Differential Outcomes of Infection by Wild-Type SARS-CoV-2 and the B.1.617.2 and B.1.1.529 Variants of Concern in K18-hACE2 Transgenic Mice

BACKGROUND

SARS-CoV-2 is a respiratory virus with neurological complications including the loss of smell and taste, headache, and confusion that can persist for months or longer. Severe neuronal cell damage has also been reported in some cases. The objective of this study was to compare the infectivity of the wild-type virus, Delta (B.1.617.2) and Omicron (B.1.1.529) variants in transgenic mice that express the human angiotensin-converting enzyme 2 (hACE2) receptor under the control of the keratin 18 promoter (K18) and characterize the progression of infection and inflammatory response in the lungs, brain, medulla oblongata, and olfactory bulbs of these animals. We hypothesized that wild type, Delta and Omicron differentially infect K18-hACE2 mice, thereby inducing distinct cellular responses.

METHODS

K18-hACE2 female mice were intranasally infected with wild-type, Delta, or Omicron variants and euthanized either at 3 days post-infection (dpi) or at the humane endpoint. None of the animals infected with the Omicron variant reached the humane endpoint and were euthanized at day 8 dpi. Virological and immunological analyses were performed in the lungs, brains, medulla oblongata and olfactory bulbs isolated from infected mice.

RESULTS

At 3 dpi, mice infected with wild type and Delta displayed significantly higher levels of viral RNA in the lungs than mice infected with Omicron, while in the brain, Delta and Omicron resulted in higher levels of viral RNA than with the wild type. Viral RNA was also detected in the medulla oblongata of mice infected by all these virus strains. At this time point, the mice infected with wild type and Delta displayed a marked upregulation of many inflammatory markers in the lungs. On the other hand, the upregulation of inflammatory markers was observed only in the brains of mice infected with Delta and Omicron. At the humane endpoint, we observed a significant increase in the levels of viral RNA in the lungs and brains of mice infected with wild type and Delta, which was accompanied by the elevated expression of many inflammatory markers. In contrast, mice which survived infection with the Omicron variant showed high levels of viral RNA and the upregulation of cytokine and chemokine expression only in the lungs at 8 dpi, suggesting that infection and inflammatory response by this variant is attenuated in the brain. Reduced RNA levels and the downregulation of inflammatory markers was also observed in the medulla oblongata and olfactory bulbs of mice infected with Omicron at 8 dpi as compared with mice infected with wild-type and Delta at the humane end point. Collectively, these data demonstrate that wild-type, Delta, and Omicron SARS-CoV-2 induce distinct levels of infection and inflammatory responses in K18-hACE2 mice. Notably, sustained brain infection accompanied by the upregulation of inflammatory markers is a critical outcome in mice infected with wild type and Delta but not Omicron.

Central carbon metabolism remodeling as a mechanism to develop drug tolerance and drug resistance in Mycobacterium tuberculosis

Suboptimal efficacy of the current antibiotic regimens and frequent emergence of antibiotic-resistant Mycobacterium tuberculosis (Mtb), an etiological agent of tuberculosis (TB), render TB the world’s deadliest infectious disease before the COVID-19 outbreak. Our outdated TB treatment method is designed to eradicate actively replicating populations of Mtb. Unfortunately, accumulating evidence suggests that a small population of Mtb can survive antimycobacterial pressure of antibiotics by entering a “persister” state (slowly replicating or non-replicating and lacking a stably heritable antibiotic resistance, termed drug tolerance). The formation of drug-tolerant Mtb persisters is associated with TB treatment failure and is thought to be an adaptive strategy for eventual development of permanent genetic mutation-mediated drug resistance. Thus, the molecular mechanisms behind persister formation and drug tolerance acquisition are a source of new antibiotic targets to eradicate both Mtb persisters and drug-resistant Mtb. As Mtb persisters are genetically identical to antibiotic susceptible populations, metabolomics has emerged as a vital biochemical tool to differentiate these populations by determining phenotypic shifts and metabolic reprogramming. Metabolomics, which provides detailed insights into the molecular basis of drug tolerance and resistance in Mtb, has unique advantages over other techniques by its ability to identify specific metabolic differences between the two genetically identical populations. This review summarizes the recent advances in our understanding of the metabolic adaptations used by Mtb persisters to achieve intrinsic drug tolerance and facilitate the emergence of drug resistance. These findings present metabolomics as a powerful tool to identify previously unexplored antibiotic targets and improved combinations of drug regimens against drug-resistant TB infection.

Improving consultations for persistent musculoskeletal low back pain in orthopaedic spine settings: an intervention development

BACKGROUND

There is a need to improve consultations between patients with persistent musculoskeletal low back pain and orthopaedic spine clinicians when surgery is not indicated. Poor communication and lack of education about self- management in these consultations have been shown to be associated with increased distress and higher subsequent health care seeking.

AIM

To develop a standardised intervention to improve spine care consultations for patients for whom surgery is not beneficial.

METHOD

The intervention was developed in six stages. The first three stages included: interviews with patients, an interactive workshop with clinicians from a mix of disciplines, and interviews with spine clinicians about their perspective of the recommendations, their perceived difficulties and potential improvements. Information from these stages was synthesised by an expert panel, creating a draft intervention structure and content. The main features of the intervention and the materials developed were then reviewed by patients and spine clinicians. Finally, the research team incorporated the recommended amendments to produce the intervention.

RESULTS

In total, 36 patients and 79 clinicians contributed to the development of the intervention. The final intervention includes three components: a pre-consultation letter with information suggesting that surgery is one possible intervention amongst many, introducing the staff, and alerting patients to bring with them a potted history of interventions tried previously. The intervention includes short online training sessions to improve clinicians' communication skills, during the consultation, in reference to listening skills, validation of patients' pain, and use of appropriate language. Clinicians are also supplied with a list of evidence-based sources for advice and further information to share with patients. Finally, post consultation, a follow up letter includes a short summary of the patients' clinical journey, the results of their examination and tests, and a reminder of recommendations for self-management.

