Emotional burden among MS patients: associations between specific chronic pain diagnoses and psychological features.

Central neuropathic pain (CNP) and musculoskeletal pain (MSP) are often comorbid with multiple sclerosis (MS), yet data on the emotional burden entailed by this comorbidity are very limited. We studied whether MS patients with CNP exhibited greater emotional burden and pain severity than those with MSP and whether this emotional burden was attributed to the MS, the chronic pain, or both. Participants were 125 MS patients (55 with CNP; 30 with MSP; 40 MS pain-free) and 30 healthy controls (HCs). Participants completed questionnaires assessing pain interference, pain catastrophizing, depression, anxiety, stress, hypervigilance, and chronic pain. Group comparisons and a two-step cluster analysis were performed, and the association between cluster membership and clinical group membership was evaluated. Chronic pain was stronger and more widespread in the CNP group than in the MSP group. Both pain groups had higher pain interference, pain catastrophizing, and stress compared to MS pain-free and HC groups. All MS groups had greater depression levels compared to HCs, and the CNP group had the highest anxiety level. The "high psychological distress" cluster comprised mainly participants with CNP (57%), and the "minimal psychological distress" cluster comprised mainly the MS pain-free and HC groups. In conclusion, CNP seems to induce greater emotional burden and pain severity than does MSP. Whereas depression may be attributed to MS, and anxiety to CNP, enhanced pain interference, catastrophizing, and stress may be attributed to the comorbidity of MS and chronic pain. Identifying these traits among MS patients and targeting them in management programs may contribute to more effective, individually based care.

Differential gait adaptation patterns in Parkinson's disease - a split belt treadmill pilot study.

BACKGROUND: Interventions using split belt treadmills (SBTM) aim to improve gait symmetry (GA) in Parkinson's disease (PD). Comparative effects in conjugated SBTM conditions were not studied systematically despite potentially affecting intervention outcomes. We compared gait adaptation effects instigated by SBTM walking with respect to the type (increased\decreased speed) and the side (more/less affected) of the manipulated belt in PD. METHODS: Eight individuals with PD performed four trials of SBTM walking, each consisted of baseline tied belt configuration, followed by split belt setting - either WS or BS belt's speed increased or decreased by 50% from baseline, and final tied belt configuration. Based on the disease's motor symptoms, a 'worst' side (WS) and a 'best' side (BS) were defined for each participant. RESULTS: SB initial change in GA was significant regardless of condition (p ≤ 0.02). This change was however more pronounced for BS-decrease compared with its matching condition WS-increase (p = 0.016). Similarly, the same was observed for WS-decrease compared to BS-increase (p = 0.013). Upon returning to tied belt condition, both BS-decrease and WS-increased resulted in a significant change in GA (p = 0.04). Upper limb asymmetry followed a similar trend of GA reversal, although non-significant. CONCLUSIONS: Stronger effects on GA were obtained by decreasing the BS belt's speed of the best side, rather than increasing the speed of the worst side. Albeit a small sample size, which limits the generalisability of these results, we propose that future clinical studies would benefit from considering such methodological planning of SBTM intervention, for maximising of intervention outcomes. Larger samples may reveal arm swinging asymmetries alterations to match SBTM adaptation patterns. Finally, further research is warranted to study post-adaption effects in order to define optimal adaptation schemes to maximise the therapeutic effect of SBTM based interventions.

Heart-rate variability as a new marker for freezing predisposition in Parkinson's disease.

