Joost J. van Middendorp

A clinical prediction rule for ambulation outcomes after traumatic spinal cord injury: a longitudinal cohort study

BACKGROUND Traumatic spinal cord injury is a serious disorder in which early prediction of ambulation is important to counsel patients and to plan rehabilitation. We developed a reliable, validated prediction rule to assess a patients chances of walking independently after such injury. METHODS We undertook a longitudinal cohort study of adult patients with traumatic spinal cord injury, with early (within the first 15 days after injury) and late (1-year follow-up) clinical examinations, who were admitted to one of 19 European centres between July, 2001, and June, 2008. A clinical prediction rule based on age and neurological variables was derived from the international standards for neurological classification of spinal cord injury with a multivariate logistic regression model. Primary outcome measure 1 year after injury was independent indoor walking based on the Spinal Cord Independence Measure. Model performances were quantified with respect to discrimination (area under receiver-operating-characteristics curve [AUC]). Temporal validation was done in a second group of patients from July, 2008, to December, 2009. FINDINGS Of 1442 patients with spinal cord injury, 492 had available outcome measures. A combination of age (<65 vs ≥65 years), motor scores of the quadriceps femoris (L3), gastrocsoleus (S1) muscles, and light touch sensation of dermatomes L3 and S1 showed excellent discrimination in distinguishing independent walkers from dependent walkers and non-walkers (AUC 0·956, 95% CI 0·936-0·976, p<0·0001). Temporal validation in 99 patients confirmed excellent discriminating ability of the prediction rule (AUC 0·967, 0·939-0·995, p<0·0001). INTERPRETATION Our prediction rule, including age and four neurological tests, can give an early prognosis of an individuals ability to walk after traumatic spinal cord injury, which can be used to set rehabilitation goals and might improve the ability to stratify patients in interventional trials. FUNDING Internationale Stiftung für Forschung in Paraplegie.

A methodological systematic review on surgical site infections following spinal surgery: part 1: risk factors.

Study Design. A methodological systematic review. Objective. To critically appraise the validity of risk factors for surgical site infection (SSI) after spinal surgery. Summary of Background Data. SSIs lead to higher morbidity, mortality, and increased health care costs. Understanding which factors lead to an increased risk of SSI is important for the development of prophylactic protocols to counter this risk. To date, however, no review appraising the methodological quality of studies evaluating risk factors for spinal SSIs has been published. Methods. Contemporary studies identifying risk factors for SSI after spinal surgery were searched through the Medline and EMBASE databases (January 2001 to December 2010). References were retrieved and bias-prone study features were abstracted individually and independently by 2 authors. Results. Twenty-four eligible studies were identified, including 9 (nested) case-control studies and 15 case series. Included studies covered wide variations of indications and surgical procedures. A total of 73 different types of factors were evaluated for the risk of an SSI of which 34 (47%) were reported to be significantly related to at least 1 study. Only the following risk factors—diabetes mellitus, obesity, and previous SSI—were confirmed more often (n = 11, 8, and 3, respectively) as a significant risk factor for an SSI than they were disproved (n = 7, 6, and 1, respectively). Various sources of heterogeneity were observed, including patient selection, selection and analysis of putative risk factors, and definitions of SSI outcomes. Conclusion. There is an abundance of conflicting data on risk factors for SSI after spinal surgery. Given various sources of heterogeneity observed in observational literature, there is a paucity of solid evidence for the proof of robust risk factors. The authors recommend the introduction, validation, and use of a standardized set of strongly justified eligibility criteria and well-defined candidate risk factors and spinal SSI outcomes.