CONCLUSION

The intervention includes aspects around patient education and enhanced clinician skills. It was developed with input from a multitude of stakeholders and is based on patients' perceptions of what they would find reassuring and empowering when surgery is excluded. The intervention has the potential to improve the patients care journey and might lead to changes in practice in spine clinicians.

Taking patients to the ice cream shop but telling them that they cannot have ice cream: a qualitative study of orthopaedic spine clinicians' perceptions of persistent low back pain consultations

OBJECTIVE

This study aimed to explore the perceptions of orthopaedic clinicians about consultations for people with persistent musculoskeletal low back pain (PMLBP) in which surgery is not recommended. Surgery is not recommended for the majority of PMLBP consulting in secondary care settings.

SETTING

Secondary care sector in the UK.

PARTICIPANTS

Semi-structured qualitative interviews were conducted with 24 orthopaedic team clinicians from 17 different hospitals in the UK and Ireland. Interviews explored clinicians' perceptions of the challenges in consultations where surgery is not indicated. Interviews were transcribed verbatim and analysed using thematic analysis.

RESULTS

Two meta-themes, Difficulties and Enablers, each consisting of several subthemes were identified. Difficulties included challenges around the choice of appropriate terminology and labels for PMLBP, managing patients' expectations, working with mentally vulnerable patients and explaining imaging findings. Enablers included early management of expectations, use of routine imaging, triaging, access to direct referral elsewhere, including other non-surgical practitioners in the team, training to improve communication skills and understanding of psychological issues.

CONCLUSION

The findings highlight clinicians' perceived need for concordance in messages delivered across the care pathway and training of orthopaedic clinicians to deliver effective reassurance and address patients' needs in circumstances where surgery is not indicated.

Ability of Spine Specialists to Identify Psychosocial Risk Factors as Obstacles to Recovery in Patients with Low Back Pain-Related Disorders

Study Design

Prospective study.

Purpose

Yellow flags are psychosocial associated with a greater likelihood of progression to persistent pain and disability. These are referred to as obstacles to recovery. Despite their recognized importance, it is unknown how effective clinicians are in detecting them. The primary objective of this study was thus to determine the effectiveness of spine specialist clinicians in detecting the presence of yellow flags in patients presenting to an orthopedic outpatient clinic with low back-related disorders.

Overview of Literature

Psychosocial factors have been previously studied as important predictors of prognosis in patients with low back pain. However, the ability of spinal specialist to identify them remains unknown.

Methods

A prospective, single-center, consecutive cohort study was conducted over a period of 30 months. All new patients with low back-related disorders regardless of pathology completed a Yellow Flag Questionnaire that was adapted from the psychosocial flags framework. Clinicians assessing these patients completed a standardized form to determine which and how many yellow flags they had identified during the consultation.

Results

A total of 130 patients were included in the analysis, and the clinicians reported an average of 5 flags (range, 0–9). Fear of movement or injury was the most frequently reported yellow flag, reported by 87.7% (n=114) of patients. Clinician sensitivity in detecting yellow flags was poor, correctly identifying only 2 flags, on average, of the 5 reported by patients, with an overall sensitivity of only 39%.

Conclusions

The ability of spine specialists to identify yellow flags is poor and can be improved by asking patients to complete a simple screening questionnaire.

Understanding cauda equina syndrome: protocol for a UK multicentre prospective observational cohort study

INTRODUCTION

Cauda equina syndrome (CES) is a potentially devastating condition caused by compression of the cauda equina nerve roots. This can result in bowel, bladder and sexual dysfunction plus lower limb weakness, numbness and pain. CES occurs infrequently, but has serious potential morbidity and medicolegal consequences. This study aims to identify and describe the presentation and management of patients with CES in the UK.

METHODS AND ANALYSIS

Understanding Cauda Equina Syndrome (UCES) is a prospective and collaborative multicentre cohort study of adult patients with confirmed CES managed at specialist spinal centres in the UK. Participants will be identified using neurosurgical and orthopaedic trainee networks to screen referrals to spinal centres. Details of presentation, investigations, management and service usage will be recorded. Both patient-reported and clinician-reported outcome measures will be assessed for 1 year after surgery. This will establish the incidence of CES, current investigation and management practices, and adherence to national standards of care. Outcomes will be stratified by clinical presentation and patient management. Accurate and up to date information about the presentation, management and outcome of patients with CES will inform standards of service design and delivery for this important but infrequent condition.

ETHICS AND DISSEMINATION

UCES received a favourable ethical opinion from the South East Scotland Research Ethics Committee 02 (Reference: 18/SS/0047; IRAS ID: 233515). All spinal centres managing patients with CES in the UK will be encouraged to participate in UCES. Study results will be published in medical journals and shared with local participating sites.

TRIAL REGISTRATION NUMBER

ISRCTN16828522; Pre-results.

PKD1 protein is involved in reactive oxygen species-mediated mitochondrial depolarization in cooperation with protein kinase Cδ (PKCδ)

In this study, we used gene targeting in mice to identify the in vivo functions of PKD1. In addition to phenotypically characterizing the resulting knock-out animals, we also used mouse embryonic fibroblasts to investigate the associated signaling pathways in detail. This study is the first to use genetic deletion to reveal that PKD1 is a key regulator involved in determining the threshold of mitochondrial depolarization that leads to the production of reactive oxygen species. In addition, we also provide clear evidence that PKCδ is upstream of PKD1 in this process and acts as the activating kinase of PKD1. Therefore, our in vivo data indicate that PKD1 functions not only in the context of aging but also during nutrient deprivation, which occurs during specific phases of tumor growth.

A comparison of patient-reported outcome measures after spinal surgery

Minimal clinically important differences (MCID) in the scores of patient-reported outcome measures allow clinicians to assess the outcome of intervention from the perspective of the patient. There has been significant variation in their absolute values in previous publications and a lack of consistency in their calculation.

The purpose of this study was first, to establish whether these values, following spinal surgery, vary depending on the surgical intervention and their method of calculation and secondly, to assess whether there is any correlation between the two external anchors most frequently used to calculate the MCID.

