Passive Movement Research Articles

We like to move it, move it: A perspective on performing passive leg movement as a non-invasive assessment of vascular function in pediatric populations.

The passive leg movement (PLM) technique is a non-invasive assessment of lower-limb vascular function. PLM is methodologically simple to perform and utilizes Doppler ultrasound to determine leg blood flow (LBF) through the common femoral artery at rest and in response to passive movement of the lower leg. LBF responses to PLM have been reported to be mostly nitric oxide (NO)-mediated when performed in young adults. Moreover, PLM-induced LBF responses, as well as the NO contribution to PLM-induced LBF responses, are reduced with age and in various diseased populations, demonstrating the clinical utility of this non-invasive test. However, no PLM studies to date have included children or adolescents. Since its conception in 2015, our laboratory has performed PLM on hundreds of individuals including a large cohort of children and adolescents. Thus, the purpose of this perspective article is threefold: 1) to uniquely discuss the feasibility of performing PLM in children and adolescents, 2) to report PLM-induced LBF values from our laboratory in 7-17-year-olds, and 3) to discuss considerations for making comparisons among pediatric populations. Based on our experiences performing PLM in children and adolescents (among various other age groups), it is our perspective that PLM can feasibly be performed in this population. Further, data from our laboratory may be used to provide context for typical PLM-induced LBF values that could be observed in children and adolescents, as well as across the lifespan.

Methodical Approach to fMRI Assessment of Motor Connectome in Patients After Severe Traumatic Brain Injury

The aim of the study. To identify alterations of motor connectome in patients with varying degrees of hemi-paresis after severe traumatic brain injury (TBI) versus healthy volunteers.Material and methods. The study included 29 patients with TBI aged 18 to 35 years and 23 healthy volunteers aged 20 to 32 years. Participants underwent a comprehensive clinical and neuroimaging study. Motor impairment was evaluated via muscle strength assessment using a five-score scale. The fMRI data were processed using a dedicated CONN software package. Anatomical 3-D connection masks of the whole brain motor functional system in the predetermined regions of interest (ROIs) were used for the assessment. Then the group indicators of functional connectivity (statistical significance of the connection) were computed.Results. It was established that the structure of connections in healthy individuals performing active movement with the right (leading) hand is determined by formation of focus in the cortical and subcortical ROIs in the contralateral hemisphere. With passive movement of the right hand the pale ball becomes functionally active in addition to the activated areas. The striopallidar system structures became active on both sides, and connectivity with the additional motor cortex and the motor cortex of the ipsilateral hemisphere emerged as the paresis increased during active movement. The focus of motor activity during passive movement was determined in the motor cortex and putamen, which makes it possible to use a passive test in patients with gross motor disorders or unconsciousness for a full assessment of the entire structural and functional brain connectome.Conclusion. As hemiparesis increased in patients after severe traumatic brain injury, a decrease in the total number of connection appeared; simultaneous engagement of ancient primordial structures, such as bilateral activation of pale globes, demonstrated neuroplasticity.

Prototype of a Continuous Passive Motion device for shoulder rehabilitation

Continuous Passive Motion - CPM - is a therapeutic method that provides fast and safe patient rehabilitation. Considering the fact that the equipment performs the movement along with the patient, who also does it but passively, this treatment procedure can immediately be applied in the postoperative care period. Although this technique makes recovery faster, as strains will be spared from ligaments, muscles and tendons, not all clinics can offer CPM therapy due to its high cost. Bearing in mind the existence of such equipment that performs the aforementioned motion, the objective of this work was the development and manufacture of a prototype device for continuous passive shoulder movement, with costs reduced to an approximate value of USD$730.00 compared to the average price in the market which is around USD$1510.00. This difference in values would make it affordable for a greater majority of clinics and offices to purchase them and, thus, promote the accelerated timely recovery of the limb after operation, for a larger number of patients, allowing these patients to return to their daily tasks in shorter period of time. For the execution of the prototype, specific mechanical manufacturing methods, such us turning, milling and welding of materials, were applied in order to make the equipment safe and effective, provide comfort for the patient and, above all, make the device affordable for most physiotherapy clinics. The material used for the production was stainless steel, cables, pulleys, tilting automation kit and inductive sensors.

