Lumbar spine stenosis: a common cause of back and leg pain

Lumbar spine stenosis most commonly affects the middle-aged and elderly population. Entrapment of the cauda equina roots by hypertrophy of the osseous and soft tissue structures surrounding the lumbar spinal canal is often associated with incapacitating pain in the back and lower extremities, difficulty ambulating, leg paresthesias and weakness and, in severe cases, bowel or bladder disturbances. The characteristic syndrome associated with lumbar stenosis is termed neurogenic intermittent claudication. This condition must be differentiated from true claudication, which is caused by atherosclerosis of the pelvofemoral vessels. Although many conditions may be associated with lumbar canal stenosis, most cases are idiopathic. Imaging of the lumbar spine performed with computed tomography or magnetic resonance imaging often demonstrates narrowing of the lumbar canal with compression of the cauda equina nerve roots by thickened posterior vertebral elements, facet joints, marginal osteophytes or soft tissue structures such as the ligamentum flavum or herniated discs. Treatment for symptomatic lumbar stenosis is usually surgical decompression. Medical treatment alternatives, such as bed rest, pain management and physical therapy, should be reserved for use in debilitated patients or patients whose surgical risk is prohibitive as a result of concomitant medical conditions.     

Morphogenesis of the spinal canal, normal and stenotic

The closest formative developmental dependence of the axial skeleton upon the morphogenesis of the intraspinal nervous structures is reflected in the roentgen features of the individual vertebrae as well as of the vertebral column in its entirety. The vertebroneural developmental events are characterized by a steady relative decrease in size of the nervous structures (the first to be laid down and huge in the embryonic period) under a corresponding increase in size of the skeletogenic tissues. There exists experimental evidence that the maintenance of the necessary developmental balance between the two tissues, the bony and the skeletogenic, is a function of the nervous substance. The tight spinal canal appears to result from a failure of the latter neural function leading to overgrowth of the bony structures, viz., to massive vertebrae and laminae encroaching upon the neural contents. Morphogenesis of the normal and tight lumbar spinal canal is discussed with special reference to the developmental interrelations between the cauda equina complex and the lumbar vertebrae.     

Thoracic spinal stenosis: diagnostic and treatment challenges

Thoracic stenosis may be defined by a narrowing of the anteroposterior (AP) diameter of the thoracic spinal canal to < 10 mm. Primary thoracic stenosis, documented when myelography is carried beyond the thoracolumbar junction into the upper thoracic canal, is most frequently associated with lumbar stenosis, whereas secondary stenosis, attributed to endocrinopathies and systemic diseases, more typically involves the entire spinal canal. Recognition of the presence of primary or secondary thoracic stenosis and the entire extent of attendant disease in the adjacent cervical or lumbar regions is essential to proper surgical management. Nine cases of primary and one instance of secondary thoracic spinal stenosis were reviewed. Seven of nine patients with primary thoracic stenosis had accompanying lumbar involvement, whereas one patient with secondary stenosis attributed to acromegaly had cervical, thoracic, and lumbar stenosis.     

A new approach in the treatment of hypotension in human septic shock by NG-monomethyl-L-arginine, an inhibitor of the nitric oxide synthetase

Between 1987 and 1991, 33 patients with spinal stenosis of the lumbar spine were treated by decompression (33 patients) and posterior fusion (30 patients). Indication for decompression was based on case history and lumbar myelography with flexion/extension views. At follow-up 1-5.5 years later, 28 patients were happy with the results of the treatment and would be willing to be operated on again in a similar situation. Two other patients also presented objectively good results, but were dissatisfied for reasons not related to the operation. Our study shows that myelography and case history are adequate investigations for determination of the level of pathology and for making a decision about operative decompression in spinal stenosis of the lumbar spine. CT or MRI are only needed if the symptoms of the patient are not explained by the myelogram. Although MRI is advocated as the investigation of first choice for lumbar spinal stenosis, we still prefer the myelography, which is easier to interpret during the operation. Our study also shows that operative treatment of spinal stenosis is very rewarding, since 9 out of 10 patients will have good results. We usually combine decompression and fusion. Decompression alone is only performed in patients without any back pain and with stable motion segments after adequate decompression.     