We carried out a retrospective analysis of prospectively gathered data of adult patients who underwent elective spinal surgery between 1994 and 2009. A total of 244 patients were included. There were 125 men and 119 women with a mean age of 54 years (16 to 84); the mean follow-up was 62 months (6 to 199) The MCID was calculated using three previously published methods.

Our results show that the value of the MCID varies considerably with the operation and its method of calculation. There was good correlation between the two external anchors. The global outcome tool correlated significantly better.

We conclude that consensus needs to be reached on the best method of calculating the MCID. This then needs to be defined for each spinal procedure. Using a blanket value for the MCID for all spinal procedures should be avoided.

Cite this article: Bone Joint J 2015;97-B:366–71.

A comparative study of the outcomes of primary and revision lumbar discectomy surgery

The outcome of surgery for recurrent lumbar disc herniation is debatable. Some studies show results that are comparable with those of primary discectomy, whereas others report worse outcomes. The purpose of this study was to compare the outcome of revision lumbar discectomy with that of primary discectomy in the same cohort of patients who had both the primary and the recurrent herniation at the same level and side.

A retrospective analysis of prospectively gathered data was undertaken in 30 patients who had undergone both primary and revision surgery for late recurrent lumbar disc herniation. The outcome measures used were visual analogue scales for lower limb (VAL) and back (VAB) pain and the Oswestry Disability Index (ODI).

There was a significant improvement in the mean VAL and ODI scores (both p < 0.001) after primary discectomy. Revision surgery also resulted in improvements in the mean VAL (p < 0.001), VAB (p = 0.030) and ODI scores (p < 0.001). The changes were similar in the two groups (all p > 0.05).

Revision discectomy can give results that are as good as those seen after primary surgery.

Cite this article: Bone Joint J 2013;95-B:90–4.

Dose response and structural injury in the disability of spinal injury

INTRODUCTION

In traumatic injury there is a clear relationship between the dose of energy involved, structural tissue damage and resultant disability after recovery. This relationship is often absent in cases of non-specific chronic low back pain that is perceived by patients as attributed to a workplace injury. There are many studies assessing risk factors for non-specific low back pain. However, studies addressing causality of back pain are deficient.

PURPOSE

To establish whether there exists a causal relationship between structural injury, low back pain and spinal disability.

METHODS

Retrospective analysis of prospectively gathered validated spinal outcome measures [Oswestry disability index (ODI), low back outcome score (LBO), modified somatic perception (MSP), modified Zung depression index (MZD)] between patients with healed high energy thoracolumbar spinal fractures and patients with self-perceived work-related low back pain. Causality was established according to two of Bradford Hill's criteria of medical causality, temporal and dose-response relationships.

RESULTS

Twenty-three patients with spinal fractures (group 1) of average age 44 years were compared to 19 patients with self-reported back pain in the workplace pursuing claims for compensation (group 2) of average age 48 years. Both groups were comparable in terms of age and sex. The average ODI in group 1 was 28 % (SD 19) compared to 42 % (SD 19) in group 2 (P < 0.05). Similarly, LBOS was 39.7 versus 24.3 (P < 0.05), MSP 4.3 versus 9.3 (P < 0.05) and MZD 20.2 versus 34.8 (P < 0.05) in groups 1 and 2, respectively.

CONCLUSION

Despite high-energy trauma and significant structural damage to the spine, patients with the high energy injuries had better spinal outcome scores in all measures. There is no 'dose-response' relationship between structural injury, low back pain and spinal disability. This is the reverse of what would be anticipated if structural injury was the cause of disability in workplace reported onset of low back pain.

Dual pathology as a result of spinal stenosis and vitamin B12 deficiency

Vitamin B12 deficiency can confound the clinical assessment of patients presenting with features of spinal disorders. Speciality practice within spinal surgery may lead the clinician to a focus upon spinal explanations for symptoms and that belief may be reinforced by supporting imaging. In the presence of mainly sensory symptoms consideration and exclusion of non surgical causes needs to occur. This study aimed at identifying the prevalence of vitamin B12 deficiency; the presence of dual pathology on imaging performed; the implementation of replacement therapy and their subsequent clinical response as perceived by patients. This was performed through a retrospective review of patients presenting to specialist spine out-patient clinics over a 4-year period via access to pathology reports followed by a telephone survey. 457 patients were investigated of which 8.5% were vitamin B12 deficient. 70% of patients had repeat levels and 31% continued to be deficient. 26% of these patients were not placed on any supplemental therapy. 72% of patients on treatment had self perceived improved outcomes as compared with 55% not on treatment. 73% of patients underwent MRI/CT imaging. 59% of which had evidence of spinal stenosis. In older patients with sensory symptoms, the coexistence of B12 deficiency should be considered. Detection of deficiency with consequent treatment results in better global outcomes than no treatment. Unless the correct blood test is done, the pathology will remain undetected, and patients may continue with their primary symptoms despite high-risk spinal surgical procedures.

Type II odontoid fractures in the elderly: an evidence-based narrative review of management

Considerable controversy exists regarding the optimal management of elderly patients with type II odontoid fractures. There is uncertainty regarding the consequences of non-union. The best treatment remains unclear because of the morbidity associated with prolonged cervical immobilisation versus the risks of surgical intervention. The objective of the study was to evaluate the published literature and determine the current evidence for the management of type II odontoid fractures in elderly. A search of the English language literature from January 1970 to date was performed using Medline and the following keywords: odontoid, fractures, cervical spine and elderly. The search was supplemented by cross-referencing between articles. Case reports and review articles were excluded although some were referred to in the discussion. Studies in patients aged 65 years with a minimum follow-up of 12 months were selected. One-hundred twenty-six articles were reviewed. No class I study was identified. There were two class II studies and the remaining were class III. Significant variability was found in the literature regarding mortality and morbidity rates in patients treated with and without halo vest immobilisation. In recent years several authors have claimed satisfactory results with anterior odontoid screw fixation while others have argued that this may lead to increased complications in this age group. Lately, the posterior cervical (Goel-Harms) construct has also gained popularity amongst surgeons. There is insufficient evidence to establish a standard or guideline for odontoid fracture management in elderly. While most authors agree that cervical immobilisation yields satisfactory results for type I and III fractures in the elderly, the optimal management for type II fractures remain unsolved. A prospective randomised controlled trial is recommended.

