Clinical Subsets of Central Cord Syndrome: Is It a Distinct Entity from Other Forms of Incomplete Tetraplegia for Research?

Central cord syndrome (CCS) is the most prevalent and debated incomplete spinal cord injury (SCI) syndrome, with its hallmark feature being more pronounced weakness of the upper extremities than of the lower extremities. Varying definitions encapsulate multiple clinical features under the single umbrella term of CCS, complicating evaluation of its frequency, prognosis discussions, and outcomes research. Often, people with CCS are excluded from research protocols, as it is thought to have a favorable prognosis, but the vague nature of CCS raises doubts about the validity of this practice. The objective of this study was to categorize CCS into specific subsets with clear quantifiable differences, to assess whether this would enhance the ability to determine if individuals with CCS or its subsets exhibit distinct neurological and functional outcomes relative to others with incomplete tetraplegia. This study retrospectively reviewed individuals with new motor incomplete tetraplegia from traumatic SCI who enrolled in the Spinal Cord Injury Model Systems (SCIMS) database from 2010 to 2020. Through an assessment of the prevailing criteria for CCS, coupled with data analysis, we used two key criteria, including the severity of distal upper extremity weakness (i.e., hands and fingers) and extent of symmetry, to delineate three CCS subsets: full CCS, unilateral CCS, and borderline CCS. Of the 1490 participants in our sample, 17.5% had full, 25.6% had unilateral, and 9% had borderline CCS, together encompassing >50% of motor incomplete tetraplegia cases. Despite the increased sensitivity and specificity of these subsets compared with existing quantifiable criteria, substantial variability in clinical presentation was still observed. Overall, individuals meeting CCS subset criteria showed a higher likelihood of American Spinal Injury Association (ASIA) Impairment Scale (AIS) D grade than those with motor incomplete tetraplegia without CCS. Upper Extremity Motor Score (UEMS) for those with CCS was lower on admission, a difference that diminished by discharge, whereas their Lower Extremity Motor Score (LEMS) consistently remained higher than for those without CCS. However, these neurological distinctions did not result in significant functional differences, as lower and upper extremity functional outcomes at discharge were mostly similar, with some differences observed within those with AIS D grade. The AIS grade, rather than the diagnosis of CCS, remains the foremost determinant influencing neurological and functional outcomes. We recommend that future studies consider incorporating motor incomplete tetraplegia into their inclusion/exclusion criteria, instead of relying on criteria specific to CCS. Although there remains clinical value in characterizing an injury pattern as CCS and perhaps using the different subsets to better characterize the impairments, it does not appear to be a useful research criterion.

Central cord syndrome definitions, variations and limitations.

Central cord syndrome (CCS) is the most common, yet most controversial, among the different spinal cord injury (SCI) incomplete syndromes. Since its original description in 1954, many variations have been described while maintaining the core characteristic of disproportionate weakness in the upper extremities compared to the lower extremities. Several definitions have been proposed in an attempt to quantify this difference, including a widely accepted criterion of ≥10 motor points in favor of the lower extremities. Nevertheless, recent reports have recommended revisiting the terminology and criteria of CCS as existing definitions do not capture the entire essence of the syndrome. Due to methodological differences, the full extent of CCS is not known, and a large variation in prevalence has been described. This review classifies the different definitions of CCS and describes some inherent limitations, highlighting the need for universal quantifiable criteria.

A multi-center international study on the spinal cord independence measure, version IV: Rasch psychometric validation.

CONTEXT: The Spinal Cord Independence Measure is a comprehensive functional rating scale for individuals with spinal cord lesion (SCL). OBJECTIVE: To validate the scores of the three subscales of SCIM IV, the fourth version of SCIM, using advanced statistical methods. STUDY DESIGN: Multi-center cohort study. SETTING: Nineteen SCL units in 11 countries. METHODS: SCIM developers created SCIM IV following comments by experts, included more accurate definitions of scoring criteria in the SCIM IV form, and adjusted it to assess specific conditions or situations that the third version, SCIM III, does not address. Professional staff members assessed 648 SCL inpatients, using SCIM IV and SCIM III, at admission to rehabilitation, and at discharge. The authors examined the validity and reliability of SCIM IV subscale scores using Rasch analysis. RESULTS: The study included inpatients aged 16-87 years old. SCIM IV subscale scores fit the Rasch model. All item infit and most item outfit mean-square indices were below 1.4; statistically distinct strata of abilities were 2.6-6; most categories were properly ordered; item hierarchy was stable across most clinical subgroups and countries. In a few items, however, we found misfit or category threshold disordering. We found SCIM III and SCIM IV Rasch properties to be comparable. CONCLUSIONS: Rasch analysis suggests that the scores of each SCIM IV subscale are reliable and valid. This reinforces the justification for using SCIM IV in clinical practice and research.

