The Effects of Ankle Position on Torque and Muscle Activity of the Knee Extensor During Maximal Isometric Contraction.

CONTEXT: It is very important to empirically determine the optimal ankle position for the quadriceps femoris (QF) strengthening during isometric exercises. OBJECTIVE: To examine the effect of different ankle positions on torque and electromyography (EMG) activity of QF during maximal isometric contraction. STUDY DESIGN: Within-subject repeated measures. SETTING: University laboratory. PARTICIPANTS: Thirty-six healthy volunteers (15 males and 21 females). MAIN OUTCOME MEASURES: The isometric strength of the QF was measured at 3 different ankle positions: active dorsiflexion (AD), active plantar flexion (AP), and neutral position (NP). Simultaneously, 3 different ankle positions were assessed for EMG activity of the vastus medialis, vastus lateralis, and rectus femoris muscles during maximal voluntary isometric contraction. RESULTS: The peak torque per body weight and average peak torque were significantly higher in AD than in AP and NP (P < .01). The vastus medialis and rectus femoris maximal voluntary isometric contraction EMG activity were significantly higher in AD than in AP and NP (P < .01). The vastus lateralis maximal voluntary isometric contraction EMG activity was significantly higher in AD than in AP and NP (P < .01), and was significantly higher in AP than in NP (P < .05). CONCLUSIONS: These results indicate that the 3 different ankle positions affect the QF torque and EMG activity. In particular, AD position may be more efficient for improving QF strength than AP and NP position. Future studies should prove whether long-term duration QF isometric exercise effects muscle strength and functional performance in different ankle positions.

Effects of Talocrural Mobilization with Movement on Ankle Strength, Mobility, and Weight-Bearing Ability in Hemiplegic Patients with Chronic Stroke: A Randomized Controlled Trial.

BACKGROUND AND OBJECTIVE: In general, adequate movement of the ankle joint is known to play an important role in functional activities. Stroke survivors frequently have limited range of motion of the ankle, leading to dysfunctional weight transfer toward the paretic lower limb during standing or gait. The purpose of this study was to investigate the effects of talocrural mobilization with movement (MWM) on ankle strength, dorsiflexion passive range of motion (DF-PROM), and weight-bearing ability on the paretic limb during standing or gait in stroke patients with limited ankle dorsiflexion. METHODS: Twenty-six participants with chronic hemiplegia (>6 months post stroke) were divided into 2 groups: MWM group (n = 13) and control group (n = 13). Both groups attended conventional physiotherapy sessions 3 times a week for 5 weeks. Additionally, the MWM group underwent talocrural MWM 3 times a week for 5 weeks. Isokinetic ankle strength, DF-PROM, and weight-bearing ability measures included the limit of stability (LOS); gait parameters were evaluated before and after interventions. RESULTS: Plantarflexors peak torque and DF-PROM significantly increased in the MWM group. In addition, forward and forward-paretic direction LOS significantly increased in the MWM group. Paretic direction LOS, single-limb support phase of the paretic limb significantly increased and double limb support phase significantly decreased within the MWM group. CONCLUSIONS: This study demonstrates that talocrural MWM has an augmented effect on ankle strength, mobility, and weight-bearing ability in chronic stroke patients with limited ankle motion when added to conventional therapy.

Relationship between dynamic balance and spatiotemporal gait symmetry in hemiplegic patients with chronic stroke.