Radical and débridement surgery for tuberculosis of the spine in children: a preliminary analysis of results from a 17-year prospective study

We reviewed 80 children (39 male, 41 female) with tuberculosis of the spine, all of whom were subjects of the Medical Research Council Working Party's study in Hong Kong. Forty-seven children were treated with radical surgery and the remaining 33 with débridement surgery. The mean ages at operation for radical surgery and débridement were 7.6 and 5.1 years respectively, and the mean post-operative follow-up was 15.3 and 19.7 years respectively. The clinical and radiological data obtained pre-operatively, 6 months, 1 year and 5 years post-operatively, and at final follow-up were analysed. Neither patients treated with radical nor those treated with débridement surgery had pain or neurological deficit at final follow-up. In the radical surgery group, there was a reduction of the angles of kyphosis and deformity following surgery, which was maintained throughout subsequent follow-up years. However, in the débridement surgical group, there was an increase in the angles of kyphosis and deformity following surgery, which showed a tendency to spontaneous correction in the long term. In this study we did not observe any progressive kyphosis in either group.

The accuracy of assessment of walking distance in the elective spinal outpatients setting

Self reported walking distance is a clinically relevant measure of function. The aim of this study was to define patient accuracy and understand factors that might influence perceived walking distance in an elective spinal outpatients setting. A prospective cohort study. 103 patients were asked to perform one test of distance estimation and 2 tests of functional distance perception using pre-measured landmarks. Standard spine specific outcomes included the patient reported claudication distance, Oswestry disability index (ODI), Low Back Outcome Score (LBOS), visual analogue score (VAS) for leg and back, and other measures. There are over-estimators and under-estimators. Overall, the accuracy to within 9.14 metres (m) (10 yards) was poor at only 5% for distance estimation and 40% for the two tests of functional distance perception. Distance: Actual distance 111 m; mean response 245 m (95% CI 176.3-314.7), Functional test 1 actual distance 29.2 m; mean response 71.7 m (95% CI 53.6-88.9) Functional test 2 actual distance 19.6 m; mean response 47.4 m (95% CI 35.02-59.95). Surprisingly patients over 60 years of age (n = 43) are twice as accurate with each test performed compared to those under 60 (n = 60) (average 70% overestimation compared to 140%; p = 0.06). Patients in social class I (n = 18) were more accurate than those in classes II-V (n = 85): There was a positive correlation between poor accuracy and increasing MZD (Pearson's correlation coefficient 0.250; p = 0.012). ODI, LBOS and other parameters measured showed no correlation. Subjective distance perception and estimation is poor in this population. Patients over 60 and those with a professional background are more accurate but still poor.

Corticosteroids in peri-radicular infiltration for radicular pain: a randomised double blind controlled trial. One year results and subgroup analysis

The objective of this study is to evaluate the efficacy of corticosteroids in patients with radicular pain due to lumbar disc herniation or lumbar spinal stenosis through a prospective randomised, double blind controlled trial, and whether there was an effect on subsequent interventions such as additional root blocks or surgery. Peri-radicular infiltration of corticosteroids has previously been shown to offer no additional benefit in patients with sciatica compared to local anaesthetic alone. It is not known if the response to peri-radicular infiltration is less marked in certain subgroups of patients such as those with radicular pain due to lumbar spinal stenosis. Previous studies have suggested that peri-radicular infiltration of corticosteroids may obviate the need for subsequent interventions and we therefore further investigated this in the current study. We randomised 150 patients to receive a single injection with either bupivacaine alone or bupivacaine and methylprednisolone. Patients were assessed at 6 weeks and 3 months after the injection using standard outcome measures including Oswestry Disability Index (ODI), visual analogue score for leg pain and patient's subjective assessment of outcome. At 1-year follow-up, we looked at the outcome in terms of the need for subsequent interventions such as additional root blocks or surgery. At 3-month follow-up, there was no statistically significant difference in the standard outcome measures between the two injection groups. At a minimum 1-year post injection, there was no difference in the need for subsequent interventions in either group. Patients with lumbar spinal stenosis had a less marked reduction in the ODI at 3 months with a mean change of 3.3 points when compared with 15 points for patients with lumbar disc herniation. In conclusion, peri-radicular infiltration of corticosteroids for sciatica does not provide any additional benefit when compared to local anaesthetic injection alone. Corticosteroids do not obviate the need for subsequent interventions such as additional root blocks or surgery.

Patient information and education with modern media: the Spine Society of Europe Patient Line

The role of the patient as an active partner in health care, and not just a passive object of diagnostic testing and medical treatment, is widely accepted. Providing information to patients is considered a crucial issue and the central focus in patient educational activities. It is necessary to educate patients on the nature of the outcomes and the benefits and risks of the procedures to involve them in the decision-making process and enable them to achieve fully informed consent. Information materials must contain scientifically reliable information and be presented in a form that is acceptable and useful to patients. Given the mismatch between public beliefs and current evidence, strategies for changing the public perceptions are required. Traditional patient education programmes have to face the potential barriers of storage, access problems and the need to keep content materials up to date. A computer-based resource provides many advantages, including "just-in-time" availability and a private learning environment. The use of the Internet for patient information needs will continue to expand as Internet access becomes readily available. However, the problem is no longer in finding information, but in assessing the credibility and validity of it. Health Web sites should provide health information that is secure and trustworthy. The large majority of the Web sites providing information related to spinal disorders are of limited and poor quality. Patient Line (PL), a patient information section in the Web site of Eurospine, was born in 2005 to offer patients and the general population the accumulated expertise represented by the members of the society and provide up-to-date information related to spinal disorders. In areas where evidence is scarce, Patient Line provides a real-time opinion of the EuroSpine membership. The published data reflect the pragmatic and the common sense range of treatments offered by the Eurospine membership. The first chapters have been dedicated to sciatica, scoliosis, cervical pain syndromes, low back pain and motion preservation surgery. Since 2008, the information has been available in English, German, French and Spanish. The goal is for Patient Line to become THE European patient information Web site on spinal disorders, providing reliable and updated best practice and evidence-based information where the evidence exists.