IMPROVING THE METHODOLOGY OF PHYSICAL THERAPY IN ATHLETES WITH INJURIES OF THE KNEE JOINT CONNECTIVE APPARATUS

Description and results of the action developed programs of kinesiotherapy with a combination of kinesiotape to restore impaired locomotor functions of the knee joint and the possibility of continuation playing sports after arthroscopic operations for damage to the ligamentous apparatus.
 Injuries of the musculoskeletal system (MS) are quite common, especially in athletes. According to statistics, up to 50-70% of all ORA injuries occur in the knee joint. Most often, this type of injury is received by athletes, representatives of complex coordination sports and martial arts. Among injuries to the knee joint, injuries to the ligaments, which later cause post-traumatic instability, take second place after damage to the menisci.
 35 patients with injuries of the ligamentous apparatus of the CS (12 women and 23 men) who underwent arthroscopic surgery took part in our study. The patients were active athletes in various sports, in particular game sports. Patients were divided into two groups (the main group and the comparison group) depending on the kind of restorative treatment program. The main group included 23 people whose average age was (24.3±3.0) years. Patients of this group received a rehabilitation program in the conditions of an educational and scientific center Department of Physical Therapy, Occupational Therapy of PNU named after Vasyl Stefanyk. The comparison group (CP) consisted of 12 people, the average age of which was (23.8±3.1) years, who underwent rehabilitation in the polyclinic department of the 1st city polyclinic.
 The individual program of physical therapy for OG patients included kinesiotherapy and massage muscles of the lower limb, physiotherapeutic procedures and the use of kinesiotape. Kinesiotherapy included therapeutic gymnastics of independent classes, massage for the prevention of contracture of the CS and atrophy of the thigh muscles. Various types of massage were used - classic manual massage with passive movements in the joints, self-massage and hydro massage. Physiotherapy procedures were aimed at reducing swelling and pain, preventing the development of the inflammatory process. Patients were prescribed electrophoresis of painkillers, UV irradiation, and UHF or laser therapy, applications of ozokerite or paraffin. These procedures contribute to the stimulation of lymph and blood circulation, trophic processes in the joints, increasing the amplitude of movements and restoring the strength of the muscles of the limb.
 In order to objectify the results of the restorative treatment, the functional ability of the lower limb was assessed using the Lovett muscle test (six-point assessment of muscle strength), the amplitude of movements in the knee joint (goniometry) and the visual analog pain scale (VAS) on the 14th day, 1.5 months, 3 and 5 months after the operation. This part of the study showed the advantages of the developed rehabilitation program using elements of kinesiotaping, as only a few patients with functional disorders were found in OG while in the comparison group their number was up to 20%. Improvement of joint function and normalization of muscle strength and goniometry indicators occurred earlier in OG patients by 2 weeks, compared to patients who underwent restorative treatment according to the traditional method of the city polyclinic.
 A special place in the assessment of results is given to determining the quality of life using the SF-36 questionnaire. The dynamics of quality of life indicators showed a gradual and likely improvement of all components of quality of life at the entire stage of post-hospital rehabilitation. We proved that the proposed rehabilitation program is more effective compared to the traditional methods of restorative treatment of a medical institution and allows achieving better results in restoring the functions of the knee joint in the shortest possible time after the injury and can be recommended for wide use.

