Tor Ingebrigtsen

Randomized clinical trial of lumbar instrumented fusion and cognitive intervention and exercises in patients with chronic low back pain and disc degeneration.

Study Design. Single blind randomized study. Objectives. To compare the effectiveness of lumbar instrumented fusion with cognitive intervention and exercises in patients with chronic low back pain and disc degeneration. Summary of Background Data. To the authors’ best knowledge, only one randomized study has evaluated the effectiveness of lumbar fusion. The Swedish Lumbar Spine Study reported that lumbar fusion was better than continuing physiotherapy and care by the family physician. Patients and Methods. Sixty-four patients aged 25–60 years with low back pain lasting longer than 1 year and evidence of disc degeneration at L4–L5 and/or L5–S1 at radiographic examination were randomized to either lumbar fusion with posterior transpedicular screws and postoperative physiotherapy, or cognitive intervention and exercises. The cognitive intervention consisted of a lecture to give the patient an understanding that ordinary physical activity would not harm the disc and a recommendation to use the back and bend it. This was reinforced by three daily physical exercise sessions for 3 weeks. The main outcome measure was the Oswestry Disability Index. Results. At the 1-year follow-up visit, 97% of the patients, including 6 patients who had either not attended treatment or changed groups, were examined. The Oswestry Disability Index was significantly reduced from 41 to 26 after surgery, compared with 42 to 30 after cognitive intervention and exercises. The mean difference between groups was 2.3 (−6.7 to 11.4) (P = 0.33). Improvements inback pain, use of analgesics, emotional distress, life satisfaction, and return to work were not different. Fear-avoidance beliefs and fingertip-floor distance were reduced more after nonoperative treatment, and lower limb pain was reduced more after surgery. The success rateaccording to an independent observer was 70% after surgery and 76% after cognitive intervention and exercises. The early complication rate in the surgical group was 18%. Conclusion. The main outcome measure showed equal improvement in patients with chronic low back pain and disc degeneration randomized to cognitive intervention and exercises, or lumbar fusion.

Lumbar instrumented fusion compared with cognitive intervention and exercises in patients with chronic back pain after previous surgery for disc herniation: a prospective randomized controlled study.

Abstract The effectiveness of lumbar fusion for chronic low back pain after surgery for disc herniation has not been evaluated in a randomized controlled trial. The aim of the present study was to compare the effectiveness of lumbar fusion with posterior transpedicular screws and cognitive intervention and exercises. Sixty patients aged 25–60 years with low back pain lasting longer than 1 year after previous surgery for disc herniation were randomly allocated to the two treatment groups. Experienced back surgeons performed transpedicular fusion. Cognitive intervention consisted of a lecture intended to give the patient an understanding that ordinary physical activity would not harm the disc and a recommendation to use the back and bend it. This was reinforced by three daily physical exercise sessions for 3 weeks. The primary outcome measure was the Oswestry Disability Index (ODI). Outcome data were analyzed on an intention‐to‐treat basis. Ninety‐seven percent of the patients, including seven of eight patients who had either not attended treatment (n = 5) or changed groups (n = 2), completed 1‐year follow‐up. ODI was significantly improved from 47 to 38 after fusion and from 45 to 32 after cognitive intervention and exercises. The mean difference between treatments after adjustment for gender was −7.3 (95% CI −17.3 to 2.7, p = 0.15). The success rate was 50% in the fusion group and 48% in the cognitive intervention/exercise group. For patients with chronic low back pain after previous surgery for disc herniation, lumbar fusion failed to show any benefit over cognitive intervention and exercises.

Prophylactic hyperdynamic postoperative fluid therapy after aneurysmal subarachnoid hemorrhage: a clinical, prospective, randomized, controlled study.