The prediction of outcome in somatised patients undergoing elective lumbar surgery

We compared a group of 46 somatised patients with a control group of 41 non-somatised patients who had undergone elective surgery to the lumbar spine in an attempt to identify pre-operative factors which could predict the outcome. In a prospective single-centre study, the Distress and Risk Assessment method consisting of a modified somatic perception questionnaire and modified Zung depression index was used pre-operatively to identify somatised patients. The type and number of consultations were correlated with functional indicators of outcome, such as the Oswestry disability index and a visual analogue score for pain in the leg after follow-up for six and 12 months.

Similar improvements in the Oswestry disability index were found in the somatised and non-somatised groups. Somatised patients who had a good outcome on the Oswestry disability index had an increased number of orthopaedic consultations (50 of 83 patients (60%) vs 29 of 73 patients (39.7%); p = 0.16) and waited less time for their surgery (5.5 months) (sd 5.26) vs 10.1 months (sd 6.29); p = 0.026). No other identifiable factors were found. A shorter wait for surgery appeared to predict a good outcome. Early review by a spinal surgeon and a reduced waiting time to surgery appear to be of particular benefit to somatised patients.

A comparison of functional assessment instruments and work status in chronic back pain

AIM

The aim of this cross sectional study was to analyse whether low back pain (LBP) functional assessment instruments correlate well with work status measures.

METHODS

This study was a cross sectional study that enrolled 375 patients with chronic LBP attending back pain outpatient clinics of a University Hospital and a specialist rehabilitation centre over a period of one year. The outcome scores measured were Oswestry Disability Index, Roland Morris Disability Questionnaire and Orebro Musculoskeletal Pain Questionnaire. The effect of back pain on their work status was also recorded and correlated to the above instrument values.

RESULTS

There was a only a modest correlation between work status and the three measured outcome scores, with the Spearman rank correlation being 0.47 for OMPQ, 0.43 for ODI and 0.39 for RMQ.

CONCLUSION

The studied standard LBP outcome measures and work status are not interchangeable. The impact on work status should not be assumed based on the severity of these outcome measures and should be recorded as a separate outcome measure in chronic low back pain.

Cauda equina syndrome treated by surgical decompression: the influence of timing on surgical outcome

A prospective longitudinal inception cohort study of 33 patients undergoing surgery for cauda equina syndrome (CES) due to a herniated lumbar disc. To determine what factors influence spine and urinary outcome measures at 3 months and 1 year in CES specifically with regard to the timing of onset of symptoms and the timing of surgical decompression. CES consists of signs and symptoms caused by compression of lumbar and sacral nerve roots. Controversy exists regarding the relative importance of timing of surgery as a prognostic factor influencing outcome. Post-operative outcome was assessed at 3 months and 1 year using the Oswestry Disability Index (ODI), Visual Analogue Scale (VAS) scores for leg and back pain and an incontinence questionnaire. Statistical analysis was used to determine the association between pre-operative variables and these post-operative outcomes with a specific emphasis on the timing of surgery. Surgery was performed on 12 (36%) patients within 48 h of the onset of symptoms including seven patients (21%) who underwent surgery within 24 h. Follow up was achieved in 27 (82%) and 25 (76%) patients at 3 and 12 months, respectively. There was no statistically significant difference in outcome between three groups of patients with respect to length of time from symptom onset to surgery- <24, 24-48 and >48 h. A significantly better outcome was found in patients who were continent of urine at presentation compared with those who were incontinent. The duration of symptoms prior to surgery does not appear to influence the outcome. This finding has significant implications for the medico-legal sequelae of this condition. The data suggests that the severity of bladder dysfunction at the time of surgery is the dominant factor in recovery of bladder function.

The development of an evidence-based patient booklet for patients undergoing lumbar discectomy and un-instrumented decompression

Post-operative management after lumbar surgery is inconsistent leading to uncertainty amongst surgeons and patients about post-operative restrictions, reactivation, and return to work. This study aimed to review the evidence on post-operative management, with a view to developing evidence-based messages for a patient booklet on post-operative management after lumbar discectomy or un-instrumented decompression. A systematic literature search produced a best-evidence synthesis of information and advice on post-operative restrictions, activation, rehabilitation, and expectations about outcomes. Evidence statements were extracted and developed into patient-centred messages for an educational booklet. The draft text was evaluated by peer and patient review. The literature review found little evidence for post-operative activity restrictions, and a strong case for an early active approach to post-operative management. The booklet was built around key messages derived from the literature review and aimed to reduce uncertainty, promote positive beliefs, encourage early reactivation, and provide practical advice on self-management. Feedback from the evaluations were favourable from both review groups, suggesting that this evidence-based approach to management is acceptable and it has clinical potential.

