Resources for preventing sickness absence due to low back pain.

BACKGROUND: After an episode of non-specific low back pain (LBP) some individuals fail to return to work. The factors leading to such LBP-related sickness absence are not yet fully understood. AIMS: To identify individual resources, over and above the already established predictors, for preventing LBP-related sickness absence in a population-based sample of workers experiencing an episode of LBP. METHODS: Cohort study with 1-year follow-up. Participants were from a working population who reported an episode of acute or subacute LBP at baseline. Four potential resources-life satisfaction, doing sports, job satisfaction and social support at work-were examined for their incremental value in predicting sickness absence over and above baseline sickness absence and fear-avoidance beliefs about work. RESULTS: In all, 279 workers participated in the study. All four resources showed an inverse relationship with regard to sickness absence. A multiple regression analysis revealed that life satisfaction as a resource protected against sickness absence, when controlling for established risk factors. Job satisfaction and social support at work minimized the influence of sickness absence at baseline and at 1-year follow-up. CONCLUSIONS: In a non-clinical working sample of individuals experiencing an acute/subacute episode of LBP, life satisfaction was a unique predictor of sickness absence after 1 year. Prevention in the occupational setting should not only address common risk factors but also occupational and individual resources that keep workers satisfied with life despite having LBP.

Age-related changes in human cervical, thoracal and lumbar intervertebral disc exhibit a strong intra-individual correlation.

INTRODUCTION: Intervertebral disc (IVD) degeneration is characterized as a multifactorial disease, in which the hereditary background is thought to be of high importance. Accordingly, one would expect all spinal levels (lumbar/cervical/thoracal) to be affected by above-average disc degeneration in genetically predisposed individuals. The aim of this study, therefore, was to analyze the amount of degenerative changes in different spine levels in humans from different ages. MATERIALS AND METHODS: In detail, the presence, localization and abundance of histomorphological changes in the annulus fibrosus (AF) and nucleus pulposus (NP) in the cervical (C5/C6), thoracic (T2/T3) and lumbar (L2/L3) spine were investigated in complete autopsy IVD specimens (47 individuals) covering a complete age range (0-95 years). RESULTS: Results indicate that the highest degree of histo-degenerative changes were observed in the NP in all spine levels and showed an age-related expression pattern. With regard to the different spine levels, lumbar disc specimen showed significantly more degenerative changes compared to cervical and thoracic discs, whereas no statistical difference was observed between cervical and thoracic discs. In summary, highest grades of degeneration were observed in lumbar discs (especially in the NP). Intra-individual correlations between the degeneration score in the different levels showed a significant individual concordance. CONCLUSIONS: The intra-individual correlation of degenerative changes in all three examined spine regions further supports the notion that individual, i.e. genetic factors are strong predisposing factor for the development of age-related disc alterations.

Triptolide exhibits anti-inflammatory, anti-catabolic as well as anabolic effects and suppresses TLR expression and MAPK activity in IL-1ß treated human intervertebral disc cells.

INTRODUCTION: Increased levels of proinflammatory cytokines seem to play a pivotal role in the development of back pain in a subpopulation of patients with degenerative intervertebral disc (IVD) disease. As current treatment options are mostly limited to surgical interventions or conservative treatment, anti-inflammatory substances might offer a novel, more target-orientated therapeutic approach. Triptolide (TPL), a natural substance found in the Chinese medicinal herb Tripterygium wilfordii Hook, has been demonstrated to possess anti-inflammatory effects in various cells, but no studies exist so far for the IVD. Therefore, the aim of this study was to determine the effects of TPL on human IVD cells by analyzing changes in gene expression and underlying molecular mechanisms. MATERIALS AND METHODS: In order to investigate the anti-inflammatory, anabolic and anti-catabolic effect of TPL, dose-dependency experiments (n = 5) and time course experiments (n = 5) were performed on IL-1ß prestimulated human IVD cells and changes in gene expression of IL-6/-8, TNF-α, PGE2S, MMP1/2/3/13, aggrecan and collagen-I/-II were analyzed by real-time RT-PCR. The molecular mechanisms underlying the effects observed upon TPL treatment were investigated by analyzing involvement of Toll-like receptors TLR2/4 (real-time RT-PCR, n = 5), NF-κB, MAP kinases p38, ERK and JNK (immunoblotting and immunocytochemistry, n = 4) as well as RNA polymerase II (immunoblotting, n = 3). RESULTS: Results showed that 50 nM TPL exhibited an anti-inflammatory, anti-catabolic and anabolic effect on the mRNA level for IL-6/-8, PGE2S, MMP1/2/3/13, aggrecan, collagen-II and TLR2/4, with most pronounced changes after 18 h for proinflammatory cytokines and MMPs or 30 h for TLRs and matrix proteins. However, we also observed an up-regulation of TNF-α at higher concentrations. The effects of TPL did not seem to be mediated via an inhibition of NF-κB or a decrease of RNA polymerase II levels, but TPL influenced activity of MAP kinases p38 and ERK (but not JNK) and expression of TLR2/4. CONCLUSIONS: In conclusion, TPL may possess promising potential for the treatment of inflammation-related discogenic back pain in vitro, but its analgetic effect will need to be confirmed in an appropriate in vivo animal model.

