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Journal of Bodywork and Movement... Jul 2024Intrinsic foot muscles (IFMs) play an important role in lower-limb motor control, including biomechanics and neuromuscular control function. Short foot exercise (SFE)... (Randomized Controlled Trial)
Randomized Controlled Trial
INTRODUCTION
Intrinsic foot muscles (IFMs) play an important role in lower-limb motor control, including biomechanics and neuromuscular control function. Short foot exercise (SFE) and toe curl exercise (TC) are methods used to train the IFMs, but their effect on lower-limb motor control has not been reported in previous studies. This study evaluated the effects of SFE and TC on lower-limb motor control function during single-leg standing (SLS).
TRIAL DESIGN
Randomized control trial.
METHOD
Thirty-six participants with flatfoot were randomly assigned to the SFE or TC group and performed exercise for 8 weeks. The assessment items were navicular drop test, toe grip strength (TGS), plantar sensation, and SLS. In the SLS assessment, we measured the mean center of pressure (COP) amplitude in the anteroposterior (AP) and mediolateral (ML) directions, onset time of gluteus maximus (G. max) and gluteus medius (G. med), angle of forefoot/hindfoot protonation and hip adduction, and lateral pelvic shift. Mixed-model repeated-measures analysis of variance and Bonferroni corrections were performed in statistical analysis.
RESULTS
The SFE group showed significant differences between pre- and post-intervention for TGS (p < 0.001), COP ML (p = 0.039), and onset times of G. max (p = 0.015), and G. med (p < 0.001). The TC group showed no significant differences in all assessment items.
CONCLUSION
Our finding suggests that SFE contributes to lower neuromuscular control function in people with flatfoot.
TRIAL REGISTRATION
UMIN000049963.
Topics: Humans; Male; Female; Young Adult; Flatfoot; Exercise Therapy; Muscle, Skeletal; Foot; Adult; Postural Balance; Lower Extremity; Standing Position; Biomechanical Phenomena; Muscle Strength
PubMed: 38876641
DOI: 10.1016/j.jbmt.2024.02.023 -
Technology and Health Care : Official... Jun 2024Standing is a basic human function that healthy adults take for granted, yet it is a complex perceptual-motor process that requires sensation of position and motion from...
BACKGROUND
Standing is a basic human function that healthy adults take for granted, yet it is a complex perceptual-motor process that requires sensation of position and motion from the sensory systems.
OBJECTIVE
We assessed agreement between center of pressure data from a laboratory force-platform and head position data from an HTC Vive head-mounted display (HMD) for the evaluation of standing postural control. We investigated the impact of different statistical choices when assessing the relationship between two measurements. Specifically: 1) How does correlation and agreement statistics relate before and after logarithmic transformation? 2) Is there systemic or proportional bias between the force-platform and HMD measurements?
METHODS
We tested 37 adults (26 controls, 11 with unilateral vestibular hypofunction) standing on foam, observing a static or dynamic visual scene projected from the HMD. We quantified anterior-posterior and medio-lateral sway via Directional Path, Root Mean Square Velocity, Variance, and Power Spectral Density (PSD) from a force-platform and the HMD.
RESULTS
Intra-class correlations (ICCs) were moderate-to-good for the non-transformed data and good-to-excellent after logarithmic transformation for all outcomes except for PSD above 1 Hz. Correlations were higher than ICCs. Bland-Altman plots indicated proportional bias but not after logarithmic transformation.
CONCLUSIONS
Both devices correlated linearly, and measure people's postural responses but cannot be used interchangeably, mostly because they appear to diverge with larger sway as evident on Bland-Altman plots of non-transformed data. Agreement between devices was excellent for low frequency movement but poor for high frequency small corrective movements.
PubMed: 38875054
DOI: 10.3233/THC-231338 -
PloS One 2024Standing up from a chair is a key daily life activity that is sensitive to functional limitations as we age and associated with falls, frailty, and institutional living....
Standing up from a chair is a key daily life activity that is sensitive to functional limitations as we age and associated with falls, frailty, and institutional living. Predictive neuromusculoskeletal models can potentially shed light on the interconnectivity and interdependency of age-related changes in neuromuscular capacity, reinforcement schemes, sensory integration, and adaptation strategies during stand-up. Most stand-up movements transfer directly into walking (sit-to-walk). The aim of this study was to develop and validate a neuromusculoskeletal model with reflex-based muscle control that enables simulation of the sit-to-walk movement under various conditions (seat height, foot placement). We developed a planar sit-to-walk musculoskeletal model (11 degrees-of-freedom, 20 muscles) and neuromuscular controller, consisting of a two-phase stand-up controller and a reflex-based gait controller. The stand-up controller contains generic neural pathways of delayed proprioceptive feedback from muscle length, force, velocity, and upper-body orientation (vestibular feedback) and includes both monosynaptic an antagonistic feedback pathways. The control parameters where optimized using a shooting-based optimization method, based on a high-level optimization criterium. Simulations were compared to recorded kinematics, ground reaction forces, and muscle activation. The simulated kinematics resemble the measured kinematics and muscle activations. The adaptation strategies that resulted from alterations in seat height, are comparable to those observed in adults. The simulation framework and model are publicly available and allow to study age-related compensation strategies, including reduced muscular capacity, reduced neural capacity, external perturbations, and altered movement objectives.
Topics: Humans; Walking; Biomechanical Phenomena; Movement; Muscle, Skeletal; Models, Biological; Computer Simulation; Gait; Adaptation, Physiological; Sitting Position
PubMed: 38870249
DOI: 10.1371/journal.pone.0305328 -
Spine Surgery and Related Research May 2024Studies describing the relationship between the hip and spine have reported that corrective spinal surgery for adult spinal deformity (ASD) affects the orientation of...
