Sacral sparing in SCI: beyond the S4-S5 and anorectal examination

Prediction of early bladder outcomes after spinal cord injury: The HALT score

AIMS

Neurogenic bladder (NB) is a prevalent and debilitating consequence of spinal cord injury (SCI). Indeed, the accurate prognostication of early bladder outcomes is crucial for patient counseling, rehabilitation goal setting, and personalized intervention planning.

METHODS

A retrospective exploratory analysis was conducted on a cohort of consecutive SCI patients admitted to a rehabilitation facility in China from May 2016 to December 2022. Demographic, clinical, and electrophysiological data were collected within 40 days post-SCI, with bladder outcomes assessed at 3 months following SCI onset.

RESULTS

The present study enrolled 202 SCI patients with a mean age of 40.3 ± 12.3 years. At 3 months post-SCI, 79 participants exhibited complete bladder emptying. Least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression analyses identified the H-reflex of the soleus muscle, the American Spinal Injury Association Lower Extremity Motor Score (ASIA-LEMS), and the time from lesion to rehabilitation facility (TLRF) as significant independent predictors for bladder emptying. A scoring system named HALT was developed, yielding a strong discriminatory performance with an area under the receiver operating characteristics curve (aROC) of 0.878 (95% CI: 0.823-0.933). A simplified model utilizing only the H-reflex exhibited excellent discriminatory ability with an aROC of 0.824 (95% CI: 0.766-0.881). Both models demonstrated good calibration via the Hosmer-Lemeshow test and favorable clinical net benefits through decision curve analysis (DCA). In comparison to ASIA-LEMS, both the HALT score and H-reflex showed superior predictive accuracy for bladder outcome. Notably, in individuals with incomplete injuries, the HALT score (aROC = 0.973, 95% CI: 0.940-1.000) and the H-reflex (aROC = 0.888, 95% CI: 0.807-0.970) displayed enhanced performance.

CONCLUSION

Two reliable models, the HALT score and the H-reflex, were developed to predict bladder outcomes as early as 3 months after SCI onset. Importantly, this study provides hitherto undocumented evidence regarding the predictive significance of the soleus H-reflex in relation to bladder outcomes in SCI patients.

A Single Dermatome Clinical Prediction Rule for Independent Walking 1 Year After Spinal Cord Injury

OBJECTIVE

To derive and validate a simple, accurate CPR to predict future independent walking ability after SCI at the bedside that does not rely on motor scores and is predictive for those initially classified in the middle of the SCI severity spectrum.

DESIGN

Retrospective cohort study. Binary variables were derived, indicating degrees of sensation to evaluate predictive value of pinprick and light touch variables across dermatomes. The optimal single sensory modality and dermatome was used to derive our CPR, which was validated on an independent dataset.

SETTING

Analysis of SCI Model Systems dataset.

PARTICIPANTS

Individuals with traumatic SCI. The data of 3679 participants (N=3679) were included with 623 participants comprising the derivation dataset and 3056 comprising the validation dataset.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Self-reported ability to walk both indoors and outdoors.

RESULTS

Pinprick testing at S1 over lateral heels, within 31 days of SCI, accurately identified future independent walkers 1 year after SCI. Normal pinprick in both lateral heels provided good prognosis, any pinprick sensation in either lateral heel provided fair prognosis, and no sensation provided poor prognosis. This CPR performed satisfactorily in the middle SCI severity subgroup.

CONCLUSIONS

In this large multi-site study, we derived and validated a simple, accurate CPR using only pinprick sensory testing at lateral heels that predicts future independent walking after SCI.

Pathophysiology, Classification and Comorbidities after Traumatic Spinal Cord Injury

The spinal cord is a conduit within the central nervous system (CNS) that provides ongoing communication between the brain and the rest of the body, conveying complex sensory and motor information necessary for safety, movement, reflexes, and optimization of autonomic function. After a spinal cord injury (SCI), supraspinal influences on the spinal segmental control system and autonomic nervous system (ANS) are disrupted, leading to spastic paralysis, pain and dysesthesia, sympathetic blunting and parasympathetic dominance resulting in cardiac dysrhythmias, systemic hypotension, bronchoconstriction, copious respiratory secretions and uncontrolled bowel, bladder, and sexual dysfunction. This article outlines the pathophysiology of traumatic SCI, current and emerging methods of classification, and its influence on sensory/motor function, and introduces the probable comorbidities associated with SCI that will be discussed in more detail in the accompanying manuscripts of this special issue.

