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Biomedical subjects

N Bogduk

Publications and source records attributed to N Bogduk.

At least 37 records · Page 2Linked to original sources
PubMed1999

The ligaments and annulus fibrosus of human adult cervical intervertebral discs.

STUDY DESIGN: Descriptive, microdissection study. OBJECTIVE: To determine the morphology of the human adult cervical intervertebral disc and its ligaments. SUMMARY OF BACKGROUND DATA: Some studies indicate that the cervical disc is distinctly different from the lumbar intervertebral disc, yet most clinical and anatomic texts appear content with extrapolating data from the lumbar spine. A detailed three-dimensional description of the cervical intervertebral disc and its surrounding ligaments is currently unavailable. METHODS: Whole cervical spinal columns were freed from 12 human adult embalmed cadavers, and the posterior elements and soft tissues were removed. Using microdissection, the longitudinal ligaments and the fibrous components of 59 cervical intervertebral disc were resected systematically. The orientation, location, and attachments of each stripped bundle of collagen were recorded photographically and in sketches. RESULTS: The cervical anulus fibrosus does not consist of concentric laminae of collagen fibers as in lumbar discs. Instead, it forms a crescentic mass of collagen thick anteriorly and tapering laterally toward the uncinate processes. It is essentially deficient posterolaterally and is represented posteriorly only by a thin layer of paramedian, vertically orientated fibers. The anterior longitudinal ligament covers the front of the disc, and the posterior longitudinal ligament reinforces the deficient posterior anulus fibrosus with longitudinal and alar fibers. CONCLUSIONS: The three-dimensional architecture of the cervical anulus fibrosus is more like a crescentic anterior interosseous ligament than a ring of fibers surrounding the nucleus pulposus.

Adult↗
PubMed1999

Regional musculoskeletal pain. The neck.

Tumours, infections, aneurysms and metabolic and inflammatory diseases are rare causes of neck pain. Most cases involve neck pain of unknown origin or a whiplash-associated disorder. Neck pain is common in the general community and more common in certain occupations. The natural history is relatively benign, but some 10% of patients will suffer chronic, severe symptoms. Psychosocial factors have been refuted as risk factors; the cardinal risk factors relate to occupation. In whiplash, the severity of initial symptoms is the cardinal determinant of chronicity. History is the major factor when considering diagnosis, physical examination adding little to the diagnosis. Imaging is not indicated in the vast majority of cases. The available evidence does not support most of the physical, medical and surgical therapies currently practised. Confident reassurance is paramount and justified for acute cases. Proven options for chronic neck pain are few.

Humans↗
PubMed1999

Long-term follow-up of patients treated with cervical radiofrequency neurotomy for chronic neck pain.

OBJECTIVE: To determine the long-term efficacy of percutaneous radiofrequency medial branch neurotomy in the treatment of chronic neck pain. METHODS: Between 1991 and 1996, radiofrequency neurotomy was performed in 28 patients diagnosed as having cervical zygapophysial joint pain on the basis of controlled diagnostic blocks. The procedure was repeated in patients whose pain recurred. Outcome measures were the proportion of patients who responded to the initial procedure and the duration of relief subsequently obtained. Outcome was correlated with the operator performing the procedure, the type of electrode used, litigation status, and the type of diagnostic blocks used to establish the diagnosis. RESULTS: Complete relief of pain was obtained in 71% of patients after an initial procedure. No patient who failed to respond to a first procedure responded to a repeat procedure, but if pain returned after a successful initial procedure, relief could be reinstated by a repeat procedure. The median duration of relief after a first procedure was 219 days when failures are included but 422 days when only successful cases are considered. The median duration of relief after repeat procedures was at least 219 days; several patients had ongoing relief at the time of follow-up. Outcome did not differ according to the operator, the type of electrode used, litigation status, or the type of diagnostic block used. CONCLUSION: Radiofrequency neurotomy provides clinically significant and satisfying periods of freedom from pain, and its effects can be reinstated if pain recurs.

Adult↗
PubMed1999

The neck

Tumours, infections, aneurysms and metabolic and inflammatory diseases are rare causes of neck pain. Most cases involve neck pain of unknown origin or a whiplash-associated disorder. Neck pain is common in the general community and more common in certain occupations. The natural history is relatively benign, but some 10% of patients will suffer chronic, severe symptoms. Psychosocial factors have been refuted as risk factors; the cardinal risk factors relate to occupation. In whiplash, the severity of initial symptoms is the cardinal determinant of chronicity. History is the major factor when considering diagnosis, physical examination adding little to the diagnosis. Imaging is not indicated in the vast majority of cases. The available evidence does not support most of the physical, medical and surgical therapies currently practised. Confident reassurance is paramount and justified for acute cases. Proven options for chronic neck pain are few.