Cell-seeded polyurethane-fibrin structures--a possible system for intervertebral disc regeneration.

Nowadays, intervertebral disc (IVD) degeneration is one of the principal causes of low back pain involving high expense within the health care system. The long-term goal is the development of a medical treatment modality focused on a more biological regeneration of the inner nucleus pulposus (NP). Hence, interest in the endoscopic implantation of an injectable material took center stage in the recent past. We report on the development of a novel polyurethane (PU) scaffold as a mechanically stable carrier system for the reimplantation of expanded autologous IVD-derived cells (disc cells) to stimulate regenerative processes and restore the chondrocyte-like tissue within the NP. Primary human disc cells were seeded into newly developed PU spheroids which were subsequently encapsulated in fibrin hydrogel. The study aims to analyze adhesion properties, proliferation capacity and phenotypic characterization of these cells. Polymerase chain reaction was carried out to detect the expression of genes specifically expressed by native IVD cells. Biochemical analyses showed an increased DNA content, and a progressive enhancement of total collagen and glycosaminoglycans (GAG) was observed during cell culture. The results suggest the synthesis of an appropriate extracellular matrix as well as a stable mRNA expression of chondrogenic and/or NP specific markers. In conclusion, the data presented indicate an alternative medical approach to current treatment options of degenerated IVD tissue.

What comprises a good outcome in spinal surgery? A preliminary survey among spine surgeons of the SSE and European spine patients.

Standardized and validated self-administered outcome-instruments are broadly used in spinal surgery. Despite a plethora of articles on outcome research, no systematic evaluation is available on what actually comprises a good outcome in spinal surgery from the patients' and surgeons' perspective, respectively. However, this is a prerequisite for improving outcome instruments. In performing a cross-sectional survey among spine patients from different European regions and spine surgeons of the SSE, the study attempted (1) to identify the most important domains determining a good outcome from a patients' as well as a surgeon's perspective, and (2) to explore regional differences in the identified domains. For this purpose, a structured interview was performed among 30 spine surgeons of the SSE and 353 spine surgery patients (representing Northern, Central and Southern Europe) to investigate their criteria for a good outcome. A qualitative and descriptive approach was used to evaluate the data. Results revealed a high agreement on what comprises a good outcome among surgeons and patients, respectively. The main parameters determining good outcome were achieving the patients' expectations/satisfaction, pain relief, improvement of disability and social reintegration. Younger patients more often expected a complete pain relief, an improved work capacity, and better social life participation. Patients in southern Europe more often wanted to improve work capacity compared to those from central and northern European countries. No substantial differences were found when patients' and surgeons' perspective were compared. However, age and differences in national social security and health care system ("black flags") have an impact on what is considered a good outcome in spinal surgery.

Lumbar spinal stenosis: assessment of cauda equina involvement by electrophysiological recordings.