INTRODUCTION: Freezing of gait (FoG) is a debilitating symptom of advanced Parkinson's disease (PD) characterized by a sudden, episodic stepping arrest despite the intention to continue walking. The etiology of FoG is still unknown, but accumulating evidence unraveled physiological signatures of the autonomic nervous system (ANS) around FoG episodes. Here we aim to investigate for the first time whether detecting a predisposition for upcoming FoG events from ANS activity measured at rest is possible. METHODS: We recorded heart-rate for 1-min while standing in 28 persons with PD with FoG (PD + FoG), while OFF, and in 21 elderly controls (EC). Then, PD + FoG participants performed walking trials containing FoG-triggering events (e.g., turns). During these trials, n = 15 did experience FoG (PD + FoG+), while n = 13 did not (PD + FoG-). Most PD participants (n = 20: 10 PD + FoG+ and 10 PD + FoG-) repeated the experiment 2-3 weeks later, while ON, and none experienced FoG. We then analyzed heart-rate variability (HRV), i.e., the fluctuations in time intervals between adjacent heartbeats, mainly generated by brain-heart interactions. RESULTS: During OFF, HRV was significantly lower in PD + FoG + participants, reflecting imbalanced sympathetic/parasympathetic activity and disrupted self-regulatory capacity. PD + FoG- and EC participants showed comparable (higher) HRV. During ON, HRV did not differ among groups. HRV values did not correlate with age, PD duration, levodopa consumption, nor motor -symptoms severity scores. CONCLUSIONS: Overall, these results document for the first time a relation between HRV at rest and FoG presence/absence during gait trials, expanding previous evidence regarding the involvement of ANS in FoG.

Reliability and validity of the Hebrew version of the International Spinal Cord Injury Activities and Participation Basic Data Set.

BACKGROUND: The International Spinal Cord Injury (SCI) Activities and Participation Basic Data Set (APBDS) was created to facilitate comparisons of levels of function and disability in SCI individuals worldwide. AIM: Evaluating the reliability and validity of the APBDS's Hebrew translation was our goal. DESIGN: Observational, cross-sectional study. SETTING: University and Outpatient Rehabilitation Department of a Medical Center. POPULATION: Individuals with spinal cord injury (SCI). METHODS: The APBDS's Hebrew version was administered to fifty individuals with SCI. Reliability was evaluated through Cronbach Alpha Test and a test-retest method. Validity was determined by testing for convergence with the World Health Organization Disability Assessment Scale (WHODAS) 2.0 and the Medical Outcomes Short Form Health Survey (SF-12). RESULTS: The Hebrew APBDS had a high test-retest reliability (ICC=0.792) and an adequate Cronbach alpha test (α=0.792). Significant convergent validity was partial with both the WHODAS 2.0 (strong in the self-care objective (r=-0.648) and subjective (r=-0.666), moderate in the total objective (r=-0.640) and subjective (r=-0.570) domains of the APBDS) and the SF-12 (moderate between the total objective domain and the Physical composite score (r=0.378), poor with the Mental composite score (r=0.310)). CONCLUSIONS: Although the Hebrew APBDS's moderate reliability and validity warrants further research, it opens new vistas regarding assessment of SCI individuals' satisfaction, activity, and participation. CLINICAL REHABILITATION IMPACT: We feel that this data set may be used in the long-term follow-up of SCI individuals in the Sheba SCI rehabilitation registry.

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.

Determinants of Quality of Life in Individuals With Spinal Cord Injury Using Structural Equation Modeling.

OBJECTIVE: The objective of this study is to examine the interdependent associations between International Classification of Functioning, Disability and Health (ICF) domains and their relationship with environmental factors with regard to quality of life (QoL) in individuals with spinal cord injury (SCI). DESIGN: Survey, cross-sectional study, and model testing using structural equation modeling. SETTING: Two inpatient and outpatient SCI rehabilitation units, Sheba Medical Center and Loewenstein Hospital, Israel. PARTICIPANTS: Convenience sample of 156 individuals with SCI (N=156). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: QoL assessed by the World Health Organization Quality of Life Assessment-BREF. Neurological impairment after SCI reflected by lesion completeness and neurologic level of injury as measured by the International Standards for Neurological Classification of Spinal Cord Injury. The Spinal Cord Independence Measure to assess SCI-related task performance. ICF Brief Core Sets composition scores to assess impairment in body structure and function domains, limitations in activities, restriction in participation constructs, and the effect of environmental factors within the ICF model. RESULTS: Level of spinal cord injury and ICF Brief Core Sets composite score relating to activities and participation construct demonstrated a direct significant association with QoL. Moreover, a significant indirect association with QoL was found between the composite scores in ICF body structure and function and environmental factors, level of spinal cord injury, time since injury onset, and sex. Because the Spinal Cord Independence Measure was not related to QoL, we inferred that the categories related to instrumental activities of daily living and participation exert the most significant influence on QoL. CONCLUSIONS: In order to optimize improvements in quality of life, current rehabilitation programs should target limitations specifically related to instrumental activities of daily living and participation restrictions. It may serve as a focal point for further development of current therapeutic models and analytical methods that optimize rehabilitation planning and decision making among both health care professionals and patients.

