Balloon device for experimental graded spinal cord compression in the rat

We have developed a balloon device that creates reproducible graded compression of the rat spinal cord. It uses a modified Camino intracranial pressure monitor bolt with a small latex balloon attached to the tip. The device is affixed to the spinous processes of two cervicothoracic vertebrae and positioned directly over an exposed segment of spinal cord. Ten compression balloons were tested and revealed reproducible pressure transmission at expansion volumes from 0.12 to 0.34 cc. Reversible graded spinal cord compression was verified by monitoring cortical somatosensory and motor evoked potentials before, during, and after cord compression. The pathophysiologic changes occurring with graded compression and the effect of therapeutic interventions can be studied in a rat model.

Pathology of the spinal cord damaged by ossification of the posterior longitudinal ligament associated with spinal cord injury

A 63-year-old male became quadriplegic after spinal injury associated with ossification of the posterior longitudinal ligament of the cervical spine and died 4 years later. A postmortem examination of the cervical spinal cord showed various unfavorable pathological changes accounting for severe myelopathy.

Neurological complications of neurofibromatosis type 1 in adulthood

Neurofibromatosis type 1 (NF1) is a genetic disease with a wide range of neurological manifestations. To examine these, and to evaluate neurological morbidity in adulthood of patients with NF1, we studied a hospital-based series of 158 patients that included 138 adult patients aged >18 years and 20 children. NF1 evaluation included a multidisciplinary clinical and a clinically oriented radiological investigation. Neurological events occurring during childhood (in both children and adults of the series) and adulthood were recorded. One or several neurological manifestations have been observed in 55% of patients (adults and children) (n = 87). These included: headache (28 patients); hydrocephalus (7); epilepsy (5); lacunar stroke (1); white matter disease (1); intraspinal neurofibroma (3); facial palsy (1); radiculopathy (5); and polyneuropathy (2). Tumours included: optic pathway tumours (20); meningioma (2); cerebral glioma (3); and malignant peripheral nerve sheath tumours (6). Life-threatening complications were observed in five adults and included four malignant peripheral nerve sheath tumours and one meningioma. Pain was the leading symptom in 11 adults and was related to malignant peripheral nerve sheath tumours, complications of intraspinal neurofibromas, subcutaneous neurofibromas and peripheral nerve neurofibromas. NF1 in adults was not associated with other disabling or life-threatening neurological complications. Symptomatic optic pathway tumours, cerebral gliomas, symptomatic aqueductal stenosis and spinal compression due to intraspinal NF were observed exclusively during childhood. In this series, the predominant neurological features of adults with NF1 were chronic pain and malignant peripheral nerve sheath tumours.

Successful conservative treatment of rheumatoid subaxial subluxation resulting in improvement of myelopathy, reduction of subluxation, and stabilisation of the cervical spine. A report of two cases

OBJECTIVE

To report the efficacy of conservative treatment with cervical traction and immobilisation with a Halo vest, in two consecutive rheumatoid arthritis patients with progressive cervical myelopathy caused by subaxial subluxation.

METHODS

Description of neurological symptoms and signs and findings in plain radiography (PR) and magnetic resonance imaging (MRI) of the cervical spine before and after treatment of the subaxial subluxation by traction and immobilisation with a Halo vest during four months.

RESULTS

During four months of traction and immobilisation neurological examination showed a considerable improvement of the signs and symptoms of cervical myelopathy. Afterwards PR and MRI of the cervical spine showed reduction of the subaxial subluxation. Eventually firm stabilisation was obtained in both patients without surgery of the cervical spine.

CONCLUSION

Cervical traction and immobilisation with a Halo vest can be considered as an independent conservative treatment in rheumatoid arthritis patients with cervical myelopathy caused by subaxial subluxation.

