Prognosis of Pain after Stroke during Rehabilitation Depends on the Pain Quality.

OBJECTIVE: Pain after a stroke interferes with daily life and the rehabilitation process. This study aimed to clarify the prognosis of pain in subgroups of patients with pain after a stroke using pain quality data. METHODS: The study included 85 patients with pain after stroke undergoing exercise-based rehabilitation. Items of the Neuropathic Pain Symptom Inventory (NPSI) were used, and patients with pain after stroke were clustered according to their scores of NPSI. Other clinical assessments, such as physical and psychological conditions, were assessed by interviews and questionnaires, and then these were compared among subgroups in a cross-sectional analysis. Longitudinal pain intensity in each subgroup was recorded during 12 weeks after the stroke and the patients' pain prognoses were compared between subgroups. RESULTS: Four distinct subgroups were clustered: cluster 1 (cold-evoked pain and tingling), cluster 2 (tingling only), cluster 3 (pressure-evoked pain), and cluster 4 (deep muscle pain with a squeezing and pressure sensation). The cross-sectional analysis showed varying clinical symptoms among the subgroups, with differences in the prevalence of joint pain, limited range of motion, somatosensory dysfunction, and allodynia. There were no significant differences in pain intensity at baseline among the subgroups. A longitudinal analysis showed divergent prognoses of pain intensity among the subgroups. The pain intensity in cluster 4 was significantly alleviated, which suggested that musculoskeletal pain could be reduced with conventional exercise-based rehabilitation. However, the pain intensity of patients in clusters 1 and 2 remained over 12 weeks. CONCLUSION: The study classified patients into clinically meaningful subgroups using pain quality data and provided insight into their prognosis of pain. The findings could be useful for guiding personalized rehabilitation strategies for pain management. IMPACT: Assessment of pain quality in patients with pain after stroke leads to personalized rehabilitation for pain management.

A comprehensive multivariate analysis of the center of pressure during quiet standing in patients with Parkinson's disease.

BACKGROUND: We hypothesized that postural instability observed in individuals with Parkinson's disease (PD) can be classified as distinct subtypes based on comprehensive analyses of various evaluated parameters obtained from time-series of center of pressure (CoP) data during quiet standing. The aim of this study was to characterize the postural control patterns in PD patients by performing an exploratory factor analysis and subsequent cluster analysis using CoP time-series data during quiet standing. METHODS: 127 PD patients, 47 aged 65 years or older healthy older adults, and 71 healthy young adults participated in this study. Subjects maintain quiet standing for 30 s on a force platform and 23 variables were calculated from the measured CoP time-series data. Exploratory factor analysis and cluster analysis with a Gaussian mixture model using factors were performed on each variable to classify subgroups based on differences in characteristics of postural instability in PD. RESULTS: The factor analysis identified five factors (magnitude of sway, medio-lateral frequency, anterio-posterior frequency, component of high frequency, and closed-loop control). Based on the five extracted factors, six distinct subtypes were identified, which can be considered as subtypes of distinct manifestations of postural disorders in PD patients. Factor loading scores for the clinical classifications (younger, older, and PD severity) overlapped, but the cluster classification scores were clearly separated. CONCLUSIONS: The cluster categorization clearly identifies symptom-dependent differences in the characteristics of the CoP, suggesting that the detected clusters can be regarded as subtypes of distinct manifestations of postural disorders in patients with PD.

Relative contribution of sensory and motor deficits on grip force control in patients with chronic stroke.

