Handrim Wheelchair Propulsion Technique in Individuals With Spinal Cord Injury With and Without Shoulder Pain: A Cross-sectional Comparison.

OBJECTIVE: The aim of this study was to compare handrim wheelchair propulsion technique between individuals with spinal cord injury with and without shoulder pain. DESIGN: A cross-sectional study including 38 experienced handrim wheelchair users with spinal cord injury was conducted. Participants were divided into the "shoulder pain" ( n = 15) and "no-shoulder pain" ( n = 23) groups using the Local Musculoskeletal Discomfort scale. Kinetic and spatiotemporal aspects of handrim wheelchair propulsion during submaximal exercise on a motor-driven treadmill were analyzed. Data were collected using a measurement wheel instrumented with three-dimensional force sensors. RESULTS: After correction for confounders (time since injury and body height), linear regression analyses showed that the pain group had a 0.30-sec (95% confidence interval, -0.5 to -0.1) shorter cycle time, 0.22-sec (95% confidence interval, -0.4 to -0.1) shorter recovery time, 15.6 degrees (95% confidence interval, -27.4 to -3.8) smaller contact angle, and 8% (95% confidence interval, -15 to 0) lower variability in work per push compared with the no-pain group. Other parameters did not differ between groups. CONCLUSIONS: This study indicates that individuals with spinal cord injury who experience shoulder pain propel their handrim wheelchair kinematically differently from individuals with spinal cord injury without shoulder pain. This difference in propulsion technique might be a pain-avoiding mechanism aimed at decreasing shoulder range of motion.

Increased Ipsilateral M1 Activation after Incomplete Spinal Cord Injury Facilitates Motor Performance.

Incomplete spinal cord injury (SCI) may result in muscle weakness and difficulties with force gradation. Although these impairments arise from the injury and subsequent changes at spinal levels, changes have also been demonstrated in the brain. Blood-oxygen-level dependent (BOLD) imaging was used to investigate these changes in brain activation in the context of unimanual contractions with the first dorsal interosseous muscle. BOLD- and force data were obtained in 19 individuals with SCI (AISA Impairment Scale [AIS] C/D, level C4-C8) and 24 able-bodied controls during maximal voluntary contractions (MVCs). To assess force modulation, participants performed 12 submaximal contractions with each hand (at 10, 30, 50, and 70% MVC) by matching their force level to a visual target. MVCs were weaker in the SCI group (both hands p < 0.001), but BOLD activation did not differ between SCI and control groups. For the submaximal contractions, force (as %MVC) was similar across groups. However, SCI participants showed increased activity of the ipsilateral motor cortex and contralateral cerebellum across all contractions, with no differential effect of force level. Activity of ipsilateral M1 was best explained by force of the target hand (vs. the non-target hand). In conclusion, the data suggest that after incomplete cervical SCI, individuals remain capable of producing maximal supraspinal drive and are able to modulate this drive adequately. Activity of the ipsilateral motor network appears to be task related, although it remains uncertain how this activity contributes to task performance and whether this effect could potentially be harnessed to improve motor functioning.

Motor learning outcomes of handrim wheelchair propulsion during active spinal cord injury rehabilitation in comparison with experienced wheelchair users.