Adaptação transcultural para o Português do questionário de autorrelato da função sensorial e motora de S4-5 (S4-5Q) em pessoas com lesão medular espinhal

Objective  The “Self-report S4-5 sensory and motor function questionnaire (S4-5Q)” is a short questionnaire that aims to assess the function of the sacral segments, S4 and S5, after a spinal cord injury (SCI), with the purpose of replacing the rectal exam test. The aim of the present study was to carry out a cross-cultural adaptation of the S4-5Q to the Brazilian Portuguese language and to investigate the test-retest reliability of this version.

Method  The translation and cross-cultural adaptation was performed using the methodology of translation and backtranslation. Initially, translations were done by three independent translators. Their synthesis was then submitted to an expert committee for analysis (SCI health professionals); then, the backtranslation to the original language was sent to the original author and, after all the adjustments, the final version was completed. For test-retest reliability, 24 individuals with chronic SCI were recruited (2 evaluations with an interval of 7 to 14 days between them). Statistical analysis was performed using IBM-SPSS (Version 20, SPSS Inc, Chicago, IL, USA) with data pretabulated in Microsoft Excel (Microsoft Corporation, Redmond, WA, USA). Reliability was tested with Cohen Kappa, and internal consistency with Cronbach α, both adopting p  < 0.05 as significant.

Results  In the reliability analysis, the results of all questions showed almost perfect agreement (Kappa > 0.81) and good internal consistency (Cronbach α: 0.65–0.77) between the questions and final classification.

Conclusion  The cross-culturally adapted S4-5Q is reliable to be applied to the Brazilian population with chronic SCI to determine their S4-5 sensory and motor function.

Reliability of S3 pressure sensation and voluntary hip adduction/toe flexion and agreement with deep anal pressure and voluntary anal contraction in classifying persons with traumatic spinal cord injury

Context/Objective: The sacral examination components of the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI), namely deep anal pressure (DAP) and voluntary anal sphincter contraction (VAC), are often difficult to perform. We evaluated whether pressure sensation at the S3 dermatome (S3P), and voluntary hip adductor or toe flexor contraction (VHTC) are tenable alternatives. Here we report test-retest reliability and agreement of these components at 1 month after spinal cord injury (SCI), and impact of disagreement on American Spinal Injury Association (ASIA) Impairment Scale (AIS) grades. Design: Longitudinal cohort. ISNCSCI examination, S3P and VHTC conducted at 1-month post-injury; retest of the sacral exam, S3P and VHTC within 3 days. Follow-up examinations performed at 3, 6, and 12 months. Setting: Five Spinal Cord Injury Model System Centers. Participants: Subjects with acute traumatic SCI, neurological levels T12 and above, AIS grades A-C. Interventions: None. Outcome Measures: ISNCSCI exam, AIS grades. Results: Fifty-one subjects had 1-month data, and 39 had at least one follow-up examination. Test-retest reliability indicated perfect agreement (kappa = 1.0) for all data except S3P (kappa = 0.96). The agreement was almost perfect between S3P and DAP (kappa = 0.84) and between VHTC and VAC (kappa = 0.81). VHTC and VAC differed more often with neurologic levels below T10, possibly due to root escape in conus medullaris injuries. Conclusion: S3P and VHTC show promise as alternatives to DAP and VAC for determining sacral sparing in persons with neurologic levels T10 and above. Reliability and agreement should be evaluated at earlier timepoints and in children with SCI.

An interview based approach to the anorectal portion of the International Standards of Neurological Classification of Spinal Cord Injury Exam (I-A-ISNCSCI): a pilot study

STUDY DESIGN

Prospective, single-blinded study.