OBJECTIVETo investigate the role of prophylactic hyperdynamic postoperative fluid therapy in preventing delayed ischemic neurological deficits attributable to cerebral vasospasm. METHODSWe designed a prospected, randomized, controlled study and included 32 patients with subarachnoid hemorrhage. Sixteen patients received hypervolemic hypertensive hemodilution fluid therapy; the other 16 patients received normovolemic fluid therapy. All patients were monitored for at least 12 days, with clinical assessments, transcranial Doppler recordings, single-photon emission computed tomographic (SPECT) scanning, and routine computed tomographic scanning. For fluid balance monitoring, a number of blood samples were obtained on a daily basis and continuous central venous pressure and mean arterial blood pressure measurements were performed for both groups. All patients received intravenous nimodipine infusions between Day 1 and Day 12. End points of this study were clinical outcomes, clinically evident and transcranial Doppler sonography-evident vasospasm, SPECT findings, complications, and costs. Clinical examinations (using the Glasgow Outcome Scale) performed 1 year after discharge, together with neuropsychological assessments and SPECT scanning, were the basis for the evaluation of clinical outcomes. RESULTSNo differences were observed between the two groups with respect to cerebral vasospasm (as observed clinically or on transcranial Doppler recordings). When regional cerebral blood flow was evaluated by means of SPECT analysis performed on Day 12 after subarachnoid hemorrhage, no differences were revealed. One-year clinical follow-up assessments (with the Glasgow Outcome Scale), including SPECT findings and neuropsychological function results, did not demonstrate any significant group differences. Costs were higher and complications were more frequent for the hyperdynamic therapy group. CONCLUSIONNeither early nor late outcome measures revealed any significant differences between the two subarachnoid hemorrhage treatment models.

Traumatic brain damage in minor head injury: relation of serum S-100 protein measurements to magnetic resonance imaging and neurobehavioral outcome.

OBJECTIVE The present study was conducted to validate S-100 protein as a marker of brain damage after minor head injury. METHODS We studied 50 patients with minor head injuries and Glasgow Coma Scale scores of 13 to 15 in whom computed tomographic scans of the brain revealed no abnormalities. Serum levels of S-100 protein were measured at admittance and hourly thereafter until 12 hours after injury. Magnetic resonance imaging and baseline neuropsychological examinations were performed within 48 hours, and neuropsychological follow-up was conducted at 3 months postinjury. RESULTS Fourteen patients (28%) had detectable serum levels of S-100 protein (mean peak value, 0.4 microg/L [standard deviation, +/- 0.3]). The S-100 protein levels were highest immediately after the trauma, and they declined each hour thereafter. At 6 hours postinjury, the serum level was below the detection limit (0.2 microg/L) in five (36%) of the patients with initially detectable levels. Magnetic resonance imaging revealed brain contusions in five patients, four of whom demonstrated detectable levels of S-100 protein in serum. The proportion of patients with detectable serum levels was significantly higher when magnetic resonance imaging revealed a brain contusion. In patients with detectable serum levels, we observed a trend toward impaired neuropsychological functioning on measures of attention, memory, and information processing speed. CONCLUSION Determination of S-100 protein levels in serum provides a valid measure of the presence and severity of traumatic brain damage if performed within the first hours after minor head injury.

Scandinavian Guidelines for Initial Management of Minimal, Mild, and Moderate Head Injuries

BACKGROUND The Scandinavian Neurotrauma Committee was initiated by the Scandinavian Neurosurgical Society to develop evidence-based guidelines for improved care of neurotrauma patients. METHODS A MEDLINE search identified 475 papers dealing with the management of minimal, mild, and moderate head injuries. Forty-two studies presenting class II evidence on the initial management of such injuries were reviewed and management guidelines were developed. RESULTS Implementation of the Head Injury Severity Scale is advocated. Patients with minimal injuries (no loss of consciousness, Glasgow Coma Scale score of 15) can be safely discharged. Routine early computed tomographic scan is recommended in cases with mild injuries (history of loss of consciousness, Glasgow Coma Scale score = 14-15) and patients with normal scans may be discharged. Computed tomographic scan and admission is mandatory in moderate injuries (Glasgow Coma Scale score = 13). All patients harboring additional risk factors should be scanned and admitted. A flow-chart for clinical decision making and a Head Injury Instruction card is introduced. CONCLUSIONS The Scandinavian Neurotrauma Committee suggests guidelines that should be safe and cost-effective for the initial management of minimal, mild, and moderate head injuries.

