Experimental Approach of Quadriceps Strength Measurement: Implications for Assessments in Critically Ill Survivors

(1) Background: The supine testing position is suitable for early quadriceps strength (QS) assessment in intensive care unit, while a seated position is more appropriate for survivors who have regained mobility. Acquiring consistent measurements is essential for longitudinal follow-up. We compared the QS generated in different settings in healthy volunteers. (2) Methods: Isometric QS was assessed using a MicroFet2 and standardised protocols comparing different modalities. Hip and knee flexion angles were, respectively, 45° and 40° (H45-K40) in the supine position, and both at 90° (H90-K90) in the seated position. Dynamometer was either handheld (non-fixed configuration, NFC), or fixed (FC) in a cubicle. (3) Results: QS in H90–K90 and H45-K40 positions were strongly correlated, but QS was higher in the later position regardless of the configuration. Compared to H45-K40, biases of 108.2N (or 28.05%) and 110.3N (27.13%) were observed in H90-K90 position, respectively, in the NFC and FC. These biases were independently and positively associated with QS (p < 0.001). For both position, there were no significant differences between QS measured in NFC or FC. (4) Conclusions: The quadriceps was less efficient in the seated position, compared to the supine position, in healthy volunteers. These findings have practical implications for further assessments and research in critically ill patients.

Evaluation of Gait Characteristics in Subjects With Locomotive Syndrome Using the Wearable Gait Sensors

Background: Locomotive syndrome (LS) is a condition where a person requires nursing care services due to problems with locomotive abilities and musculoskeletal systems. Individuals with LS have a reduced walking speed compared to those without LS. However, differences in lower-limb kinematics and during walking between individuals with and without LS are not fully understood. The purpose of this study is to clarify the characteristics of gait kinematics using wearable sensors for individuals with LS.Methods: We assessed 125 people aged 65 years and older who utilized a public health promotion facility. The participants were grouped into Non-LS, LS-stage 1, LS-stage 2 (large number indicate worse locomotive ability) based on 25-question Geriatric Locomotive Function Scale (GLFS-25). Spatiotemporal parameters and lower-limb kinematics during 10-m walking test were analyzed by 7-inertia-sensors based motion analysis system. Peak joint angles during stance and swing phase as well as gait speed, cadence and step length were compared among all groups.Results: The number of each LS stage was 69, 33, 23 for Non-LS, LS-stage 1, LS-stage 2, respectively. LS-stage2 group showed significantly smaller peak hip extension angle, hip flexion angle and knee flexion angle than Non-LS group (hip extension: Non-LS: 9.5 ± 5.3°, LS-stage 2: 4.2 ± 8.2°, P = 0.002; hip flexion: No-LS: 34.2 ± 8.8°, LS-stage 2: 28.5 ± 9.5°, P = 0.026; knee flexion: Non-LS: 65.2 ± 18.7°, LS-stage 2: 50.6 ± 18.5°, P = 0.005). LS-stage 1 and LS-stage 2 groups showed significantly slower gait speed than Non-LS group (Non-LS 1.3 ± 0.2 m/s, LS-stage1 1.2 ± 0.2 m/s, LS-stage2 1.1 ± 0.2 m/s, P < 0.001).Conclusions: LS-stage2 group showed significantly different lower-limb kinematics compared with Non-LS group including smaller hip extension, hip flexion and knee flexion. The intervention based on these kinematic characteristics measured by wearable sensors would be useful to improve the locomotive ability for individuals classified LS-stage2.

Effect of daily Vitamin D3 Supplementation on Muscle Health: An Individual Participant Meta-Analysis

Background The role of vitamin D on muscle health is debated. Methods An individual participant metanalysis of four randomized placebo-controlled trials, investigating short term (three to nine months) effects of vitamin D3 in moderate (2800 IU) to high (7000 IU) daily oral doses on muscle health and quality of life (QoL). Inclusion criteria were either obesity (N=52), newly diagnosed primary hyperparathyroidism (N=41), Graves’ disease (N=86) or secondary hyperparathyroidism (N=81). Results Overall (N=260) as well as in a subgroup analysis including only vitamin D insufficient (25(OH)D&lt; 50 nmol/L) individuals (N=176), vitamin D supplementation did not affect measures of muscle health (isometric muscle strength, Timed Up and Go test, Chair Rising Test, body composition, and balance) or QoL. However, a beneficial effect was present on QoL (physical component score) in vitamin D deficient (25(OH)D≤ 25 nmol/L) individuals (N=34). Overall, relative changes in 25(OH)D inversely affected maximum muscle strength in a dose response manner. Stratified into BMI &lt;/≥ 30 kg/m 2, vitamin D supplementation had divergent effects on isometric muscle strength, with beneficial effects in obese individuals (N=93) at knee flexion 90° (p=0.04), and adverse effects in non-obese individuals (N=167) at handgrip (p=0.02), knee extension 60° (p=0.03) and knee flexion 60° (p&lt;0.01). Conclusion Overall, short-term treatment with moderate to high daily doses of vitamin D did not affect muscle health or QoL. A potential beneficial effect was present on muscle strength in severe obese individuals and on QoL in vitamin D deficient individuals. Subgroup analyses however suggested negative effects of large relative increases in p-25(OH)D.

