. He was given a series of steroid epidural injections, but without any lasting benefit. Finally, he had a third surgery for placement of a spinal cord stimulator. This reduced his perception of pain by about 25%, but he continued with the same consumption of narcotics as before surgery. He was now diagnosed as a failed back syndrome.

42 year old with spinal stenosis was injured on the job. He was lifting boxes while sorting inventory at a store. The boxes weighed about 30 pounds each. He experienced low back pain which then became a diffuse numbness in the legs. It persisted for two months. He was referred to a spinal surgeon who diagnosed multilevel stenosis between L2 and S1. He was given a series of steroid epidural injections over a three month period. These provided relief for about six months, but then his symptoms returned, when it was decided he should undergo an extensive decompression from L2 to S1.

In a study of steroid epidural injections, the authors noted that spinal stenosis is one of the three most common diagnoses of low back and leg symptoms which also include disc herniation and degenerative spondylolisthesis. Spinal stenosis is a narrowing of the spinal canal with encroachment on the neural structures by surrounding the bone and soft tissue. In the United States, one of the most commonly performed interventions for managing chronic low back pain are epidurual injections, including their use for spinal stenosis. However, there have been no randomized trials and evidence is limited with regards to the effectiveness of epidural injections in managing chronic function limiting low back and lower extremity pain secondary to lumbar spinal stenosis. The study found caudal epidural injections with or without steroids may be effective in patients with chronic function-limiting low back and leg pain with associated spinal stenosis in approximately 60% of patients. [131]