Randomised placebo-controlled trial on the effectiveness of nasal salmon calcitonin in the treatment of lumbar spinal stenosis

This is a double blind randomised controlled trial to assess the effectiveness of nasal salmon calcitonin in the treatment of lumbar spinal stenosis. The trial compared the outcome of salmon calcitonin nasal spray to placebo nasal spray in patients with MRI confirmed lumbar spinal stenosis. Lumbar spinal stenosis is one of the commonest conditions encountered by spine surgeons. It more frequently affects elderly patients and lumbar decompression has been used to treat the condition with variable success. Non operative measures have been investigated, but their success ranges from 15% to 43% in patients followed up for 1-5 years (Simotas in Clin Orthop 1(384):153-161, 2001). Salmon calcitonin injections have been investigated in previous trials and may have a treatment effect. Nasal salmon calcitonin has become available and if effective would have advantages over injections. Forty patients with symptoms of neurogenic claudication and MRI proven lumbar spinal stenosis were randomly assigned either nasal salmon calcitonin or placebo nasal spray to use for 4 weeks. This was followed by a 'washout' period of 6 weeks, and subsequent treatment with 6 weeks of nasal salmon calcitonin. Standard spine outcome measures including Oswestry disability index (ODI), low back outcome score, visual analogue score and shuttle walking test were administered at baseline, 4, 10 and 16 weeks. Twenty patients received nasal salmon calcitonin and twenty patients received placebo nasal spray. At 4 weeks post treatment there was no statistically significant difference in the outcome measures between the two groups. The change in ODI was a mean 1.3 points for the calcitonin group and 0.6 points for the placebo group (P = 0.51), the mean change in visual analogue score for leg pain was 10 mm in the calcitonin group and 0 mm in the placebo group (P = 0.51). There was no significant difference in walking distance between the two groups, with a mean improvement in walking distance of 21 m in the calcitonin group and 8 m in the placebo group (P = 0.78). At the end of the trial the ODI had improved by a mean of 3.7 points in the calcitonin group and 3.8 points in the placebo group (P = 0.44). This randomised placebo controlled trial has not shown any treatment effect in patients with lumbar spinal stenosis treated with nasal salmon calcitonin.

The effect of duration of symptoms on standard outcome measures in the surgical treatment of spinal stenosis

The effect of the duration of symptoms on the outcome of lumbar decompression surgery is not known. The aim of our study was to determine the predictors of functional outcome of lumbar decompression surgery for degenerative spinal stenosis with particular emphasis on the duration of symptoms. In this prospective cohort study, we recruited 100 patients with a full data set available at 1-year and 85% at 2-year follow-ups: 49 females and 51 males with an average age of 62 (range 52-82). The pre- and post-operative outcome measures were Oswestry disability index (ODI), low back outcome score (LBOS), pain visual analogue score (VAS), modified somatic perception (MSP) and modified Zung depression (MZD) score. Dural tear occurred in 14%, and there was one post-operative extra-dural heamatoma. Overall, the ODI improved from a pre-operative of 56 (+/-13) to a 1-year ODI of 40 (+/-22) and at 2-year ODI of 40 (+/-21). The VAS improved from an average of 8 to 5.2 at 1 year and 4.9 at 2 years. There was a statistical significant association between symptom duration and the change in ODI (P=0.007 at 1-year follow-up, P=0.001 at 2-year follow-up), LBOS (P=0.001 at 1-year follow-up, P<0.001 at 2-year follow-up) and VAS (P=0.003 at 1-year follow-up, P=0.001 at 2-year follow-up). Subgroup analyses showed that patients with symptom duration of less than 33 months had a more favourable result. In addition, the patients who rated the operation as excellent had a statistically significantly shorter duration of symptoms. We have not found a predictive value for age at operation, MSP or MZD. The number of levels of decompression and the different types of decompression surgery did not influence the surgical results. Our study indicates that the symptom duration of more than 33 months has a less favourable functional outcome.

The efficacy of corticosteroids in periradicular infiltration for chronic radicular pain: a randomized, double-blind, controlled trial

STUDY DESIGN

A randomized, double-blind controlled trial.

OBJECTIVES

To determine the treatment effect of corticosteroids in periradicular infiltration for chronic radicular pain. We also examined prognostic factors in relation to the outcome of the procedure.

SUMMARY OF BACKGROUND DATA

Various studies have examined the therapeutic value of periradicular infiltration using treatment agents consisting of local anesthetic and corticosteroids for radicular pain, secondary to lumbar disc herniation and spinal stenosis. There is currently no randomized trial to determine the efficacy of a single injection of corticosteroids for chronic radicular pain.

METHODS

Eligible patients with radicular pain who had unilateral symptoms who failed conservative management were randomized for a single injection with bupivacaine and methylprednisolone or bupivacaine only. Outcome measures included the Oswestry Disability Index, visual analogue score for back pain and leg pain, claudication walking distance, and the patient's subjective level of satisfaction of the outcome.

RESULTS

We recruited 43 patients in the bupivacaine and methylprednisolone group and 43 patients in the bupivacaine only group. The follow-up rate is 100%. Five patients had early termination of the trial for discectomy and further root block. There is no statistically significant difference in the outcome measures between the groups at 3 months (change of the Oswestry Disability Index [P = 0.68], change in visual analogue score [back pain, P = 0.68; leg pain, P = 0.94], change in walking distance [P = 0.7]). Duration of symptoms has a statistically significant negative association with the change in Oswestry Disability Index (P = 0.03).

CONCLUSION

Clinical improvement occurred in both groups of patients. Corticosteroids did not provide additional benefit.

Predictive value of the duration of sciatica for lumbar discectomy. A prospective cohort study

The optimum timing of lumbar discectomy for sciatica is imprecise. We have investigated a number of prognostic factors in relation to the outcome of radiculopathy after lumbar discectomy. We recruited 113 consecutive patients of whom 103 (91%) were followed up at one year. We found a significant association between the duration of radiculopathy and the changes in the Oswestry Disability Index score (p = 0.005) and the low back outcome score (p = 0.03). Improvement in pain was independent of all variables. Patients with an uncontained herniated disc had a shorter duration of symptoms and a better functional outcome than those with a contained herniation. Our study suggests that patients with sciatica for more than 12 months have a less favourable outcome. We detected no variation in the results for patients operated on in whom the duration of sciatica was less than 12 months.

Predictive value of the duration of sciatica for lumbar discectomy

The optimum timing of lumbar discectomy for sciatica is imprecise. We have investigated a number of prognostic factors in relation to the outcome of radiculopathy after lumbar discectomy. We recruited 113 consecutive patients of whom 103 (91%) were followed up at one year. We found a significant association between the duration of radiculopathy and the changes in the Oswestry Disability Index score (p = 0.005) and the low back outcome score (p = 0.03). Improvement in pain was independent of all variables. Patients with an uncontained herniated disc had a shorter duration of symptoms and a better functional outcome than those with a contained herniation.

