Effect of Anterior Ankle-Foot Orthoses on Weight Shift in Persons With Stroke

The effect of strabismus surgery on the dynamic balance in children with strabismus

Purpose: To evaluate the effect of strabismus surgery on dynamic balance by using computerized dynamic posturography in children with strabismus. Methods: This study was designed as a prospective observational study. Hearing tests and complete ophthalmological examinations were performed for all subjects. Patients with moderate and severe amblyopia, hearing loss at any level, and/or any suspicion of balance impairment were excluded from the study. Postural stability evaluation was performed by computerized dynamic posturography including sensory organization test, adaptation test, and rhythmic weight shift test. All tests were applied preoperatively and in the postoperative 1st and 3rd months, respectively. Results: Fifteen female and twelve male pre-adolescents aged between 7 and 12 (9.67 ± 1.62 years) were included in the current study. In the sensory organization test, the preoperative visual ratio percentages (73.19 ± 14.95%) improved statistically significantly at the postoperative 1st and 3rd months (78.59 ± 16.21% and 81.44 ± 14.18; p = .026, p = .021, respectively). The preoperative toes up (110.66 ± 33,48) and toes down (81.46 ± 28.36) adaptation tests improved statistically significantly in the postoperative 3rd month (88.74 ± 20.94 and 63.36 ± 16.03; p < .001, p = .001, respectively). In the Rhythmic Weight Shift test, the postoperative 3rd-month directional control (forward-backward) value (74.25 ± 11.51%) was statistically significantly higher compared to the preoperative directional control (forward-backward) value (67.76 ± 11.38%) (p = .011). The postoperative 3rd-month directional control (forward-backward) value (74.25 ± 11.51%) was statistically significantly higher compared to the postoperative 1st-month directional control (forward-backward) value (68.43 ± 14.00%) (p = .028). Conclusion: Surgical treatment resulted in an improvement in the maintenance of dynamic balance in children with strabismus.

Effectiveness of cerebellar vermis intermittent theta-burst stimulation in improving trunk control and balance function for patients with subacute stroke: a randomised controlled trial protocol

INTRODUCTION

Balance impairments frequently occur after stroke. Achieving effective core trunk stability is the key to improving balance ability. However, there is still a lack of advanced well-defined rehabilitation protocols for balance improvement in patients with stroke. Intermittent theta-burst stimulation (iTBS) is a non-invasive brain activity modulation strategy that can produce long-term potentiation. The cerebellar vermis is a fundamental structure involved in balance and motor control. However, no study has demonstrated the therapeutic effect and potential mechanism of cerebellar vermis iTBS on balance after stroke.

METHODS AND ANALYSIS

This study will be a prospective single-centre double-blind randomised controlled clinical trial with a 3-week intervention and 3-week follow-up. Eligible participants will be randomly allocated to the experimental group or the control group in a 1:1 ratio. After routine conventional physical therapy, patients in the experimental group will receive cerebellar vermis iTBS, whereas patients in the control group will receive sham stimulation. The overall intervention period will be 5 days a week for 3 consecutive weeks. The outcomes will be measured at baseline (T0), 3 weeks postintervention (T1) and at the 3-week follow-up (T2). The primary outcomes are Berg Balance Scale and Trunk Impairment Scale scores. The secondary outcomes are balance test scores via the Balance Master system, muscle activation of the trunk and lower limbs via the surface electromyography recordings, cerebral cortex oxygen concentrations measured via the resting-state functional near-infrared spectroscopy, Fugl-Meyer Assessment of Lower Extremity and Barthel index scores.

ETHICS AND DISSEMINATION

This study was approved by the West China Hospital Clinical Trials and Biomedical Ethics Committee of Sichuan University. All participants will sign the informed consent form voluntarily. The results of this study will be published in peer-reviewed journals and disseminated at academic conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2200065369.

The effects of anterior and posterior ankle-foot orthoses on sit-to-stand transfer performance in stroke patients

BACKGROUND

Nonarticulated and low-temperature thermoplastic ankle-foot orthoses (AFOs) have a semirigid design and are effective in improving the postural control mechanism (PCM) in individuals with poststroke hemiparesis. AFOs with an anterior leaf (AAFOs) are more often prescribed than are AFOs with a posterior leaf (PAFOs); however, the effects of AAFOs on the PCM during sit-to-stand transfer (STST) have not been explored.

RESEARCH QUESTIONS

Do AAFOs and PAFOs change the PCM differently during STST?