BACKGROUND: Poor dynamic balance, which is common after stroke, may affect gait function. In particular, spatiotemporal asymmetrical gait patterns may occur in hemiplegic patients after stroke. OBJECTIVE: This study aimed to assess the relationship between dynamic balance and spatiotemporal gait symmetry in patients with chronic hemiplegic stroke. METHODS: To calculate symmetry ratios for step length (spatial parameter) and swing time (temporal parameter), 41 patients with chronic stroke walked at a comfortable speed. The dynamic balance measures included limit of stability (LOS) during standing and heel-to-heel base of support (H-H BOS) during gait. Analysis of correlations between various measures was performed. RESULTS: The overall LOS score correlated with temporal gait symmetry (r = 0.66). The forward, backward, paretic, and non-paretic direction LOS scores were related to temporal gait symmetry (r = 0.38-0.62). The H-H BOS was correlated with temporal (r = -0.63) and spatial (r = -0.36) gait symmetries. Other dynamic balance variables were not significantly correlated with spatial gait symmetry. CONCLUSION: Thus, control of dynamic balance abilities is related to the magnitude of temporal gait symmetry. This observation suggests that rehabilitation strategies that improve dynamic balance may enhance temporal gait symmetry in post-stroke patients.

Effects of visual fatigue caused by smartphones on balance function in healthy adults.

[Purpose] The purpose of this study was to determine the effects of visual fatigue caused by smartphone use on balance function. [Subjects and Methods] The participants consisted of 22 healthy male and female adults. Their postural stability, limit of stability, and limit of stability running time were evaluated using a computerized posturography apparatus before and after inducing visual fatigue. Postural stability and the limit of stability were divided into static and dynamic conditions. [Results] There were significant differences between the dynamic postural stability, the static and dynamic limit of stability, and both the static and dynamic limit of stability running times after the induction of visual fatigue. [Conclusion] The results showed that visual fatigue caused by smartphone use has a negative effect on balance function. Therefore, reducing visual fatigue through proper rest is necessary.

Effects of ankle joint mobilization with movement and weight-bearing exercise on knee strength, ankle range of motion, and gait velocity in patients with stroke: a pilot study.

[Purpose] The purpose of this study was to investigate the effects of ankle joint mobilization with movement on knee strength, ankle range of motion, and gait velocity, compared with weight-bearing exercise in stroke patients. [Subjects and Methods] Thirty subjects with chronic stroke were divided into three groups: MWM (n = 12), WBE (n = 8), and control (n = 10). All groups attended physical therapy sessions 3 times a week for 5 weeks. Subjects in the MWM group performed mobilization with movement exercises, whilst participants in the WBE group performed weight-bearing exercises. Knee peak torque, ankle range of motion, and spatiotemporal gait parameters were evaluated before and after the interventions. [Results] Knee extensor peak torque increased significantly in both MWM and WBE groups. However, only the MWM group showed significant improvement in passive and active ankle range of motion and gait velocity, among the three groups. [Conclusion] Ankle joint mobilization with movement intervention is more effective than simple weight-bearing intervention in improving gait speed in stroke patients with limited ankle motion.

Effects of sling-based manual therapy on cervicothoracic junction in patients with neck pain and forward head posture: A randomized clinical trial.

OBJECTIVE: The purpose of this study was to investigate the effect of 4 weeks of sling-based manual therapy on the cervicothoracic junction (CTJ) area in patients with neck pain and forward head posture. DESIGN: Single-blind randomized controlled trial. SETTING: Outpatient, Chonbuk National University hospital, Republic of Korea. SUBJECTS: A total of 22 participants with neck pain (Numeric Pain Rating Scale >3) and forward head posture (craniovertebral angle <51) were randomly assigned to a CTJ group or a control group (n = 11 each). INTERVENTION: In the control group, joint mobilization and motor control training was applied for the upper cervical spine (C0-C1). The CTJ group applied the same intervention to the upper cervical spine and cervicothoracic junction (C7-T3). MAIN MEASURES: Numeric pain rating scale and neck disability index, craniovertebral angle, active range of motion, and muscle activity were evaluated before and after 4 weeks of intervention. RESULT: The CTJ group participants showed significant improvement in the craniovertebral angle and cervical extension range after the intervention than the control group (P = 0.025, P = 0.001). While both groups presented significant differences after the intervention regarding Numeric pain rating scale, neck disability index, and muscle activity (sternocleidomastoid and anterior scalene muscle), there were no statistically significant differences between the groups (P > 0.05). CONCLUSION: Our results suggest that the CTJ and the upper cervical region in patients with neck pain and forward head posture represent an area which if approached by manual therapy, improves cervical mobility and posture.