UNLABELLED: The objective of this study was to investigate the relationship between electrophysiological recordings and clinical as well as radiological findings in patients suggestive to suffer from a lumbar spinal stenosis (LSS). We hypothesise that the electrophysiological recordings, especially SSEP, indicate a lumbar nerve involvement that is complementary to the neurological examination and can provide confirmatory information in less obvious clinical cases. In a prospective cohort study, 54 patients scheduled for surgery due to LSS were enrolled in an unmasked, uncontrolled trial. All patients were assessed by neurological examination, electrophysiological recordings, and magnetic resonance imaging (MRI) of the lumbar spine. The electrophysiological recordings focused on spinal lumbar nerve involvement. RESULTS: About 88% suffered from a multisegmental LSS and 91% of patients respectively complained of chronic lower back pain and/or leg pain for more than 3 months, combined with a restriction in walking distance. The neurological examination revealed only a few patients with sensory and/or motor deficits while 87% of patients showed pathological electrophysiological recordings (abnormal tibial SSEP in 78% of patients, abnormal H-reflex in 52% of patients). CONCLUSIONS: Whereas the clinical examination, even in severe LSS, showed no specific sensory-motor deficit, the electrophysiological recordings indicated that the majority of patients had a neurogenic disorder within the lumbar spine. By the pattern of bilateral pathological tibial SSEP and pathological reflexes associated with normal peripheral nerve conduction, LSS can be separated from a demyelinating polyneuropathy and mono-radiculopathy. The applied electrophysiological recordings, especially SSEP, can confirm a neurogenic claudication due to cauda equina involvement and help to differentiate neurogenic from vascular claudication or musculo-skeletal disorders of the lower limbs. Therefore, electro-physiological recordings provide additional information to the neurological examination when the clinical relevance of a radiologically-suspected LSS needs to be confirmed.

Predictors of multidimensional outcome after spinal surgery.

The variables identified as predictors of surgical outcome often differ depending on the specific outcome variable chosen to designate "success". A short set of multidimensional core outcome measures was recently developed, in which each of the following domains was addressed with a single question and then combined in an index: pain, function, symptom-specific well-being, general well-being (quality of life), disability (work and social). The present study examined the factors that predicted surgical outcome as measured using the multidimensional core measures. 163 spinal surgery patients (mixed indications) completed questionnaires before and 6 months after surgery enquiring about demographics, medical/clinical history, fear-avoidance beliefs (FABQ), depression (Zung self-rated depression), and the core measures domains. Multiple regression analyses were used to identify predictor variables for each core domain and for the multidimensional combined core-set index. The combination of baseline symptoms, medical variables (pain duration, previous spine operations, number of levels treated, operative procedure) and psychosocial factors (FABQ and Zung depression) explained 34% of the variance in the core measures index (P < 0.001). With regard to the individual domain items, the medical variables were better in predicting the items "pain" and "symptom-specific well-being" (R (2) = 6-7%) than in predicting "function", "general well-being" or "disability" (each R (2) < 4%). The inverse pattern was shown for the psychosocial predictors, which accounted for in each case approximately 20% variance in "function", "general well-being" and "disability" but only 12-14% variance in "pain" and "symptom-specific well-being". Further to previous studies establishing the sensitivity to change of the core-set, we have shown that a large proportion of the variance in its scores after surgery could be predicted by "well-known" medical and psychosocial predictor variables. This substantiates the recommendation for its further use in registry systems, quality management projects, and clinical trials.

Reliability of perioperative SSEP recordings in spine surgery.