Unique features of central neuropathic pain in multiple sclerosis: Results of a cluster analysis.

BACKGROUND: Central neuropathic pain (CNP) is an excruciating condition, prevalent in up to a third of patients with multiple sclerosis (MS). Identifying CNP among MS patients is particularly challenging considering the ample comorbid chronic pain conditions and sensory disturbances entailed by the disease. The aim was to identify sensory features unique to CNP beyond those of chronic pain and MS. METHODS: Participants were 112 MS patients: 44 with a diagnosis of CNP, 28 with a diagnosis of chronic musculoskeletal pain (MSP), and 40 pain free. Participants underwent testing of thermal and mechanical thresholds, thermal grill illusion (TGI), pain adaptation (PA), and offset analgesia (OA), and chronic pain was characterized. A two-step cluster analysis was performed, and the association between the cluster membership and the clinical group membership (CNP, MSP, pain free) was evaluated. RESULTS: The CNP and MSP groups were similar in most of the chronic pain variables (e.g., severity, location and quality) and MS-related variables (e.g., type, severity and medication intake). The three created clusters had unique sensory features: (1) 'Hyposensitivity' (increased thermal and touch thresholds) characterized the CNP group; (2) 'Poor inhibition and hyperalgesia' (worst PA and OA and decreased TGI threshold) characterized the MSP group; and (3) 'Efficient inhibition' (best PA and OA, smallest sensory loss) characterized the pain-free group. CONCLUSIONS: The unique sensory features of CNP and MSP provide insight into their pathophysiology, and evaluating them may increase the ability to provide individually based interventions. Efficient inhibition may protect MS patients from chronic pain. SIGNIFICANCE: Cluster analysis among patients with multiple sclerosis (MS) revealed that while central neuropathic pain is associated with thermal and mechanical hypoesthesia, musculoskeletal pain is involved with reduced pain inhibition and hyperalgesia; sensory profiles that provide insights into the mechanisms of these conditions and may promote an individually based pain management.

Muscle activation profile is modulated by unexpected balance loss in walking.

BACKGROUND: During an unexpected loss of balance, avoiding a fall requires people to readjust their footing rapidly and effectively. A deeper understanding of muscle activation patterns in response to unexpected balance loss will provide insights into the mechanisms of balance recovery responses. This could have implications for treatment of people with balance deficits. RESEARCH QUESTION: Explore the differences in balance recovery responses to perturbations in different phases of the gait cycle (single-support vs. double-support) in terms of biomechanical behavior (i.e., stepping and dynamic stability characteristics) and lower-limb muscle activation patterns. METHODS: Muscle activation patterns of the ankle and knee muscles and muscle fiber type recruitment resulting from unannounced, mediolateral (i.e., right/left) horizontal-surface perturbations during walking was investigated in twenty healthy adults (27.00 ± 2.79 years, ten females). Surface electromyography (sEMG) total spectral power for specific frequency bands (40-60 Hz, 60-150 Hz, 150-250 Hz, 250-400 Hz and 400-1000 Hz), from tibialis anterior (TA) and vastus lateralis (VL) muscles were analyzed. Three mixed-effects models assessed behavioral and lower-limb muscle activation patterns resulting from perturbations in the gait cycle's single- and double-support phases. Statistical significance was set a priori at p < 0.05. RESULTS: Compared to non-perturbed walking, we found a significant increase in the total spectral power of lower-extremity muscles during the first three seconds after perturbation. During the double-support phase of gait, we found a different muscle fiber type recruitment pattern between VL and TA muscles. However, there were no significant differences between VL and TA muscles for perturbations implemented in single-support phases. SIGNIFICANCE: Our findings support the notion that muscle operating frequency is modulated in real-time to fit functional goal requirements, such as a rapid change of footing in response to unexpected loss of balance in single and double-support phases of gait.