Improved recovery after spinal cord trauma in ICAM-1 and P-selectin knockout mice

Traumatic spinal cord injury is followed by infiltration of leukocytes, influenced by endothelial adhesion molecules such as ICAM-1 and P-selectin. In order to evaluate the pathogenetical role of these molecules, wild-type mice and mice lacking ICAM-1 and P-selectin were subjected to an experimental spinal cord compression of two degrees of severity. Hind limb motor function decreased after injury in all animals but the groups of injured ICAM-1/P-selectin knockout animals had a better functional outcome during the entire observation period of 14 days. This difference was statistically significant on day 1. Our results indicate that adhesion molecules influence the functional outcome after spinal cord injury in a negative way and may be a target for future therapy of neurotrauma.

Management of patients with vertebral compression fractures

Osteoporosis is a disease of low bone mass that may not manifest until a patient has a fracture. Hip fracture is the most devastating, but vertebral fracture is the most common, occurring in 25% of women over 50 years of age and 40% of those age 80-85 years. Although 60% of vertebral fractures are clinically silent, they are easily diagnosed radiographically. They are associated with height loss, deformity, impaired mobility, and pain. Patients should be evaluated for the cause of both the fracture and osteoporosis. Therapy includes education about the disease, an exercise program, and advice about tailoring routine activities. Pharmacotherapy includes annual influenza vaccines, and daily calcium (1200-1500 mg elemental calcium/day) and vitamin D (400-800 IU/day) supplements. New antiresorptive agents alendronate, hormone replacement therapy, and salmon calcitonin should be offered to all patients as they reduce fracture rates.

Metastatic spinal cord compression: diagnostic delay, treatment, and outcome

BACKGROUND

Metastatic spinal cord compression (MSCC) is a disabling complication of malignant disease. The aim of this study was to estimate diagnostic delay, treatment outcome, and prognostic factors in patients with MSCC.

MATERIAL AND METHODS

In 86 patients treated for MSCC at our institution, the median age was 65 years and there was a preponderance of males (73%). The median observation period was 39 months. Carcinoma of the prostate, lung, breast, and kidney constituted 66% of the primary malignancies. Prior to treatment, 34% had grade 1, 53% grade 2, and 13% grade 3 paresis. 33% underwent surgical laminectomy with postoperative radiotherapy (combined therapy), while 67% were irradiated only.

RESULTS

Median time from the start of symptoms to the first doctor contact was 1 day, and to hospital admission or treatment start 6 days and 8 days. The pre-treatment grade of paresis, preservation of gait function, and primary tumour histology were strong predictors for treatment response. Pain relief, reported by 82% of assessable patients, correlated to treatment response grade. Median survival from treatment start was 4.1 months. Survival corresponded positively to preserved gait function at admission, to treatment response grade, and to the employment of combined therapy. Primary tumour histology was an important predictor as breast cancer and prostate cancer had 3 to 6-fold longer survival compared to lung cancer patients.

CONCLUSION

Prolonged survival in a minority of the patients signified the importance of optimal treatment. To settle whether radiotherapy alone is the optimal treatment in all MSCC patients, a randomised trial is warranted.

Closed reduction of bilateral locked facets of the cervical spine under general anaesthesia

BACKGROUND

Bilateral facet interlocking of the cervical spine is a relatively uncommon type of cervical spinal injury. It is frequently associated with devastating neurological symptoms and signs. Early reduction of the locked facets is thought to be critical in preventing progressive secondary spinal cord injury. Whereas skull tong traction remains our primary option for closed reduction of bilateral locked facets of the cervical spine, it is not always successful, even with heavy traction weights. Other more aggressive measures may occasionally be required. The authors report their experience in reducing bilateral locked facets of the cervical spine by manual closed reduction.

METHODS

This small series consists of six cases of cervical spinal injury with bilateral locked facets in which manual closed reduction under general anaethesia and muscle relaxation was used. Three of them presented with complete quadriplegia (Frankel class A). One case presented with incomplete but severe neurological deficits (Frankel class B). After unsuccessful closed reduction with skull traction, these patients were treated by manual closed reduction under general anaesthesia and muscle relaxation, followed by anterior discectomy, interbody fusion and stabilization.

RESULTS

All cases made neurological improvement after the procedures. Even in cases with initial severe neurological deficits, the recovery was remarkable. The recovery was dramatic in two cases. Case 1 improved from Frankel class B to E; and Case 5 from Frankel class A to D. No case deteriorated neurologically after the procedures. Pneumonia occurred in Case 3; and stress ulcer accompanied by haemorrhage was noted in Case 4. None of these complications was directly related to the procedures.