PURPOSE: To investigate changes in wheelchair propulsion technique and mechanical efficiency across first five weeks of active inpatient spinal cord injury rehabilitation and to compare the outcomes at discharge with experienced wheelchair users with spinal cord injury. METHODS: Eight individuals with recent spinal cord injury performed six weekly submaximal exercise tests. The first and last measurement additionally contained a wheelchair circuit and peak graded exercise test. Fifteen experienced individuals performed all above-mentioned tests on one occasion. RESULTS: Mechanical efficiency and propulsion technique did not change during the five weeks of inpatient rehabilitation. Peak power output during peak graded test and performance time on the wheelchair circuit improved between the first and the last week. No difference in propulsion technique, peak power output, and performance time was found between the persons with a recent injury and the experienced group. Mechanical efficiency was higher after the correction for the difference in relative power output in the experienced group. CONCLUSION: The group with a recent injury did not improve mechanical efficiency and propulsion technique over the period of active rehabilitation, despite significant improvements on the wheelchair circuit and in work capacity. The only significant difference between the groups was found in mechanical efficiency.Implications for rehabilitationThe lack of time-dependent changes in mechanical efficiency and propulsion technique in the group with a recent spinal cord injury, combined with the lack of differences in technique, work capacity and on the wheelchair circuit between the groups, suggest that important adaptations of motor learning may happen even earlier in rehabilitation and emphasize that the group in active rehabilitation was relatively skilled.Standardized observational analyses of handrim wheelchair propulsion abilities during early spinal cord injury rehabilitation provide detailed understanding of wheelchair technique, skill as well as wheelchair propulsion capacity.Measurement of external power output is critical to interpretation of gross efficiency, propulsion technique, and capacity.Wheelchair quality and body weight - next to wheelchair fitness and skill - require careful consideration both in early rehabilitation as well as in the chronic phase of spinal cord injury.

Aerobic Exercise Therapy in Ambulatory Patients With ALS: A Randomized Controlled Trial.

BACKGROUND: Weakness caused by motor neuron degeneration in amyotrophic lateral sclerosis (ALS) may result in avoidance of physical activity, resulting in deconditioning and reduced health-related quality of life (HRQoL). OBJECTIVE: To study the effectiveness of aerobic exercise therapy (AET) on disease-specific and generic HRQoL in ambulatory patients with ALS. METHODS: We conducted a multicenter, assessor-blinded, randomized controlled trial. Using a biphasic randomization model, ambulatory ALS patients were assigned (1:1) to AET+usual care (UC), or UC. AET consisted of a 16-week aerobic cycling exercise program. Primary outcome measures were the 40-item ALS assessment questionnaire (ALSAQ-40), and the mental component summary (MCS) and physical component summary (PCS) scores of the short-form survey (SF-36), using linear mixed effects models. Per-protocol (PP) analysis was performed for those patients who attended ≥75% of the training sessions; controls were matched (1:1) by propensity score matching. RESULTS: Of 325 screened patients, 57 were randomized: 27 to AET+UC and 30 to UC. No significant mean slope differences between groups were observed for ALSAQ-40 (-1.07; 95% confidence interval [CI] -2.6 to 0.5, P=0.172) nor for SF-36 MCS (0.24; -0.7 to 1.1, P=0.576) or PCS (-0.51; -1.4 to 0.38, P=0.263). There were no adverse events related to the AET. PP-analyses showed significantly less deterioration in ALSAQ-40 (-1.88, -3.8 to 0.0, P=0.046) in AET+UC compared to UC. CONCLUSIONS: AET+UC was not superior to UC alone in preserving HRQoL in ambulatory ALS patient. However, the study was unfortunately underpowered, because only 10 patients completed the protocol. AET+UC may preserve disease-specific HRQoL in slow progressors. CLINICAL TRIAL REGISTRATION NUMBER: Netherlands National Trial Register (NTR): 1616.

Computer and internet use among people with long-standing spinal cord injury: a cross-sectional survey in the Netherlands.