Incomplete Spinal Cord Syndromes: Current Incidence and Quantifiable Criteria for Classification.

The demographics of acute traumatic spinal cord injury (SCI) have changed over the last few decades, with a significant increase in age at the time of injury, a higher percentage of injuries caused by falls, and incomplete tetraplegia becoming the most common type of neurological impairment. Incomplete SCI syndromes, most specifically central cord syndrome (CCS), anterior cord syndrome (ACS) and Brown-Sequard syndrome (BSS), constitute a substantial proportion of incomplete tetraplegia and SCI overall. Nevertheless, the updated incidence of these syndromes is not well known, and their estimates vary considerably, largely because of methodological inconsistencies across previous studies. A retrospective analysis of individuals with new traumatic SCI enrolled in the Spinal Cord Injury Model Systems database between January 2011 and May 2020 was performed. Using newly proposed computable definitions for ACS and BSS, as well as an existing quantitative definition of CCS, we determined the current incidence and neurological characteristics of each syndrome. Within the population of individuals with a traumatic SCI, including all levels and severity of injuries (N = 3639), CCS, ACS, and BSS accounted for 14%, 6.5%, and 2%, respectively. Of the 1649 individuals with incomplete tetraplegia in our cohort, CCS was the most common syndrome (30%), followed by ACS (10%) and BSS (3%). Using quantifiable definitions, these three syndromes now account for ∼22% and ∼44% of cases of traumatic SCI and incomplete tetraplegia, respectively, with CCS having increased over the last decade. This updated information and proposed calculable criteria for these syndromes allow for a greater understanding of the incidence and characteristics of these syndromes and enable greater study in the future.

Transcutaneous spinal stimulation in patients with intrathecal baclofen pump delivery system: A preliminary safety study.

Objective: To determine the effect of transcutaneous spinal stimulation (TSS) on an implanted intrathecal baclofen (ITB) pump in persons with traumatic spinal cord injury (SCI). Design: Prospective clinical trial. Participants: Five individuals with chronic traumatic SCI, >18 years of age, and an anteriorly implanted Medtronic SynchroMed™ II ITB pump delivery system. Intervention: Transcutaneous spinal stimulation trials with cathode at T11/12, with pump interrogation before, during and after stimulation. Results: There was no evidence of any effect of the TSS in regards to disruption of the ITB pump delivery mechanism. Communication interference with the interrogator to the pump occurred often during stimulation for log transmission most likely secondary to the electromagnetic interference from the stimulation. One individual had elevated blood pressure at the end of the trial, suspected to be unrelated to the spinal stimulation. Conclusion: Based upon this pilot study, further TSS studies including persons with an implanted Medtronic SynchroMed™ II ITB pump can be considered when stimulating at the low thoracic spine, although communication with the programmer during the stimulation may be affected.

Reliability Validity and Responsiveness of the Spinal Cord Independence Measure 4th Version in a Multicultural Setup.

OBJECTIVE: To examine the fourth version of the Spinal Cord Independence Measure for reliability and validity. DESIGN: Partly blinded comparison with the criterion standard Spinal Cord Independence Measure III, and between examiners and examinations. SETTING: A multicultural cohort from 19 spinal cord injury units in 11 countries. PARTICIPANTS: A total of 648 patients with spinal cord injury. INTERVENTION: Assessment with Spinal Cord Independence Measure (SCIM IV) and Spinal Cord Independence Measure (SCIM III) on admission to inpatient rehabilitation and before discharge. MAIN OUTCOME MEASURES: SCIM IV interrater reliability, internal consistency, correlation with and difference from SCIM III, and responsiveness. RESULTS: Total agreement between examiners was above 80% on most SCIM IV tasks. All Kappa coefficients were above 0.70 and statistically significant (P<.001). Pearson's coefficients of the correlation between the examiners were above 0.90, and intraclass correlation coefficients were above 0.90. Cronbach's alpha was above 0.96 for the entire SCIM IV, above 0.66 for the subscales, and usually decreased when an item was eliminated. Reliability values were lower for the subscale of respiration and sphincter management, and on admission than at discharge. SCIM IV and SCIM III mean values were very close, and the coefficients of Pearson correlation between them were 0.91-0.96 (P<.001). The responsiveness of SCIM IV was not significantly different from that of SCIM III in most of the comparisons. CONCLUSIONS: The validity, reliability, and responsiveness of SCIM IV, which was adjusted to assess specific patient conditions or situations that SCIM III does not address, and which includes more accurate definitions of certain scoring criteria, are very good and quite similar to those of SCIM III. SCIM IV can be used for clinical and research trials, including international multi-center studies, and its group scores can be compared with those of SCIM III.