OBJECTIVE

To design and evaluate the use of an interview based version of the anorectal portion of the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) exam in the acute inpatient rehabilitation (AIR) setting.

SETTING

AIR unit.

METHODS

Participants admitted to AIR underwent standard ISNCSCI exams (S-ISNCSCI) as part of routine inpatient care within 3 days of being administered an interview version of the anorectal portion of the ISNCSCI (I-A-ISNCSCI). Agreement between the anorectal portion of the S-ISNCSCI (S-A-ISNCSCI) and the I-A-ISNCSCI was evaluated.

RESULTS

Forty of forty-five enrolled participants completed the assessments. Agreement between the I-A-ISNCSCI and S-A-ISNCSCI was substantial for anorectal sensation to light touch (k = 0.71, 95% CI 0.52-0.90, N = 36), pin prick (k = 0.68, 95% CI 0.48-0.87, N = 38), deep anal pressure (k = 0.77, 95% CI 0.53-1.00, N = 37), and completeness of injury based on combined sacral sensory criteria (k = 0.72, 95% CI 0.47-0.97, N = 40); and fair for voluntary anal contraction (k = 0.29, 95% CI -0.01 to 0.59, N = 36). Responses of "I don't know" were excluded from agreement analyses.

CONCLUSIONS

This pilot study was a first step in developing interview based tools such as the I-A-ISNCSCI in an AIR setting providing convenient access to individuals with SCI and their direct feedback. The study design introduces potential recall bias and may not match true clinical situations such as remote follow-up of neurological changes for chronic patients. The use of interview based tools for assessing individuals with SCI remains worthy of further study.

Bowel Outcome Prediction After Traumatic Spinal Cord Injury: Longitudinal Cohort Study

Background. Predicting functional outcomes after traumatic spinal cord injury (SCI) is essential for counseling, rehabilitation planning, and discharge. Moreover, the outcome prognosis is crucial for patient stratification when designing clinical trials. However, no valid prediction rule is currently available for bowel outcomes after a SCI. Objective. To generate a model for predicting the achievement of independent, reliable bowel management at 1 year after traumatic SCI. Methods. We performed multivariable logistic regression analyses of data for 1250 patients with traumatic SCIs that were included in the European Multicenter Study about Spinal Cord Injury. The resulting model was prospectively validated on data for 186 patients. As potential predictors, we evaluated age, sex, and variables from the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) and the Spinal Cord Independence Measure (SCIM), measured within 40 days of the injury. A positive outcome at 1 year post-SCI was assessed with item 7 of the SCIM. Results. The model relied on a single predictor, the ISNCSCI total motor score—that is, the sum of muscle strengths in 5 key muscle groups in each limb. The area under the receiver operating characteristics curve (aROC) was 0.837 (95% CI: 0.815-0.859). The prospective validation confirmed high predictive power: aROC = 0.817 (95% CI: 0.754-0.881). Conclusions. We generated a valid model for predicting independent, reliable bowel management at 1 year after traumatic SCI. Its application could improve counseling, optimize patient-tailored rehabilitation planning, and become crucial for appropriate patient stratification in future clinical trials.

Clinical associations with telomere length in chronic spinal cord injury

STUDY DESIGN

Cross-sectional study OBJECTIVES: To determine clinical factors associated with telomere length in persons with chronic spinal cord injury (SCI).

SETTING

Veterans Affairs Medical Center, Boston, MA.

METHODS

Two hundred seventy-eight participants with chronic SCI provided blood samples for measurement of C-reactive protein (CRP), interleukin-6 (IL-6), and telomere length, completed respiratory health questionnaires, underwent dual X-ray absorptiometry (DXA) to assess body fat, and completed spirometry. High-throughput real-time PCR assays were used to assess telomere length in leukocyte genomic DNA. Linear regression models were used to assess cross-sectional associations with telomere length.