STUDY DESIGN: Cross-sectional survey OBJECTIVES: To describe computer and Internet use (other than for work or study) among people with long-standing spinal cord injury (SCI), examine associations between demographic and lesion characteristics and Internet use, and examine associations between Internet use and mental health, participation, and life satisfaction. SETTING: Community, The Netherlands METHODS: Participants were 265 individuals living with SCI for at least 10 years, who were 18-35 at the onset of SCI, aged 28-65 at the time of the study and wheelchair-user. Scales for General and Health-related Internet use were developed. RESULTS: Nearly all (97.7%) participants had Internet access and 98.4% of those used it daily or weekly. Of those with tetraplegia, 47.4% had assistive devices for computer use. General Internet use, such as following news and online banking, was very frequent. Websites with information on general health or accessibility were typically visited a few times a year. Three-quarters never visited websites of other individuals with SCI or foreign websites with information on SCI. General Internet use was associated with male gender, younger age, and higher education. Participants with tetraplegia scored higher on Health-related Internet use compared to participants with paraplegia. Health-related Internet use was associated with worse participation, but not with the other psychosocial variables. CONCLUSION: Internet has become part of daily life of people with SCI in the Netherlands. However, only one association between Internet use and indicators of psychosocial functioning was found. Possible underuse of adaptive devices and of SCI-specific websites warrant further investigation.

Neurological and functional recovery in tuberculosis patients with spinal cord injury in The Netherlands.

BACKGROUND: Spinal tuberculosis (TB) accounts for approximately 1% to 3% of all TB cases and it can cause a wide range of neurological symptoms, from none to a complete spinal cord injury (SCI), resulting in complete paraplegia or tetraplegia. OBJECTIVES: To describe the functional and neurological outcome of SCI caused by TB. METHODS: Retrospective data on the admission period was combined with prospectively collected data on long-term follow-up. Primary outcome was neurological outcome in terms of motor function. Secondary outcome measures were functional outcome in terms of level of independence and community participation. Results were compared to the outcome in patients with SCI due to trauma. RESULTS: Six TB patients with complete motor SCI (American Spinal Injury Association Impairment Scale (AIS) A or B) were compared to eighteen patients with traumatic SCI. Most TB patients regained almost full neurological function (median motor score improved from 50 to 100), and reached high levels of independence, whereas trauma patients did not improve neurologically (median motor score remained 50) and reached a plateau in level of independence. CONCLUSIONS: SCI due to tuberculosis in the Netherlands shows remarkable improvement in both neurological and functional outcome, especially compared with traumatic SCI.

Bladder-emptying methods, neurogenic lower urinary tract dysfunction and impact on quality of life in people with long-term spinal cord injury.

OBJECTIVES: To describe bladder-emptying methods used by people with long-term spinal cord injury (SCI) and to determine usage differences in relation to time since injury, sex, lesion level and completeness of lesion. Furthermore, to evaluate the relationship between bladder-emptying methods and the impact of neurogenic lower urinary tract dysfunction (NLUTD) on quality of life (QoL). DESIGN: Cross-sectional multicenter study. SETTING: Dutch community. PARTICIPANTS: Persons dependent on wheelchairs (N = 282) with traumatic or non-traumatic SCI for ≥10 years and age at injury of 18-35 years. INTERVENTIONS: Not applicable. OUTCOME MEASURES: The International Lower Urinary Tract Function Basic SCI Data Set and the Short-Form Qualiveen (SF-Qualiveen). RESULTS: Median time since injury was 22.0 years (IQR: 16.8-30.3). Clean intermittent catheterization (CIC) was most commonly used (42.6%). Longer time since injury was associated with fewer continent urinary diversions and more transurethral catheter use. Transurethral catheter use and continent urinary diversions were more prevalent among women. Participants with tetraplegia were more likely to use reflex voiding or a suprapubic catheter, and participants with paraplegia were more likely to use CIC. Transurethral catheter users reported the highest impact of NLUTD on quality of life (SF-Qualiveen score: 1.9; SD = 0.8). Participants with a continent urinary diversion reported the lowest impact (SF-Qualiveen score: 0.9; SD = 0.6). Higher age and indwelling catheter use versus CIC were associated with a higher impact of NLUTD on QoL. CONCLUSIONS: CIC is the most common bladder-emptying method in Dutch people with long-term SCI. Clinicians should be aware of the impact of NLUTD on QoL, especially for those using an indwelling catheter.

Metabolic syndrome in people with a long-standing spinal cord injury: associations with physical activity and capacity.