OBJECTIVE: This study aimed to characterize grasping behavior in static (weight-dependent modulation and stability of control) and dynamic (predictive control) aspects specifically focusing on the relative contribution of sensory and motor deficits to grip force control in patients with chronic stroke. METHODS: Twenty-four chronic stroke patients performed three manipulative tasks: five trials of 5-s grasp-lift-holding, 30-s static holding, and vertical dynamic/cyclic oscillation of holding the object. RESULTS: Exerted static grip force on the paretic side exhibited statistically greater than that on the non-paretic side. Spearman's rank correlation coefficient revealed that the contribution to static grip force control was larger in sensory deficits than in motor deficits. In addition, the sensory deficit is related to the reduced coupling between grip force and load force, suggesting difficulty in predictive control due to the absence of sensory feedback. CONCLUSIONS: Given that grip force control involves predictive feedforward and online feedback control, the evaluation of grip force might be an important and feasible evaluation manner for the assessment of sensorimotor control in patients post-stroke. SIGNIFICANCE: Detailed evaluation of grip force control would help to understand the mechanisms underlying hand dysfunction in stroke patients.

Characterizing clinical progression in patients with musculoskeletal pain by pain severity and central sensitization-related symptoms.

Central sensitization-related symptoms (CSS) are associated with the severity and progression of pain. The relationship between the severity of pain/CSS and clinical progresses remains unclear. This multicenter, collaborative, longitudinal study aimed to characterize the clinical outcomes of patients with musculoskeletal pain by classifying subgroups based on the severity of pain/CSS and examining changes in subgroups over time. We measured the pain intensity, CSS, catastrophic thinking, and body perception disturbance in 435 patients with musculoskeletal pain. Reevaluation of patients after one month included 166 patients for pain intensity outcome and 110 for both pain intensity and CSS outcome analysis. We classified the patients into four groups (mild pain/CSS, severe pain/mild CSS, severe pain/CSS, and mild pain/severe CSS groups) and performed multiple comparison analyses to reveal the differences between the CSS severity groups. Additionally, we performed the adjusted residual chi-square to identify the number of patients with pain improvement, group transition, changing pain, and CSS pattern groups at baseline. The most characteristic result was that the mild and severe CSS groups showed worsening pain. Moreover, many of the group transitions were to the same group, with a few transitioning to a group with mild pain/CSS. Our findings suggest that the severity and improvement of CSS influence pain prognosis.

I am not the cause of this pain: An experimental study of the cognitive processes underlying causal attribution in the unpredictable situation whether negative outcomes.

OBJECTIVES: Pain causal attribution is the attribution of pain causes to self or others, which may depend on one's choice of actions. The study aimed to examine how the cognitive processes of pain causal attribution as one aspect of the sense of agency change in healthy individuals based on free or forced choice, using a temporal binding (TB) experimental task. METHODS: Participants pressed keys (action) in a combined TB task, with one key having a high probability of delivering pain (with tone). In fact, only the bias between the free-choice and the forced choice conditions was manipulated. Participants estimated the time between their action and tone, with shorter intervals indicating internal attribution. RESULTS: Interval estimation was significantly longer in the forced-choice condition than in the free-choice condition when a pain stimulus was delivered. CONCLUSIONS: Explicit complaints of pain being caused by others may be represented in implicit cognitive processes.

Trends in amount of use to upper limb function in patients with subacute stroke: a cross-sectional study using segmental regression analysis.

BACKGROUND: Hemiparesis affects approximately 33-80% of patients with stroke, and a quarter of these individuals experience difficulty with the voluntary use of their paretic upper limb for performing activities of daily living within five years of stroke onset. Therefore, assessing upper limb functionality and use after a stroke is crucial. The Fugl-Meyer Assessment (FMA) and the Motor Activity Log (MAL) are the two most widely used methods for assessing post-stroke paretic upper limb. While previous research has shown a strong correlation between the FMA of Upper Extremity (FMA-UE) and the MAL scores, to date, no study has investigated the differences in the characteristics and trends of upper extremity usage frequency in the FMA-UE. This study aimed to statistically categorize the FMA-UE scores using segmental regression analysis and identify disparities in the trends of paretic upper extremity utilization frequency in MAL. METHODS: Patients with first-episode subacute stroke were chosen for the cohort study. The primary assessments used were FMA-UE and MAL Amount of Use (MAL-A); age, gender, and time since onset served as secondary assessments. Segmental regression analysis was used, with FMA-UE as the independent variable and MAL-A as the dependent variable. R2 values were calculated using linear and polynomial regression on binary values, and the coefficients of determination were compared using segmental regression analysis. RESULTS: The study included 203 participants with a mean age of 70.1 ± 13.1 years; 113 were male and 90 female. The mean time since onset was 29.2 ± 14.8 days, the mean FMA-UE score was 43.6 ± 22.3 points, and the mean MAL-A score was 2.3 ± 2.0 points. The segmental regression analysis revealed that the inflection point for FMA-UE was 45.3 points, and the slope of the regression line underwent a transformation before and after the inflection point. CONCLUSIONS: This study indicates that the trend in the amount of use of paretic upper limb utilization changes around inflection point 45 in the FMA-UE. These findings could be useful for designing rehabilitation strategies to improve paretic upper limb utilization by increasing exercise duration in patients with subacute stroke.