CONCLUSION

The potential for improvement of neurological function following early and successful reduction and fixation of the dislocated spine is emphasized. With meticulous techniques, manual closed reduction may be an effective alternative to skull tong traction when the latter fails.

[Spinal cord injury in multiple myeloma]

Myelomic spinal cord damage may be a result of both its compression and vascular disorders (squeezing of an artery, disorders of venous outflow). Diagnosis is based on evaluation of the following signs: normochromic anemia; increase of ESR, total protein and calcium levels; discovery of M-gradient in protein fractions of gamma-zone; multiple regions of destruction in spondylogramme. In doubtful cases magneto-resonance and computer tomography were the most informative. Highly effective was therapy with intensive chemoprogramme including either a range of preparations (alkeran, BGNU, cyclophosphan, adriblastina, prednisolon) or a combination of polychemotherapy with irradiation. The operation was indicated in both insufficiency of conservative therapy and increasing of the symptoms of the damage.

[Spinal cord compression secondary to epidural extramedullary hematopoiesis in thalassemia: a clinical case and review of literature]

INTRODUCTION

Extramedullary hematopoiesis generally occurs in a variety of hematological disorders where the normal functioning of the blood forming organs is disturbed. It is a common manifestation in thalassemia where it occurs as a compensatory phenomenon in order to combat long standing anemia. Spinal cord compression as a consequence of extramedullary hematopoiesis in the intraspinal epidural space is an extremely rare complication, though this complication has been reported more commonly in thalassemia.

CLINICAL CASE

A case of spinal cord compression due to extramedullary hematopoiesis in a patient with thalassemia is reported. The patient was successfully treated with radiation therapy and blood transfusions and he made a complete clinical recovery. Development. The literature is reviewed and the efficacy of several treatments such as surgery, radiotherapy and blood transfusion therapy is discussed. Until recently surgical decompression followed by radiation therapy remained the recommended treatment. Hematopoietic tissue is particularly sensitive to the ionizing radiation and low-dose radiotherapy is enough to relieve the spinal cord compression. Blood transfusion therapy may be diagnostically and therapeutically useful in the management of this entity.

CONCLUSIONS

A prompt recognition of the syndrome and early treatment with radiotherapy and blood transfusion therapy is recommended to prevent irreversible damage to the spinal cord. Surgery may be only considered in the event of progressive neurological deficit despite of radiotherapy or blood transfusion therapy.

Trauma in congenital atlanto-axial dislocation

Congenital atlanto-axial dislocation (AAD) usually presents with chronically progressive compression of the cervico-medullary junction. However, even a minor trauma can cause acute compression with development of quadruplegia and respiratory impairment. At times these may be transient, or trauma may aggravate the compression and lead to progressive quadriplegia. Of 60 children seen with congenital AAD, in 15 it had been associated with trauma. Nine of these 15 AADs were of the mobile variety, and 6 of the fixed variety with odontoid invagination. In 6 children with mobile and 2 with fixed AAD, trauma led to an acute manifestation with quadriplegia. Three of the children also experienced respiratory distress and needed ventilatory support. All 15 were initially treated with skull traction. Once the condition was stabilised, those with the mobile variety underwent fixation in a reduced position and grafting. One of the children with respiratory distress died within 2 days of admission. In 4 of them, sublaminar wiring between C1 and C2 was carried out, and in 3 others wiring between occiput and base of spinous process of C2 was performed. In 1 case a Hartshill loop was used. Among the children with fixed AAD, reduction of the odontoid invagination was obtained in 2, and they underwent fusion. In 4 cases with unsatisfactory reduction, posterior decompression of the foramen magnum and the fused posterior arch of the atlas was performed. The results depended on the degree of neurological deficit in each child.

Effect of hypertonic saline on leukocyte activity after spinal cord injury

STUDY DESIGN

The effect of intravenous administration of hypertonic saline on leukocyte adhesion after compression injury of the spinal cord was evaluated.