This study investigated (i) the prevalence of the metabolic syndrome (MetS) in people with a long-standing spinal cord injury (SCI); (ii) whether personal or lesion characteristics are determinants of the MetS; and (iii) the association with physical activity or peak aerobic capacity on the MetS. In a cross-sectional study, persons with SCI (N = 223; time since injury of ≥10 years) were tested. The individual components of the MetS were assessed together with the physical activity measured by the Physical Activity Scale for Individuals with Physical Disabilities (PASIPD), while peak aerobic capacity was tested during a graded wheelchair exercise test on a treadmill. Thirty-nine percent of the participants had MetS. In a multivariate logistic regression analyses and after performing a backward regression analysis, only age and education were significant determinants of the MetS. A 10-year increase in age leads to a 1.5 times more chance to have the MetS. Furthermore, people with a low education will multiply the relative risk of MetS compared with people with high education by almost 2. With and without correcting for confounders, no significant relationship was found between PASIPD or peak aerobic capacity and the MetS. It can be concluded that the prevalence of the MetS is high (39%) in people with a long-standing SCI but is comparable to the general Dutch population. Older people and those with a lower education level are most at risk for the MetS. Physical activity and peak aerobic fitness were not related to the MetS in this group with a long-standing SCI.

Recovery of motor imagery ability in the first year after stroke.

The aim of this study was to examine the level and recovery of motor imagery ability (MIA) in the first year after stroke and whether the recovery of MIA is related to that of arm/hand function. Twenty-three patients with diminished arm/hand function were included. The accuracy score on the hand laterality judgment task was used to assess MIA and the Fugl-Meyer Assessment was used to evaluate the recovery of arm/hand function. The patients were assessed 3, 6, 16, 26, and 52 weeks after stroke. In the first year after stroke, the percentage of patients with moderate to good MIA improved from 78% after 3 weeks to 94% after 1 year. The recovery of MIA took place in the first 6 weeks after stroke. No correlation was found between the recovery of MIA and arm/hand function, despite the fact that the greatest improvement in both occurred in the first 6 weeks.

Use of whole-genome sequencing to trace, control and characterize the regional expansion of extended-spectrum ß-lactamase producing ST15 Klebsiella pneumoniae.

The study describes the transmission of a CTX-M-15-producing ST15 Klebsiella pneumoniae between patients treated in a single center and the subsequent inter-institutional spread by patient referral occurring between May 2012 and September 2013. A suspected epidemiological link between clinical K. pneumoniae isolates was supported by patient contact tracing and genomic phylogenetic analysis from May to November 2012. By May 2013, a patient treated in three institutions in two cities was involved in an expanding cluster caused by this high-risk clone (HiRiC) (local expansion, CTX-M-15 producing, and containing hypervirulence factors). A clone-specific multiplex PCR was developed for patient screening by which another patient was identified in September 2013. Genomic phylogenetic analysis including published ST15 genomes revealed a close homology with isolates previously found in the USA. Environmental contamination and lack of consistent patient screening were identified as being responsible for the clone dissemination. The investigation addresses the advantages of whole-genome sequencing in the early detection of HiRiC with a high propensity of nosocomial transmission and prolonged circulation in the regional patient population. Our study suggests the necessity for inter-institutional/regional collaboration for infection/outbreak management of K. pneumoniae HiRiCs.

Low-intensity wheelchair training in inactive people with long-term spinal cord injury: A randomized controlled trial on fitness, wheelchair skill performance and physical activity levels.