Eye movement training and gaze analysis for a patient with binocular diplopia after traumatic brain injury: a case report.

BACKGROUND: Patients with traumatic brain injury often develop sequelae such as eye movement disorders, including diplopia. Eye movement training is effective in diplopia management. However, few longitudinal follow-up studies have been conducted from the subacute disease stage, owing to the complexity of methods for quantifying diplopia. CASE PRESENTATION: The patient is a 30-year-old Japanese man who presented with diplopia and underwent eye movement training for approximately 4 weeks. The angle of diplopia, distance of abduction of the eye, gaze analysis, and self-assessment of diplopia using Holmes' diplopia questionnaire were evaluated. The degree of diplopia increased from 12° to 40° on the right side. The distance of eye abduction increased from 10.4 to 12.8 mm. The self-assessment score improved from 76 to 12 points. Analysis of gaze transition revealed a reduction in the error between the target and gaze. CONCLUSION: Eye movement training was successful in ameliorating the symptoms of diplopia in the patient with binocular diplopia. Furthermore, for patients with diplopia symptoms, it was suggested that the oculomotor approach to eye movement training should not only focus on the direction of the diplopia but also on the direction opposite to the diplopia (the weak side).

Action-outcome Regularity Perceptual Sensitivity in Children with Developmental Coordination Disorder.

PURPOSE: An internal model deficit is considered to underlie developmental coordination disorder (DCD); thus, children with DCD have an altered sense of agency (SoA), which is associated with depressive symptoms. Furthermore, the perception of action-outcome regularity is present in early development, is involved in the generation of SoA, and has roles in adaptive motor learning and coordinated motor skills. However, perceptual sensitivity to action-outcome regularity has not been examined in children with DCD. METHODS: We investigated perceptual sensitivity to action-outcome regularity in 6-15-year-old children with DCD and age- and sex-matched typically developing (TD) children. Both groups were assessed for coordinated motor skills with the Movement Assessment Battery for Children-2nd Edition, while the DCD group was assessed with the DCD Questionnaire, Social Communication Questionnaire, Attention-Deficit/Hyperactivity Disorder-Rating Scale, and Depression Self- Rating Scale for Children. RESULTS: Perceptual sensitivity to action-outcome regularity was significantly reduced in children with DCD. However, there was a significant correlation between perceptual sensitivity to action-outcome regularity and age in DCD and TD children. Perceptual sensitivity to action-outcome regularity was significantly lower in younger children with DCD than in younger and older TD children, but there were no significant differences between older children with DCD and younger and older TD children. CONCLUSION: The current results suggest that children with DCD have significantly reduced perceptual sensitivity to action-outcome regularity at younger ages, which may alter SoA and inhibit internal model development, thereby reducing motor skill coordination.

Effect of bihemispheric transcranial direct current stimulation on distal upper limb function and corticospinal tract excitability in a patient with subacute stroke: a case study.