Lower-limb exoskeletons for individuals with chronic spinal cord injury: findings from a feasibility study

Objective: To assess the feasibility of conducting a well-powered trial evaluating the neurological and functional effects of using an exoskeleton in individuals with chronic spinal cord injury. Design: A longitudinal, prospective, self-controlled feasibility study. Setting: Specialist Spinal Cord Injuries Centre, UK; 8 months during 2013–2014. Subjects: Individuals with chronic motor complete or incomplete spinal cord injury. Interventions: Enrolled subjects were assigned to 20 exoskeleton (ReWalk™, Argo Medical Technologies Ltd, Yokneam Ilit, Israel) training sessions over a 10-week training period. Main measures: Feasibility measures, clinical and mobility outcome measures and measures appraising subjects’ disability and attitude towards assistive technology were assessed before, during and after the study. Descriptive statistics were applied. Results: Out of 60 candidates, ten (17%) were enrolled and five (8%) completed the training programme. Primary reasons for not enrolling were ineligibility (n = 24, 40%) and limited interest to engage in a 10-week training programme (n = 16, 27%). Five out of ten enrolled subjects experienced grade I/II skin aberrations. While walking speeds were higher and walking distances were longer in all exoskeleton users when compared with non-use, the exoskeleton did generally not meet subjects’ high expectations in terms of perceived benefits. Conclusions: The conduct of a controlled trial evaluating the benefits of using exoskeletons that require a lengthy user-commitment to training of individuals with chronic motor complete or incomplete spinal cord injury comes with considerable feasibility challenges. Vigilance is required for preventing and detecting medical complications in spinal cord injury exoskeleton users.

What should an ideal spinal injury classification system consist of? A methodological review and conceptual proposal for future classifications.

Since Böhler published the first categorization of spinal injuries based on plain radiographic examinations in 1929, numerous classifications have been proposed. Despite all these efforts, however, only a few have been tested for reliability and validity. This methodological, conceptual review summarizes that a spinal injury classification system should be clinically relevant, reliable and accurate. The clinical relevance of a classification is directly related to its content validity. The ideal content of a spinal injury classification should only include injury characteristics of the vertebral column, is primarily based on the increasingly routinely performed CT imaging, and is clearly distinctive from severity scales and treatment algorithms. Clearly defined observation and conversion criteria are crucial determinants of classification systems’ reliability and accuracy. Ideally, two principle spinal injury characteristics should be easy to discern on diagnostic images: the specific location and morphology of the injured spinal structure. Given the current evidence and diagnostic imaging technology, descriptions of the mechanisms of injury and ligamentous injury should not be included in a spinal injury classification. The presence of concomitant neurologic deficits can be integrated in a spinal injury severity scale, which in turn can be considered in a spinal injury treatment algorithm. Ideally, a validation pathway of a spinal injury classification system should be completed prior to its clinical and scientific implementation. This review provides a methodological concept which might be considered prior to the synthesis of new or modified spinal injury classifications.

Incidence of and risk factors for complications associated with halo-vest immobilization: a prospective, descriptive cohort study of 239 patients.

BACKGROUND Since high rates of serious complications, such as death and pneumonia, during halo-vest immobilization have been reported, there has been a tendency of restraint with regard to the use of the halo vest. However, the rate of complications in a high-volume center with sufficient experience is unknown. Our objective was to determine the incidence of and risk factors associated with complications during halo-vest immobilization. METHODS During a five-year period, a prospective cohort study was performed in a single, level-I trauma center that was also a tertiary referral center for spinal disorders. Data from all patients undergoing halo-vest immobilization were collected prospectively, and every complication was recorded. The primary outcome was the presence or absence of complications. Univariate regression analysis and regression modeling were used to analyze the results. RESULTS In 239 patients treated with halo-vest immobilization, twenty-six major, seventy-two intermediate, and 121 minor complications were observed. Fourteen patients (6%) died during the treatment, although only one death was related directly to the immobilization and three were possibly related directly to the immobilization. Twelve patients (5%) acquired pneumonia during halo-vest immobilization. Patients older than sixty-five years did not have an increased risk of pneumonia (p = 0.543) or halo vest-related mortality (p = 0.467). Halo vest-related complications ranged from three patients (1%) with incorrect initial placement of the halo vest to twenty-nine patients (12%) with a pin-site infection. Pin-site infection was significantly related to pin penetration through the outer table of the skull (odds ratio, 4.34; 95% confidence interval, 1.22 to 15.51; p = 0.024). In 164 trauma patients treated only with halo-vest immobilization, cervical fractures with facet joint involvement or dislocations were significantly related to radiographic loss of alignment during follow-up (odds ratio, 2.81; 95% confidence interval, 1.06 to 7.44; p = 0.031). CONCLUSIONS There are relatively low rates of mortality and pneumonia during halo-vest immobilization, and elderly patients do not have an increased risk of pneumonia or death related to halo-vest immobilization. Nevertheless, the total number of minor complications is substantial. This study confirms that awareness of and responsiveness to minor complications can prevent subsequent development of serious morbidities and perhaps reduce mortality.