Functional outcomes following inpatient rehabilitation of Guillain-Barré syndrome patients: Intravenous immunoglobulins versus plasma exchange.

BACKGROUND: Treatment with either Intravenous immunoglobulin (IVIg) or plasma exchange (PE) in patients with Guillain-Barré Syndrome (GBS) showed equivalent efficacy as attested by a commonly used disability scale. However, it has been suggested that this scale may not be sensitive enough to detect subtle functional changes between the two treatments since it mainly focuses on walking capability and respiratory function. OBJECTIVE: To evaluate functional outcomes following treatment with IVIg or PE using comprehensive scales that incorporate parameters of basic activities of daily living. METHODS: A retrospective cohort study was conducted between 2007 and 2013 in an inpatient neurologic rehabilitation department. The study group included 70 individuals with GBS: 39 were treated with PE and 31 with IVIg. A comparison of functional outcomes was performed using Functional Independence Measure (FIM), rehabilitation efficiency (REy), rehabilitation effectiveness (REs), and the GBS disability scale (GDS). RESULTS: Both treatments had a comparable effect on the various functional outcomes. Patients showed a significant increase in total FIM scores (30 points on average) during rehabilitation mainly as a result of an increase in motor sub-scores. A mean improvement of 1.23 (SD 0.9) in GDS was also observed. On average, individuals with GBS spent 20 days combined in the acute departments and 61 days in the rehabilitation department, with length of stay being similar for both treatments. CONCLUSIONS: IVIg and PE treatments have similar basic activities of daily living (ADL) functional outcomes. Nevertheless, due to the different mechanism of actions of these treatments and the multitude of GBS variants, it is possible that further comprehensive assessment tools may demonstrate differences in activity and participation of individuals with GBS.

Early Trauma Predictors of Mobility in People with Spinal Cord Injury.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: This study aims to assess the potential value of very early trauma variables such as Abbreviated Injury Scale (AIS) and the Injury Severity Score for predicting independent ambulation following a traumatic spinal cord injury (TSCI). SUMMARY OF BACKGROUND DATA: Several models for prediction of ambulation early after TSCI have been published and validated. The vast majority rely on the initial examination of American Spinal Injury Association (ASIA) impairment scale and level of injury; however, in many locations and clinical situations this examination is not feasible early after the injury. METHODS: Patient characteristics, trauma data, and ASIA scores on admission to rehabilitation were collected for each of the 144 individuals in the study. Outcome measure was the indoor mobility item of the Spinal Cord Independence Measure taken upon discharge from rehabilitation. Univariate and multivariable models were created for each predictor, Odds ratios (ORs) were obtained by a multivariable logistic regression analysis, and area under the receiver operator curve was calculated for each model. RESULTS: We observed a significant correlation between the trauma variables and independent ambulation upon discharge from rehabilitation. Of the early variables, the AIS for the spine region showed the strongest correlation. CONCLUSION: These findings support using preliminary trauma variables for early prognostication of ambulation following a TSCI, allowing for tailored individual interventions.Level of Evidence: 3.

The effect of age and injury severity on clinical prediction rules for ambulation among individuals with spinal cord injury.