Effect of postural training using a whole-body tilt apparatus in subacute stroke patients with lateropulsion: A single-blinded randomized controlled trial.

BACKGROUND: Lateropulsion after stroke is defined as a postural bias toward the paretic side and push away from the non-paretic side. New rehabilitation techniques and programs should be designed to attenuate lateropulsion and improve functions of balance and gait. OBJECTIVE: This study aimed to determine the effects of whole-body tilting postural training (WTPT) using a Spine Balance 3D on lateropulsion and postural control as compared with general postural training (GPT). Postural training was performed and involved a whole-body tilt apparatus that enables postural training in the tilted position, in multiple directions. METHODS: This was a pragmatic, single-blind, randomized controlled trial conducted between June 2018 and May 2019. We randomly allocated 30 patients with subacute stroke and lateropulsion based on the Scale of Contraversive Pushing (SCP score>0) to experimental (n=15) and control (n=15) groups. The experimental group received WTPT with a whole-body tilt apparatus, and the control group GPT. WTPT was performed with the Spine Balance 3D and GPT with postural training commonly applied in the clinic. All participants received treatment for 30min/session, 2 times/day, 5 days/week for 3 weeks. The primary outcome measure was lateropulsion assessed with the Burke Lateropulsion Scale (BLS). Secondary outcome measures were postural control ability, activities of daily living, Postural Assessment Scale for Stroke (PASS) score, Berg Balance Scale (BBS) score, Korea-modified Barthel index (K-MBI), and Fugl-Meyer Motor Assessment-Lower Extremity (FMA-L) score. RESULTS: For the primary outcome, after training, BLS scores were decreased more for the experimental than control group (Δ=-5.8 vs. Δ=-4.2, P=0.002). For secondary outcomes, scores were improved more for the experimental than control group: PASS (Δ=13.8 vs. Δ=8.5, P<0.001), BBS (Δ=20.1 vs. Δ=11.1, P=0.001), K-MBI (Δ=27.0 vs. Δ=20.1, P=0.005), and FMA-L (Δ=10.2 vs. Δ=6.3, P=0.002). CONCLUSIONS: WTPT is a potentially effective therapeutic intervention for lateropulsion recovery in patients with subacute stroke. It may be useful for improving postural control and activities of daily living.

The effects of semi-immersive virtual reality therapy on standing balance and upright mobility function in individuals with chronic incomplete spinal cord injury: A preliminary study.

BACKGROUND: Individuals with chronic incomplete spinal cord injury (iSCI) commonly face persistent balance or mobility impairments. Virtual reality (VR) therapy is a useful rehabilitation approach; however, little is known about its effects in individuals with chronic iSCI. OBJECTIVE: To investigate the effects of semi-immersive VR therapy on standing balance and upright mobility function in individuals with chronic iSCI. METHODS: Ten subjects with chronic iSCI underwent VR therapy 30 minutes a day, 3 days a week, for 6 weeks. Limit of stability (LOS) and the Berg Balance Scale (BBS) were used to evaluate standing balance function. The Timed Up & Go (TUG) test, Activities-specific Balance Confidence (ABS) Scale, and Walking Index for Spinal Cord Injury-II (WISCI-II) were used to measure the subject's upright mobility function. Outcomes were assessed and recorded pre- and post-intervention. RESULTS: After semi-immersive VR therapy, LOS and BBS scores were significantly increased. In addition, the TUG test results increased significantly over time, while ABC scale scores and WSCI-II levels improved significantly. CONCLUSION: This study is the first to assess the effects of semi-immersive VR therapy for patients with chronic iSCI and limited functional abilities. These results indicated that semi-immersive VR therapy has a positive effect and is a useful intervention for standing balance and upright mobility function in patients with chronic iSCI.