Lumbar spinal stenosis: a review of current concepts in evaluation, management, and outcome measurements

The purpose of this review is to present current information from the literature regarding the pathoanatomy, clinical presentation, differential diagnosis, treatment, and outcome assessment methods for patients with lumbar spinal stenosis. Lumbar spinal stenosis is a frequently encountered condition, particularly in the elderly. Treatment requires an accurate diagnosis, but differential diagnosis of lumbar stenosis can be difficult. The literature to date has focused primarily on surgical treatment. The long-term efficacy of surgery has been questioned, and surgical procedures are associated with increased costs and risks of morbidity in an elderly population. A trial of conservative care is recommended in most cases, but there are presently no randomized controlled studies in the literature comparing surgical versus conservative management, or evaluating the effectiveness of any specific conservative treatment approach. The existing literature has further been criticized for having poorly defined outcome measures. The assessment of treatment outcomes should be multifactorial, including measures of pathoanatomy and impairments, as well as patient-centered measures such as level of disability, patient expectations, and satisfaction. The present level of understanding of lumbar spinal stenosis is deficient in many areas, including differential diagnosis, treatment, and outcome assessment. Future research should address these deficits to improve the management of patients with this condition.     

Two-level spinal stenosis in minipigs. Hemodynamic effects of exercise

STUDY DESIGN: Twenty-two G?ttingen minipigs were trained to run on a treadmill. Two-level lumbar spinal stenosis was created in 12 pigs, 10 were unoperated control subjects. Blood flow of the spinal cord and nerve roots was determined with microspheres at rest, during exercise, and after exercise. OBJECTIVES: To study the effect of lumbar spinal stenosis and exercise on blood flow of spinal neural tissue. SUMMARY OF BACKGROUND DATA: Neurogenic claudication, the key symptom of lumbar spinal stenosis, may be caused by vascular impairment or mechanical distress of neural tissue during exercise. Experimental compression of the cauda equina causes reversible nerve root edema, stasis, blood flow decrease, and compromised neural function. The vascular pathophysiology of spinal stenosis during exercise has not been studied previously. METHODS: Pigs were trained daily for 3 months. Two-level 25% lumbar spinal stenosis was introduced by placement of stenosing bands around the dural sac. Neurologic function was monitored before surgery by evoked potentials and after surgery by the Tarlov score. Regional blood flow in lumbosacral neural tissue was measured 3 days after chronic catheterization using microspheres at rest, during exercise at 3 km/h for 15 minutes, and at rest 30 minutes after exercise. RESULTS: Blood flow of grey and white matter increased during exercise in both groups, with no differences between groups. slight hyperemia prevailed after exercise in white matter of the stenotic area but not in grey matter. Nerve root blood flow was largely unchanged in control subjects during exercise but was reduced in spinal stenosis at rest, further depressed during exercise, and normalized after exercise. Dural blood flow was elevated throughout. CONCLUSION: The study suggests that exercise-induced impairment of spinal nerve root blood flow plays a role in the pathophysiology of neurogenic claudication.     

Can transplantation of neurons facilitate motor recovery in paraplegics? Study of an animal model

This review strives forward at least two goals. First, to take from the literature the arguments demonstrating that hindlimbs locomotion is controlled by a spinal network of neurons (the so-called Central Pattern Generator for locomotion--CPG) known to be able to generate locomotor activity independently of the control of supraspinal nervous structures, as it is after thoracic lesions of the spinal cord. The principles of work of the CPG and its intrinsic possibilities to adapt its working are reviewed. Special reference is made to the various ways used during experiments to activate the CPG in spinal animals or clinical practice in paraplegic men: training to walk, electrical stimulations, pharmacological stimulations. Second, to show, from our own results, obtained from the study of an animal model of paraplegia, the adult spinal rat, how it could be possible to take advantage of the autonomy of the CPG, with special reference to its sensibility to monoamines, to obtain locomotor recovery in hindlimbs after section of the thoracic spinal cord, by means of transplantation of noradrenergic and/or serotonergic embryonic neurons in the lumbo-sacral spinal cord. Section of the spinal cord at a thoracic level results in an important locomotor deficit in hindlimbs, likely linked to degeneration of monoaminergic terminals in the lumbar enlargement. In the adult spinal rat, sub-lesional injection of a suspension of embryonic nervous cells, taken from either locus coeruleus or raphe sites, leads to reinnervation of the lumbar enlargement with monoaminergic terminals. Despite the fact that connections with supraspinal structures are not reestablished, transplanted animals recover progressively a posture convenient for locomotion. The hindlimbs, which are in an extended position a few days after the lesion, become progressively flexed and able to support the body weight. This evolution does not appear in spinal but non transplanted animals. But, the main point is that transplanted animals develop, within the few weeks that follow transplantation, a good-quality locomotor activity in hindlimbs which had no equivalent in spinal but non transplanted animals. The reality of a lumbar CPG for locomotion and the efficacy of pharmacological treatments and training to walk, to elicit recovery of stepping, are discussed in man, in connection with the relevance to use transplantation of monoaminergic nervous cells in the spinal cord of paraplegics.     