Peripersonal encoding of forelimb proprioception in the mouse somatosensory cortex

Conscious perception of limb movements depends on proprioceptive neural responses in the somatosensory cortex. In contrast to tactile sensations, proprioceptive cortical coding is barely studied in the mammalian brain and practically non-existent in rodent research. To understand the cortical representation of this important sensory modality we developed a passive forelimb displacement paradigm in behaving mice and also trained them to perceptually discriminate where their limb is moved in space. We delineated the rodent proprioceptive cortex with wide-field calcium imaging and optogenetic silencing experiments during behavior. Our results reveal that proprioception is represented in both sensory and motor cortical areas. In addition, behavioral measurements and responses of layer 2/3 neurons imaged with two-photon microscopy reveal that passive limb movements are both perceived and encoded in the mouse cortex as a spatial direction vector that interfaces the limb with the body’s peripersonal space.

From one to many: Hypertonia in schizophrenia spectrum psychosis an integrative review and adversarial collaboration report

Different types of resistance to passive movement, i.e. hypertonia, were described in schizophrenia spectrum disorders (SSD) long before the introduction of antipsychotics. While these have been rediscovered in antipsychotic-naïve patients and their non-affected relatives, the existence of intrinsic hypertonia vs drug-induced parkinsonism (DIP) in treated SSD remains controversial. This integrative review seeks to develop a commonly accepted framework to specify the putative clinical phenomena, highlight conflicting issues and discuss ways to challenge each hypothesis and model through adversarial collaboration.The authors agreed on a common framework inspired from systems neuroscience. Specification of DIP, locomotor paratonia (LMP) and psychomotor paratonia (PMP) identified points of disagreement. Some viewed parkinsonian rigidity to be sufficient for diagnosing DIP, while others viewed DIP as a syndrome that should include bradykinesia. Sensitivity of DIP to anticholinergic drugs and the nature of LPM and PMP were the most debated issues.It was agreed that treated SSD should be investigated first. Clinical features of the phenomena at issue could be confirmed by torque, EMG and joint angle measures that could help in challenging the selectivity of DIP to anticholinergics. LMP was modeled as the release of the reticular formation from the control of the supplementary motor area (SMA), which could be challenged by the tonic vibration reflex or acoustic startle. PMP was modeled as the release of primary motor cortex from the control of the SMA and may be informed by subclinical echopraxia. If these challenges are not met, this would put new constraints on the models and have clinical and therapeutic implications.

Enhanced corticospinal excitability in the tibialis anterior during static stretching of the soleus in young healthy individuals.

Corticospinal excitability is known to be affected by afferent inflow arising from the proprioceptors during active or passive muscle movements. Also during static stretching (SS) afferent activity is enhanced, but its effect on corticospinal excitability received limited attention and has only been investigated as a single average value spread over the entire stretching period. Using transcranial magnetic stimulation (TMS) the present study was conducted to explore the time course of corticospinal excitability during 30 seconds SS. Motor evoked potentials (MEPs) after TMS were recorded from soleus (SOL) and tibialis anterior (TA) muscles in 14 participants during: a passive dynamic ankle dorsiflexion (DF), at six different time points during maximal individual SS (3, 6, 9, 18, 21 and 25 seconds into stretching), during a passive dynamic ankle plantar flexion (PF) and following SS. To explore the time course of corticospinal excitability during the static lengthened phase of a muscle stretch, the stretching protocol was repeated several times so that it was possible to collect a sufficient number of stimulations at each specific time point into SS, as well as during DF and PF. During passive DF, MEPs amplitude was greater than baseline in both TA and SOL (p = .001 and p = .005 respectively). During SS, MEPs amplitude was greater than baseline in TA (p = .006), but not in SOL. No differences between the investigated time points were found and no trend was detected throughout the stretching time. No effect in either muscle was observed during passive PF and after SS. These results could suggest that an increased activity of secondary afferents from SOL muscle spindles exert a corticomotor facilitation on TA. The muscle-nonspecific response observed during passive DF could instead be attributed to an increased activation within the sensorimotor cortical areas as a result of the awareness of the foot passive displacements.