The Edwin Smith papyrus: a clinical reappraisal of the oldest known document on spinal injuries.

Dating from the seventeenth century b.c. the Edwin Smith papyrus is a unique treatise containing the oldest known descriptions of signs and symptoms of injuries of the spinal column and spinal cord. Based on a recent “medically based translation” of the Smith papyrus, its enclosed treasures in diagnostic, prognostic and therapeutic reasoning are revisited. Although patient demographics, diagnostic techniques and therapeutic options considerably changed over time, the documented rationale on spinal injuries can still be regarded as the state-of-the-art reasoning for modern clinical practice.

Methodological Systematic Review : Mortality in Elderly Patients With Cervical Spine Injury : A Critical Appraisal of the Reporting of Baseline Characteristics, Follow-up, Cause of Death, and Analysis of Risk Factors

Study Design. Methodologic systematic review. Objective. To determine the validity of reported risk factors for mortality in elderly patients with cervical spine injury. Summary of Background Data. In elderly patients with cervical spine injury, mortality has frequently been associated with the type of treatment. To date, however, no review evaluating the validity of reported risk factors for mortality in elderly patients with cervical spine injury has been published. Methods. Studies evaluating the treatment of cervical spine injuries in elderly (≥60 years of age) patients were searched through the Medline and EMBASE databases. In addition to standard methodologic details, reporting of putative confounding baseline characteristics and analysis of risk factors for mortality were appraised critically. For this purpose, patient data presented in included studies were pooled. Exploratory descriptive statistics were used for data analysis. Results. Twenty-six eligible studies were identified, including a total of 1550 pooled elderly subjects. Except for 2, all studies reported presence or absence of spinal cord injury. Details concerning the severity and/or extent of the injury were reported in 12 (46%) studies. Pre-existing comorbidities were reported in 9 studies (35%). In the pooled subjects, the cause of death was not reported in 155 of 335 deceased patients (42%). Based on own results, 18 (69%) studies reported on risk factors for mortality. Of these studies, 6 (23%) performed statistical analyses of risk factors for mortality outcomes. Only 1 study statistically adjusted potential risk factors for mortality for confounding. Conclusion. Overall, pre-existing comorbidities, concomitant injuries, follow-up and cause of death have been underreported in studies investigating the treatment of cervical spine injuries in elderly patients. To strengthen the validity of risk factors for mortality in future clinical trials, adjustments for appropriately reported putative confounders by regression analysis are mandatory.

Diagnosis and Prognosis of Traumatic Spinal Cord Injury

Despite promising advances in basic spinal cord repair research, no effective therapy resulting in major neurological or functional recovery after traumatic spinal cord injury (tSCI) is available to date. The neurological examination according to the International Standards for Neurological and Functional Classification of Spinal Cord Injury Patients (International Standards) has become the cornerstone in the assessment of the severity and level of the injury. Based on parameters from the International Standards, physicians are able to inform patients about the predicted long-term outcomes, including the ability to walk, with high accuracy. In those patients who cannot participate in a reliable physical neurological examination, magnetic resonance imaging and electrophysiological examinations may provide useful diagnostic and prognostic information. As clinical research on this topic continues, the prognostic value of the reviewed diagnostic assessments will become more accurate in the near future. These advances will provide useful information for physicians to counsel tSCI patients and their families during the catastrophic initial phase after the injury.