Assessment of the unmediated relationship between neurological impairment and health-related quality of life following spinal cord injury.

Objective: To assess the unmediated association between neurological impairment and quality of life (QoL) among persons with spinal cord injury (SCI), in the context of both early post-acute and long-term rehabilitation settings.Design: An observational prospective cross-sectional study.Setting: Two neurological rehabilitation centers, specializing in spinal cord injury, within a university hospital.Methods: 156 adults with spinal cord injury in the early post-acute and chronic stages of rehabilitation.Outcome Measures: Participants were categorized into tetraplegia or paraplegia groups based on neurological level of injury, and into complete or incomplete groups based on American Spinal Injury Association (ASIA) Impairment Scale (AIS) score. QoL was assessed by means of the World Health Organization Quality of Life Assessment-BREF (WHOQOL-BREF), Satisfaction with Life Scale (SWLS), Life Satisfaction Questionnaire (LISAT-9), and Personal Well-Being Index (PWI).Results: WHOQOL-BREF and PWI predicted Level of Injury group classification and WHOQOL-BREF predicted Setting group classification. None of the questionnaires differentiated between the Type of Injury groups. At the early post-acute stage of rehabilitation, the QoL scores of participants with tetraplegia and paraplegia did not differ significantly, while significantly higher QoL scores were revealed in paraplegics in the long-term setting group.Conclusions: A direct, unmediated effect of severity of neurological impairment was revealed with the WHOQOL-BREF, which distinguished between the tetraplegia and paraplegia groups, but not between the complete and incomplete injuries. QoL was significantly higher in paraplegia than in tetraplegia following the early post-acute stage of rehabilitation.

Does lack of brain injury mean lack of cognitive impairment in traumatic spinal cord injury?

OBJECTIVE: Traumatic spinal cord injury (tSCI) has implications in many areas, including cognitive functioning. Findings regarding cognitive problems in people with SCI are inconsistent, presumably due to multiple variables than can affect performance, among them emotional variables. The purpose of the current study was to elucidate cognitive sequalae in some individuals with tSCI with no medical record of brain injury, while taking emotional variables into consideration. DESIGN: Cross-sectional, with two groups. SETTING: A public rehabilitation center. PARTICIPANTS: Twenty participants with tSCI at least ten months post injury and twenty non-SCI controls, matched for sex, age, and education. INTERVENTION: None. OUTCOME MEASURES: A battery of neuropsychological tests tapping executive functions, memory, attention, and naming abilities, in addition to questionnaires assessing depression and distress. RESULTS: When emotional variables were statistically controlled, participants with tSCI showed higher levels of depression and distress and scored lower than non-SCI control participants on all cognitive tests except naming. Executive functions were found to have the highest effect size, though no specific ability was sensitive enough to differentiate between the groups in a binary logistic regression analysis. CONCLUSION: In some individuals with chronic tSCI, lower cognitive ability that is unrelated to emotional distress might result from spinal cord damage and its implications in a population who's medical records show no indication of brain injury. This highlights the importance of conducting cognitive evaluation following SCI, so that deficits can be effectively addressed during rehabilitation.

From acute to long-term alterations in pain processing and modulation after spinal cord injury: mechanisms related to chronification of central neuropathic pain.