BACKGROUND CONTEXT: While several models for predicting independent ambulation early after traumatic spinal cord injury (SCI) based upon age and specific motor and sensory level findings have been published and validated, their accuracy, especially in individual American Spinal Injury Association [ASIA] Impairment Scale (AIS) classifications, has been questioned. Further, although age is widely used in prediction rules, its role and possible modifications have not been adequately evaluated until now. PURPOSE: To evaluate the predictive accuracy of existing clinical prediction rules for independent ambulation among individuals at spinal cord injury model systems (SCIMS) Centers as well as the effect of modifying the age parameter from a cutoff of 65 years to 50 years. STUDY DESIGN: Retrospective analysis of a longitudinal database. PATIENT SAMPLE: Adult individuals with traumatic SCI. OUTCOME MEASURES: The FIM locomotor score was used to assess independent walking ability at the 1-year follow-up. METHODS: In all, 639 patients were enrolled in the SCIMS database between 2011 and 2015, with complete neurological examination data within 15 days following the injury and a follow-up assessment with functional independence measure (FIM) at 1-year post injury. Two previously validated logistic regression models were evaluated for their ability to predict independent walking at 1-year post injury with participants in the SCIMS database. Area under the receiver operating curve (AUC) was calculated for the individual AIS categories and for different age groups. Prediction accuracy was also calculated for a new modified LR model (with cut-off age of 50). RESULTS: Overall AUC for each of the previous prediction models was found to be consistent with previous reports (0.919 and 0.904). AUCs for grouped AIS levels (A+D, B+C) were consistent with prior reports, moreover, prediction for individual AIS grades continued to reveal lower values. AUCs by different age categories showed a decline in prognostication accuracy with an increase in age, with statistically significant improvement of AUC when age-cut off was reduced to 50. CONCLUSIONS: We confirmed previous results that former prediction models achieve strong prognostic accuracy by combining AIS subgroups, yet prognostication of the separate AIS groups is less accurate. Further, prognostication of persons with AIS B+C, for whom a clinical prediction model has arguably greater clinical utility, is less accurate than those with AIS A+D. Our findings emphasize that age is an important factor in prognosticating ambulation following SCI. Prediction accuracy declines for older individuals compared with younger ones. To improve prediction of independent ambulation, the age of 50 years may be a better cutoff instead of age of 65.

Biomarkers for predicting central neuropathic pain occurrence and severity after spinal cord injury: results of a long-term longitudinal study.

Central neuropathic pain (CNP) after spinal cord injury (SCI) is debilitating and immensely impacts the individual. Central neuropathic pain is relatively resistant to treatment administered after it develops, perhaps owing to irreversible pathological processes. Although preemptive treatment may overcome this shortcoming, its administration necessitates screening patients with clinically relevant biomarkers that could predict CNP early post-SCI. The aim was to search for such biomarkers by measuring pronociceptive and for the first time, antinociceptive indices early post-SCI. Participants were 47 patients with acute SCI and 20 healthy controls. Pain adaptation, conditioned pain modulation (CPM), pain temporal summation, wind-up pain, and allodynia were measured above, at, and below the injury level, at 1.5 months after SCI. Healthy control were tested at corresponding regions. Spinal cord injury patients were monitored for CNP emergence and characteristics at 3 to 4, 6 to 7, and 24 months post-SCI. Central neuropathic pain prevalence was 57.4%. Central neuropathic pain severity, quality, and aggravating factors but not location somewhat changed over 24 months. Spinal cord injury patients who eventually developed CNP exhibited early, reduced at-level pain adaptation and CPM magnitudes than those who did not. The best predictor for CNP emergence at 3 to 4 and 7 to 8 months was at-level pain adaptation with odds ratios of 3.17 and 2.83, respectively (∼77% probability) and a cutoff value with 90% sensitivity. Allodynia and at-level CPM predicted CNP severity at 3 to 4 and 24 months, respectively. Reduced pain inhibition capacity precedes, and may lead to CNP. At-level pain adaptation is an early CNP biomarker with which individuals at risk can be identified to initiate preemptive treatment.

Aspirin Response Test role in platelet transfusion following intracerebral hemorrhage.

OBJECTIVES: Spontaneous intracerebral hemorrhage (ICH) results in high morbidity and mortality. A target for therapy might be hematoma expansion, which occurs in a significant proportion of patients, and can be exacerbated by antiplatelet medications, such as aspirin. It is not clear whether platelet transfusion neutralizes aspirin. The Aspirin Response Test (ART) is commonly ordered in this patient population, but it is not clear whether the results of this test can help select patients for transfusion of platelets. The aim of our study is to investigate whether a selected group of ICH patients, those with reduced platelet activity ("aspirin responders"), will benefit from platelet transfusion. MATERIALS AND METHODS: This retrospective study included 63 patients who were taking aspirin but no other antithrombotic medication prior to the ICH. For each patient, we measured hematoma size by head CT on admission and compared with follow-up head CT 1 day later. RESULTS: In the general cohort, 41% of transfused patients and 29% of non-transfused patients had a hematoma expansion. In the "aspirin responders" group, 46% of transfused patients and 22% of non-transfused patients had an expansion. CONCLUSIONS: Our data suggest that platelet transfusion following an ICH in "aspirin responders" does not reduce hematoma expansion rates in those patients. A larger prospective study is needed.