Our study suggests that patients with sciatica for more than 12 months have a less favourable outcome. We detected no variation in the results for patients operated on in whom the duration of sciatica was less than 12 months.

Outcomes of a prospective cohort study on peri-radicular infiltration for radicular pain in patients with lumbar disc herniation and spinal stenosis

The purpose of this study was to assess the outcome of peri-radicular infiltration for radicular pain in patients with spinal stenosis and lumbar disc herniation (LDH). Patients with spinal stenosis ( n=62) or LDH ( n=55) who met our criteria received fluoroscopically guided peri-radicular infiltration of local anaesthetic and steroid at the site of documented pathology. All the patients were followed-up at 3 months. There was a statistically significant difference in the functional outcome between the spinal stenosis group and the LDH group. The mean change in the Oswestry disability index (ODI) score for the spinal stenosis group was 5.5% compared to 12% for the LDH group. The spinal stenosis group had a mean change in visual analogue scales (VAS) of 1.2 compared to 2 for the LDH group. The higher the modified somatic perception score, modified zung depression and age at injection, the less favourable the outcome. There was a significantly better response to peri-radicular infiltration for radicular pain in patients with LDH than the spinal stenosis. Our findings help us to provide a better information for future patients. We do not know if this is a treatment effect or natural history of the pathology, as this is a cohort study and not a randomised controlled trial.

The effect of age on the change in deformity after anterior débridement surgery for tuberculosis of the spine

STUDY DESIGN

This article evaluates how an immature spine responds to anterior débridement surgery (without bone grafting) for spinal tuberculosis during growth and development. Sixty-three patients were studied, 29 of whom were children aged 10 years or less at the time of surgery, whereas the remaining 34 subjects were adults. These patients were the subject of the Medical Research Council Working Party's prospective study, started in Hong Kong in the mid-1960s.

OBJECTIVES

To evaluate how an immature spine responds to débridement surgery for tuberculosis, during growth and development, to determine whether there are differences in the longitudinal pattern of deformity between children and adults, and to determine the influence of disproportionate spinal growth on the progression of deformity in children.

SUMMARY OF BACKGROUND DATA

All patients were followed prospectively for a mean period of 19.6 years after débridement surgery. The mean age at surgery for children (n = 29) was 4.3 years and for adults (n = 34) 35.3 years.

METHODS

The kyphos and deformity angles were measured from lateral spinal radiographs obtained at preoperative evaluation and postoperatively at 6 months, 1 year, 5 years, and at final follow-up evaluation using an electronic digitizer.

RESULTS

The results showed that the longitudinal pattern of changes in the mean kyphos and deformity angles in young children presented a picture slightly different from that in adults. The mean angles were increased at the 6-month and at 1-year evaluations after débridement surgery in both groups. Afterward, in children there was some spontaneous correction in these mean angles, whereas in adults these angles showed variation according to the site of lesion during the follow-up years. Statistical analysis according to the site of spinal lesion showed that in thoracic tuberculosis, there was an increase in kyphos and deformity angles at the 6-months postoperative evaluation (more in children than in adults). There were no significant changes in these angles from the 1-year to the final follow-up evaluations. In thoracolumbar tuberculosis, there were significant increases in kyphos and deformity angles at the 6-month postoperative evaluation, and thereafter adults did not show any significant change until final follow-up examination, whereas children showed a tendency toward spontaneous correction, although this finding was not statistically significant. In lumbar tuberculosis, there was an equal tendency toward spontaneous correction in children and adults from 1 postoperative year onward.

CONCLUSIONS

The authors could find no evidence of disproportionate posterior spinal growth, which has been suspected in the past to be a factor involved in contributing to progression of kyphotic deformity after anterior débridement surgery for spinal tuberculosis.

Surgical management of spinal tuberculosis in adults. Hong Kong operation compared with debridement surgery for short and long term outcome of deformity

Of 112 patients who were subjects of the Medical Research Council's prospective study, 105 (94%) were involved in a longitudinal study follow-up for a mean of 15.3 years postoperatively. Seventy-one patients had radical resection of the tuberculous lesion and bone grafting, and the remaining 34 were treated with debridement surgery at a mean age of 36.7 and 35.3 years, respectively. All these patients were aged 18 years or older at the time of surgery. The kyphosis and deformity angles were measured on lateral spinal radiographs using an electronic digitizer. The results can be summarized as follows: (1) Neurologic recovery in both radical and debridement surgical groups were equally good and no patient had pain two years after surgery. There was no incidence of reactivation or recurrence of tuberculosis in either surgical group. (2) At the six-month postoperative evaluation, patients who had radical surgery showed marginal correction in deformity, whereas those who were treated with debridement showed deterioration in both kyphosis and deformity angles. There was a statistically significant difference between the two surgical groups for the mean changes in kyphosis and deformity angles at the six-month postoperative evaluation compared with their preoperative evaluation. (3) The mean difference for kyphosis and deformity angles at final follow-up evaluation from the patients' six-month postoperative measurements were not statistically significantly different between the two surgical groups. (4) Forty percent of patients showed an improvement in deformity angle by 5 degrees or more after radical surgery at the six-months postoperative evaluation, whereas 53% of patients showed deterioration after debridement surgery. (5) All patients with tuberculosis of the lumbar spine treated with radical surgery had normal lordosis in the lumbar spine at final follow-up evaluation, compared with only 63% of patients after debridement surgery. Correction achieved after surgery at the six-month evaluation was practically maintained up to final follow-up evaluation. Radical resection and bone grafting provided better correction of deformity than did debridement surgery.

