Alteration in coracohumeral ligament and distance in people with symptoms of subcoracoid impingement.

BACKGROUND: Differentiation between subacromial impingement versus subcoracoid impingement are important for the treatment target. We evaluated the correlations between coracohumeral ligament (CHL) thickness and distance (CHD) and characterized the CHL and subscapularis (SSC) in subcoracoid impingement subjects. METHODS: An observational, cross-sectional study was carried out. Twenty subcoracoid impingement subjects and age/gender matched controls were assessed in 4 different shoulder positions by ultrasonography. RESULTS: Moderate correlations between CHL thickness with CHD (r = 0.455 in neutral rotation, p = 0.044; r = 0.483 in interior rotation, p = 0.031) were found in subacromial subjects. Subcoracoid impingement subjects had greater CHL thickness (difference = 0.3 mm, effect size = 0.85, p = 0.006), SSC tendon thickness (difference = 0.7 mm, effect size = 0.92, p = 0.01) and SSC/CHD occupation ratio (difference = 8%, effect size = 0.95, p = 0.005) compared with the control. CONCLUSIONS: Coracohumeral distance is related to ligament thickness, especially in subacromial impingement subjects. Increased coracohumeral ligament and subscapularis thickness as well as decreased subscapularis/coracohumeral distance occupation ratio are characterized in subcoracoid impingement subjects. These quantitative measurements can be useful in identifying patients at risk of subcoracoid impingement from subacromial impingement.

Effects of Extracorporeal Shock Wave-Mediated Transdermal Local Anesthetic Drug Delivery on Rat Caudal Nerves.

Cavitation plays a substantial role in the clinical effects of extracorporeal shock wave therapy (ESWT). It is also generally accepted as a major mechanism in sonophoresis. To identify the enhancing effect of extracorporeal shock wave-mediated transdermal drug delivery, 24 Wistar rats were randomly assigned to four groups: (i) topical application of a eutectic mixture of local anesthetics (EMLA); (ii) 1-MHz ultrasound; (iii) ESWT pre-treatment combined with EMLA application; (iv) ESWT concurrent with EMLA application on rat tails. The degree of anesthesia was assessed using the amplitude and latency of sensory nerve action potentials within 5 min after a 60-min EMLA application. The results indicated that ESWT pre-treatment and concurrent ESWT accelerated the anesthetic effects of the EMLA cream on the tail nerve (p < 0.05). This finding might indicate that shock wave-mediated transdermal drug delivery is possible during the ESWT period.

Immediate Effects of Clock-Turn Strategy on the Pattern and Performance of Narrow Turning in Persons With Parkinson Disease.

BACKGROUND AND PURPOSE: Turning difficulty is common in people with Parkinson disease (PD). The clock-turn strategy is a cognitive movement strategy to improve turning performance in people with PD despite its effects are unverified. Therefore, this study aimed to investigate the effects of the clock-turn strategy on the pattern of turning steps, turning performance, and freezing of gait during a narrow turning, and how these effects were influenced by concurrent performance of a cognitive task (dual task). METHODS: Twenty-five people with PD were randomly assigned to the clock-turn or usual-turn group. Participants performed the Timed Up and Go test with and without concurrent cognitive task during the medication OFF period. The clock-turn group performed the Timed Up and Go test using the clock-turn strategy, whereas participants in the usual-turn group performed in their usual manner. Measurements were taken during the 180° turn of the Timed Up and Go test. The pattern of turning steps was evaluated by step time variability and step time asymmetry. Turning performance was evaluated by turning time and number of turning steps. The number and duration of freezing of gait were calculated by video review. RESULTS: The clock-turn group had lower step time variability and step time asymmetry than the usual-turn group. Furthermore, the clock-turn group turned faster with fewer freezing of gait episodes than the usual-turn group. Dual task increased the step time variability and step time asymmetry in both groups but did not affect turning performance and freezing severity. DISCUSSION AND CONCLUSIONS: The clock-turn strategy reduces turning time and freezing of gait during turning, probably by lowering step time variability and asymmetry. Dual task compromises the effects of the clock-turn strategy, suggesting a competition for attentional resources.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A141).