OBJECTIVE: The reproducibility and clinical reliability of perioperative somatosensory-evoked potentials (SSEP) were prospectively evaluated in uneventful scoliosis surgery. The influence of anesthesia owing to induction of total intravenous anesthesia (TIVA) upon preoperative SSEP and the variability of intraoperative SSEP were calculated. The potential effect of spine surgery was assessed by comparing pre- to postoperative SSEP. METHODS: A total of 2,143 pre-, intra- and postoperative tibial and median SSEP recorded in 25 patients undergoing spine surgery owing to idiopathic scoliosis were analyzed. The anesthesia protocol consisted of a computerized target controlled infusion (TCI) device for propofol and intravenous application of an opioid. RESULTS: Anesthesia induced a significant and comparable prolongation of the tibial SSEP onset, P40 and P60 latencies, while the N50 latency was less changed. Throughout anesthesia, latencies of median (onset, N20, P25 and N35) and tibial (onset, P40, N50 and P60) SSEP showed mean variations of less than 6%. The intraoperative SSEP amplitudes were less stable with a relative standard deviation of 30-40%. In uneventful spine surgery, the postoperative tibial SSEP were not significantly changed in comparison to preoperative recordings. CONCLUSIONS: By using a standardized anesthesia protocol, the impact of anesthesia on preoperative SSEP can be predicted. Furthermore, the controlled application of sedatives and analgesics allows recording of stable SSEP parameters for intraoperative monitoring purposes. As in uneventful spine surgery pre- to postoperative SSEP are unchanged the latter comparison can be applied as an additional perioperative neuromonitoring procedure to assess the influence of spine surgery or other invasive interventions on spinal cord function.

2002 SSE Award Competition in Basic Science: expression of major matrix metalloproteinases is associated with intervertebral disc degradation and resorption.

During the process of degeneration, the intervertebral disc (IVD) shows a progressive and significant reduction in height due to tissue resorption. Intradiscal clefts and tears are major hallmarks of disc degeneration. Matrix-degrading enzymes such as matrix metalloproteinases (MMPs) are assumed to play a pivotal role in disc tissue degradation and resorption. The objective of this study was therefore to investigate the potential role of MMPs in extracellular matrix degradation leading to disc degeneration. This study was conducted on 30 formalin-fixed and EDTA-decalcified complete cross-sections of lumbar IVDs from cadavers of individuals aged between 0 and 86 years. Tissue sections were used for the immunolocalization of MMPs-1, -2, -3 and -9. The number of labeled cells was assessed by morphometric analyses, and was statistically correlated with the formation of clefts and tears, cellular proliferation, granular matrix changes and mucous degeneration. Furthermore, 30 disc specimens obtained during spinal surgery were used for in situ hybridization of MMP-2 and -3-mRNA. In addition, the enzymatic gelatinolytic activity was determined by in situ zymography in autopsy material. Immunohistochemistry showed the intradiscal expression of all four MMPs, which was confirmed by in situ hybridization, providing clear evidence for the synthesis of the enzymes within nucleus pulposus and annulus fibrosus cells. Gelatinolytic enzymatic activity was verified by in situ zymography. IVDs from infants and young adolescents remained almost completely unlabeled for all MMPs tested, while more MMPs-1 and -3 were seen in disc cells of younger adults than in those of a more advanced age; MMP-2 remained unchanged over the adult age periods, and MMP-9 was expressed in only relatively few cells. This pattern significantly correlated with the occurrence of clefts and tears. This correlation was strongest for MMP-1 ( P<0.0001), MMP-2 ( P<0.0017) and MMP-3 ( P<0.0005) in the nucleus, and MMP-1 ( P<0.0001) and MMP-2 ( P<0.038) in the annulus. In parallel, the proliferation of disc cells and matrix degeneration (granular changes and mucous degeneration) were related to MMP expression. Likewise, enzymatic activity was seen in association with cleft formation. Our data suggest that major MMPs play an important role in the degradation of the IVD. This is evidenced by the high correlation of MMP expression with the formation of clefts and tears. These findings implicate a leading function for MMPs in IVD degeneration resulting in the loss of normal disc function, eventually leading to low-back pain.

[Percutaneous transpedicular vertebroplasty for treatment of osteoporosis-induced vertebral fractures]. / Die perkutane transpedikuläre Vertebroplastik zur Behandlung Osteoporose bedingter Wirbelfrakturen.

Osteoporosis plays an increasing medical, social, and economic role in our society. Vertebral body fractures are the most common fractures, along with fractures around the hip joint, and fractures of the distal radius due to osteoporosis. An osteoporotic vertebral compression fracture can lead to incapacitating back pain and immobility and often requires in-hospital treatment. Vertebroplasty is an effective procedure consisting of the percutaneous injection of polymethylmethacrylate (PMMA) cement into vertebral bodies. Preliminary studies showed promising clinical results with this new technique. As there is a high incidence of cement leakage during the injection of the cement, we prefer to perform the procedure under computed tomography control with a fluoro-CT-option. Furthermore, we recommend that the procedure is only done in collaboration with a spine surgeon. In case of a neurological complication, immediate decompression of the spinal canal is mandatory. Vertebroplasty is a very promising, effective and safe method for the treatment for osteoporotic vertebral compression fractures. Based on our preliminary results, this method can be recommended for a more widespread clinical use.