The effect of age on the change in deformity after radical resection and anterior arthrodesis for tuberculosis of the spine

We compared the long-term changes in spinal deformity after a radical operation for tuberculosis of the spine in thirty-three children who were ten years old or younger at the time of the operation with those of seventy-one adult patients who were at least eighteen years old at the time of the operation. The spinal deformity was measured with use of the angles of kyphosis and deformity as assessed on lateral spinal radiographs made preoperatively and postoperatively at six months, one year, and five years and at the most recent follow-up evaluation (at a mean of fifteen years). We detected no significant difference in the mean angles of kyphosis and deformity between the children and the adults postoperatively at any follow-up evaluation; thus, we found that growth of the posterior portion of the spine does not contribute to the progression of deformity after a radical anterior procedure. The children who had tuberculosis of the thoracic spine had much better correction than the adults at the six-month follow-up examination. This correction was maintained. However, there were no such differences in the correction of the deformity between the adults and the children who had tuberculosis of the thoracolumbar or the lumbar spine. Our findings clearly show that a short anterior spinal arthrodesis done at an early age was not associated with progression of deformity during growth and development in our patients. The longitudinal pattern of changes in deformity was similar in the children and the adults, and there was no evidence of disproportionate posterior spinal growth contributing to the progression of deformity after anterior spinal arthrodesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Longitudinal changes in spinal deformity after anterior spinal surgery for tuberculosis of the spine in adults. A comparative analysis between radical and debridement surgery

Of 112 patients who entered the Medical Research Council's prospective study on the surgical management of spinal tuberculosis, 105 were available for review at a mean follow-up of 15.3 years postoperatively. All these patients were age 18 years or more at the time of surgery. Seventy-one patients had radical surgery; the remaining 34 underwent debridement surgery. The longitudinal changes in spinal deformity were evaluated using kyphus and deformity angles from lateral spinal radiographs obtained at preoperative evaluation, postoperatively at 6 months, 1 year, and 5 years, and at final follow-up. The mean kyphos and deformity angles showed correction after radical surgery at 6 months' evaluation; thereafter there were minimal variations up to final follow-up. Those who underwent debridement surgery showed an increase in these angles at 6 months postoperative evaluation; thereafter there were practically no changes in thoracic and thoracolumbar tuberculosis, whereas in lumbar tuberculosis there was spontaneous correction from 1 year post-surgery onward. The changes in mean kyphos and deformity angles at 6 months postoperative evaluation from their preoperative values were significantly different between the two surgical groups, where radical surgery produced better correction. Thus, the choice of surgery--radical or debridement--is important in determining the fate of spinal deformity in the management of tuberculosis of the spine.

Spinal deformity after childhood surgery for tuberculosis of the spine. A comparison of radical surgery and debridement

We have reviewed 80 children who were involved in the Medical Research Council (UK) trial of surgical treatment for tuberculosis of the spine in Hong Kong. Radical surgery or debridement had been performed at mean ages of 7.6 years (n = 47) and 5.1 years (n = 33) respectively. The patients were followed up to skeletal maturity (mean 17 years). Spinal deformity was measured on lateral radiographs taken preoperatively, at six months, one year, five years and at final follow-up. Radical surgery and grafting produced a reduction in kyphos and deformity angles at six months; this correction was maintained during the growth period. By contrast, after debridement surgery there was an increase in deformity at six months, with a tendency to some spontaneous correction during the growth period. There were statistically significant differences between angles for the radical and debridement groups only at six months postoperatively, but the changes during later follow-up were similar in the radical and debridement groups. Our findings highlight the importance of the surgical correction of deformity, and provide no evidence to suggest that disproportionate posterior spinal growth contributes to progression of deformity after anterior spinal fusion in children.

Spinal deformity after childhood surgery for tuberculosis of the spine. A comparison of radical surgery and debridement

We have reviewed 80 children who were involved in the Medical Research Council (UK) trial of surgical treatment for tuberculosis of the spine in Hong Kong. Radical surgery or debridement had been performed at mean ages of 7.6 years (n = 47) and 5.1 years (n = 33) respectively. The patients were followed up to skeletal maturity (mean 17 years). Spinal deformity was measured on lateral radiographs taken preoperatively, at six months, one year, five years and at final follow-up. Radical surgery and grafting produced a reduction in kyphos and deformity angles at six months; this correction was maintained during the growth period. By contrast, after debridement surgery there was an increase in deformity at six months, with a tendency to some spontaneous correction during the growth period. There were statistically significant differences between angles for the radical and debridement groups only at six months postoperatively, but the changes during later follow-up were similar in the radical and debridement groups. Our findings highlight the importance of the surgical correction of deformity, and provide no evidence to suggest that disproportionate posterior spinal growth contributes to progression of deformity after anterior spinal fusion in children.

17-year prospective study of surgical management of spinal tuberculosis in children. Hong Kong operation compared with debridement surgery for short- and long-term outcome of deformity

A comparative analysis of the short and long-term results of two surgical procedures, radical excision or debridement, for the management of spinal tuberculosis in children is reported. Eighty children (47 treated with radical surgery and 33 with debridement) were prospectively studied and followed to maturity (mean follow-up, 17 years postoperatively). The kyphus and deformity angles were measured from lateral spinal radiographs using an electronic digitizer. The results can be summarized as follows: 1) Long-term clinical outcome of the two surgical procedures were equally good for recovery of neurologic deficit and relief of pain. There was no incidence of reactivation and/or recurrence of tuberculous lesion in either group; 2) The mean changes in kyphus and deformity angles at the 6-month postoperative evaluation compared to their preoperative value were significantly different for the two surgical groups. There was an overall correction in these angles after radical surgery, whereas there was a deterioration after debridement surgery; 3) There were no significant differences in the changes in kyphus or deformity angles at final follow-up from their 6-month postoperative measurements between the two surgical groups; 4) The majority of children (56%) showed an improvement in deformity angle of 5 degrees or more after radical surgery at the 6-month postoperative evaluation, whereas 69% of children showed deterioration after debridement surgery; 5) At final follow-up in lumbar tuberculosis, 60% of patients in the debridement group had 10 degrees or more kyphus angle, whereas only one patient in the radical group had a kyphotic lumbar spine due to graft failure.(ABSTRACT TRUNCATED AT 250 WORDS)