OBJECTIVE: To investigate the effects of low-intensity wheelchair training on wheelchair-specific fitness, wheelchair skill performance and physical activity levels in inactive people with long-term spinal cord injury. DESIGN: Randomized controlled trial. PARTICIPANTS: Inactive manual wheelchair users with spinal cord injury for at least 10 years (n = 29), allocated to exercise (n = 14) or no exercise. METHODS: The 16-week training consisted of wheelchair treadmill-propulsion at 30-40% heart rate reserve or equi-valent in terms of rate of perceived exertion, twice a week, for 30 min per session. Wheelchair-specific fitness was determined as the highest 5-s power output over 15-m overground wheelchair sprinting (P5-15m), isometric push-force, submaximal fitness and peak aerobic work capacity. Skill was determined as performance time, ability and strain scores over a wheelchair circuit. Activity was determined using a questionnaire and an odometer. RESULTS: Significant training effects appeared only in P5-15m (exercise vs control: mean +2.0 W vs -0.7 W, p = 0.017, ru=0.65). CONCLUSION: The low-intensity wheelchair training appeared insufficient for substantial effects in the sample of inactive people with long-term spinal cord injury, presumably in part owing to a too-low exercise frequency. Effective yet feasible and sustainable training, as well as other physical activity programmes remain to be developed for inactive people with long-term spinal cord injury.

Reduced voluntary drive during sustained but not during brief maximal voluntary contractions in the first dorsal interosseous weakened by spinal cord injury.

In able-bodied (AB) individuals, voluntary muscle activation progressively declines during sustained contractions. However, few data are available on voluntary muscle activation during sustained contractions in muscles weakened by spinal cord injury (SCI), where greater force declines may limit task performance. SCI-related impairment of muscle activation complicates interpretation of the interpolated twitch technique commonly used to assess muscle activation. We attempted to estimate and correct for the SCI-related-superimposed twitch. Seventeen participants, both AB and with SCI (American Spinal Injury Association Impairment Scale C/D) produced brief and sustained (2-min) maximal voluntary contractions (MVCs) with the first dorsal interosseous. Force and electromyography were recorded together with superimposed (doublet) twitches. MVCs of participants with SCI were weaker than those of AB participants (20.3 N, SD 7.1 vs. 37.9 N, SD 9.5; P < 0.001); MVC-superimposed twitches were larger in participants with SCI (SCI median 10.1%, range 2.0-63.2%; AB median 4.7%, range 0.0-18.4% rest twitch; P = 0.007). No difference was found after correction for the SCI-related-superimposed twitch (median 6.7%, 0.0-17.5% rest twitch, P = 0.402). Thus during brief contractions, the maximal corticofugal output that participants with SCI could exert was similar to that of AB participants. During the sustained contraction, force decline (SCI, 58.0%, SD 15.1; AB, 57.2% SD 13.3) was similar (P = 0.887) because participants with SCI developed less peripheral (P = 0.048) but more central fatigue than AB participants. The largest change occurred at the start of the sustained contraction when the (corrected) superimposed twitches increased more in participants with SCI (SCI, 16.3% rest twitch, SD 20.8; AB, 2.7%, SD 4.7; P = 0.01). The greater reduction in muscle activation after SCI may relate to a reduced capacity to overcome fast fatigue-related excitability changes at the spinal level.

Low-Intensity Wheelchair Training in Inactive People with Long-Term Spinal Cord Injury: A Randomized Controlled Trial on Propulsion Technique.

OBJECTIVE: The objective of this study was to investigate the effects of a low-intensity wheelchair training on propulsion technique in inactive people with long-term spinal cord injury. DESIGN: Participants in this multicenter nonblinded randomized controlled trial were inactive manual wheelchair users with spinal cord injury for at least 10 yrs (N = 29), allocated to exercise (n = 14) or no exercise. The 16-wk training consisted of wheelchair treadmill propulsion at 30%-40% heart rate reserve or equivalent in rate of perceived exertion, twice a week, 30 mins per session. Propulsion technique was assessed at baseline as well as after 8, 16, and 42 wks during two submaximal treadmill-exercise blocks using a measurement wheel attached to a participant's own wheelchair. Changes over time between the groups were analyzed using Mann-Whitney U tests on difference scores (P < 0.05/3). RESULTS: Data of 16 participants could be analyzed (exercise: n = 8). Significant differences between the exercise and control groups were only found in peak force after 8 wks (respective medians, -20 N vs. 1 N; P = 0.01; r(u) = 0.78). CONCLUSIONS: Significant training effects on propulsion technique were not found in this group. Perhaps, substantial effects require a higher intensity or frequency. Investigating whether more effective and feasible interventions exist might help reduce the population's risk of upper-body joint damage during daily wheelchair propulsion.