Malignant cord compression: A critical appraisal of prognostic factors predicting functional outcome after surgical treatment

Objectives: Advanced tumor disease and metastatic spinal cord compression (MSCC) are two entities with a high impact on patients’ quality of life. However, prognostic factors on the outcome after primary decompressive surgery are less well-defined and not yet standardized. The aim of this review was to identify prognostic variables that predict functional or ambulatory outcomes in surgically treated patients with symptomatic MSCC. Materials and Methods: We conducted MEDLINE database searches using relevant keywords in order to identify abstracts referring to prognostic factors on ambulatory outcomes in surgically treated MSCC patients. Details of all selected articles were assembled and the rates of ambulation were stratified. Results: Evidence from five retrospective comparative trials and one observational prospective study summarizes different prognostic factors with a positive or negative influence on postoperative ambulatory status. Ambulatory patients maintaining ambulation status after decompression of the spinal cord constituted 62.1%. The overall rate of MSCC patients losing the ability to ambulate was 7.5% compared to 23.5 % who regained ambulation. Preoperative ambulation status, time to surgery, compression fracture and individual health status seem to be the most relevant prognostic factors for ambulatory outcome. Conclusions: There is a lack of standardized prognostic tools which allow predicting outcome in surgically treated patients. A quantitative score consisting of reliable prognostic tools is essential to predict loss and/or regain of ambulation and requires validation in future prospective clinical trials.

Top ten research priorities for spinal cord injury

In the Edwin Smith papyrus—the oldest known surviving text about management of traumatic injuries— injuries to the spinal cord were considered to be “a medical condition that cannot be healed.’’ Although more than 3000 years later a cure for spinal cord injury has not yet been identifi ed, research into the diagnosis, prognosis, and treatment of spinal cord injury, and its wide range of secondary sequelae has intensifi ed in the past few decades. Nonetheless, to our knowledge, no systematic appraisal of patients’, carers’ and health-care professionals’ preferred research questions into spinal cord has been done to date. In collaboration with the James Lind Alliance, a UK National Institute for Health Research-supported organ isation that aims to identify gaps in scientifi c, medical, and psychosocial knowledge that matter most to patients, carers, and health professionals, we completed a multidisciplinary priority setting partnership that has defi ned a British research agenda for spinal cord injury for the next 5–10 years. There are as yet, no plans to monitor progress. Our priority setting process involved four key stages: (1) collecting research questions, (2) checking of existing research evidence through systematic searches of the literature by the project data manager, (3) interim prioritisation, and (4) a fi nal consensus meeting to reach agreement about the top ten research priorities. We invited individuals with spinal cord dysfunction due to trauma and non-traumatic causes, including trans verse myelitis and those with cauda equina syndrome (henceforth grouped and referred to as individuals with spinal cord injury), to participate in this priority setting partnership. Additionally, we encouraged caregivers and healthcare professionals with an interest in spinal cord injury to participate. In view of the highly specialist nature of spinal cord injury in children, no questions addressing paediatric injury were considered. We obtained 784 questions from 403 survey respondents (290 individuals with spinal cord injury) which, after merging of duplicate questions and checking of systematic reviews for evidence, were reduced to 109 unique unanswered research questions. A total of 293 people (211 individuals with spinal cord injury) participated in the interim prioritisation process, leading to the identifi cation of 25 shared top priorities. At a fi nal consensus meeting, a group of individuals with spinal cord injury, carers, and health professionals agreed their top ten priorities for future research (panel). Whilst the call for stem-cell research into spinal cord injury resonated with the people involved in this partnership, nine other research priorities show that spinal cord injury research should involve much more than presently meets the public eye. This research agenda for spinal cord injury has been defi ned by people to whom it matters most, and should now inform the scope and future activities of funders and researchers alike.