ABSTRACT: A severe and debilitating consequence of a spinal cord injury (SCI) is central neuropathic pain (CNP). Our aim was to investigate the processes leading to CNP emergence and chronification by analyzing causal relationship over time between spinothalamic function, pain excitability, and pain inhibition after SCI. This longitudinal follow-up study included 53 patients with acute SCI and 20 healthy controls. Spinothalamic, pain excitability, and intrasegmental and extrasegmental pain inhibition indices were repeatedly evaluated at 1.5, 3, and 6 months post-SCI. Between- and within-group analyses were conducted among those patients who eventually developed CNP and those who did not. Healthy controls were evaluated twice for repeatability analysis. Patients who developed CNP, compared with those who did not, exhibited increased thermal thresholds (P < 0.05), reduced pain adaptation (P < 0.01), and conditioned pain modulation (P < 0.05), early post-injury, and the CNP group's manifestations remained worse throughout the follow-up. By contrast, allodynia frequency was initially similar across SCI groups, but gradually increased in the subacute phase onward only among the CNP group (P < 0.001), along with CNP emergence. Early worse spinothalamic and pain inhibition preceded CNP and predicted its occurrence, and early worse pain inhibition mediated the link between spinothalamic function and CNP. Crossover associations were observed between early and late pain inhibition and excitability. Inefficient intrasegmental and extrasegmental inhibition, possibly resulting from spinothalamic deafferentation, seems to ignite CNP chronification. Pain excitability probably contributes to CNP maintenance, possibly via further exhaustion of the inhibitory control. Preemptive treatment promoting antinociception early post-SCI may mitigate or prevent CNP.

End-of-life conversation from both sides of the bed: voices of family and staff.

PURPOSE: Prolonged living with chronic illness and disability expands the discussion of end-of-life conversation because of the complex role of intercommunication among patient, family, and healthcare staff. Little is known about such interaction from participants' different perspectives. This qualitative case study examined end-of-life conversation among patient, family, and staff during long-term hospitalization in a neurological rehabilitation department. METHODS: After the patient's death, 18 participants responded to in-depth semi-structured interviews: 16 healthcare staff and two family members (the patient's wife and brother). In addition, we used the wife's autoethnographic documentation of her experiences during end-of-life conversation. RESULTS: Thematic analysis produced three themes: (1) The Rehabilitation Department's Mission - Toward Life or Death? (2) The Staff's Perception of the Patient; (3) Containing Death: End-of-life Conversation from Both Sides of the Bed. These themes represented participants' different perspectives in the intercommunication in overt and covert dialogues, which changed over time. Death's presence-absence was expressed by movement between clinging to life and anticipating death. CONCLUSION: The study findings emphasize the importance of practitioners' training to accept and openly discuss death as an inseparable part of life-long disability, and the implementation of this stance during end-of-life care via sensitive conversations with patients and their families.IMPLICATIONS FOR REHABILITATIONIt is vital for rehabilitation professionals to be trained to process and accept end-of-life issues as a natural and inseparable part of the life discourse among people with disabilities and their families.Rehabilitation professionals need to acquire tools to grasp the spoken and unspoken issues related to life and death, and to communicate their impressions and understandings with people with disabilities and their families.Rehabilitation professionals need to encourage an open dialogue when communicating with people with disabilities and their families on processes related to parting and death.

Shorter Telomeres Among Individuals With Physical Disability: The Moderating Role of Perceived Stress.

OBJECTIVES: Evidence suggests that individuals with physical disability may suffer from psychological distress and accelerated cellular aging, manifested by shortened telomere length (TL), compared with healthy individuals. Studies indicate that high levels of perceived stress and depression may increase the physiological susceptibility and, thus, may contribute to a short TL. However, the moderating role of perceived stress and depression within the relationship between physical disability and TL remains unknown. METHOD: The participants consisted of 119 male subjects (mean age 54.36 years, range 35-70). Of them, 30 were able-bodied and 89 had a physical disability: 34 were due to poliomyelitis (polio) and 55 were due to spinal cord injury. Blood samples for TL analysis were collected; the participants completed questionnaires and underwent disability evaluation. RESULTS: Participants with disability had a shorter TL as well as elevated levels of perceived stress and depression compared with able-bodied controls. Both the perceived stress and depression were correlated with a shorter TL. Nonetheless, perceived stress, rather than depression, moderated the relationship between disability and TL; among participants with higher perceived stress levels, in particular, individuals with physical disability had a shorter TL than the able-bodied controls. DISCUSSION: The present findings suggest that individuals with physical disability and who exhibit high levels of perceived stress may be particularly vulnerable for accelerated cellular aging, suggesting that perceived stress can be used as a valuable target for intervention.