Motion analysis of axial rotation and gait stability during turning in people with Parkinson's disease.

BACKGROUND: Axial rigidity and postural instability in people with Parkinson's disease (PD) may contribute to turning difficulty. This study examined the rotation of axial segments and gait instability during turning in people with PD. METHODS: Thirteen PD and twelve age-matched healthy adults were recruited. Participants performed the timed Up-and-Go test and were recorded by a 3D motion capture system. Axial rotation was evaluated by the rotation onset of the head, thorax and pelvis. Gait stability was evaluated by the center of mass and center of pressure inclination angle. Turning performance was evaluated by turning time and turning steps. RESULTS: During turning, PD adults rotated the head, thorax and pelvis simultaneously, whereas healthy adults rotated in a cranial to caudal sequence. Further, PD adults had a smaller sagittal inclination angle (p<0.001) but larger frontal inclination angle (p=0.006) than healthy adults. PD adults also turned slower (p=0.002) with a greater number of steps (p<0.001) than healthy adults. Last, PD adults showed a significant correlation between the sagittal inclination angle and turning steps (Spearman's ρ=-0.63), while healthy adults showed a significant correlation between frontal inclination angle and turning steps (Spearman's ρ=-0.67). CONCLUSION: This study demonstrated the axial rigidity in PD adults during turning may reduce forward progression and increase lateral instability. The reduced progression is associated with extra turning steps and the increased lateral instability may result in great fall risk.

Home-based virtual reality balance training and conventional balance training in Parkinson's disease: A randomized controlled trial.

BACKGROUND/PURPOSE: Virtual reality has the advantage to provide rich sensory feedbacks for training balance function. This study tested if the home-based virtual reality balance training is more effective than the conventional home balance training in improving balance, walking, and quality of life in patients with Parkinson's disease (PD). METHODS: Twenty-three patients with idiopathic PD were recruited and underwent twelve 50-minute training sessions during the 6-week training period. The experimental group (n = 11) was trained with a custom-made virtual reality balance training system, and the control group (n = 12) was trained by a licensed physical therapist. Outcomes were measured at Week 0 (pretest), Week 6 (posttest), and Week 8 (follow-up). The primary outcome was the Berg Balance Scale. The secondary outcomes included the Dynamic Gait Index, timed Up-and-Go test, Parkinson's Disease Questionnaire, and the motor score of the Unified Parkinson's Disease Rating Scale. RESULTS: The experimental and control groups were comparable at pretest. After training, both groups performed better in the Berg Balance Scale, Dynamic Gait Index, timed Up-and-Go test, and Parkinson's Disease Questionnaire at posttest and follow-up than at pretest. However, no significant differences were found between these two groups at posttest and follow-up. CONCLUSION: This study did not find any difference between the effects of the home-based virtual reality balance training and conventional home balance training. The two training options were equally effective in improving balance, walking, and quality of life among community-dwelling patients with PD.

Multi-muscle coordination during a challenging stance.

PURPOSE: This study aimed to identify the muscle synergies during standing under various sensory contexts in healthy young adults. METHODS: Sixteen healthy young adults participated in this study. The 4-min stance task was conducted under vision (eyes open or eyes closed) and proprioception (standing on ground or narrowed blocks) manipulated contexts. Electromyography (EMG) of 8 muscles around the right side of the trunk and leg were recorded and submitted to principal component analysis (PCA) to extract the muscle synergies. Two-way ANOVA with repeated measures was employed to test the effect of sensory contexts on the muscle synergies. RESULTS: PCA extracted three muscle synergies that accounted for the variance of standing EMG, including the push-back (composed of medial gastrocnemius, vastus medialis and biceps femoris), push-forward (composed of tibialis anterior and rectus femoris) and proximal mixed (composed of rectus abdominis, rector spinae, rectus femoris and biceps femoris) synergies. Block-standing increased the contribution of the push-back synergy while decreased the contribution of the push-forward synergy. In addition, contribution of the proximal mixed synergy was higher under ground-standing with eyes open than under block-standing with eyes open. CONCLUSION: Three muscle synergies were identified during standing in healthy young adults, and the synergies were affected by proprioception but not visual disturbance. The push-back and push-forward synergies showed the opposite response to proprioceptive disturbance, which may result from their antagonism role. Whether this control regime is used for elderly adults or patient populations with movement disorder needs to be further investigated.