Concurrent metaboreflex activation increases chronotropic and ventilatory responses to passive leg movement without sex-related differences

Previous studies in animal models showed that exercise-induced metabolites accumulation may sensitize the mechanoreflex-induced response. The aim of this study was to assess whether the magnitude of the central hemodynamic and ventilatory adjustments evoked by isolated stimulation of the mechanoreceptors in humans are influenced by the prior accumulation of metabolic byproducts in the muscle. 10 males and 10 females performed two exercise bouts consisting of 5-min of intermittent isometric knee-extensions performed 10% above the previously determined critical force. Post-exercise, the subjects recovered for 5 min either with a suprasystolic circulatory occlusion applied to the exercised quadriceps (PECO) or under freely-perfused conditions (CON). Afterwards, 1-min of continuous passive leg movement was performed. Central hemodynamics, pulmonary data, and electromyography from exercising/passively-moved leg were recorded throughout the trial. Root mean square of successive differences (RMSSD, index of vagal tone) was also calculated. Δpeak responses of heart rate (ΔHR) and ventilation (Delta dot{V}_{{text{E}}}) to passive leg movement were higher in PECO compared to CON (ΔHR: 6 ± 5 vs 2 ± 4 bpm, p = 0.01; 3.9 ± 3.4 vs 1.9 ± 1.7 L min−1, p = 0.02). Δpeak of mean arterial pressure (ΔMAP) was significantly different between conditions (5 ± 3 vs − 3 ± 3 mmHg, p < 0.01). Changes in RMSSD with passive leg movement were different between PECO and CON (p < 0.01), with a decrease only in the former (39 ± 18 to 32 ± 15 ms, p = 0.04). No difference was found in all the other measured variables between conditions (p > 0.05). These findings suggest that mechanoreflex-mediated increases in HR and dot{V}_{{text{E}}} are sensitized by metabolites accumulation. These responses were not influenced by biological sex.

POLYETHYLENE LINER MOTION IN DUAL MOBILITY HIP PROSTHESES: STATIC AND DYNAMIC RADIOSTEREOMETRY IN 16 CASES ONE YEAR AFTER OPERATION

Dual mobility hip arthroplasty utilizes a freely rotating polyethylene liner to protect against dislocation. As liner motion has not been confirmed in vivo, we investigated the liner kinematics in vivo using dynamic radiostereometry.16 patients with Anatomical Dual Mobility acetabular components were included. Markers were implanted in the liners using a drill guide. Static RSA recordings and patient reported outcome measures were obtained at post-op and 1-year follow-up. Dynamic RSA recordings were obtained at 1-year follow-up during a passive hip movement: abduction/external rotation, adduction/internal rotation (modified FABER-FADIR), to end-range and at 45° hip flexion. Liner- and neck movements were described as anteversion, inclination and rotation.Liner movement during modified FABER-FADIR was detected in 12 of 16 patients. Median (range) absolute liner movements were: anteversion 10° (5–20), inclination 6° (2–12), and rotation 11° (5–48) relative to the cup. Median absolute changes in the resulting liner/neck angle (small articulation) was 28° (12–46) and liner/cup angle (larger articulation) was 6° (4–21). Static RSA showed changes in median (range) liner anteversion from 7° (-12–23) postoperatively to 10° (-3–16) at 1-year follow-up and inclination from 42 (35–66) postoperatively to 59 (46–80) at 1-year follow-up. Liner/neck contact was associated with high initial liner anteversion (p=0.01).The polyethylene liner moves over time. One year after surgery the liner can move with or without liner/neck contact. The majority of movement is in the smaller articulation between head and liner.