Dimensions of the lumbar spinal canal: variations and correlations with somatometric parameters using CT

The aim of this study was to investigate the correlation of vertebral dimensions with somatometric parameters in patients without clinical symptoms and radiological signs of central lumbar spinal stenosis. One hundred patients presenting with low back pain or sciatica were studied with CT. In each of the L3, L4 and L5 vertebra three slices were taken with the following measurements: 1. Slice through the intervertebral disc: (a) spinal canal area; (b) interarticular diameter; (c) interligamentous diameter. 2. Slice below the vertebral arcus: (a) dural sac area; (b) vertebral body area. 3. Pediculolaminar level: (a) anteroposterior diameter and interpedicular diameter of the spinal canal; (b) spinal canal area; (c) width of the lateral recesses. The Jones-Thomson index was also estimated. The results of the present study showed that there is a statistically significant correlation of height, weight and age with various vertebral indices. The conventional, widely accepted, anteroposterior diameter of 11.5 mm of the lumbar spinal canal is independent of somatometric parameters, and it is the only constant measurement for the estimation of lumbar spinal stenosis with a single value. The present study suggests that there are variations of the dimensions of the lumbar spinal canal and correlations with height, weight and age of the patient.     

Lumbar spinal canal stenosis associated with progressive degenerative changes of the spine. A case report

STUDY DESIGN: Case report. OBJECTIVES: To report a case of spinal canal stenosis associated with progressive degenerative changes of the lumbar spine. SUMMARY OF BACKGROUND DATA: As far as the authors are aware, there has been no similar case reported. METHODS: The clinical features of the case are reported, and the pathology is discussed. RESULTS: In a 40-year-old man, spinal canal stenosis developed, associated with progressive degenerative changes of the lumbar spine. The man underwent posterior decompression and fusion using pedicle screws. The surgical results were satisfactory at the time of writing this report. CONCLUSIONS: This case presented a peculiar clinical course, which could not be categorized under previously reported disorders. It may be a new disease entity of spinal canal stenosis. The surgical outcome was satisfactory 2 years, 6 months after surgery.     

Plasma adrenaline responses to long-term modification of blood pressure in normotensive rats and hypertensive rats

After one extradural injection of 0.25% bupivacaine 0.3 ml and 3H-bupivacaine 0.005 mCi in multilamellar liposomes, no systemic radioactivity (plasma, liver, heart muscle) was obtained for 1 h, and the labelling was less than that of systemic distribution of plain bupivacaine for the following 3 h. In contrast, radioactivity in the lumbar spinal nerves peaked in the first hour and remained higher than that of plain bupivacaine for 4 h. No radioactivity was measured in cerebrospinal fluid. Small unilamellar vesicles incorporating 3H-cholesterol did not significantly label spinal nerves and central nervous structures indicating that the mode of action of liposomal bupivacaine did not involve uptake by nerve structures. Rapid uptake of radioactivity by spinal nerves suggested exchange of bupivacaine between liposomes and nerve sheaths.     