Wheelchair-specific fitness of inactive people with long-term spinal cord injury.

OBJECTIVES: To describe wheelchair-specific anaerobic work capacity, isometric strength and peak aerobic work capacity of physically inactive people with long-term spinal cord injury using outcomes of tests that are feasible for use in rehabilitation centres, and to determine associations among these fitness components. DESIGN: Cross-sectional study. PARTICIPANTS: Manual wheelchair users with spinal cord injury for at least 10 years, who were inactive based on a norm score of a physical activity questionnaire (n = 29; 22 men; 20 with paraplegia; median age 53 years). METHODS: Participants performed 3 exercise tests in their own wheelchair to determine: highest 5-s power output over 15-m overground sprinting (P5-15m); highest 3-s isometric push-force (Fiso); and peak power output (POpeak) and peak oxygen uptake (VO2peak) over a peak test. RESULTS: Median (interquartile range) was in P5-15m 16.1 W (9.4-20.9); in Fiso 399 N (284-610); in POpeak 40.9 W (19.1-54.9); and in VO2peak 1.26 l/min (0.80-1.67). Correlations among outcomes of fitness components were weak (r = 0.50-0.67, p < 0.01), except for P5-15m with POpeak (r = 0.79, p < 0.001). CONCLUSION: All fitness components measured in this sample were at relatively low levels, implying a specific need for interventions to improve wheelchair-specific fitness. The weak-to-moderate associations among components imply that separate tests should be used when monitoring wheelchair-specific fitness in rehabilitation centres.

WHEEL-I: development of a wheelchair propulsion laboratory for rehabilitation.

OBJECTIVE: To describe the enabling factors and barriers experienced in the Wheelchair Expert Evaluation Laboratory - implementation (WHEEL-i) project, in which scientific knowledge, tools and associated systematic analyses of hand-rim wheelchair propulsion technique, user's wheelchair propulsion capacity, wheelchair-user interface, and wheelchair mechanics were implemented in 2 rehabilitation centres. DESIGN: Implementation project. PATIENTS: Spinal cord injury. METHODS: In this implementation project standardized tests were performed: wheelchair skills tests, 2 questionnaires, and a steady-state exercise test on a treadmill in which propulsion technique (forces and torques) and physical strain (oxygen uptake, heart rate and mechanical efficiency) were measured. RESULTS: Good interpretation of the test outcomes was the most important barrier. In order to discuss individual wheelchair performance results with patients and clinicians, reference data were developed, smallest detectable differences were calculated and software was developed to simultaneously show video recordings and force and torque signals. CONCLUSION: Based on pilot results, the greatest barrier to systematic monitoring of the individual wheelchair fitting and learning process in rehabilitation with, among others, instrumented measurement wheels, was interpretation of outcomes. For proper interpretation of individual outcomes, the availability of reference data, smallest detectable differences and visualization of outcomes is of utmost importance.

Motor imagery ability in stroke patients: the relationship between implicit and explicit motor imagery measures.