OBJECTIVES

To investigate changes in leukocyte adhesion after spinal cord injury and to evaluate the effect of hypertonic saline on this process.

SUMMARY OF BACKGROUND DATA

Leukocytes have been thought to exacerbate tissue injury after ischemia-reperfusion. Downregulating and reducing the number of circulating leukocytes has attenuated tissue damage in various models of cerebral ischemia. Recently, investigators have reported that leukocytes exacerbate injury in the spinal cord after trauma. Other recent findings have indicated that hypertonic saline may play a role in decreasing leukocyte adhesion and activation.

METHODS

Sprague-Dawley rats were anesthetized, and a C3-C5 laminectomy was performed. Injury was caused by 35 g of compression applied to the cord for 10 minutes. Animals were divided into three groups: sham treated, untreated, and treated. The treated animals received 7.5% hypertonic saline (5 mL/kg, intravenously) 5 minutes after the injury. Sticking leukocytes and shear rate were measured using fluorescence microscopy.

RESULTS

Administration of 7.5% hypertonic saline after injury significantly decreased the number of sticking leukocytes in the venules and arterioles. Shear rate was unchanged between the groups.

CONCLUSIONS

The results show that an increase in leukocyte adhesion after a compressive injury is attenuated by the administration of 7.5% hypertonic saline. The decrease in adhesion cannot be attributed to changes in the shearing forces, because no significant change was observed in the shear rate. Hypertonic saline may interfere with leukocytes directly by interfering with their ability to swell and thus may prevent activation.

Cervical spinal cord compression caused by cryptococcosis in a dog: successful treatment with surgery and fluconazole

A six-year-old, male Doberman pinscher was presented for acute onset of upper motor neuron tetraparesis. An extradural compressive lesion compatible with intervertebral disk rupture at the sixth to seventh cervical (C6-C7) disk space was evident on myelography. A large, gelatinous mass of pure cryptococcal organisms causing spinal cord compression was identified upon exploratory surgery. Removal of the mass caused relief of clinical signs. No evidence of involvement of other organ systems was found; however, serum and cerebrospinal fluid titers were positive for cryptococcal infection. The dog was treated with fluconazole (5.5 mg/kg body weight, per os sid) until serum titers for cryptococcal infection were negative at seven months postsurgery. To the authors' knowledge, this is the only report of a dog with cryptococcosis treated successfully using fluconazole as a sole agent.

Systemic hypothermia after spinal cord compression injury in the rat: does recorded temperature in accessible organs reflect the intramedullary temperature in the spinal cord?

This article addresses one basic issue regarding the use of systemic hypothermia in the acute management of spinal cord injury, namely, how to interpret temperature recordings in accessible organs such as the rectum or esophagus with reference to the spinal cord temperature. Thirty-six rats, divided into six groups, were randomized to laminectomy or to severe spinal cord compression trauma, and were further randomized to either a cooling/rewarming procedure or continuous normothermia (esophageal temperature 38 degrees C) for 90 min. The first procedure comprised normothermia during the surgical procedure, followed by lowering of the esophageal temperature from 38 degrees C to 30 degrees C (the hypothermic level), a 20-min steady-state period at 30 degrees C, rewarming to 38 degrees C, and finally a 20-min steady-state period at 38 degrees C. The esophageal, rectal, and epidural temperatures were recorded in all animals. The intramedullary temperature was also recorded invasively in four of the six groups. We conclude that the esophageal temperature is safe and easy to record and, in our setting, reflects the epidural temperature. The differences registrated may reflect a true deviation of the intramedullary temperature due to initial environmental exposure and secondary injury processes. Our results indicate that the esophageal temperature exceeds the intramedullary temperature during the initial recording and final steady state following rewarming, but not during the most crucial part of the experiment, the hypothermic period. The core temperature measured in the esophagus can therefore be used to evaluate the intramedullary temperature during alterations of the systemic temperature and during hypothermic periods.

Percutaneous access to the anterior spinal canal through a cervical disk

We describe a CT-guided percutaneous technique for aspiration of an anterior intraspinal fluid collection through a cervical disk. The approach is identical to that of cervical diskography or percutaneous cervical diskectomy, with intentional placement of the needle tip in the spinal canal. This procedure had no adverse effects and avoided an open operation to exclude spinal cord compression.