Diagnosing Functional Neurological Disorder through History and Physical Examination: A Case Report

Differentiating between stroke and stroke mimics (i.e., non-vascular conditions) is a major challenge, as they often involve similar presenting symptoms. A common type of stroke mimic is functional neurological disorder (FND), a somatic disorder caused by severe stress, emotional conflict, or a psychiatric disorder usually presenting with one or more neurologic symptoms. This condition is associated with voluntary motor and sensory symptoms that are internally inconsistent with identifiable neurological diseases and lack structural lesions. We describe a 54-year-old female with a history of transient ischemic attack resulting in bilateral blindness and recent social stressors, who presented with right-sided facial and extremity motor and sensory deficits, bilateral diplopia, and dysphagia. Her left upper and lower extremities had 2 out of 5 motor strength, a weak hand squeeze, and a positive Babinski reflex on the contralateral side of her weakness, which resolved the next day. In addition, decreased sensation to light touch and temperature over the right arm and leg were appreciated without a dermatomal pattern. Given the negative stroke work-up, atypical physical exam findings, prior history of blindness, and in the setting of recent psychological stressors, her acute motor and sensory deficits were diagnosed as FND after evaluation by the Neurology service. The current case demonstrates the following important features of making a FND diagnosis: 1) careful history taking in eliciting potential psychological stressors; 2) a comprehensive neurological examination assessing the presence of findings specific for FND (e.g., greater weakness with active rather than passive movements, fluctuating weakness); 3) multidisciplinary collaboration with neurology and psychiatry providers to aid in performing a comprehensive assessment.

Comparison between actigraphy and parental reporting for sleep assessment in hospitalized infants.

Our aim is to compare data obtained through actigraphy with data from parental diaries to evaluate their concordance. We enrolled 55 hospitalized infants aged 1-12 months with a gestational age higher than 35 weeks and without sleep disorders, complications due to perinatal events or movement deficits. They were monitored using both methods for 24 hours. Total diurnal and nocturnal sleep times and the numbers of awakenings were evaluated. Actigraph data were analyzed with Sadeh's algorithm. Sleep time was analyzed in 51 infants. The average sleep time was 724.33 (±104.69) minutes according to the diaries and 625.18 (±109.14) minutes according to the actigraphy data, yielding a difference of 99.16 (±97.53) minutes (P<0.0001). The average number of awakenings was 8.65 (±3.78) according to the diaries and 13.43 (±5.09) according to the actigraphy data, with a difference of -4.78 (±4.50) (P<0.0001). A low concordance (≤0.66) was found between the two methods. The two methods provided different results (P<0.05) regarding nocturnal and diurnal sleep. After accounting for differences in disease and feeding types, the actigraphy and diary data were significantly different except for the number of daily awakenings. Concordances were higher in infants with respiratory diseases and those who were breastfed, except for the evaluation of nocturnal sleep. Concordance between actigraphy and parental reporting is low. Actigraphy may be a useful and easy to use method for collecting data on infants' sleep than a parental diary, but actigraphy data should be analyzed in conjunction with infants' passive movement records.

Assessment of Passive Upper Limb Stiffness and Its Function in Post-Stroke Individuals Wearing an Inertial Sensor during the Pendulum Test

This article proposes the evaluation of the passive movement of the affected elbow during the pendulum test in people with stroke and its correlation with the main clinical scales (Modified Ashworth Scale, Motor Activity Log, and Fulg Meyer). An inertial sensor was attached to the forearm of seven subjects, who then passively flexed and extended the elbow. Joint angles and variables that indicate viscoelastic properties, stiffness (K), damping (B), E1 amp, F1 amp, and relaxation indices were collected. The results show that the FM scale is significantly correlated with the natural frequency (p = 0.024). The MAL amount-of-use score correlates with the natural frequency (p = 0.024). The variables E1 amp, F1 amp, RI, and ERI are not correlated with the clinical scales, but they correlate with each other; the variable E1 amp correlates with F1 amp (p = 0.024) and RI (p = 0.024), while F1 amp correlates with ERI (p = 0.024). There was also a correlation between the natural frequency and K (r = 0.96, p = 0.003). Non-linear results were found for the properties of the elbow joint during the pendulum test, which may be due to the presence of neural and non-neural factors. These results may serve as a reference for future studies if alternative scales do not provide an accurate reflection.

Perception of self-generated and externally-generated visual stimuli: Evidence from EEG and behavior.

