Sit-to-Stand Trainer: An Apparatus for Training "Normal-Like" Sit to Stand Movement

Brain (EEG) and muscle (EMG) activity related to 3D sit-to-stand kinematics in healthy adults and in central neurological pathology - A systematic review

BACKGROUND

The sit-to-stand transfer is a fundamental functional movement during normal activities of daily living. Central nervous system disorders can negatively impact the execution of sit-to-stand transfers, often impeding successful completion. Despite its importance, the neurophysiological basis at muscle (electromyography (EMG)) and brain (electroencephalography (EEG)) level as related to the kinematic movement is not well understood.

OBJECTIVES

This review synthesises the published literature addressing central and peripheral neural activity during 3D kinematic capture of sit-to-stand transfers.

METHODS

A pre-registered systematic review was conducted. Electronic databases (PubMed, CINAHL Plus, Web of Science, Scopus and EMBASE) were searched from inception using search operators that included sit-to-stand, kinematics and EMG and/or EEG. The search was not limited by study type but was limited to populations comprising of healthy individuals or individuals with a central neurological pathology.

RESULTS

From a total of 28,770 identified papers, 59 were eligible for inclusion. Ten of these 59 studies received a moderate quality rating; with the remainder rated as weak using the Effective Public Health Practice Project tool. Fifty-eight studies captured kinematic data of sit-to-stand with associated EMG activity only and one study captured kinematics with co-registered EMG and EEG data. Fifty-six studies examined sit-to-stand transfer in healthy individuals, reporting four dynamic movement phases and three muscle synergies commonly used by most individuals to stand-up. Pre-movement EEG activity was reported in one study with an absence of data during execution. Eight studies examined participants following stroke and two examined participants with Parkinson's disease, both reporting no statistically significant differences between their kinematics and muscle activity and those of healthy controls.

SIGNIFICANCE

Little is known about the neural basis of the sit-to-stand transfer at brain level with limited focus in central neurological pathology. This poses a barrier to targeted mechanistic-based rehabilitation of the sit-to-stand movement in neurological populations.

Readiness potential reflects the intention of sit-to-stand movement

The negative-going movement-related cortical potentials are associated with the preparation and execution of the voluntary movements. Thus far, the readiness potential (RP) for simple movements involving either the upper or lower body segments has been studied. We investigated the ability to decode the sit-to-stand movement's intention from the RP, which uses the upper and lower body segments. Therefore, we performed scalp electroencephalography in healthy volunteers. A gyro sensor was placed on the back to detect the movement of the upper body segment, and an electromyogram electrode was placed on the surface of the hamstrings and quadriceps to detect movement of the lower body segment. Our study revealed that a negative RP was evoked around 2 to 3 s before the onset of the upper body movement in the sit-to-stand movement in response to the start cue. The RP had a negative peak and a steeper negative slope from - 0.8 to - 0.001 s just before the onset of the upper body movement. Negative-going RPs reflect the intention of preparation/execution of the sit-to-stand movement. Therefore, we used the morphological component analysis method to extract the morphology of RPs from a single trial. This morphology of RPs is a promising aspect for limb neurotrophies or neurorehabilitation devices.

Combined Therapy With Functional Electrical Stimulation and Standing Frame in Stroke Patients

OBJECTIVE

To investigate the effects of combination functional electrical stimulation (FES) and standing frame training on standing balance in stroke patients.

METHODS

Patients who had hemiparesis and postural instability after stroke were randomly assigned to one of the two groups; study group underwent FES on the quadriceps and tibialis anterior muscle simultaneously with standing balance training. The control group received standing frame training and FES separately. Both the groups received their respective therapies for 3 weeks. Stability index in Biodex Balance master system, Berg Balance Scale (BBS), manual muscle test, the Korean version of Modified Barthel Index, and Korean version of Mini-Mental State Examination were used to evaluate the effects of the treatment.

RESULTS

In total, 30 patients were recruited to the study group and 30 to the control group. Three weeks after treatment, both the groups showed improvement in postural stability scores and physical and cognitive functions. When changes in postural stability were compared between the groups, the study group showed more significant improvement than the control group with regards to the scores of BBS and the stability indices.

CONCLUSION

In this study, we found the therapeutic effectiveness of combined therapy of FES and standing frame in subacute stroke patients. The presented protocol is proposed as time-saving and can be applied easily in the clinical setting. Thus, the proposed combined therapy could be a useful method for improving standing balance in subacute stroke patients.

Nondestructive Estimation of Muscle Contributions to STS Training with Different Loadings Based on Wearable Sensor System

Partial body weight support or loading sit-to-stand (STS) rehabilitation can be useful for persons with lower limb dysfunction to achieve movement again based on the internal residual muscle force and external assistance. To explicate how the muscles contribute to the kinetics and kinematics of STS performance by non-invasive in vitro detection and to nondestructively estimate the muscle contributions to STS training with different loadings, a wearable sensor system was developed with ground reaction force (GRF) platforms, motion capture inertial sensors and electromyography (EMG) sensors. To estimate the internal moments of hip, knee and ankle joints and quantify the contributions of individual muscle and gravity to STS movement, the inverse dynamics analysis on a simplified STS biomechanical model with external loading is proposed. The functional roles of the lower limb individual muscles (rectus femoris (RF), gluteus maximus (GM), vastus lateralis (VL), tibialis anterior (TA) and gastrocnemius (GAST)) during STS motion and the mechanism of the muscles' synergies to perform STS-specific subtasks were analyzed. The muscle contributions to the biomechanical STS subtasks of vertical propulsion, anteroposterior (AP) braking and propulsion for body balance in the sagittal plane were quantified by experimental studies with EMG, kinematic and kinetic data.

Comparison of the tibialis anterior and soleus muscles isolation ratios during the sit-to-stand movement in elderly people

[Purpose] To compared activation of the tibialis anterior and soleus muscles during the sit-to-stand movement in elderly people. [Subjects and Methods] Ten elderly women were enrolled. The activities of the dominant lower extremity muscles were measured using a wireless electromyography system. Subjects performed natural sit-to-stand tasks. [Results] In the pre-thigh off phase, the tibialis anterior isolation ratio was significantly higher than the soleus isolation ratio. In the post-thigh off phase, the tibialis and soleus isolation ratios did not significantly differ. [Conclusion] This result suggests that selective soleus exercises might help to reduce the risk of falling in the elderly.