Developmental lumbar spinal stenosis. Pathology and surgical treatment

The purpose of this presentation is to outline the extent of surgical resection necessary for complete decompression of the neural elements in spinal stenosis and to introduce a system for the evaluation of disability in patients with spinal stenosis. Sixteen patients with the confirmed diagnosis of lumbar spinal stenosis were evaluated by the system. Ten cases were treated surgically. Indications for operative treatment were 1) intolerable pain in average daily living, 2) progressively worsening or significant degree of motor weakness, and 3) sphincter dysfunction. Satisfactory results from operative treatment were expected only after adequate and thorough decompression. The extent of surgical decompression was determined by clinical evaluation, myelographic examination, and by the type of disease process exhibited. The most common cause of unsatisfactory results was inadequate decompression of spinal contents. The extent of adequate decompression is described according to three different variations of pathologic anatomy of spinal stenosis: a) concentric contraction of the spinal canal, b) sagittal flattening of the spinal canal, and c) stenosis caused by anomalous articular process(es). No excellent results were obtained even after thorough and adequate decompression of spinal contents.     

Dynamic effects on the lumbar spinal canal: axially loaded CT-myelography and MRI in patients with sciatica and/or neurogenic claudication

STUDY DESIGN: In patients with sciatica or neurogenic claudication, the structures in and adjacent to the lumbar spinal canal were observed by computed tomographic myelography or magnetic resonance imaging in psoas-relaxed position and during axial compression in slight extension of the lumbar spine. OBJECTIVES: To determine the mechanical effects on the lumbar spinal canal in a simulated upright position. SUMMARY OF BACKGROUND DATA: For years, functional myelographic investigation techniques were shown to be of value in the evaluation of suspected encroachment of the spinal canal. Since the advent of computed tomography and magnetic resonance imaging, there have been few clinical and experimental attempts that have imitated these techniques. The data indicate that the space within the canal is posture dependent. METHODS: Portable devices for axial loading of the lumbar spine in computed tomographic and magnetic resonance examinations were developed. Fifty patients (94 sites) were studied with computed tomographic myelography, and 34 patients (80 sites) with magnetic resonance in psoas-relaxed position followed by axial compression in slight extension. The dural sac cross-sectional area at L2 to S1, the deformation of the dural sac and the nerve roots, and the changes of the tissues surrounding the canal were observed. RESULTS: In 66 of the investigated 84 patients, there was a statistically significant reduction of the dural sac cross-sectional area in at least one site during axial compression in slight extension. Of the investigated patients, 29 passed the borderlines for relative (100 mm2) or absolute stenosis (75 mm2) in 40 sites. In 30 patients, there was deformation of the dural sac in 46 sites. In 11 of the patients investigated with magnetic resonance imaging, there was a narrowing of the lateral recess in 13 sites, during axial compression in slight extension. CONCLUSIONS: Axial loading of the lumbar spine in computed tomographic scanning and magnetic resonance imaging is recommended in patients with sciatica or neurogenic claudication when the dural sac cross-sectional area at any disc location is below 130 mm2 in conventional psoas-relaxed position and when there is a suspected narrowing of the dural sac or the nerve roots, especially in the ventrolateral part of the spinal canal in psoas-relaxed position. The diagnostic specificity of the spinal stenosis will increase considerably when the patient is subjected to an axial load.     

Spinal subdural haematoma: an unusual complication of lumbar puncture

A case in which a spinal subdural haematoma obscured the diagnosis of spinal stenosis is described. The haematoma resulted as a complication of the lumbar puncture necessary for the myelogram. No other aetiological factors were found, but it is suggested that this condition may become more frequent as the result of iatrogenic haemostatic defects.     

1997 Volvo Award winner in clinical studies. Degenerative lumbar spondylolisthesis with spinal stenosis: a prospective, randomized study comparing decompressive laminectomy and arthrodesis with and without spinal instrumentation