Traumatic Brain Damage: Serum S-100 Protein Measurements Related to Neuroradiological Findings

This study was designed to investigate the correlation between S-100 protein serum measurements and neuroradiological findings in patients with head injury. We studied 278 patients with minor, moderate, and severe head injuries and 110 controls with no history of neurological disease. The study recruited patients from three Scandinavian neurotrauma centers. Serum levels of S-100 protein were measured at admittance, and computed tomographic scans of the brain were obtained within 24 h postinjury in all patients. In a subgroup of 45 patients with minor head injuries, magnetic resonance imaging was also performed. Increased serum level of S-100 protein was detected in 108 (39%) patients, and CT scan demonstrated intracranial pathology in 25 (9%) (brain contusion n = 13, subdural hematoma n = 6, epidural hematoma n = 2, traumatic subarachnoid hemorrhage n = 2, and brain edema n = 2). The proportion of patients with detectable serum level was significantly (p < 0.01) higher among those with intracranial pathology (92%) compared to those without (34%). The negative predictive value of an undetectable S-100 serum level was 0.99. Undetectable serum level of S-100 protein predicts normal intracranial findings on CT scan. Determination of S-100 protein in serum may be used to select patients for CT scanning.

Quantification of post-concussion symptoms 3 months after minor head injury in 100 consecutive patients

Abstract Post-concussion symptoms (PCS) (such as headaches, irritability, anxiety, dizziness, fatigue and impaired concentration) are frequently experienced by patients who have sustained a minor head injury (MHI). The post-concussion syndrome has been defined as a clinical state where 3 or more symptoms persist for more than 3 months. This report focuses on the quantification of PCS according to the Rivermead Postconcussion Symptoms Questionnaire (RPQ). We studied 100 consecutive patients with MHI and normal computed tomography of the brain. At 3 months after injury, 62% reported the presence of one or more symptoms, and 40% fulfilled the diagnostic criteria for post-concussion syndrome. Patients with post-concussion syndrome had significantly (P < 0.001) higher RPQ scores (mean 19.1, SD 11.9) than those without (mean 1.2, SD 1.8). Patients on sick leave owing to the injury reported significantly (P = 0.05) higher RPQ scores (mean 10.3, SD 13.2) than those not on sick leave (mean 5.5, SD 8.6). We observed no association between age, gender, cause of injury, severity of injury, duration of amnesia and RPQ score. RPQ score provides useful information about the severity of PCS regardless of whether the diagnostic criteria for the post-concussion syndrome are met or not.

Increased serum concentrations of protein S-100 after minor head injury: a biochemical serum marker with prognostic value?

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Determination of Wall Tension in Cerebral Artery Aneurysms by Numerical Simulation

Background and Purpose— Cerebral artery aneurysms rupture when wall tension exceeds the strength of the wall tissue. At present, risk-assessment of unruptured aneurysms does not include evaluation of the lesions shape, yet clinical experience suggests that this is of importance. We aimed to develop a computational model for simulation of fluid-structure interaction in cerebral aneurysms based on patient specific lesion geometry, with special emphasis on wall tension. Methods— An advanced isogeometric fluid-structure analysis model incorporating flexible aneurysm wall based on patient specific computed tomography angiogram images was developed. Variables used in the simulation model were retrieved from a literature review. Results— The simulation results exposed areas of high wall tension and wall displacement located where aneurysms usually rupture. Conclusion— We suggest that analyzing wall tension and wall displacement in cerebral aneurysms by numeric simulation could be developed into a novel method for individualized prediction of rupture risk.

Computation of Hemodynamics in the Circle of Willis

Background and Purpose— Wall shear stress (WSS) and pressure are important factors in the development of cerebral aneurysms. We aimed to develop a computational fluid dynamics simulator for flow in the complete circle of Willis to study the impact of variations in vessel radii and bifurcation angles on WSS and pressure on vessel walls. Methods— Blood flow was modeled with Navier-Stokes equations as an incompressible newtonian fluid within rigid vessel walls. A model of the circle of Willis geometry was approximated as a network of tubes around cubic curves. Pulsatile inlet flow rates and constant outlet pressure were used as boundary conditions. Results— The simulations confirmed that differences in vessel radii and asymmetric branch angles influence WSS magnitude and spatial distribution. High WSS occurred at locations where aneurysms are frequent and in anatomic variants known to be associated with an increased risk for aneurysm development. Conclusions— Computational fluid dynamics analysis can be applied to the complete circle of Willis and should be used to study the pathophysiology of this complex vascular structure, including risk factors for aneurysm development. Further development of the method should include simulations with flexible vessel walls.