Efference copy-based forward model mechanisms may help us to distinguish between self-generated and externally-generated sensory consequences. Previous studies have shown that self-initiation modulates neural and perceptual responses to identical stimulation. For example, event-related potentials (ERPs) elicited by tones that follow a button press are reduced in amplitude relative to ERPs elicited by passively attended tones. However, previous EEG studies investigating visual stimuli in this context are rare, provide inconclusive results, and lack adequate control conditions with passive movements. Furthermore, although self-initiation is known to modulate behavioral responses, it is not known whether differences in the amplitude of ERPs also reflect differences in perception of sensory outcomes. In this study, we presented to participants visual stimuli consisting of gray discs following either active button presses, or passive button presses, in which an electromagnet moved the participant's finger. Two discs presented visually 500-1250 ms apart followed each button press, and participants judged which of the two was more intense. Early components of the primary visual response (N1 and P2) over the occipital electrodes were suppressed in the active condition. Interestingly, suppression in the intensity judgment task was only correlated with suppression of the visual P2 component. These data support the notion of efference copy-based forward model predictions in the visual sensory modality, but especially later processes (P2) seem to be perceptually relevant. Taken together, the results challenge the assumption that N1 differences reflect perceptual suppression and emphasize the relevance of the P2 ERP component.

Pharmacological modulation of adrenergic tone alters the vasodilatory response to passive leg movement in young but not in old adults.

The age-related increase in α-adrenergic tone may contribute to decreased leg vascular conductance (LVC) both at rest and during exercise in the old. However, the effect on passive leg movement (PLM)-induced LVC, a measure of vascular function, which is markedly attenuated in this population, is unknown. Thus, in eight young (25 ± 5 yr) and seven old (65 ± 7 yr) subjects, this investigation examined the impact of systemic β-adrenergic blockade (propanalol, PROP) alone, and PROP combined with either α1-adrenergic stimulation (phenylephrine, PE) or α-adrenergic inhibition (phentolamine, PHEN), on PLM-induced vasodilation. LVC, calculated from femoral artery blood flow and pressure, was determined and PLM-induced Δ peak (LVCΔpeak) and total vasodilation (LVCAUC, area under curve) were documented. PROP decreased LVCΔpeak (PROP: 4.8 ± 1.8, Saline: 7.7 ± 2.7 mL·mmHg-1, P < 0.001) and LVCAUC (PROP: 1.1 ± 0.7, Saline: 2.4 ± 1.6 mL·mmHg-1, P = 0.002) in the young, but not in the old (LVCΔpeak, P = 0.931; LVCAUC, P = 0.999). PE reduced baseline LVC (PE: 1.6 ± 0.4, PROP: 2.3 ± 0.4 mL·min-1·mmHg-1, P < 0.01), LVCΔpeak (PE: 3.2 ± 1.3, PROP: 4.8 ± 1.8 mL·min-1·mmHg-1, P = 0.004), and LVCAUC (PE: 0.5 ± 0.4, PROP: 1.1 ± 0.7 mL·mmHg-1, P = 0.011) in the young, but not in the old (baseline LVC, P = 0.199; LVCΔpeak, P = 0.904; LVCAUC, P = 0.823). PHEN increased LVC at rest and throughout PLM in both groups (drug effect: P < 0.05), however LVCΔpeak was only improved in the young (PHEN: 6.4 ± 3.1, PROP: 4.4 ± 1.5 mL·min-1·mmHg-1, P = 0.004), and not in the old (P = 0.904). Furthermore, the magnitude of α-adrenergic modulation (PHEN - PE) of LVCΔpeak was greater in the young compared with the old (Young: 3.35 ± 2.32, Old: 0.40 ± 1.59 mL·min-1·mmHg-1, P = 0.019). Therefore, elevated α-adrenergic tone does not appear to contribute to the attenuated vascular function with age identified by PLM.NEW & NOTEWORTHY Stimulation of α1-adrenergic receptors eliminated age-related differences in passive leg movement (PLM) by decreasing PLM-induced vasodilation in the young. Systemic β-blockade attenuated the central hemodynamic component of the PLM response in young individuals. Inhibition of α-adrenergic receptors did not improve the PLM response in older individuals, though withdrawal of α-adrenergic modulation augmented baseline and maximal vasodilation in both groups. Accordingly, α-adrenergic signaling plays a role in modulating the PLM vasodilatory response in young but not in old adults, and elevated α-adrenergic tone does not appear to contribute to the attenuated vascular function with age identified by PLM.