STUDY DESIGN: This prospective study analyzed the influence of transpedicular instrumented on the operative treatment of patients with degenerative spondylolisthesis and spinal stenosis. OBJECTIVES: To determine whether the addition of transpedicular instrumented improves the clinical outcome and fusion rate of patients undergoing posterolateral fusion after decompression for spinal stenosis with concomitant degenerative spondylolisthesis. SUMMARY OF BACKGROUND DATA: Decompression is often necessary in the treatment of symptomatic patients who have degenerative spondylolisthesis and spinal stenosis. Results of recent studies demonstrated that outcomes are significantly improved if posterolateral arthrodesis is performed at the listhesed level. A meta-analysis of the literature concluded that adjunctive spinal instrumentation for this procedure can enhance the fusion rate, although the effect on clinical outcome remains uncertain. METHODS: Seventy-six patients who had symptomatic spinal stenosis associated with degenerative lumbar spondylolisthesis were prospectively studied. All patients underwent posterior decompression with concomitant posterolateral intertransverse process arthrodesis. The patients were randomized to a segmental transpedicular instrumented or noninstrumented group. RESULTS: Sixty-seven patients were available for a 2-year follow-up. Clinical outcome was excellent or good in 76% of the patients in whom instrumentation was placed and in 85% of those in whom no instrumentation was placed (P = 0.45). Successful arthrodesis occurred in 82% of the instrumented cases versus 45% of the noninstrumented cases (P = 0.0015). Overall, successful fusion did not influence patient outcome (P = 0.435). CONCLUSIONS: In patients undergoing single-level posterolateral fusion for degenerative spondylolisthesis with spinal stenosis, the use of pedicle screws may lead to a higher fusion rate, but clinical outcome shows no improvement in pain in the back and lower limbs.     

A study on temperature dependent vestibular potential: effect of long lasting thermal stimulus and aminoglycoside agent

High power drill systems are being used for cervical and lumbar spinal stenosis surgeries. The use and comparative analysis of several systems are presented.     

Lumbar spinal stenosis in an elderly patient

BACKGROUND: The general population is aging, and lumbar stenosis is one of the more frequent conditions observed in an orthopedic or neurosurgical practice. METHODS: This case presentation is of an 86-year-old male who developed lumbar spinal stenosis with a progressive neurologic deficit that caused severe leg pain, affected bladder function, and affected gait. Relevant medical literature is reviewed. RESULTS: Bladder function and gait returned after spinal surgery, and this patient's pain was greatly reduced. A multidisciplinary team applied therapy after surgery. The medical literature does not concentrate solely upon patients older than 80, but a few are included in studies of younger patients. CONCLUSIONS: This case report illustrates that a patient over 80 can have a successful outcome with multidisciplinary medical coverage of medical, surgical, rehabilitative, social, and psychological areas. More studies need to be done of these patients.     

Microdecompression and uninstrumented single-level fusion for spinal canal stenosis with degenerative spondylolisthesis

STUDY DESIGN: A retrospective review was completed on 21 patients who had a "least invasive" (one or two level) microdecompression and uninstrumented single-segment lumbar fusion for spinal canal stenosis with degenerative spondylolisthesis. OBJECTIVE: To determine whether a "least invasive" approach to lumbar spinal canal stenosis and degenerative spondylolisthesis would yield acceptable results. SUMMARY OF BACKGROUND DATA: The prevailing surgical technique for symptomatic spinal canal stenosis with degenerative spondylolisthesis is a wide midline decompression and instrumented fusion. METHODS: On an average of 38 months postoperatively, 21 patients were personally assessed on four scores: 1) their overall satisfaction with the outcome of surgery, 2) an analog back and leg pain scale, 3) a functional evaluation scale, and 4) Ferguson (upshot) anterior-posterior lumbosacral and lateral flexion-extension radiographs. RESULTS: The overall satisfactory outcome on all four scales was 16 (76%) of 21. Twenty of twenty-one patients had relief of their claudicant leg pain; the overall fusion rate was 18 (86%) of 21. Two of three patients with a pseudarthrosis had a successful outcome on the patient-oriented outcome (1, 2, and 3) scales (excluding the radiograph scale), and one was a failure. One patient with a solid fusion was a failure because of continuing back pain. One patient with a solid fusion was a failure because of continuing leg pain. The overall satisfactory outcome on the nonradiographic scales was 18 of 21, for an 86% patient satisfaction rate. CONCLUSIONS: In this retrospective study, a "least invasive" surgical approach to lumbar degenerative spondylolisthesis with spinal canal stenosis causing claudicant leg pain produced acceptable results.     

The surgical treatment of low back pain

If nonoperative management fails to relieve a clearly identifiable and surgically treatable cause of lumbar pain, then surgery may be beneficial. Certain "red flags" indicate the need for urgent or emergent surgical intervention. Low back pain is associated with several degenerative conditions in the lumbar spine, including degenerative disc disease, spinal stenosis, spondylolisthesis, degenerative scoliosis, facet joint syndrome, and disc herniation.     