Journal Article↗
PubMed1998

The ability of lumbar medial branch blocks to anesthetize the zygapophysial joint. A physiologic challenge.

STUDY DESIGN: Randomized, controlled, single blinded study. OBJECTIVES: To determine the physiologic effectiveness of lumbar medial branch blocks. SUMMARY OF BACKGROUND DATA: Zygapophysial joint pain can be diagnosed by anesthetization of the joint or its nerve supply (the medial branch divisions of the dorsal rami). The physiologic effectiveness of lumbar medial branch blocks has been assumed but not proven. METHODS: Eighteen asymptomatic individuals were randomly assigned to either L4-L5 or L5-S1 zygapophysial joint injections with contrast medium until capsular distention elicited pain without extracapsular contrast spread. One week later, 15 blinded individuals underwent two randomized saline or 2% lidocaine medial branch injections that correlated to the innervation of the previously injected joint. Medical branch injections were performed such that inadvertent venous uptake was avoided in 14 individuals. Thirty minutes after medial branch injections, these 14 individuals underwent repeat capsular distention of the same zygapophysial joint provoked the prior week in an attempt to elicit another painful response. RESULTS: All five control individuals who received saline medial branch injections felt pain on repeat capsular distention. Nine individuals received 2% lidocaine medial branch blocks; eight felt no pain, and one felt pain on repeat capsular distention. CONCLUSIONS: There was a significant effect of 2% lidocaine (versus saline) medial branch injections on anesthetization of the zygapophysial joint when venous uptake was avoided during these injections. When properly performed, lumbar medial branch blocks successfully inhibit pain associated with capsular distention of the lumbar zygapophysial joints at a rate of 89%.

Adult↗
PubMed1998

The psychological profiles of patients with whiplash-associated headache.

Headache often compounds chronic neck pain following whiplash injury. To better understand post-traumatic headache, the SCL-90-R symptom checklist was used to determine the psychological profiles of patients with whiplash-associated headache and of patients with whiplash-associated neck pain without headache. The psychological profiles of these patients were compared with previously published SCL-90-R profiles of patients with post-traumatic and nontraumatic headache, and of the normal population. Patients with whiplash-associated headache were not significantly different from those with other forms of post-traumatic headache or with whiplash-associated neck pain without headache. However, when patients with whiplash-associated headache and patients with nontraumatic headache were compared to normal data, significant differences emerged. Patients with nontraumatic headache exhibited higher scores on all subscales, whereas patients with whiplash-associated headache differed from the normal sample only on somatization, obsessive-compulsive, depression and hostility subscales, and the global severity index. These differences imply that patients with whiplash-associated headache suffer psychological distress secondary to chronic pain and not from tension headache and generalized psychological distress.

Case-Control Studies↗
PubMed1998

Cervical spine disorders.

Recent research of disorders of the neck has concentrated on the efficacy of manual and other conservative therapies for neck pain and whiplash. Systematic reviews paint a poor picture of the quality of literature upon which many conventional, conservative therapies are based. Conclusive scientific data are lacking. Despite its unsavory reputation, whiplash has attracted considerable scientific inquiry. Multiple studies have brought data to bear that indicate that chronic neck pain after whiplash is not psychogenic, and that psychologic distress is secondary to the pain. Strong studies have shown that cervical zygapophysial joint pain is the most common basis for chronic neck pain after whiplash but that this condition cannot be diagnosed other than by using controlled diagnostic blocks. Surgical treatment of cervical zygapophysial joint pain has been proven to be effective in a double-blind controlled trial.

Humans↗
PubMed1997

The pathologic effects of intrathecal betamethasone.