Introduction: Activation of the unaffected hemisphere contributes to motor function recovery post stroke in patients with severe upper limb motor paralysis. Transcranial direct current stimulation (tDCS) has been used in stroke rehabilitation to increase the excitability of motor-related areas. tDCS has been reported to improve upper limb motor function; nonetheless, its effects on corticospinal tract excitability and muscle activity patterns during upper limb exercise remain unclear. Additionally, it is unclear whether simultaneously applied bihemispheric tDCS is more effective than anodal tDCS, which stimulates only one hemisphere. This study examined the effects of bihemispheric tDCS training on corticospinal tract excitability and muscle activity patterns during upper limb movements in a patient with subacute stroke. Methods: In this single-case retrospective study, the Fugl-Meyer Assessment, Box and Block Test, electromyography, and intermuscular coherence measurement were performed. Intermuscular coherence was calculated at 15-30 Hz, which reflects corticospinal tract excitability. Results: The results indicated that bihemispheric tDCS improved the Fugl-Meyer Assessment, Box and Block Test, co-contraction, and intermuscular coherence results, as compared with anodal tDCS. Discussion: These results reveal that upper limb training with bihemispheric tDCS improves corticospinal tract excitability and muscle activity patterns in patients with subacute stroke.

Shared decision-making in physiotherapy: a cross-sectional study of patient involvement factors and issues in Japan.

BACKGROUND: Evidence-based medicine education has not focused on how clinicians involve patients in decision-making. Although shared decision-making (SDM) has been investigated to address this issue, there are insufficient data on SDM in physiotherapy. This study aimed to clarify the issues concerning patient involvement in Japan, and to examine whether SDM is related to perceptions of patient involvement in decision-making. METHODS: The study participants were recruited from among acute and sub-acute inpatients and community residents receiving physiotherapy outpatient care, day care, and/or home rehabilitation. The Control Preference Scale (CPS) was used to measure the patients' involvement in decision-making. The nine-item Shared Decision-Making Questionnaire (SDM-Q-9) was used to measure SDM. In analysis I, we calculated the weighted kappa coefficient to examine the congruence in the CPS between the patients' actual and preferred roles. In analysis II, we conducted a logistic regression analysis using two models to examine the factors of patient involvement. RESULTS: Analysis I included 277 patients. The patients' actual roles were as follows: most active (4.0%), active (10.8%), collaborative (24.6%), passive (35.0%), and most passive (25.6%). Their preferred roles were: most active (3.3%), active (18.4%), collaborative (39.4%), passive (24.5%), and most passive (14.4%). The congruence between actual and preferred roles by the kappa coefficient was 0.38. Analysis II included 218 patients. The factors for patient involvement were the clinical environment, the patient's preferred role, and the SDM-Q-9 score. CONCLUSIONS: The patients in Japan indicated a low level of decision-making involvement in physiotherapy. The patients wanted more active involvement than that required in the actual decision-making methods. The physiotherapist's practice of SDM was revealed as one of the factors related to perceptions of patient involvement in decision-making. Our results demonstrated the importance of using SDM for patient involvement in physiotherapy.

Characteristics of uneven surface walking in stroke patients: Modification in biomechanical parameters and muscle activity.

BACKGROUND: Stroke patients have difficulty walking in outdoor environments, including uneven surfaces, reducing their opportunities for social participation. Changes in stroke patients' gait while walking on even surfaces have been reported; however, gait alterations on uneven surfaces remain unclear. RESEARCH QUESTION: To what extent do biomechanical parameters and muscle activity during even and uneven surface walking differ between stroke patients and healthy people? METHODS: Twenty stroke patients and 20 age-matched healthy people walked on a 6 m even and uneven surfaces. Data on gait speed, root mean square (RMS) of trunk acceleration as a measure of gait stability, maximum joint angle, average muscle activity, and muscle activity time were quantified using accelerometers attached to the trunk, video camera images, and electromyography of lower extremities. A two-factor mixed-model analysis of variance was used to test the effects of group, surface, and group × surface interactions. RESULTS: Gait speed decreased (p < 0.001) on the uneven surface in stroke patients and healthy people. RMS showed an interaction (p < 0.001), and the post-hoc test revealed an increase in stroke patients in the mediolateral direction during the swing phase on the uneven surface. The hip extension angle during the stance phase showed an interaction (p = 0.023), and the post-hoc test revealed a decrease in stroke patients on the uneven surface. The soleus muscle activity time showed an interaction during the swing phase (p = 0.041), and the post-hoc test revealed an increase in stroke patients compared to healthy people only on the uneven surface. SIGNIFICANCE: While walking on an uneven surface, stroke patients showed decreased gait stability, decreased hip extension angle during stance phase, and increased ankle plantar flexor activity time during swing phase. These changes may result from impaired motor control and compensatory strategies used by stroke patients on uneven surfaces.