A prospective and consecutive study of surgically treated lumbar spinal stenosis. Part I: Clinical features related to radiographic findings

STUDY DESIGN: A prospective and consecutive study of surgical results obtained during serial follow-up investigations in patients who underwent surgery for central lumbar spinal stenosis. OBJECTIVES: To evaluate the result after surgical decompression for lumbar spinal stenosis, at regular intervals after surgery, and to correlate these results with values for preoperative parameters; special interest was focused on the results in relation to the degree of constriction of the spinal canal. SUMMARY OF BACKGROUND DATA: The outcome after surgery for spinal stenosis is debatable; long-term follow-up investigations have indicated deterioration with passing time. Results of studies in nonsurgical patients have demonstrated that the symptoms do not progress with time. Results of a meta-analysis of the literature on surgical results have demonstrated a wide variation of outcomes. MATERIAL AND METHODS: In a prospective study, 105 consecutive patients who underwent surgical decompression (laminectomy with facet-preserving technique, but no fusion) were evaluated at follow-up examinations 4 months and 1, 2, and 5 years after surgery. At the follow-up examinations, the patient's opinion on the surgical result was registered, using a four-grade scale. The occurrence of pain at rest and at night was registered, as well as the patient's walking ability. Statistical analysis was performed, relating the surgical results to patient age, gender, preoperative duration of symptoms and radiographically observed constriction as described in Part I of this study. The radiologist was blinded to patient outcome. Logistic regression analysis was performed. RESULTS: During the follow-up period, 19 patients underwent reoperation, consisting of fusion to treat lumbar pain (n = 4), repeat decompression because of progressive stenosis (n = 13), and repairs in response to surgical complications (n = 2). Follow-up results: The result, related to the recurrence of leg symptoms, deteriorated with passing time. Excellent results were reported by 63% to 67% at 4-month and 2-year follow-ups compared with 52% at the 5-year follow-up. There was a correlation between the constriction of the spinal canal and the outcome at all intervals. Patients with an anteroposterior diameter of 6 mm or less at the narrowest site had significantly better results. The logistic regression analysis demonstrated a significant correlation between a severe reduction of the anteroposterior diameter and excellent results and a tendency toward better results in patients with a shorter preoperative duration of symptoms. Improvement of walking ability was also associated with a pronounced constriction of the spinal canal. CONCLUSION: The results after surgical decompression in patients with central spinal stenosis deteriorated with time. There was a significant correlation between good result and pronounced constriction of the spinal canal. Patients with a preoperative duration of symptoms of less than 4 years and patients with no preoperative back pain tended to have better surgical outcomes. The reoperation rate was 18% within 5 years. When surgery for spinal stenosis is contemplated, these prognostic factors should be taken into consideration: The "ideal patient" has a pronounced constriction of the spinal canal, insignificant lower back pain, no concomitant disease affecting walking ability, and a symptom duration of less than 4 years.     

Lower urinary tract symptoms in lumbar root compression syndromes: a prospective survey

STUDY DESIGN: A prospective, observational survey. OBJECTIVES: To describe lower urinary tract symptoms in uncomplicated lumbar root compression syndromes with special reference to prevalence, nature, and severity, and to analyze whether the occurrence of lower urinary tract symptoms correlates with age, pain, analgesic intake, or the type and level of compression. SUMMARY OF BACKGROUND DATA: Lower urinary tract symptoms with lumbar root compression are well known in the classic but rather rare cauda equina syndrome. However, micturition difficulties seem to be far more frequent in lumbar root compression syndromes. METHODS: One hundred eight male patients admitted for surgery for lumbar disc herniation or spinal stenosis were investigated with an extensive questionnaire about their micturition. RESULTS: Fifty-five percent had significant lower urinary tract symptoms. Eighty percent of the patients with spinal stenosis had symptoms. Thirty-three patients had irritative symptoms, 36 had obstructive symptoms, and 23 had retention symptoms. Twenty-four had severe symptoms. Median compression resulted in more symptoms than paramedian compression. There was no correlation between age, level of compression, drug intake, or pain score and lower urinary tract symptoms. CONCLUSIONS: Lower urinary tract symptoms of mixed type occur with a high prevalence in male patients with lumbar root compression syndromes referred for neurosurgical evaluation and treatment.