RESULTS

Telomere length was inversely related to age (p < 0.0001). In age-adjusted models, gender, race, injury duration, %-total and %-trunk fat, body mass index (BMI), %-predicted forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV₁), chronic cough or phlegm, CRP, IL-6, wheeze, smoking, diabetes, heart disease, chronic obstructive pulmonary disease (COPD), skin ulcer, urinary tract infection (UTI), or chest illness history were not significantly associated with telomere length. There was a suggestive age-adjusted association between persons with the most severe SCI (cervical motor complete and AIS C) and shorter telomere length (p = 0.055), an effect equivalent to ~8.4 years of premature aging. There were similar age-adjusted associations with telomere length between persons using a wheelchair (p = 0.059) and persons with chronic urinary catheter use (p = 0.082) compared to persons without these characteristics.

CONCLUSIONS

Our results suggest that clinical characteristics such as decreased mobility and bladder dysfunction that are common in individuals with more severe SCI are associated with shorter telomere length.

Pulse article: How do you do the international standards for neurological classification of SCI anorectal exam?

STUDY DESIGN

Online survey of spinal cord injury (SCI) practitioners.

OBJECTIVES

Determine provider understanding and routine performance of International Standards for Neurologic Classification of Spinal Cord Injury (ISNCSCI) anorectal examination.

SETTING

International online questionnaire.

METHODS

A descriptive survey was developed to assess current performance of the ISNCSCI anorectal exam. Information about this survey was disseminated through social email and international societies between the months of March and April 2017.

RESULTS

Two hundred and fifteen SCI practitioners completed the survey. Of these, 157 (73%) were specialists in physical medicine and rehabilitation, 32 (15%) were physical therapists, 6 were neurologists, 6 were orthopedists, and 3 were neurosurgeons. Of responders, 90% routinely personally performed the anal exam of the ISNCSCI, of whom, 42 placed firm pressure against the anal sphincter, 58 placed firm pressure against the rectal wall, and 87 placed firm pressure against the anal sphincter and rectal wall as part of the exam. On a routine basis, 74% tested sensation at the junction of the anal sphincter and skin, 82% had the patient attempt to squeeze their finger, and 50% performed the bulbocavernosus reflex.

CONCLUSIONS

Marked inconsistency exists in the performance of the ISNCSCI anal examination. Researchers and clinicians need more education about the performance of the examination. Consideration should be given for the components of deep rectal sensation and anal pressure to be separately documented in the neurologic exam and for researchers to focus separately on recovery of sacral function vs. ambulatory function in clinical trials.

Spinal Cord Injury Clinical Registries: Improving Care across the SCI Care Continuum by Identifying Knowledge Gaps

Timely access and ongoing delivery of care and therapeutic interventions is needed to maximize recovery and function after traumatic spinal cord injury (tSCI). To ensure these decisions are evidence-based, access to consistent, reliable, and valid sources of clinical data is required. The Access to Care and Timing Model used data from the Rick Hansen SCI Registry (RHSCIR) to generate a simulation of healthcare delivery for persons after tSCI and to test scenarios aimed at improving outcomes and reducing the economic burden of SCI. Through model development, we identified knowledge gaps and challenges in the literature and current health outcomes data collection throughout the continuum of SCI care. The objectives of this article were to describe these gaps and to provide recommendations for bridging them. Accurate information on injury severity after tSCI was hindered by difficulties in conducting neurological assessments and classifications of SCI (e.g., timing), variations in reporting, and the lack of a validated SCI-specific measure of associated injuries. There was also limited availability of reliable data on patient factors such as multi-morbidity and patient-reported measures. Knowledge gaps related to structures (e.g., protocols) and processes (e.g., costs) at each phase of care have prevented comprehensive evaluation of system performance. Addressing these knowledge gaps will enhance comparative and cost-effectiveness evaluations to inform decision-making and standards of care. Recommendations to do so were: standardize data element collection and facilitate database linkages, validate and adopt more outcome measures for SCI, and increase opportunities for collaborations with stakeholders from diverse backgrounds.

Development and validation of a bowel-routine-based self-report questionnaire for sacral sparing after spinal cord injury

STUDY DESIGN

An observational study.