The therapeutic impact of lumbar spine MRI on patients with low back and leg pain

The influence of lumbar spine magnetic resonance imaging (MRI) on the management of patients with low back and leg pain, with a clinical diagnosis of neural compression, has been investigated by a controlled prospective observational study. The clinical features of the patients at the time of request for MRI have been compared with the subsequent management in order to define the clinical indications for lumbar spine MRI.

METHODS

Clinical history, physical examination findings and tests of functional and psychological disability were all recorded at the time of request for MRI. Following MRI, patients were assessed without knowledge of the MRI findings and a diagnosis and management plan recorded. Immediate access to the MRI report and hard copy films was then provided and a revised diagnosis and management plan made. The clinical features and MRI findings were compared with the subsequent management.

RESULTS

Seventy-two patients were examined, 65 (90.3%) had leg pain as a predominant feature and abnormalities in neurological examination were found in 31 (43%). Twenty-three of 48 (47.9%) of patients with a pre MRI management plan of surgery were changed to conservative management following the MRI. The diagnosis altered in 50 % of cases with the largest change in diagnosis occurring in 13 patients where MRI did not confirm the clinical impression of nerve root compression. Seventeen patients with no abnormality of neurological testing were subsequently treated by surgery which included all 12 patients treated by spinal fusion.

CONCLUSIONS

The major impact of MRI was to move patients towards conservative treatment. A variety of features in the history and physical examination as well as MRI findings are predictors for surgical treatment. The variety of diagnoses and surgical options available make it difficult to define clear clinical guidelines for the use of MRI.

Malignant spinal cord compression: prospective study of delays in referral and treatment

OBJECTIVES

To examine the delay in presentation, diagnosis, and treatment of malignant spinal cord compression and to define the effect of this delay on motor and bladder function at the time of treatment.

DESIGN

Prospective study of all new patients presenting to a regional cancer centre with this condition.

SETTING

Regional cancer centre.

SUBJECTS

301 consecutive patients.

MAIN OUTCOME MEASURES

Interval from onset of symptoms to presentation and treatment, delay at each stage of referral, and functional deterioration.

RESULTS

The median (range) delay from onset of symptoms of spinal cord compression to treatment was 14 (0-840) days. Of the total delay, 3 (0-300) days were accounted for by patients, 3 (0-330) days by general practitioners, 4 (0-794) days by the district general hospital, and 0 (0-114) days by the treatment unit. Initial presentation to the regional cancer centre with symptoms of malignant spinal cord compression led to a significant reduction in delay to treatment and improved functional status at the time of treatment. Deterioration of motor or bladder function >=1 grade occurred at the general practice stage in 28% (57) and 18% (36) of patients, the general hospital stage in 36% (83) and 29% (66), and the treatment unit stage in 6% (19) and 5% (15), respectively.

CONCLUSIONS

Unacceptable delay in diagnosis, investigation, and referral occurs in most patients with malignant spinal cord compression and results in preventable loss of function before treatment. Improvement in the outcome of such patients requires earlier diagnosis and treatment.

Neurologic emergencies in cancer patients

Neurologic emergencies are common among cancer patients and their incidence is increasing as patients live longer as a result of improved antineoplastic therapy. This article reviews acute neurologic complications in cancer patients. Among those complications reviewed are brain metastases, epidural spinal cord compression, leptomeningeal metastases, cerebrovascular disorders, complications of antineoplastic therapy, and paraneoplastic syndromes.

Reversal of renal failure and paraplegia after thoracoabdominal aneurysm repair

Repair of ruptured thoracoabdominal aortic aneurysms is complicated by high rates of perioperative paraplegia, renal insufficiency, and mortality. This report describes a patient with a ruptured thoracoabdominal aortic aneurysm in whom preoperative acute renal failure was reversed with hemodialysis, aortic replacement, and renal revascularization. Prompt cerebrospinal fluid drainage reversed delayed-onset postoperative paraplegia and led to immediate, complete neurologic recovery.