Selective nerve root blocks for the treatment of sciatica: evaluation of injection site and effectiveness--a study with patients and cadavers.

PURPOSE: To relate different types of radiographic contrast material distributions to anatomic compartments by using cadaveric specimens and to relate the injection site to treatment-induced discomfort and therapeutic effect. MATERIALS AND METHODS: The contrast material distributions of selective nerve root blocks (SNRBs) in 36 patients (13 women, 23 men; mean age, 52 years; age range, 22-88 years) were graded by two radiologists in conference as type 1 (tubular appearance), type 2 (nerve root visible as filling defect), or type 3 (nerve root not visible). These patterns were correlated with pain reduction after 15 minutes and 2 weeks (with a visual analogue scale of 100-mm length). In addition, 30 nerve roots were injected with iodine-containing contrast material and blue dye in three cadaveric specimens. Radiographs were compared with anatomic sections. RESULTS: After 15 minutes and 2 weeks, 75% and 86% of the patients, respectively, reported pain relief. Mean pain relief length after 15 minutes for type 1 distribution was 60 mm; for type 2, 44 mm; and for type 3, 22 mm; and after 2 weeks, it was 34 mm for type 1, 31 mm for type 2, and 57 mm for type 3. There was no correlation between early and late response. Pain during intervention was less pronounced in type 2 injection, compared with type 1 (P = .002). On the basis of anatomic sections, type 1 injection was intraepineural; type 2, extraepineural; and type 3, paraneural. CONCLUSION: Therapeutic SNRB is effective in sciatica, but early response does not predict the effect after 2 weeks. Type 1 injections are more painful than type 2 injections.

Magnetic resonance classification of lumbar intervertebral disc degeneration.

STUDY DESIGN: A reliability study was conducted. OBJECTIVES: To develop a classification system for lumbar disc degeneration based on routine magnetic resonance imaging, to investigate the applicability of a simple algorithm, and to assess the reliability of this classification system. SUMMARY OF BACKGROUND DATA: A standardized nomenclature in the assessment of disc abnormalities is a prerequisite for a comparison of data from different investigations. The reliability of the assessment has a crucial influence on the validity of the data. Grading systems of disc degeneration based on state of the art magnetic resonance imaging and corresponding reproducibility studies currently are sparse. METHODS: A grading system for lumbar disc degeneration was developed on the basis of the literature. An algorithm to assess the grading was developed and optimized by reviewing lumbar magnetic resonance examinations. The reliability of the algorithm in depicting intervertebral disc alterations was tested on the magnetic resonance images of 300 lumbar intervertebral discs in 60 patients (33 men and 27 women) with a mean age of 40 years (range, 10-83 years). All scans were analyzed independently by three observers. Intra- and interobserver reliabilities were assessed by calculating kappa statistics. RESULTS: There were 14 Grade I, 82 Grade II, 72 Grade III, 68 Grade IV, and 64 Grade V discs. The kappa coefficients for intra- and interobserver agreement were substantial to excellent: intraobserver (kappa range, 0.84-0.90) and interobserver (kappa range, 0.69-0.81). Complete agreement was obtained, on the average, in 83.8% of all the discs. A difference of one grade occurred in 15.9% and a difference of two or more grades in 1.3% of all the cases. CONCLUSION: Disc degeneration can be graded reliably on routine T2-weighted magnetic resonance images using the grading system and algorithm presented in this investigation.

Therapeutic efficacy of selective nerve root blocks in the treatment of lumbar radicular leg pain.