Bidirectional and multi-user telerehabilitation system: clinical effect on balance, functional activity, and satisfaction in patients with chronic stroke living in long-term care facilities.

BACKGROUND: The application of internet technology for telerehabilitation in patients with stroke has developed rapidly. OBJECTIVE: The current study aimed to evaluate the effect of a bidirectional and multi-user telerehabilitation system on balance and satisfaction in patients with chronic stroke living in long-term care facilities (LTCFs). METHOD: This pilot study used a multi-site, blocked randomization design. Twenty-four participants from three LTCFs were recruited, and the participants were randomly assigned into the telerehabilitation (Tele) and conventional therapy (Conv) groups within each LTCF. Tele group received telerehabilitation but the Conv group received conventional therapy with two persons in each group for three sessions per week and for four weeks. The outcome measures included Berg Balance Scale (BBS), Barthel Index (BI), and the telerehabilitation satisfaction of the participants. SETTING: A telerehabilitation system included "therapist end" in a laboratory, and the "client end" in LTCFs. The conventional therapy was conducted in LTCFs. RESULTS: Training programs conducted for both the Tele and Conv groups showed significant effects within groups on the participant BBS as well as the total and self-care scores of BI. No significant difference between groups could be demonstrated. The satisfaction of participants between the Tele and the Conv groups also did not show significant difference. CONCLUSIONS: This pilot study indicated that the multi-user telerehabilitation program is feasible for improving the balance and functional activity similar to conventional therapy in patients with chronic stroke living in LTCFs.

Altered Co-contraction of Cervical Muscles in Young Adults with Chronic Neck Pain during Voluntary Neck Motions.

[Purpose] Muscle co-contraction is important in stabilizing the spine. The aim of this study was to compare cervical muscle co-contraction in adults with and without chronic neck pain during voluntary movements. [Subjects and Methods] Surface electromyography of three paired cervical muscles was measured in fifteen young healthy subjects and fifteen patients with chronic neck pain. The subjects performed voluntary neck movements in the sagittal and coronal plane at slow speed. The co-contraction ratio was defined as the normalized integration of the antagonistic electromyography activities divided by that of the total muscle activities. [Results] The results showed that the co-contraction ratio of patients was greater during flexion movement, lesser during extension movement, slightly greater during right lateral bending, and slightly lesser during left lateral bending compared with in the controls. [Conclusion] The results suggested that neck pain patients exhibit greater antagonistic muscle activity during flexion and dominate-side bending movements to augment spinal stability, while neuromuscular control provides relatively less protection in the opposite movements. This study helps to specify the changes of the stiffness of the cervical spine in neck pain patients and provides a useful tool and references for clinical assessment of neck disorders.

Effect of a combination of whole-body vibration and low resistance jump training on neural adaptation.

This study investigated and compared the effects of an eight-week program of whole body vibration combined with counter-movement jumping (WBV + CMJ) or counter-movement jumping (CMJ) alone on players. Twenty-four men's volleyball players of league A or B were randomized to the WBV + CMJ or CMJ groups (n = 12 and 12; mean [SD] age of 21.4 [2.2] and 21.7 [2.2] y; height of 175.6 [4.6] and 177.6 [3.9] cm; and weight, 69.9 [12.8] and 70.5 [10.7] kg, respectively). The pre- and post-training values of the following measurements were compared: H-reflex, first volitional (V)-wave, rate of electromyography rise (RER) in the triceps surae and absolute rate of force development (RFD) in plantarflexion and vertical jump height. After training, the WBV + CMJ group exhibited increases in H reflexes (p = 0.029 and <0.001); V-wave (p < 0.001); RER (p = 0.003 and <0.001); jump height (p < 0.001); and RFD (p = 0.006 and <0.001). The post-training values of V wave (p = 0.006) and RFD at 0-50 (p = 0.009) and 0-200 ms (p = 0.008) in the WBV + CMJ group were greater than those in the CMJ group. This study shows that a combination of WBV and power exercise could impact neural adaptation and leads to greater fast force capacity than power exercise alone in male players.