METHODS

A cross-sectional quasi-experimental design was adopted in this study. Fourteen individuals with poststroke hemiparesis (10 men and 4 women, aged between 38 and 71 years, stroke onset between 1 and 17 months) performed STST with shoes only, an AAFO with shoes, or a PAFO with shoes. Vertical ground reaction force (VGRF) and center-of-pressure (CoP) coordinates were collected using a pressure mat to calculate PCM parameters. A single-factor repeated measures analysis of variance was performed to answer the research question.

RESULTS

(1) The weight-bearing percentage of the paretic leg was significantly lower when the participants wore a PAFO (p = 0.018) than when they wore an AAFO (p = 0.019) during the first 5 and 5-10 s after rising. (2) A small rate of change of the VGRF increment (dF/dT) was detected when participants wore AFOs, particularly AAFO. (3) The maximum mediolateral displacement of the CoP when standing up was significantly different among the three conditions (p = 0.012).

SIGNIFICANCE

For patients with poststroke hemiparesis, AAFO and PAFOs change the PCM during STST performance. Only AAFO improved the PCM possibly because of the rigidity and clearance of the heel region, which provide somatic sensory feedback. Therefore, rehabilitation professionals should educate hemiplegic patients who use AAFOs or PAFOs to perform dynamic daily tasks slowly for their safety.

A new methodology based on functional principal component analysis to study postural stability post-stroke

BACKGROUND

A major goal in stroke rehabilitation is the establishment of more effective physical therapy techniques to recover postural stability. Functional Principal Component Analysis provides greater insight into recovery trends. However, when missing values exist, obtaining functional data presents some difficulties. The purpose of this study was to reveal an alternative technique for obtaining the Functional Principal Components without requiring the conversion to functional data beforehand and to investigate this methodology to determine the effect of specific physical therapy techniques in balance recovery trends in elderly subjects with hemiplegia post-stroke.

METHODS

A randomized controlled pilot trial was developed. Thirty inpatients post-stroke were included. Control and target groups were treated with the same conventional physical therapy protocol based on functional criteria, but specific techniques were added to the target group depending on the subjects' functional level. Postural stability during standing was quantified by posturography. The assessments were performed once a month from the moment the participants were able to stand up to six months post-stroke.

FINDINGS

The target group showed a significant improvement in postural control recovery trend six months after stroke that was not present in the control group. Some of the assessed parameters revealed significant differences between treatment groups (P < 0.05).

INTERPRETATION

The proposed methodology allows Functional Principal Component Analysis to be performed when data is scarce. Moreover, it allowed the dynamics of recovery of two different treatment groups to be determined, showing that the techniques added in the target group increased postural stability compared to the base protocol.

Rigid Ankle Foot Orthosis Deteriorates Mediolateral Balance Control and Vertical Braking during Gait Initiation

Rigid ankle-foot orthoses (AFO) are commonly used for impeding foot drop during the swing phase of gait. They also reduce pain and improve gait kinematics in patients with weakness or loss of integrity of ankle-foot complex structures due to various pathological conditions. However, this comes at the price of constraining ankle joint mobility, which might affect propulsive force generation and balance control. The present study examined the effects of wearing an AFO on biomechanical variables and electromyographic activity of tibialis anterior (TA) and soleus muscles during gait initiation (GI). Nineteen healthy adults participated in the study. They initiated gait at a self-paced speed with no ankle constraint as well as wearing an AFO on the stance leg, or bilaterally. Constraining the stance leg ankle decreased TA activity ipsilaterally during the anticipatory postural adjustment (APA) of GI, and ipsilateral soleus activity during step execution. In the sagittal plane, the decrease in the stance leg TA activity reduced the backward displacement of the center of pressure (CoP) resulting in a reduction of the forward velocity of the center of mass (CoM) measured at foot contact (FC). In the frontal plane, wearing the AFO reduced the displacement of the CoP in the direction of the swing leg during the APA phase. The mediolateral velocity of the CoM increased during single-stance prompting a larger step width to recover balance. During step execution, the CoM vertical downward velocity is normally reduced in order to lessen the impact of the swing leg with the floor and facilitates the rise of the CoM that occurs during the subsequent double-support phase. The reduction in stance leg soleus activity caused by constraining the ankle weakened the vertical braking of the CoM during step execution. This caused the absolute instantaneous vertical velocity of the CoM at FC to be greater in the constrained conditions with respect to the control condition. From a rehabilitation perspective, passively- or actively-powered assistive AFOs could correct for the reduction in muscle activity and enhance balance control during GI of patients.