Effect of disturbance stimulation using a split-belt treadmill on a patient with cerebellar ataxia: a case report.

PURPOSE: We present the case of a patient with cerebellar ataxia who was treated with walking practice using a split-belt treadmill with disturbance stimulation. The treatment effects were evaluated for improvements in standing postural balance and walking ability. CASE PRESENTATION: The patient was a 60-year-old Japanese male who developed ataxia after cerebellar hemorrhage. Assessment was performed using the Scale for the Assessment and Rating of Ataxia, Berg Balance Scale, and Timed Up-and-Go tests. A 10 m walking speed and walking rate were also assessed longitudinally. The obtained values were fit into a linear equation (y = ax + b), and the slope was calculated. This slope was then used as the predicted value for each period relative to the pre-intervention value. After removing the trend of the value for each period relative to the pre-intervention value, the amount of pre- to post-intervention change for each period was calculated to verify the intervention effect. Furthermore, to verify the changes in gait over time, a three-dimensional motion analyzer was used to analyze the pre- and post-intervention gait five times, and the results were kinematically compared. RESULTS: No significant pre- to post-intervention changes were observed in the Scale for the Assessment and Rating of Ataxia scores. Conversely, the Berg Balance Scale score, walking rate, and 10 m walking speed increased, and the Timed Up-and-Go score decreased in the B1 period, indicating a marked improvement from the predicted results based on the linear equation. For changes in gait determined using three-dimensional motion analysis, an increase in stride length was observed in each period. CONCLUSION: The present case findings suggest that walking practice with disturbance stimulation using a split-belt treadmill does not improve inter-limb coordination, but contributes to improving standing posture balance, 10 m walking speed, and walking rate.

Adaptability of the Sense of Agency in Healthy Young Adults in Sensorimotor Tasks for a Short Term.

Sense of agency (SoA) refers to the subjective feeling of controlling one's own actions and sensory feedback. The SoA occurs when the predicted feedback matches the actual sensory feedback and is responsible for maintaining behavioral comfort. However, sensorimotor deficits because of illness cause incongruence between prediction and feedback, so the patient loses comfort during actions. Discomfort with actions associated with incongruence may continue robustly (i.e., "not" adaptable) throughout life because of the aftereffects of the disease. However, it is unclear how the SoA modulates when incongruency is experienced, even for a short term. The purpose of this study was to investigate the adaptability of the SoA in healthy participants in sensorimotor tasks for a short term. Participants were divided into congruent and incongruent exposure groups. The experimental task of manipulating the ratio of the self-control of a PC cursor was used to measure the SoA before and after exposure to congruent or incongruent stimuli. The results showed no significant differences between the groups before and after exposure for a short term. The finding that the SoA was not adaptable may assist in guiding the direction of future studies on how to correct incongruence.

Anticipatory postural adjustments mediate the changes in fear-related behaviors in individuals with chronic low back pain.