Analysis of Movement Entropy during Community Dance Programs for People with Parkinson’s Disease and Older Adults: A Cohort Study

Dance therapy can improve motor skills, balance, posture, and gait in people diagnosed with Parkinson’s disease (PD) and healthy older adults (OA). It is not clear how specific movement patterns during dance promote these benefits. The purpose of this cohort study was to identify differences and complexity in dance movement patterns among different dance styles for PD and OA participants in community dance programs using approximate entropy (ApEn) analysis. The hypothesis was that PD participants will show greater ApEn during dance than OA participants and that the unique dance style of tango with more pronounced foot technique and sharp direction changes will show greater ApEn than smoother dance types such as foxtrot and waltz characterized by gradual changes in direction and gliding movement with rise and fall. Individuals participated in one-hour community dance classes. Movement data were captured using porTable 3D motion capture sensors attached to the arms, torso and legs. Classes were also video recorded to assist in analyzing the dance steps. Movement patterns were captured and ApEn was calculated to quantify the complexity of movements. Participants with PD had greater ApEn in right knee flexion during dance movements than left knee flexion (p = 0.02), greater ApEn of right than left hip flexion (p = 0.05), and greater left hip rotation than right (p = 0.03). There was no significant difference in ApEn of body movements (p > 0.4) or mean body movements (p > 0.3) at any body-segment in OA. ApEn analysis is valuable for quantifying the degree of control and predictability of dance movements and could be used as another tool to assess the movement control of dancers and aid in the development of dance therapies.

Association between Kinesiophobia and Knee Pain Intensity, Joint Position Sense, and Functional Performance in Individuals with Bilateral Knee Osteoarthritis

In current clinical practice, fear of movement has been considered a significant factor affecting patient disability and needs to be evaluated and addressed to accomplish successful rehabilitation strategies. Therefore, the study aims (1) to establish the association between kinesiophobia and knee pain intensity, joint position sense (JPS), and functional performance, and (2) to determine whether kinesiophobia predicts pain intensity, JPS, and functional performance among individuals with bilateral knee osteoarthritis (KOA). This cross-sectional study included 50 participants (mean age: 67.10 ± 4.36 years) with KOA. Outcome measures: The level of kinesiophobia was assessed using the Tampa Scale of Kinesiophobia, pain intensity using a visual analog scale (VAS), knee JPS using a digital inclinometer, and functional performance using five times sit-to-stand test. Knee JPS was assessed in target angles of 15°, 30°, and 60°. Pearson’s correlation coefficients and simple linear regressions were used to analyze the data. Significant moderate positive correlations were observed between kinesiophobia and pain intensity (r = 0.55, p < 0.001), JPS (r ranged between 0.38 to 0.5, p < 0.05), and functional performance (r = 0.49, p < 0.001). Simple linear regression analysis showed kinesiophobia significantly predicted pain intensity (B = 1.05, p < 0.001), knee JPS (B ranged between 0.96 (0° of knee flexion, right side) to 1.30 (15° of knee flexion, right side)), and functional performance (B = 0.57, p < 0.001). We can conclude that kinesiophobia is significantly correlated and predicted pain intensity, JPS, and functional performance in individuals with KOA. Kinesiophobia is a significant aspect of the recovery process and may be taken into account when planning and implementing rehabilitation programs for KOA individuals.