There is little consensus on how motor imagery ability should be measured in stroke patients. In particular it is unclear how two methods tapping different aspects of the motor imagery process relate to each other. The aim of this study was to investigate the relationship between implicit and explicit motor imagery ability by comparing performance of stroke patients and controls on a motor imagery questionnaire and a hand laterality judgment task (HLJT). Sixteen ischemic stroke patients (36 ± 13 weeks post-stroke) and 16 controls, matched by age (51 ± 10 years), gender (7 females) and handedness (3 left-handed), performed a HLJT and completed a motor imagery questionnaire. Our study shows that neither in the healthy controls nor in patients, a correlation is found between the HLJT and the motor imagery questionnaire. Although the patient group scored significantly lower than the control group on the visual motor imagery component (U = 60; p = 0.010) and the kinesthetic motor imagery component (U = 63.5; p = 0.015) of the questionnaire, there were no significant differences between patients and controls on accuracy scores of the HLJT. Analyses of the reaction time profiles of patients and controls showed that patient were still able to use an implicit motor imagery strategy in the HLJT task. Our results show that after stroke performance on tests that measure two different aspects of motor imagery ability, e.g., implicit and explicit motor imagery, can be differently affected. These results articulate the complex relation phenomenological experience and the different components of motor imagery have and caution the use of one tool as an instrument for use in screening, selecting and monitoring stroke patients in rehabilitation settings.

Secondary health conditions in persons with spinal cord injury: a longitudinal study from one to five years post-discharge.

OBJECTIVE: To assess the occurrence of secondary health conditions and their potential risk factors in persons with spinal cord injury from 1 to 5 years after discharge from initial inpatient rehabilitation. DESIGN: Multicentre longitudinal study. SUBJECTS: A total of 139 wheelchair-dependent persons with spinal cord injury. METHODS: The occurrence of secondary health conditions and their potential risk factors were assessed in a clinical interview with a rehabilitation physician at 1 and 5 years after discharge from inpatient rehabilitation and by a telephone interview 2 years after discharge. Self-report questionnaires were used for the assessment of musculoskeletal and neuropathic pain. RESULTS: Neuropathic pain (83.7-92.1%), musculoskeletal pain (62.3-87.1%) and urinary tract infection (56.5-58.9%) were the most frequently reported secondary health conditions. The occurrence of several secondary health conditions was higher among women and individuals with a complete lesion, tetraplegia, and with a higher body mass index. CONCLUSION: Secondary health conditions are common in the first years post-discharge following spinal cord injury, and their course seems to be relatively stable. These results emphasize the number of health issues that must be considered during post-injury care of persons with spinal cord injury living in the community, and the importance of a well-coordinated interdisciplinary approach from specialized rehabilitation centres.

Using the Hand Laterality Judgement Task to assess motor imagery: a study of practice effects in repeated measurements.

The aim of this study was to determine whether there is a practice effect on the Hand Laterality Judgement Task (HLJT). The HLJT task is a mental rotation task that can be used to assess motor imagery ability in stroke patients. Thirty-three healthy individuals performed the HLJT and two control tasks twice at a 3-week interval. Differences in the accuracy and the response times were analysed. The results for all three tasks showed a decrease in the response time between the first and the second assessments (8-20%), and, for the HLJT, also a small (3%) but relevant increase in accuracy. The most likely factor explaining this improvement is that of practice effects. This implies that an improvement in the HLJT scores found over time in clinical research may be partly because of a learning effect, which has to be taken into account when interpreting the results. It is likely that a practice effect occurs in repeated measurements of the HLJT.

Recovery of motor imagery ability in stroke patients.

Objective. To investigate whether motor imagery ability recovers in stroke patients and to see what the relationship is between different types of imagery and motor functioning after stroke. Methods. 12 unilateral stroke patients were measured at 3 and 6 weeks poststroke on 3 mental imagery tasks. Arm-hand function was evaluated using the Utrecht Arm-Hand task and the Brunnström Fugl-Meyer Scale. Age-matched healthy individuals (N = 10) were included as controls. Results. Implicit motor imagery ability and visual motor imagery ability improved significantly at 6 weeks compared to 3 weeks poststroke. Conclusion. Our study shows that motor imagery can recover in the first weeks after stroke. This indicates that a group of patients who might not be initially selected for mental practice can, still later in the rehabilitation process, participate in mental practice programs. Moreover, our study shows that mental imagery modalities can be differently affected in individual patients and over time.