OBJECTIVE

To develop a self-administered tool for assessment of sacral sparing after spinal cord injury (SCI) and to test its validity in individuals with SCI.

SETTING

Peking University Third Hospital, Beijing, China.

METHODS

A 5-item SCI sacral sparing self-report questionnaire was developed based on several events that most patients might experience during bowel routine. 102 participants who sustained SCI within 12 months were asked to complete the questionnaire followed by an anorectal examination. Agreements of answers to the questionnaire and the physical examination were analyzed. Sensitivity, specificity and Youden's index of each item was calculated.

RESULTS

The first four questions regarding the S4-5 sensation including deep anal pressure showed high agreement with the results of the physical examination (κ: 0.79-0.93). Sensitivity, specificity and Youden's index were also high (all above 80%). For the fifth question related to the voluntary anal contraction, the agreement was almost perfect with good sensitivity and specificity among patients without increased anal sphincter tone (AST). In patients with increased AST, the agreement was fair.

CONCLUSION

The validity of this questionnaire for the assessment of sacral sparing in up to 12 months post injury is good except for the motor function when there was increased AST. In some situations it could be considered as an alternative tool for digital rectal examination, especially when repeated examinations are not feasible. It is suggested that change of sacral sparing may be detected by the questionnaire.

A novel approach for assigning levels to monkey and human lumbosacral spinal cord based on ventral horn morphology

Proper identification of spinal cord levels is crucial for clinical-pathological and imaging studies in humans, but can be a challenge given technical limitations. We have previously demonstrated in non-primate models that the contours of the spinal ventral horn are determined by the position of motoneuron pools. These positions are preserved within and among individuals and can be used to identify lumbosacral spinal levels. Here we tested the hypothesis that this approach can be extended to identify monkey and human spinal levels. In 7 rhesus monkeys, we retrogradely labeled motoneuron pools that represent rostral, middle and caudal landmarks of the lumbosacral enlargement. We then aligned the lumbosacral enlargements among animals using absolute length, segmental level or a relative scale based upon rostral and caudal landmarks. Inter-animal matching of labeled motoneurons across the lumbosacral enlargement was most precise when using internal landmarks. We then reconstructed 3 human lumbosacral spinal cords, and aligned these based upon homologous internal landmarks. Changes in shape of the ventral horn were consistent among human subjects using this relative scale, despite marked differences in absolute length or age. These data suggest that the relative position of spinal motoneuron pools is conserved across species, including primates. Therefore, in clinical-pathological or imaging studies in humans, one can assign spinal cord levels to even single sections by matching ventral horn shape to standardized series.

Prediction of Bladder Outcomes after Traumatic Spinal Cord Injury: A Longitudinal Cohort Study

BACKGROUND

Neurogenic bladder dysfunction represents one of the most common and devastating sequelae of traumatic spinal cord injury (SCI). As early prediction of bladder outcomes is essential to counsel patients and to plan neurourological management, we aimed to develop and validate a model to predict urinary continence and complete bladder emptying 1 y after traumatic SCI.

METHODS AND FINDINGS

Using multivariate logistic regression analysis from the data of 1,250 patients with traumatic SCI included in the European Multicenter Spinal Cord Injury study, we developed two prediction models of urinary continence and complete bladder emptying 1 y after traumatic SCI and performed an external validation in 111 patients. As predictors, we evaluated age, gender, and all variables of the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) and of the Spinal Cord Independence Measure (SCIM). Urinary continence and complete bladder emptying 1 y after SCI were assessed through item 6 of SCIM. The full model relies on lower extremity motor score (LEMS), light-touch sensation in the S3 dermatome of ISNCSI, and SCIM subscale respiration and sphincter management: the area under the receiver operating characteristics curve (aROC) was 0.936 (95% confidence interval [CI]: 0.922-0.951). The simplified model is based on LEMS only: the aROC was 0.912 (95% CI: 0.895-0.930). External validation of the full and simplified models confirmed the excellent predictive power: the aROCs were 0.965 (95% CI: 0.934-0.996) and 0.972 (95% CI 0.943-0.999), respectively. This study is limited by the substantial number of patients with a missing 1-y outcome and by differences between derivation and validation cohort.