STUDY DESIGN: The histopathologic effects of the intrathecal injection of betamethasone (Celestone Chronodose; Schering Corporation, Kenilworth, New Jersey) were assessed after the injection of various volumes of the preparation in 20 sheep. OBJECTIVE: To assess the safety of Celestone Chronodose injected into the intrathecal space. SUMMARY OF BACKGROUND DATA: The safety and efficacy of epidural steroid have received considerable attention in the medical literature in recent years. In Australia, reports of possible adverse effects of Depo-Medrol (methylprednisolone), including the complication of arachnoiditis, have been followed by statements from the manufacturers of commonly used steroid preparations recommending they should not be administered epidurally. Previous evidence suggests that arachnoiditis does not result from epidural administration of steroids, but may develop from the intrathecal administration of Depo-Medrol. There are no reports concerning the safety of Celestone Chronodose (beta-methasone). METHODS: Twenty-three adult merino sheep had lumbar punctures performed at the L6-S1 level, and different volumes of Celestone Chronodose or normal saline were injected into the subarachnoid space. The animals were killed after 6 weeks, and the spinal cord, meninges, and nerve roots of the lumbar spine were examined for evidence of pathologic changes. RESULTS: There were no abnormalities demonstrated in three sheep injected with up to 18 ml of normal saline solution. Eleven sheep injected with 1 ml (5.7 mg) of Celestone Chronodose even when repeated at weekly intervals (five sheep, three injections) did not demonstrate pathologic changes. One of six sheep injected with 2 ml of Celestone Chronodose and all of three sheep injected with greater volumes showed histopathologic changes of arachnoiditis. CONCLUSIONS: Given that the volume of cerebrospinal fluid in the sheep is approximately one third of that in humans, this study suggests that small volumes (up to 2 ml) of Celestone Chronodose injected intrathecally in humans are unlikely to cause arachnoiditis, but that the risk of this complication increases substantially with higher doses.

Animals↗
PubMed1997

Specificity of lumbar medial branch and L5 dorsal ramus blocks. A computed tomography study.

STUDY DESIGN: A cross-sectional study. OBJECTIVES: To determine the face validity of lumbar medial branch blocks. SUMMARY OF BACKGROUND DATA: Lumbar medial branch blocks have been used increasingly to diagnose zygapophysial joint pain. The course and relations of the medial branches of the dorsal rami have been demonstrated in previous anatomic studies. What is not known is whether blocks of the medial branches anesthetize these nerves exclusively or whether they anesthetize other structures that are potential sources of pain. METHODS: In a cadaveric study, the branches of the dorsal rami were exposed. Spinal needles were placed over the nerves, and plain radiographs were taken to demonstrate the precise radiographic locations of the nerves. In the second phase of the study, healthy volunteers underwent injections of radiographic contrast over the nerves, and plain radiographs and computed tomographic images were taken. Injections were performed using different rates of injection and in two positions for each nerve. RESULTS: Radiographic contrast incorporated the medial branches of the dorsal rami in every injection. When injections were performed using the upper position, aberrant flow of contrast medium was demonstrated with extension into the epidural space or intervertebral foramina. When a position lower on the transverse process was selected, aberrant flow was very uncommon. Eight percent of injections were found to be intravenous. CONCLUSIONS: When the appropriate technique is used, medial branch blocks are target specific. To guard against false-negative responses due to intravenous up-take, contrast medium must be used before the injection of local anaesthetic.

Adult↗
PubMed1997

Resolution of psychological distress of whiplash patients following treatment by radiofrequency neurotomy: a randomised, double-blind, placebo-controlled trial.

It is well recognised that patients with chronic pain, in particular, chronic whiplash-associated neck pain, exhibit psychological distress. However, debate continues as to whether the psychological distress precedes and causes the chronic pain or, conversely, the psychological distress is a consequence of chronic pain. Using cervical zygapophysial joint pain as a model for chronic pain, the effect of a definitive neurosurgical treatment on the associated psychological distress was studied. Seventeen patients with a single painful cervical zygapophysial joint participated in a randomised, double-blind, placebo-controlled trial of percutaneous radiofrequency neurotomy. Their pain and psychological status were evaluated pre-operatively and 3 months post-operatively by medical interview and examination, a visual analogue pain scale, the McGill Pain Questionnaire, and the SCL-90-R psychological questionnaire. All patients who obtained complete pain relief exhibited resolution of their pre-operative psychological distress. In contrast, all but one of the patients whose pain remained unrelieved continued to suffer psychological distress. Because psychological distress resolved following a neurosurgical treatment which completely relieved pain, without psychological co-therapy, it is concluded that the psychological distress exhibited by these patients was a consequence of the chronic somatic pain.

Adult↗
PubMed1997

The College as an educational institution.

This is an edited transcript of a plenary lecture delivered at the Annual Scientific Meeting of the Royal Australasian College of Surgeons in May 1996. The author argues that undergraduate curricula in Australia have evolved away from exposing students to rigorous surgical basic sciences. In order to fill the gap left between undergraduate teaching and the Part I examinations, he argues that the College should become an educational institution by developing objectives and providing resources that enable candidates to learn not only what is pertinent to surgical basic training but also how to learn it and why. The call is for the College to take a leading role in education of surgical trainees.

Australia↗