Lumbar Spinal Stenosis: Treatment

One nonrandomized comparison suggested that 60% of surgically treated patients improved, compared with 30% of those treated nonsurgically (25). Improvement was measured by walking capacity, level of pain, and use of analgesics. The follow-up was 31 months in the nonsurgical patients and 53 months in the surgical patients.

Findings: one third of the surgically treated patients and one half of the nonsurgical patients still had neurogenic claudication at the end of follow-up. By visual analogue scale estimation, 60% of the surgically treated patients and 33% of the nonsurgical patients felt better; 58% of the nonsurgical patients were unchanged.

A nonrandomized prospective cohort study over 10 years concluded that the outcome was most favorable with surgical treatment; however, a substantial number of patients also responded to conservative (.ie., nonsurgical) treatment (18). Though 70% of conservatively treated patients reported satisfactory results at 6 months, at 4 years this number had declined to 57%. The authors concluded that an initial nonsurgical approach was advisable for most patients.

Nonsurgical Management
Components of nonsurgical treatment may include activity restrictions, physical therapy, analgesics, anti-inflammatory medications, lumbosacral orthoses, epidural injection, and calcitonin. These therapies have not been compared in any randomized controlled trial, and there is considerable variability among practitioners in their use.

A reasonable approach is to use a stepwise treatment pathway that progresses from least invasive treatments (activity modification, orthoses, physical therapy) to most invasive (epidural injection) (34).

Physical therapy
Although physical therapy is often the first recommended form of treatment for persons with spinal stenosis, few studies have closely examined the effect of specific exercise programs on functional outcome.

Generally, active exercise in the form of stretching, strengthening, or aerobic fitness training is recommended. Active exercise may help increase lumbopelvic muscular stabilization, maintaining better posterior pelvic tilt (35). It may also help by improving cardiovascular conditioning and enhancing "soft-tissue function" (strength and flexibility of muscles, ligaments, and tendons).

In an uncontrolled prospective trial, (36) we examined the effects of a McKenzie-based exercise approach in 36 patients with spinal stenosis. The McKenzie approach consists of developing a set of patient-specific exercises based on the response of the individual symptoms to repeated end-range spinal movements in various planes and correcting postural deficiencies (37). Significant improvement was defined as at least 50% improvement in at least two of four outcome variables at 12 weeks: pain score, Roland disability score, walking distance, and standing time. The results suggest that, at least in some patients with symptomatic spinal stenosis, an active, customized physical therapy program may produce significant benefit.

Exercises that encourage lumbar flexion and flattening of the lumbar lordotic curve can be of a clinical benefit to patients suffering from lumbar spinal stenosis. Physical therapy may be prescribed with the goals of improving strength, endurance, and flexibility.

NSAIDs and analgesics
Nonsteroidal anti-inflammatory drugs (NSAIDs) and analgesics are sometimes used to treat symptoms of spinal stenosis, though comparative studies demonstrating efficacy in this patient group are not available.

In addition, many patients with spinal stenosis are at relatively high risk for NSAID toxicity in view of their age and comorbid medical problems, such as hypertension and cardiovascular disease. Furthermore, there is no clear rationale for an anti-inflammatory agent in most patients with degenerative spinal stenosis.

Studies comparing acetaminophen and ibuprofen or naproxen in degenerative arthritis of the knee have not demonstrated significant differences in outcome, but similar trials have not been conducted in patients with lumbar canal stenosis.38

In the absence of data to show that NSAIDs are superior to simple analgesics such as acetaminophen, the risk of NSAID toxicity is the determining factor in therapeutic decision-making. NSAIDs are strongly contraindicated in patients with a history of congestive heart failure, peptic ulcer, or kidney disease. If an NSAID is used, frequent clinical and laboratory monitoring for adverse renal or gastrointestinal reactions is mandatory.

Long-term opioid therapy should be considered in some patients with spinal stenosis who have had an unsatisfactory response to other medical therapies and who are not surgical candidates. Comorbidity and frailty may limit the usefulness of physical therapy and NSAIDs and increase the risk of surgical therapy, particularly in older patients. In such patients, a careful trial of low-dose opioids is reasonable, (39) with the following caveats:

•Assess for pain control and functional improvement, i.e., in walking, standing, and self-care activities.

•The possibility that chronic use of opioids may adversely affect cognition, particularly in the older patient, is not well studied. Until you can establish that an older patient is not experiencing any cognitive deficit, he or she must be advised to avoid driving and take measures to prevent falls and accidents.

•Constipation is a universal side effect of opioids, and a preventive program should be initiated at the onset of opioid therapy.

•Though physical dependence occurs with long-term opioid therapy, addictive behavior is exceedingly rare, particularly in this subset of patients (40).

Calcitonin
Several small clinical trials reported beneficial effects of calcitonin in patients with spinal stenosis (41-44). Improvement in both pain and walking tolerance has been described. The beneficial effects were usually apparent within 4 to 6 weeks.

However, a recently completed doubleblind, randomized, placebo-controlled trial was unable to demonstrate clinical effectiveness of calcitonin administered by nasal spray in persons with spinal stenosis (D.J. Mazanec et al, unpublished data 2002).

Though calcitonin's mechanism of action is unknown, some speculate that it acts nonspecifically by raising the level of endogenous opioids (beta endorphins) (45,46). Alternatively, others have suggested that calcitonin may improve symptoms by enhancing circulation to an ischemic cauda equina (42).

Flushing or nausea, the two main side effects, are seen in fewer than 5% of patients treated with calcitonin.

Epidural corticosteroid injection
Though epidural steroid injection is often suggested for control of severe radicular symptoms in patients with spinal stenosis, data supporting its efficacy are lacking.

Ciocon et al (47) did evaluate the effectiveness of caudal epidural injection in elderly patients with spinal stenosis and concluded that significant pain relief could be achieved. Based on a five-point rating scale, pain improved from a mean of 3.4 to 1.5 and was relieved for up to 10 months.

In most other studies of epidural corticosteroid injection, patients with spinal stenosis were intermingled with patients with other radicular syndromes, making it difficult to assess the outcomes. No randomized controlled trial has been performed.