Bilateral leg stepping coherence as a predictor of freezing of gait in patients with Parkinson's Disease walking with wearable sensors.

Freezing of Gait (FOG) is among the most debilitating symptoms of Parkinson's Disease (PD), characterized by a sudden inability to generate effective stepping. In preparation for the development of a real-time FOG prediction and intervention device, this work presents a novel FOG prediction algorithm based on detection of altered interlimb coordination of the legs, as measured using two inertial movement sensors and analyzed using a wavelet coherence algorithm. METHODS: Fourteen participants with PD (in OFF state) were asked to walk in challenging conditions (e.g. with turning, dual-task walking, etc.) while wearing inertial motion sensors (waist, 2 shanks) and being videotaped. Occasionally, participants were asked to voluntarily stop (VOL). FOG and VOL events were identified by trained researchers based on videos. Wavelet analysis was performed on shank sagittal velocity signals and a synchronization loss threshold (SLT) was defined and compared between FOG and VOL. A proof-of-concept analysis was performed for a subset of the data to obtain preliminary classification characteristics of the novel measure. RESULTS: 128 FOG and 42 VOL episodes were analyzed. SLT occurred earlier for FOG (MED=1.81 sec prior to stop, IQR=1.57) than for VOL events (MED=0.22 sec, IQR=0.76) (Z=-4.3, p<0.001, ES=1.15). These time differences were not related with measures of disease severity. Preliminary results demonstrate sensitivity of 98%, specificity of 42% (mostly due to 'turns' detection) and balanced accuracy of 70% for SLT-based prediction, with good differentiation between FOG and VOL. CONCLUSIONS: Wavelet analysis provides a relatively simple, promising approach for prediction of FOG in people with PD.

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.

Multimodal immersive trail making-virtual reality paradigm to study cognitive-motor interactions.

BACKGROUND: Neuropsychological tests of executive function have limited real-world predictive and functional relevance. An emerging solution for this limitation is to adapt the tests for implementation in virtual reality (VR). We thus developed two VR-based versions of the classic Color-Trails Test (CTT), a well-validated pencil-and-paper executive function test assessing sustained (Trails A) and divided (Trails B) attention-one for a large-scale VR system (DOME-CTT) and the other for a portable head-mount display VR system (HMD-CTT). We then evaluated construct validity, test-retest reliability, and age-related discriminant validity of the VR-based versions and explored effects on motor function. METHODS: Healthy adults (n = 147) in three age groups (young: n = 50; middle-aged: n = 80; older: n = 17) participated. All participants were administered the original CTT, some completing the DOME-CTT (14 young, 29 middle-aged) and the rest completing the HMD-CTT. Primary outcomes were Trails A and B completion times (tA, tB). Spatiotemporal characteristics of upper-limb reaching movements during VR test performance were reconstructed from motion capture data. Statistics included correlations and repeated measures analysis of variance. RESULTS: Construct validity was substantiated by moderate correlations between the'gold standard' pencil-and-paper CTT and the VR adaptations (DOME-CTT: tA 0.58, tB 0.71; HMD-CTT: tA 0.62, tB 0.69). VR versions showed relatively high test-retest reliability (intraclass correlation; VR: tA 0.60-0.75, tB 0.59-0.89; original: tA 0.75-0.85, tB 0.77-0.80) and discriminant validity (area under the curve; VR: tA 0.70-0.92, tB 0.71-0.92; original: tA 0.73-0.95, tB 0.77-0.95). VR completion times were longer than for the original pencil-and-paper test; completion times were longer with advanced age. Compared with Trails A, Trails B target-to-target VR hand trajectories were characterized by delayed, more erratic acceleration and deceleration, consistent with the greater executive function demands of divided vs. sustained attention; acceleration onset later for older participants. CONCLUSIONS: The present study demonstrates the feasibility and validity of converting a neuropsychological test from two-dimensional pencil-and-paper to three-dimensional VR-based format while preserving core neuropsychological task features. Findings on the spatiotemporal morphology of motor planning/execution during the cognitive tasks may lead to multimodal analysis methods that enrich the ecological validity of VR-based neuropsychological testing, representing a novel paradigm for studying cognitive-motor interactions.