CONCLUSIONS

Our study provides two simple and reliable models to predict urinary continence and complete bladder emptying 1 y after traumatic SCI. Early prediction of bladder function might optimize counselling and patient-tailored rehabilitative interventions and improve patient stratification in future clinical trials.

Patterns of Sacral Sparing Components on Neurologic Recovery in Newly Injured Persons With Traumatic Spinal Cord Injury

OBJECTIVE

To assess the patterns of sacral sparing and recovery in newly injured persons with traumatic spinal cord injury (SCI).

DESIGN

Retrospective analysis of data from the national Spinal Cord Injury Model Systems (SCIMS) database for patients enrolled from January 2011 to February 2015.

SETTING

SCIMS centers.

PARTICIPANTS

Individuals (N=1738; age ≥16y) with traumatic SCI admitted to rehabilitation within 30 days after injury with follow-up at discharge, at 1 year, or both.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

International Standards for Neurological Classification of Spinal Cord Injury examination results at admission and follow-up (discharge or 1y, or both).

RESULTS

Conversion from an initial American Spinal Injury Association Impairment Scale (AIS) grade A to incomplete status was 20% at rehabilitation discharge and 27.8% at 1 year, and was greater in cervical and low paraplegia levels (T10 and below) than in high paraplegia level injuries (T1-9). Conversion from AIS B to motor incomplete was 33.9% at discharge and 53.6% at 1 year, and the initial sparing of all sacral sensory components was correlated with the greatest conversion to motor incomplete status at discharge and at 1 year. For patients with initial AIS C, the presence of voluntary anal contraction (VAC) in association with other sacral sparing was most frequently observed to improve to AIS D status at discharge. However, the presence of VAC alone as the initial sacral sparing component had the poorest prognosis for recovery to AIS D status. At follow-up, regaining sacral sparing components correlated with improvement in conversion for patients with initial AIS B and C.

CONCLUSIONS

The components of initial and follow-up sacral sparing indicated differential patterns of neurologic outcome in persons with traumatic SCI. The more sacral components initially spared, the greater the potential for recovery; and the more sacral components gained, the greater the chance of motor recovery. Consideration of whether VAC should remain a diagnostic criterion sufficient for motor incomplete classification in the absence of other qualifying sublesional motor sparing is recommended.

Spinal cord injury: how can we improve the classification and quantification of its severity and prognosis?

The preservation of functional neural tissue after spinal cord injury (SCI) is the basis for spontaneous neurological recovery. Some injured patients in the acute phase have more potential for recovery than others. This fact is problematic for the construction of clinical trials because enrollment of subjects with variable recovery potential makes it difficult to detect effects, requires large sample sizes, and risks Type II errors. In addition, the current methods to assess injury and recovery are non-quantitative and not sensitive. It is likely that therapeutic combinations will be necessary to cause substantially improved function after SCI, thus we need highly sensitive techniques to evaluate changes in motor, sensory, autonomic and other functions. We review several emerging neurophysiological techniques with high sensitivity. Quantitative methods to evaluate residual tissue sparing after severe acute SCI have not entered widespread clinical use. This reduces the ability to correlate structural preservation with clinical outcome following SCI resulting in enrollment of subjects with varying patterns of tissue preservation and injury into clinical trials. We propose that the inclusion of additional measures of injury severity, pattern, and individual genetic characteristics may enable stratification in clinical trials to make the testing of therapeutic interventions more effective and efficient. New imaging techniques to assess tract injury and demyelination and methods to quantify tissue injury, inflammatory markers, and neuroglial biochemical changes may improve the evaluation of injury severity, and the correlation with neurological outcome, and measure the effects of treatment more robustly than is currently possible. The ability to test such a multimodality approach will require a high degree of collaboration between clinical and research centers and government research support. When the most informative of these assessments is determined, it may be possible to identify patients with substantial recovery potential, improve selection criteria and conduct more efficient clinical trials.