OBJECTIVES: The role(s) of anticipatory postural adjustments (APAs) in changes in subsequent motor and postural controls in response to movement perturbations are unclear in individuals with chronic low back pain (CLBP). This study aimed to clarify the relationships among kinesiophobia, APAs, lumbar kinematic output, and postural control associated with lumbar movement in individuals with CLBP. METHODS: CLBP participants (n=48) and healthy controls (HCs) without CLBP (n=22) performed a bend-forward task using their lumbar region on a force platform and returned upright. Each participant's lumbar movements were recorded using an electrogoniometer. We calculated the APA duration, the duration of lumbar direction changes from forward to backward, and the center of pressure (COP) position after lumbar movement tasks completion. RESULTS: Compared with the HCs, the duration of direction changes in lumbar movement and the APA duration in CLBP participants were prolonged, and the COP position was shifted forward. The mediation analysis revealed that the duration of lumbar direction changes in the CLBP group was subjected to a significant indirect effect of APAs and a direct effect of kinesiophobia, and the COP position was subjected to a significant indirect effect of kinesiophobia through APAs. CONCLUSIONS: APAs partially mediate the relationship between kinesiophobia and changes in lumbar motor control and mediate the relationship between kinesiophobia and postural control in response to movement perturbations. These findings expand our understanding of APAs in altered subsequent movement and postural controls due to kinesiophobia in individuals with CLBP.

Influence of vibrotactile random noise on the smoothness of the grasp movement in patients with chemotherapy-induced peripheral neuropathy.

Patients with chemotherapy-induced peripheral neuropathy (CIPN) often suffer from sensorimotor dysfunction of the distal portion of the extremities (e.g., loss of somatosensory sensation, numbness/tingling, difficulty typing on a keyboard, or difficulty buttoning/unbuttoning a shirt). The present study aimed to reveal the effects of subthreshold vibrotactile random noise stimulation on sensorimotor dysfunction in CIPN patients without exacerbating symptoms. Twenty-five patients with CIPN and 28 age-matched healthy adults participated in this study. To reveal the effects of subthreshold vibrotactile random noise stimulation on sensorimotor function, participants were asked to perform a tactile detection task and a grasp movement task during random noise stimulation delivered to the volar and dorsal wrist. We set three intensity conditions of the vibrotactile random noise: 0, 60, and 120% of the sensory threshold (Noise 0%, Noise 60%, and Noise 120% conditions). In the tactile detection task, a Semmes-Weinstein monofilament was applied to the volar surface of the tip of the index finger using standard testing measures. In the grasp movement task, the distance between the thumb and index finger was recorded while the participant attempted to grasp a target object, and the smoothness of the grasp movement was quantified by calculating normalized jerk in each experimental condition. The experimental data were compared using two-way repeated-measures analyses of variance with two factors: experimental condition (Noise 0, 60, 120%) × group (Healthy controls, CIPN patients). The tactile detection threshold and the smoothness of the grasp movement were only improved in the Noise 60% condition without exacerbating numbness/tingling in CIPN patients and healthy controls. The current study suggested that the development of treatment devices using stochastic resonance can improve sensorimotor function for CIPN patients.

Changes in Standing Postural Control Ability in a Case of Spinocerebellar Ataxia Type 31 With Physical Therapy Focusing on the Center of Gravity Sway Variables and Lower Leg Muscle Activity.

Spinocerebellar degeneration (SCD) is a progressive disease characterized by cerebellar ataxia or the posterior spinal cord. Among these, spinocerebellar ataxia type 31 (SCA31) is genetically more common in the Japanese population and is characterized by pure ataxia, resulting in severe disturbances in postural balance, with common falls. Therefore, rehabilitation is important to improve postural balance. Light touch is a known method of reducing postural sway, which acts with the light touching of an object with the body. We herein present a case of a patient with SCA31 who was trained in a standing position by lightly touching the back of the body to a wall surface. Dynamic interarticular coordination exercises were also performed as part of the rehabilitation program. As a result, even in the progressive SCA31, improvements in standing postural balance and activities of daily living contributed to improvements in the patient's postural balance. We followed the progress of postural control ability using the center of gravity sway measurement and electromyography and described some interesting characteristics of the patient's postural control ability in this report.