The objective of this study was to investigate the clinical effectiveness of nerve root blocks (i.e., periradicular injection of bupivacaine and triamcinolone) for lumbar monoradiculopathy in patients with a mild neurological deficit. We have retrospectively analysed 30 patients (29-82 years) with a minor sensory/motor deficit and an unequivocal MRI finding (20 disc herniations, 10 foraminal stenoses) treated with a selective nerve root block. Based on the clinical and imaging findings, surgery (decompression of the nerve root) was justifiable in all cases. Twenty-six patients (87%) had rapid (1-4 days) and substantial regression of pain, five required a repeat injection. 60% of the patients with disc herniation or foraminal stenosis had permanent resolution of pain, so that an operation was avoided over an average of 16 months (6-23 months) follow-up. Nerve root blocks are very effective in the non-operative treatment of minor monoradiculopathy and should be recommended as the initial treatment of choice for this condition.

Painful Lumbar Disk Derangement: Relevance of Endplate Abnormalities at MR Imaging.

PURPOSE: To investigate the predictive value of magnetic resonance (MR) imaging of abnormalities of the lumbar intervertebral disks, particularly with adjacent endplate changes, to predict symptomatic disk derangement, with discography as the standard. MATERIALS AND METHODS: Fifty patients aged 28-50 years with chronic low back pain and without radicular leg pain underwent prospective clinical examination and sagittal T1- and T2-weighted and transverse T2-weighted MR imaging. Subsequently, patients underwent lumbar discography with a pain provocation test (116 disks). MR images were evaluated for disk degeneration, a high-signal-intensity zone, and endplate abnormalities. Results of pain provocation at discography were rated independently of the image findings as concordant or as nonconcordant or painless. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated to assess the clinical relevance of MR abnormalities. RESULTS: Normal disks on MR images were generally not painful at provocative discography (NPV, 98%). Disk degeneration (sensitivity, 98%; specificity, 59%; PPV, 63%) and a high-signal-intensity zone (sensitivity, 27%; specificity, 85%; PPV, 56%) were not helpful in the identification of symptomatic disk derangement. When only moderate and severe type I and type II endplate abnormalities were considered abnormal, all injected disks caused concordant pain with provocation (sensitivity, 38%; specificity, 100%; PPV, 100%). CONCLUSION: Moderate and severe endplate abnormalities appear be useful in the prediction of painful disk derangement in patients with symptomatic low back pain.

MR morphology of alar ligaments and occipitoatlantoaxial joints: study in 50 asymptomatic subjects.

PURPOSE: To assess the magnetic resonance (MR) imaging appearance of the alar ligaments and joints in the upper cervical spine to determine the prevalence of structural alterations in asymptomatic individuals. MATERIALS AND METHODS: Fifty healthy individuals (31 men, 19 women) with a mean age of 30 years (range, 19-47 years) underwent coronal T1- and T2-weighted and transverse T1-weighted MR imaging. MR findings were analyzed independently by two musculoskeletal radiologists, with disagreements resolved in conference. RESULTS: Alar ligaments were detected in 42 (84%) (left side) and 38 (76%) (right side) of 50 individuals. The majority of ligaments (88%) and joints (58%) of the craniocervical junction (CCJ) were asymmetric. Asymmetry of the joint between C1 and C2 was less frequent (46%). Small amounts of fluid were detected in 8% of CCJ joints and 56% of C1-C2 joints in asymptomatic individuals. CONCLUSION: Asymmetry of alar ligaments, CCJ and C1-C2 facet joints, and joint effusions are common in asymptomatic individuals. The clinical relevance of these MR findings is therefore limited in the identification of the source of neck pain in symptomatic patients.

Retroperitoneal endoscopically assisted minilaparotomy for anterior lumbar interbody fusion: technical feasibility and complications.