Effect of the Knee and Hip Angles on Knee Extensor Torque: Neural, Architectural, and Mechanical Considerations

This study examined the influence of knee extensors’ hip and knee angle on force production capacity and their neuromuscular and architectural consequences. Sixteen healthy men performed sub-maximal and maximal voluntary isometric contractions (MVIC) of knee extensors with four different combinations of the knee and hip angles. Muscle architecture, excitation-contraction coupling process, muscular activity, and corticospinal excitability were evaluated on the vastus lateralis (VL) and rectus femoris (RF) muscles. MVIC and evoked peak twitch (Pt) torques of knee extensors increased significantly (p &lt; 0.05) by 42 ± 12% and 47 ± 16% on average, respectively, under knee flexed positions (110° flexion, 0° = full extension) compared to knee extended positions (20° flexion) but were not different between hip positions (i.e., 0° or 60° flexion). Knee flexion also affected VL and RF muscle and fascicle lengths toward greater length than under knee extended position, while pennation angle decreased for both muscles with knee flexion. Pennation angles of the VL muscle were also lower under extended hip positions. Alternatively, no change in maximal muscle activation or corticospinal activity occurred for the VL and RF muscles across the different positions. Altogether these findings evidenced that MVIC torque of knee extensors depended particularly upon peripheral contractile elements, such as VL and RF muscle and fascicle lengths, but was unaffected by central factors (i.e., muscle activation). Furthermore, the hip position can affect the pennation angle of the VL, while VL muscle length can affect the pennation angle of the RF muscle. These elements suggest that the VL and RF muscles exert a mutual influence on their architecture, probably related to the rectus-vastus aponeurosis.

Optical Sensor Assembly On Knee Brace For Continuous Knee Monitoring Application

Knee joint is an important part of human body. People with poor knee condition generally have limited physical movement, rendering to mental stress and agony. Knee pain can be categorized into three groups, known as acute injury, chronic injury and medical condition. Current technology to support the knee diagnosis and treatment procedures are limited to the use of manual goniometer, x-ray and magnetic resonance imaging (MRI). Alternative devices with continuous measurement capability for knee monitoring are minimum at this time, mainly due to the difficulties to cover the wide angle of the knee flexion. X-ray and MRI technologies are useful to have some insight on the knee problem, but they are not applicable for continuous monitoring. Aside from being expensive for general use of MRI, x-ray on the other hand can cause short-term side effects due to radiation exposure. The aim of this paper is to demonstrate the use of optical sensor integrated with mechanical gear system as a knee monitoring device. A plastic compartment, made by using 3D printer is used to place the sensor and the gear system. The design of the overall device allows direct attachment on a knee brace for easy placement on the knee. Based on current study, the proposed sensor has a range of motion between 0 deg. to 160 deg., 0.08 deg. resolution as well as support continuous monitoring of the knee. The sensor performance has been demonstrated for gait motion, ascending and descending stairs, sit-to-stand movement and maximum knee flexion applications.

Surgical Treatment of Leg Length Discrepancy and Knee Flexion Contracture Associated with a Congenital Absence of Quadriceps

We report the case of an 18-year-old male with congenital absence of quadriceps and hypoplasia of the patella who presented with a significant leg length discrepancy (LLD) and knee flexion contracture. Surgical management was aimed toward lengthening the limb, stabilizing the joint, and correcting the knee flexion contracture. Correction of a significant congenital LLD and knee flexion contracture poses challenges due to long-standing altered biomechanics. These are rare conditions for which no accepted surgical algorithms exist. It is essential to anticipate the biomechanical consequences of limb lengthening and flexion contracture correction that might arise and plan comprehensive interventions accordingly.

Investigating the Effect of Real-Time Center of Pressure (CoP) Feedback Training on the Swing Phase of Lower Limb Kinematics in Transfemoral Prostheses with SACH foot

Transfemoral amputee often encounters reduced toe clearance resulting in trip-related falls. Swing phase joint angles have been shown to influence the toe clearance therefore, training intervention that targets shaping the swing phase joint angles can potentially enhance toe clearance. The focus of this study was to investigate the effect of the shift in the location of the center of pressure (CoP) during heel strike on modulation of the swing phase joint angles in able-bodied participants (n=6) and transfemoral amputees (n=3). We first developed a real-time CoP-based visual feedback system such that participants could shift the CoP during treadmill walking. Next, the kinematic data were collected during two different walking sessions- baseline (without feedback) and feedback (shifting the CoP anteriorly/posteriorly at heel strike to match the target CoP location). Primary swing phase joint angle adaptations were observed with feedback such that during the mid-swing phase, posterior CoP shift feedback significantly increases (p&lt;0.05) the average hip and knee flexion angle by 11.55 degrees and 11.86 degrees respectively in amputees, whereas a significant increase (p&lt;0.05) in ankle dorsiflexion, hip and knee flexion angle by 3.60 degrees, 3.22 degrees, and 1.27 degrees respectively compared to baseline was observed in able-bodied participants. Moreover, an opposite kinematic adaptation was seen during anterior CoP shift feedback. Overall, results confirm a direct correlation between the CoP shift and the modulation in the swing phase lower limb joint angles.