Use of motor abundance in old adults in the regulation of a narrow-based stance.

PURPOSE: The ability to maintain stable balance while standing decreases with age. The body must coordinate multiple joints using "freeze" or "free" strategy, or a combination of both to ensure balance stability. The purpose of this study was to examine age-related changes in the use of motor abundance during upright stance on a narrow base without visual input. METHODS: Uncontrolled manifold (UCM) analysis was used to decompose the movement variability of joints into goal-equivalent variability (GEV) and non-goal-equivalent variability (NGEV). The ratio between GEV and NGEV (UCM(ratio)) quantifies the joint coordination related to postural stability, and a high UCM(ratio) value indicates flexible control of joints. To perform balance tests, participants in this study (healthy young and old adults, 20 each) were asked to stand on a flat platform and on narrow wooden blocks with their eyes open and then eyes closed. RESULTS: In upright balance tests, both old and young adults maintained postural stability. GEV was greater than NGEV across all participants and conditions. However, GEV was higher in the young adults than in the old adults, whereas NGEV was higher in the old adults than in the young adults. Therefore, the old adults exhibited a lower UCM(ratio) than the young adults. CONCLUSION: The old adults were unable to exploit motor abundance and used a less flexible multi-joint coordination pattern to achieve stable balance. The UCM(ratio) value reflects the quality of postural control and can be used for assessing joint coordination in balance disorders.

Effect of a cane on sit-to-stand transfer in subjects with hemiparesis.

OBJECTIVE: The aim of this study was to determine the effect of using a cane on movement time, joint moment, weight symmetry, and muscle activation patterns during sit-to-stand (STS) transfer in healthy subjects and subjects who have had a stroke. DESIGN: Nine subjects with hemiparesis (mean [SD] age, 61.11 [12.83] yrs) and nine healthy adults (mean [SD] age, 63.11 [10.54] yrs) were included. The subjects with hemiparesis performed STS transfer in two randomly assigned conditions: (1) without a cane and (2) with a cane. The healthy subjects performed only STS transfer without a cane. A three-dimensional motion system, force plates, and eletromyography were used to examine STS transfer. The symmetry index between the two limbs was calculated. RESULTS: The movement time of the subjects with hemiparesis in both conditions without a cane and with a cane was longer than that of the healthy subjects without a cane (P < 0.025). However, STS transfer with a cane in the subjects with hemiparesis resulted in shorter movement time, greater knee extensor moment of the paretic limb, and more symmetry of weight bearing than in those without a cane (P < 0.05). The sequence of muscle onset tended to improve with a cane in the subjects with hemiparesis. CONCLUSIONS: Cane use may promote more symmetrical STS transfers rather than compensation by the unaffected limb.

Comparative and reliability studies of neuromechanical leg muscle performances of volleyball athletes in different divisions.

This study compared neural profiles of the leg muscles of volleyball athletes playing in different divisions of Taiwan's national league to analyse the reliability and correlations between their profiles and biomechanical performances. Twenty-nine athletes including 12 and 17 from the first and second divisions of the league, respectively, were recruited. The outcome measures were compared between the divisions, including soleus H-reflex, first volitional (V) wave, normalised rate of electromyography (EMG) rise (RER) in the triceps surae muscles, and RER ratio for the tibialis anterior and soleus muscles, normalised root mean square (RMS) EMG in the triceps surae muscles, antagonist co-activation of the tibialis anterior muscle, rate of force development (RFD), and maximal plantar flexion torque and jump height. Compared to the results of the second division, the neural profiles of the first division showed greater normalised V waves, normalised RER in the lateral gastrocnemius, and normalised RMS EMG of the soleus and lateral gastrocnemius muscles with less antagonist co-activation of the tibialis anterior. First division volleyball athletes showed greater maximal torque, jump height, absolute RFD at 0-30, 0-100, and 0-200 ms, and less in the normalised RFD at 0-200 ms of plantar flexion when compared to the results of those in the second division. Neural profiles correlated to fast or maximal muscle strength or jump height. There are differences in the descending neural drive and activation strategies in leg muscles during contractions between volleyball athletes competing at different levels. These measures are reliable and correlate to biomechanical performances.