STUDY DESIGN: Description of a novel less invasive technique and prospective evaluation of associated morbidity and potential complications. OBJECTIVE: To investigate the feasibility of a novel endoscope-assisted retroperitoneal approach (REAM) for anterior lumbar interbody fusion (ALIF). SUMMARY OF BACKGROUND DATA: Minimally and less invasive approaches are currently favored to perform ALIF. However, the present endoscopic techniques have not found widespread acceptance, because they are technically demanding, and microsurgical techniques are not time effective when two separate approaches are needed for L5-S1 (transperitoneal) and L4-L5 (retroperitoneal). METHODS: The authors have developed the technique of REAM, which consists of three stages: 1) endoscopic retroperitoneal mobilization of the peritoneal sac, 2) midline minilaparotomy (4-6 cm), and 3) standard open anterior lumbar interbody fusion. Twenty patients were prospectively enrolled in this study and perioperative data (i.e., blood loss, operative time, intra- and postoperative complications) were collected to assess the feasibility of this approach. RESULTS: Six single-level and 14 two-level ALIFs from L3-L4 to L5-S1 were performed with a mean operative time of 108 minutes (range, 85-150) and an average estimated blood loss of 200 mL (range, 50-500). The follow-up (range, 12-29 months) on 20 patients showed that there were no perioperative or postoperative complications related directly to this approach. CONCLUSION: Anterior lumbar interbody fusion by REAM can be performed without additional hazard to the patient and appears to be a reasonable alternative to existing less invasive procedures.

Subacute subdural haematoma complicating lumbar microdiscectomy.

There have been no previous reports of a spinal subdural haematoma occurring as a complication of spinal surgery. We highlight the pitfalls in the diagnosis and management of a subacute subdural haematoma resulting from a dural tear which occurred as a surgical complication of microdiscectomy.

[Acute myelopathy and cauda equina syndrome]. / Akute Myelopathie und Cauda-equina-Syndrom.

The high incidence of non-specific, benign back trouble often delays the diagnosis of specific causes of back pain and thus result in neurological deficits. Degenerative abnormalities in the cervical spine may narrow the spinal canal and result in acute myelopathy subsequent to minor injuries. Large cervical or lumbar disc herniations causing myelon, conus or cauda equina compression are rare but must not be overlooked. Spinal metastases may remain unrecognised for a long period and lead to the correct diagnosis only after presentation with neurological deficits. Acute myelopathy or cauda equina syndrome are indications for immediate diagnostic assessment and treatment in a spine centre.

Functional MR imaging of the craniocervical junction. Correlation with alar ligaments and occipito-atlantoaxial joint morphology: a study in 50 asymptomatic subjects.

PURPOSE: Whiplash injuries are frequent in industrialized countries. The acute and chronic symptoms following such injuries are incompletely understood and objective clinical or imaging findings are rare. Several authors have suspected that rear end collisions occurring when the head is rotated may result in tears of the alar ligaments. There has been experimental proof that a torn alar ligament increases the rotation of the C0/C1 and C1/C2 segments to the contralateral side. Functional cross sectional imaging has therefore been proposed to diagnose injuries of the alar ligaments. So far, published data on normal ranges of rotation in an asymptomatic population have been sparse. The aim of this study was to determine by MR imaging the normal range of rotation in the first three cervical segments and their relation to the morphology of the alar ligaments and the occipito-atlantoaxial joints. MATERIAL AND METHODS: Functional MR imaging of the craniocervical junction in maximum active left and right head rotation was performed in 50 healthy volunteers with a mean age of 29.8 years (31 men, 19 women, range 19-47 years). Measurements were independently performed by two musculoskeletal radiologists to assess interobserver error. The results were correlated with gender and age, with morphological findings in the occipito-atlantoaxial joints (i.e. joint symmetry, joint effusions, dens position), and with the form, course and symmetry of the alar ligaments. RESULTS: The mean range of rotation for the C0/C1 joint was 2.7 degrees (standard deviation [SD] 3.3 degrees)/3.3 degrees (SD 3.6 degrees) (right/left) and at the C1/C2 level 38 degrees (SD 6.5 degrees)/37.8 degrees (SD 6.4 degrees). The mean differences in left/right rotation were: C0/C1 3.5 degrees (SD 2.8 degrees) and C1/C2 6.3 degrees (SD 4.4 degrees). No correlation was found between segmental rotation and morphological characteristics of the craniocervical joints or ligament structures. CONCLUSION: There is wide variation of segmental motion in the upper cervical spine. Differences in right-to-left rotation are frequently encountered in an asymptomatic population. Therefore, these measurements are unsuitable for indirect diagnosis of soft tissue lesions after whiplash injury and should not be used as a basis for treatment guidelines.