Lattice Structure and Spatial Network Models Incorporating into Simulating Human-Mediated Dispersal of the Western Conifer Seed Bug Populations in South Korea

The western conifer seed bug (WCSB), Leptoglossus occidentalis, has expanded rapidly in the southern peninsula of Korea since it was first reported in southeastern Korea in 2010. Two types of human-mediated passive movements were devised for modeling the rapid advancement of the pest population in this study: traffic effects and forest-product transportation. A lattice structure model (LSM) was developed to accommodate the traffic effects pertaining to the local area along with the natural population dynamics of the pest. Separately, a spatial network model (SNM) was constructed to present the passive movement of the WCSB because of forest-product transportation between all local areas in Korea. The gravity rule was applied to obtain the parameters for forest-product transportation between the local areas. LSM and SNM were linked to the two present types of passive movements in the model. The model simulated fast, linear advancement in a short period, compared with slow, circular advancement because of the conventional natural diffusion process of populations. Simulation results were comparable to field data observed in the southern peninsula of Korea, matching the rapid advancement of about 400 km to the north area (Seoul) from the south area (Changwon) within six years and expanding across the nation in 10 years. Possible saturation of populations was predicted in the 2020s if survival conditions for the WCSB were favorable and no control efforts were given in field conditions. Dispersal because of SNM notably surpassed the dispersal simulated by LSM when the WCSB population rapidly dispersed over a wide area. The Allee-effect and contribution ratio of SNM were the factors governing the rapid expansion of pest populations. The possibility of using the combined model was further discussed to address different types of human-mediated passive movements associated with population dynamics in forest pest dispersal.

Dynamic Ultrasound Examination for Extensor Pollicis Longus Tendon Rupture after Palpation-Guided Corticosteroid Injection.

This report aimed to present a case of wrist-tendon rupture and to discuss a rare complication after corticosteroid injection. A 67-year-old woman had difficulty extending her left-thumb interphalangeal joint several weeks after a palpation-guided local corticosteroid injection. Passive motions remained intact without sensory abnormalities. Ultrasound examination showed hyperechoic tissues at the site of the extensor pollicis longus (EPL) tendon at the wrist level and an atrophic EPL muscle stump at the forearm level. Dynamic imaging demonstrated no motion in the EPL muscle during passive thumb flexion/extension. The diagnosis of complete EPL rupture, possibly due to inadvertent intratendinous corticosteroid injection, was therefore confirmed.

Probing motor dynamics at the muscle level-Acoustic myography in Parkinson's disease.

Acoustic myography (AMG) noninvasively probes muscle activity. We explored whether AMG captures abnormal motor activity in patients with Parkinson's disease (PD) and how this activity is modulated by antiparkinsonian medication. Twenty patients with PD underwent AMG of the biceps, triceps, extensor carpi radialis longus, and adductor policis muscles of the more affected arm during active and passive movements, using a mobile AMG device (CURO, Denmark). AMG and assessment of motor symptoms were performed in a pragmatic off-medication state, as well as one and 3 h after oral intake of 200 mg levodopa. Three AMG parameters were calculated using the CURO analysis system. Motor efficiency was expressed by the E-score, muscle fiber recruitment by the temporal T-score, spatial summation by the S-score, and S/T ratio. Twenty age- and sex-matched healthy subjects served as controls. Group mean values were statistically compared using unpaired two-tailed adjusted t-test and ANOVA with Tukey´s correction for multiple comparison (p≤ 0.05). For the biceps and extensor carpi radialis longus muscles, the active movement S:T ratio was lower in PD relative to healthy controls. The E-score was also lower during active and passive flexion/extension movements in the off-medication state. No significant between-group differences in the AMG scores were noted for the triceps muscle during active or passive movements. The active S:T ratio and the E-score during active elbow flexion and extension may offer a useful means to quickly assess abnormal motor activity and the effect of drug treatment in PD.