H-reflex, muscle voluntary activation level, and fatigue index of flexor carpi radialis in individuals with incomplete cervical cord injury.

BACKGROUND: Individuals with incomplete spinal cord injury (SCI) are predisposed to muscle fatigue during voluntary exercise. However, the origin of fatigue is unclear. OBJECTIVE: The authors examined the motoneuron excitability, muscle activation level, and fatigue properties of the flexor carpi radialis muscle, just below the level of injury. METHODS: Nine individuals with chronic, incomplete cervical cord injury and 9 age-matched healthy individuals were recruited. The authors tested maximum voluntary contraction (MVC), motoneuron excitability by the maximum amplitude of the H-reflex (Hmax at C-7), and muscle voluntary activation level measured by the interpolated twitch technique. Subjects were fatigued by repetitive maximal voluntary isometric wrist flexion. General fatigue index (GFI), central fatigue index (CFI), and peripheral fatigue index (PFI) of flexor carpi radialis were examined before, during, and immediately after exercise. RESULTS: The Hmax in the SCI group was significantly higher (P = .0028) than in controls. The MVC (P < .001) and voluntary activation level (P = .016) in the SCI group were significantly lower. The GFI and CFI decreased in both the SCI and the non-SCI groups. The PFI in the SCI group was significantly higher (ie, less fatigue) than that in controls at 30 repetitive contractions. CONCLUSIONS: In individuals with incomplete SCI, the deficit in central drive is an important source of muscle weakness and fatigue in the muscle below the level of injury.

Postnatal development of microcyst in the anteroventral cochlear nucleus of the Mongolian gerbil: a light- and electron microscopic study.

We investigated the postnatal formation and origin of the microcyst, which are not fully elucidated at present, in the cochlear nucleus of gerbils. Sixty-six Mongolian gerbils were investigated at the light microscope level, and 35 of them were observed at the electron microscopic level. Foamy structures were evidently found at 2 days of age and remained unchanged through 4-8 days. The first small vacuole, presumably the former microcyst, appeared at 8 days. Myelin sheath bundles first appeared at 13 days. Electron-dense bodies were frequently found in the junction of the superficial layer and the deep layer at 2 days. The medium-sized vacuole was found in close association with the spherical bushy cells in the anteroventral cochlear nucleus (AVCN) as early as 5 weeks. Various large and small vacuoles were presumably coalesced to form a large vacuole at 3 and 6 months. Membranous structures and red blood cells were in the budding-like vacuoles at 6 months. In addition to membranous structures, the microcyst contained distorted mitochondria and parts of myelin sheaths. The vacuole was interposed between spherical bushy cells at age of 10 months. Small vacuoles were mainly located in the flame-shaped neurons at 14 months. An internal detachment and an external protrusion of the myelin sheath into the adjacent microcyst were found. Thus, this study suggests the first appearance of microcysts at 8 days. Also, the microcyst and the blood vessel may exchange their contents through a leakage in the anteroventral cochlear nucleus.

Evoked spinal reflexes and force development in elite athletes with middle-portion Achilles tendinopathy.

STUDY DESIGN: Controlled laboratory study. OBJECTIVES: To compare the neuromuscular function of the triceps surae muscle bilaterally in elite athletes with unilateral chronic Achilles tendinopathy. BACKGROUND: Previous studies suggest that tendinopathies or chronic pain may lead to a spinal/supraspinal level modulation of the excitability or voluntary activation of ipsilateral motor units. However, this has not been studied in Achilles tendinopathy. METHODS: Fourteen college athletes (mean ± SD age, 24.2 ± 1.7 years) who had unilateral chronic middle-portion tendinopathy in their Achilles tendons were recruited. Bilateral measurements of soleus reflex tests, including H-reflex and V wave, and rate of force development (RFD), as well as corresponding electromyography of the tibialis anterior and triceps surae muscles, were performed. Statistical within-subject and between-leg comparisons were made. RESULTS: In the leg with tendinopathy, the V wave of the soleus muscle was significantly increased (P<.001). The side with tendinopathy also had a reduced normalized RFD (0-30, 0-50, and 0-100 ms) in plantar flexion, and concomitant higher electromyography ratios between the tibialis anterior and soleus (0-30 and 0-50 milliseconds) during the early stage of explosive contractions (P<.05). No significant differences were found for H-reflex, maximal plantar flexion and dorsiflexion torque, and absolute RFD. CONCLUSIONS: Higher volitional supraspinal reflexes and lower maximal-strength independent force development occur in the triceps surae of elite athletes with unilateral middle-portion Achilles tendinopathy. These changes potentially indicate an acquired compensatory mechanism for maximal force production and deficits in explosive strength. The RFD is also suggested as a sensitive parameter to depict neuromuscular changes during treatment of chronic tendinopathies.