Effects of Vibration-Based Generation of Timing of Tactile Perception on Upper Limb Function After Stroke: A Case Study.

Sensorimotor dysfunction of the fingers and hands hinders the recovery of motor function post-stroke. Generally, hemiplegic patients are unable to properly control the dynamic friction generated between their fingers and objects during hand/finger muscle activity. In addition to sensory information, a sense of agency generated by the temporal synchronization of sensory prediction and sensory feedback is required to control this dynamic friction. In the present study, we utilized a novel rehabilitation device that transmits real-time fingertip contact information to a transducer in a case of stroke hemiplegia with sensorimotor deficits and stagnated hand/finger motor performance. Post-intervention, the patient's upper extremity motor function score (FMA-UE), which had previously been in a state of arrested recovery, improved from 51/66 to 61/66, especially in the wrist joints. Excessive grip force during object grasping and frequency of falling objects was notably decreased post-intervention. We believe that rehabilitation tasks using perceptual generation via transducer will be a new tool for the rehabilitation of post-stroke hand/finger sensorimotor deficits.

Developmental changes in action-outcome regularity perceptual sensitivity and its relationship to hand motor function in 5-16-year-old children.

Along with the comparator model, the perception of action-outcome regularity is involved in the generation of sense of agency. In addition, the perception of action-outcome regularity is related to motor performance. However, no studies have examined the developmental changes in the perception of action-outcome regularity. The current study measured perceptual sensitivity to action-outcome regularity and manual dexterity in 200 children aged between 5 and 16 years. The results showed that perceptual sensitivity to action-outcome regularity was significantly lower in 5-6-year-old children than in 9-16-year-old children, and that it was significantly lower in children with low manual dexterity than in children with medium to high manual dexterity. Correlation analyses revealed significant correlations of age and perceptual sensitivity to action-outcome regularity, but no significant correlation of manual dexterity and perceptual sensitivity to action-outcome regularity, either overall or in any age band. The present study suggests that perceptual sensitivity to action-outcome regularity is immature at 5-6 years of age and that it may be impaired in 5-16-year-old children with poor manual dexterity.

Changes in task-specific fear of movement and impaired trunk motor control by pain neuroscience education and exercise: A preliminary single-case study of a worker with low back pain.

We report a case (a worker with low back pain) who was provided patient education and therapeutic exercise, and we performed a detailed kinematic analysis of his work-related activity over time. The subjects were one 28-year-old male worker with low back pain. In addition, to clearly identify impaired trunk movement during work-related activity in the low back pain subject, 20 age-matched healthy males (control group) were also included as a comparison subject. He received pain neurophysiology education and exercise instruction. We analyzed the subject's trunk movement pattern during a lifting task examined by a three-dimensional-motion capture system. In addition, task-specific fear that occurred during the task was assessed by the numerical rating scale. The assessment was performed at the baseline phase (4 data points), the intervention phase (8 data points), and the follow-up phase (8 data points), and finally at 3 and 8 months after the follow-up phase. No intervention was performed in the control group; they underwent only one kinematic evaluation at baseline. As a result, compared to the control group, the low back pain subject had slower trunk movement velocity (peak trunk flexion velocity = 50.21 deg/s, extension velocity = -47.61 deg/s), and his upper-lower trunk segments indicated an in-phase motion pattern (mean absolute relative phase = 15.59 deg) at baseline. The interventions reduced his pain intensity, fear of movement, and low back pain-related disability; in addition, his trunk velocity was increased (peak trunk flexion velocity = 82.89 deg/s, extension velocity = -77.17 deg/s). However, the in-phase motion pattern of his trunk motor control remained unchanged (mean absolute relative phase = 16.00 deg). At 8 months after the end of the follow-up, the subject's in-phase motion pattern remained (mean absolute relative phase = 13.34 deg) and his pain intensity had increased. This report suggests that if impaired trunk motor control remains unchanged after intervention, as in the course of the low back pain subject, it may eventually be related to a recurrence of low back pain symptoms.