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.

Central Neuropathic Pain in Multiple Sclerosis Is Associated with Impaired Innocuous Thermal Pathways and Neuronal Hyperexcitability.

OBJECTIVE: About one-third of patients with multiple sclerosis (MS) suffers from chronic and excruciating central neuropathic pain (CNP). The mechanism underlying CNP in MS is not clear, since previous studies are scarce and their results are inconsistent. Our aim was to determine whether CNP in MS is associated with impairment of the spinothalamic-thalamocortical pathways (STTCs) and/or increased excitability of the pain system. DESIGN: The study was cross-sectional. SETTING: The study was conducted at a general hospital. PARTICIPANTS: Participants were 47 MS patients with CNP, 42 MS patients without CNP and 32 healthy controls. METHODS: Sensory testing included the measurement of temperature, pain, and touch thresholds and the thermal grill illusion for evaluating STTCs function and hyperpathia and allodynia as indicators of hyperexcitability. CNP was characterized using interviews and questionnaires. RESULTS: The CNP group had higher cold and warm thresholds (P < 0.01), as well as higher thermal grill illusion perception thresholds (P < 0.05), especially in painful body regions compared with controls, whereas touch and pain thresholds values were normal. The CNP group also had a significantly greater prevalence of hyperpathia and allodynia. Regression analysis revealed that whereas presence of CNP was associated with a higher cold threshold, CNP intensity and the number of painful body regions were associated with allodynia and hyperpathia, respectively. CONCLUSIONS: CNP in MS is characterized by a specific impairment of STTC function, the innocuous thermal pathways, and by pain hyperexcitability. Whereas CNP presence is associated with STTC impairment, its severity and extent are associated with pain hyperexcitability. Interventions that reduce excitability level may therefore mitigate CNP severity.

Chronic Pain and Premature Aging - The Moderating Role of Physical Exercise.

Chronic pain induces a multitude of harmful effects; recently it has been suggested that chronic pain is also associated with premature aging, manifested in shortened telomere length (TL). However, evidence for this hypothesis is scarce and inconsistent. The aim was twofold: 1) Investigate whether chronic pain is associated with premature aging, and 2) Determine whether physical exercise (PE) moderates this association if it exists. Participants were 116 male subjects, with (n = 67) and without chronic pain (n = 49). Blood samples for TL analysis were collected and participants were interviewed and completed questionnaires. As a part of the cohort, we included people with physical disability; this variable was controlled in the analysis. The TL of individuals with chronic pain was significantly shorter than that of pain-free individuals. Regression analysis revealed a significant moderating effect of PE on chronic pain and TL, above and beyond the effects of disability, age, and weight. Whereas chronic pain was associated with shorter telomeres in participants who did not exercise, this association was nonsignificant among participants who did exercise. The results suggest that chronic pain is associated with premature ageing; however, PE may mitigate this association and may protect individuals against the harmful effects of chronic pain. PERSPECTIVE: The study suggests that it is important to monitor signs of premature ageing among chronic pain patients as they are at risk. However, chronic pain patients may benefit from regular PE in this respect as it may moderate premature ageing.

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.