Effects of virtual reality-augmented balance training on sensory organization and attentional demand for postural control in people with Parkinson disease: a randomized controlled trial.

BACKGROUND: There is a lack of studies related to virtual reality (VR)-augmented balance training on postural control in people with Parkinson disease (PD). OBJECTIVE: The purposes of this study were: (1) to examine the effects of VR-augmented balance training on the sensory integration of postural control under varying attentional demands and (2) to compare the results with those of a conventional balance training (CB) group and an untrained control group. DESIGN: A longitudinal, randomized controlled trial was used. SETTING: The intervention was conducted in the clinic, and the assessment was performed in a research laboratory. PATIENTS: Forty-two people with PD (Hoehn and Yahr stages II-III) were recruited. INTERVENTION: The VR and CB groups received a 6-week balance training program. MEASUREMENTS: The sensory organization tests (SOTs) of computerized posturography with single- and dual-task conditions were conducted prior to training, after training, and at follow-up. Equilibrium scores, sensory ratios, and verbal reaction times (VRTs) were recorded. RESULTS: There were no significant differences in equilibrium scores or VRTs between the VR and CB groups. However, the equilibrium scores in SOT-6 (ie, unreliable vision and somatosensation) of the VR group increased significantly more than that of the control group after training. The equilibrium scores in SOT-5 (ie, unreliable somatosensation with eyes closed) of the CB group also increased significantly more than that of the control group after training. LIMITATIONS: The functional significance of the improvements in equilibrium scores in the SOTs was not known, and the sample size was small. CONCLUSIONS: Both VR and CB training improved sensory integration for postural control in people with PD, especially when they were deprived of sensory redundancy. However, the attentional demand for postural control was not changed after either VR or CB training.

Immediate effects of therapeutic music on loaded sit-to-stand movement in children with spastic diplegia.

The effects of patterned sensory enhancement (PSE) music on muscle power and movement control in children with spastic diplegia (SD) during loaded sit-to-stand (LSTS) were investigated. Twenty-three children with SD aged 5 to 12 years were recruited. Individualized PSE was composed by a music therapist based on each subject's sit-to-stand (STS) movement with 50% 1-repetition maximum load. Each subject performed LSTS continuously for eight repetitions under randomly assigned music or no-music (Control) conditions while the kinematic and kinetic data were measured simultaneously. For the music condition, PSE music was played only during the first five repetitions (PSE condition), and the following three repetitions were referred to as the Continuation condition. Paired t- or Wilcoxon signed rank tests were used to compare the variables between the PSE and Control conditions, and between the Continuation and Control conditions. Compared to the Control condition, greater peak knee extensor power (P=0.009), greater total extensor power (P=0.015), and better center-of-mass smoothness (P=0.01), but less movement time (P=0.003) were found in the PSE condition. Significant effects of the PSE music on the above variables were also found for Continuation condition. The current results showed that individualized PSE music helped improve the performance of LSTS in children with SD. The associated biomechanical features also continued to exist in subsequent movement cycles after the music had ceased. These findings suggest that therapy using LSTS combined with PSE music may be beneficial for rehabilitating children with SD.

Role of the premotor cortex in leg selection and anticipatory postural adjustments associated with a rapid stepping task in patients with stroke.