Impedance characteristic of the human arm during passive movements

This paper describes the impedance characteristics of the human arm during passive movement. The arm was moved in the desired trajectory. The motion was actuated by a 1-degree-of-freedom robot system. Trajectories used in the experiment were minimum jerk (the rate of change of acceleration) trajectories, which were found during a human and human cooperative task and optimum for muscle movement. As the muscle is mechanically analogous to a spring-damper system, a second-order equation was considered as the model for arm dynamics. In the model, inertia, stiffness, and damping factor were considered. The impedance parameters were estimated from the position and torque data obtained from the experiment and based on the “Estimation of Parametric Model”. It was found that the inertia is almost constant over the operational time. The damping factor and stiffness were high at the starting position and became near zero after 0.4 seconds.

Fracture of The Sustentaculum Tali: Features and Surgical Management for Fracture Reduction

Sustentaculum tali is a horizontal shelf-like projection on the medial part of the calcaneum. The medial facet articulates to the talus and supports the medial column of the foot. The spring ligament originates at the plantar aspect of sustentaculum tali, and flexor hallucis longus passes below it and indirectly supports the longitudinal arch of the foot. Sustentaculum tali is a strong cortical bone, so its isolated fracture is unusual. Therefore, the fracture of the sustentaculum tali is easily misdiagnosed. The patients complain of pain below the medial malleolus and also on passive movement of the flexor hallucis longus tendon. The patient has a history of falls from height with the foot supinated or associated talus fracture. Sustentaculum tali fractures are sometimes considered to be extra-articular fractures. CT scan helps diagnose the intraarticular medial facet involvement in this fracture and is now regarded as intra-articular. Need of the study is to make the clinicians aware that these fractures, even if rare, do happen, if mismanaged, may lead to complications like impingement of flexor hallucis longus, post-traumatic arthritis etc. The study aimed to identify the clinical features and diagnosis of sustentaculum tali fracture and its management to prevent complications. Surgical reconstruction of the sustentaculum tali with a direct medial approach and fixation with cannulated cancellous screws. Ten patients were operated on in the last five years, and seven patients showed up for follow-up and had excellent results per the AOFAS scoring system. All of the fractures had signs of radiological union by the end of the third month. In Conclusion, Sustentaculum tali fracture, when suspected, should not be ignored, and the fracture must be fixed surgically. The current aspect of surgical fixation is befitting and should not be disregarded.

A 2-Degree-of-Freedom Quasi-Passive Prosthetic Wrist With Two Levels of Compliance

Restoring the function of a missing hand is still a grand challenge for bioengineers. We witnessed significant recent advances in the development of myoelectric hand prostheses and their controllers. Conversely, the wrist joint is generally overlooked in prosthetics, despite playing a fundamental role in orienting the hand in space. Indeed, it may account for several degrees of freedom of the hand in reducing compensatory movements. We acknowledge that an active, three-degree-of-freedom prosthetic wrist is not a viable option for a self-contained prosthesis, therefore we merged in one design two opposed passive behaviors. The proposed wrist can automatically transition between a compliant mode, which exhibits relatively low stiffness allowing for passive motions around two rotational axes (wrist flexion/extension and radial/ulnar deviation), and a stiff mode, which grants stability during manipulation. To switch mode, no additional control input - hence cognitive burden - from the user is needed: it occurs synchronously with the prosthetic hand opening and closing motion, such that the wrist is compliant during reaching and stiff during manipulation. Our device proved reliable on the test bench and useful in a pilot test with an amputee volunteer, motivating further developments and more extensive testing to prove its effectiveness.