The premotor cortex (PMC) plays an important role in selecting and preparing for movement. This study investigates how stroke-induced PMC lesions affect stepping leg selection and anticipatory postural adjustments (APAs) preparation. Fifteen hemi-paretic patients (eight with PMC lesions (PMC(Lesion)) and seven PMC spared (PMC(Spared))) and eight age- and sex-matched healthy adults participated in the study. The subjects performed rapid forward stepping with the right or left leg under simple and choice reaction time conditions. The percentage of trials in which the subject showed the correct initial vertical ground reaction force pattern before lift-off of the stepping leg indicated the accuracy in selecting the designated stepping leg. The latency of bilateral contractions in the tibialis anterior (TA) and the reaction time (RT) of the stepping leg represented the time needed to prepare for stepping-related APAs and stepping movement, respectively. All three groups demonstrated a similar rate of accuracy of the stepping leg selection under both conditions. However, in both conditions, the PMC(Lesion) group exhibited a longer RT and TA contraction latency of the affected leg than the healthy and PMC(Spared) groups. The PMC(Lesion) group also presented a longer TA contraction latency of the unaffected leg than the healthy group in both conditions. These results suggest that the PMC is involved in APAs associated with leg stepping movement and that a PMC lesion in one hemisphere impairs APAs of both the contralateral and ipsilateral legs during stepping.

Effects of weight resistance on the temporal parameters and electromyography of sit-to-stand movements in children with and without cerebral palsy.

OBJECTIVE: The purpose of this study was to examine the differences in phase durations and electromyography between children with and without cerebral palsy during sit-to-stand movements with weight resistance. DESIGN: Fifteen children with cerebral palsy and 15 age-matched children with typical development were recruited. They performed sit-to-stand movements while wearing a vest with four different loads (none, low, moderate, and high). Three phases during sit-to-stand and electromyography of vastus lateralis, gluteus maximus, and medial hamstring were recorded. RESULTS: The ascending phase and peak electromyography of vastus lateralis showed a significant interaction between groups and resistance conditions. The children with cerebral palsy took a longer time to stand up than the control group when the load was high (P = 0.004). The peak electromyography of vastus lateralis increased with increasing resistance in the control group (P < 0.017) but not in children with cerebral palsy. Children with cerebral palsy had a higher cocontraction ratio of the medial hamstring/vastus lateralis than the control group (P = 0.001) at all resistance levels. CONCLUSIONS: Children with cerebral palsy took a longer time for the task but did not increase agonist contraction as the control group in response to higher loads. Future research is suggested to see whether agonist contraction will be improved with strengthening therapy.

Brain reorganization after bilateral arm training and distributed constraint-induced therapy in stroke patients: a preliminary functional magnetic resonance imaging study.

BACKGROUND: Bilateral arm training (BAT) and constraint-induced therapy (CIT) have shown beneficial effects in improving motor control and function of the upper extremities (UE) for patients with stroke. Thus far, no study has directly investigated the relative effects of BAT versus CIT on brain reorganization. This study compared the effects of BAT with distributed CIT (dCIT) on brain reorganization and motor function in 6 stroke patients. METHODS: In a pre-post randomized controlled trial, 6 stroke patients received BAT (intensive bilateral simultaneous and symmetrical training) or dCIT (restraint of the unaffected UE combined with intensive training of the affected UE) for a period of 3 weeks, 5 days per week. Functional magnetic resonance imaging (fMRI) examination and 3 clinical measures (Fugl-Meyer Assessment, Action Research Arm Test, and Motor Activity Log) were administered before and after the intervention. RESULTS: After intervention, patients showed varied patterns of fMRI changes and improved motor function. Two well-recovered patients, one from each group, showed large increases in bilateral hemisphere activation, especially in the ipsilesional hemisphere during affected hand movement and in the contralesional hemisphere during unaffected hand movement. During bilateral elbow movement, 3 of the 4 BAT patients showed increased bilateral cerebellum activation, especially in the left cerebellum, whereas 2 dCIT patients showed decreased cerebellar activation. CONCLUSIONS: The findings of this preliminary research revealed that neuroplastic changes after stroke motor rehabilitation may be specific to the intervention. Further research using a larger sample and more complex fMRI tasks is warranted to validate the findings.