INTRODUCTION
Studies describing the relationship between the hip and spine have reported that corrective spinal surgery for adult spinal deformity (ASD) affects the orientation of the acetabulum. However, the extent to which spinal correction in ASD affects acetabular anteversion in the standing position is unclear, especially after total hip arthroplasty, for which dislocation is a concern. The purpose of this study was to evaluate changes in anterior acetabular coverage in the upright position due to extensive correction surgery for ASD.
METHODS
Thirty-six consecutive patients who had undergone spinal corrective surgery from the thoracolumbar region to the pelvis were enrolled and evaluated. The ventral-central-acetabular (VCA) angle and anterior acetabular head index (AAHI) were measured with a false-profile view to evaluate the relationship between acetabular anteversion in the standing position and spinopelvic parameters before and after surgery. The spinopelvic parameters measured included thoracic kyphosis, pelvic incidence, pelvic tilt (PT), sacral slope, lumbar lordosis (LL), sagittal vertical axis, and global tilt.
RESULTS
The VCA angle and AAHI were significantly increased after spinal deformity correction (p<0.001). The changes in LL and PT were correlated with the VCA angle (LL: right, ρ=0.56; left, ρ=0.55, p<0.001; PT: right, ρ=-0.59; left, ρ=-0.64, p<0.001) and AAHI (LL: right, ρ=0.51; left, ρ=0.58, p<0.01; PT: right, ρ=-0.52; left, ρ=-0.59, p<0.01), respectively. Linear regression analysis revealed that a 10° increase in LL results in 1.4°-1.9° and 1.6%-2% increases in the VCA angle and AAHI, respectively.
CONCLUSIONS
Surgical correction for ASD significantly affects sagittal spinopelvic parameters, resulting in increased acetabular anteversion. The anterior coverage of the acetabulum in the postoperative standing position could be predicted with the intraoperatively measured LL, and evaluation using a false-profile was considered useful for treating ASD, particularly in patients after total hip arthroplasty.
PubMed: 38868798
DOI: 10.22603/ssrr.2023-0273 -
Frontiers in Medicine 2024Pregnancy introduces significant physiological changes, notably impacting respiratory dynamics, especially during the second trimester. Data remain inconclusive about...
BACKGROUND
Pregnancy introduces significant physiological changes, notably impacting respiratory dynamics, especially during the second trimester. Data remain inconclusive about how body posture might influence lung function in pregnant women. We aimed to examine the impact of body position on slow vital capacity in pregnant women during their second trimester.
METHODS
This observational study was carried out at King Khalid Hospital in Saudi Arabia, involving pregnant women in their second trimester, from 14 to 26 weeks of gestation. We utilized the KoKo® Legend Portable Office Spirometer to measure slow vital capacity (SVC) in both sitting and standing positions. Participants' demographic details were recorded, ensuring a comprehensive analysis that accounted for age, BMI, and gestational age.
RESULTS
136 pregnant women participated in this study, a paired-sample -test revealed no statistically significant difference between sitting (M = 2.31, SD = 0.49) and standing (M = 2.33, SD = 0.5) positions, = 0.24, However; the mean value of SVC in sitting position was significantly different between 4th month of pregnancy (M = 2.17, SD = 0.44) and 6th month of pregnancy (M = 2.45, SD = 0.48), = 0.016.
CONCLUSION
The performance of the SVC in both positions was not significantly affected. However, an increase in gestational age had a notable impact on SVC performance, particularly during sitting positions, due to the changes in respiratory physiology during pregnancy.
PubMed: 38863888
DOI: 10.3389/fmed.2024.1351681 -
Journal of Neuro-ophthalmology : the... Jun 2024Among the symptoms seen in idiopathic intracranial hypertension (IIH), hemifacial spasm (HFS) is rare. Orthostatic-induced HFS preceding lumbar puncture (LP) is...
BACKGROUND
Among the symptoms seen in idiopathic intracranial hypertension (IIH), hemifacial spasm (HFS) is rare. Orthostatic-induced HFS preceding lumbar puncture (LP) is previously unreported. We treated two patients with unusual IIH presentations. This case series reviews the few reports of HFS in IIH and proposes a mechanism for spasm occurrence.
METHODS
Case 1: A woman in her mid-40s with previously controlled IIH developed daily headache, pulsatile tinnitus, right-sided trigeminal paresthesia, and right-sided HFS. The latter 2 symptoms occurred exclusively when moving from a sitting to a standing position. Imaging was unremarkable; opening pressure (OP) on LP was 46 cmH2O with normal cerebrospinal fluid (CSF) components. Case 2: A woman in her late 40s presented with severe daily headache, pulsatile tinnitus, and left-sided HFS following weight gain. Imaging was unremarkable; OP on LP was 32 cmH2O with normal CSF components.
RESULTS
HFS episodes persisted following LP in both patients. Increasing and initiating acetazolamide, respectively, resolved all symptoms.
CONCLUSIONS
Earlier suggested mechanisms of HFS are based on elevated intracranial pressure (ICP) shifting the facial nerve into proximity of a vascular structure. HFS appearing upon standing and continuing after LP, and thus a lower ICP, contradicts this. We propose a mechanism based on the degree of ICP change. This theory is grounded in the lack of intracranial compliance in IIH, wherein substantial pressure changes occur following small volume changes.
PubMed: 38863112
DOI: 10.1097/WNO.0000000000002187 -
BMC Musculoskeletal Disorders Jun 2024Sit-to-stand (STS) is one of the most commonly performed functional movements in a child's daily life that enables the child to perform functional activities such as...
BACKGROUND
Sit-to-stand (STS) is one of the most commonly performed functional movements in a child's daily life that enables the child to perform functional activities such as independent transfer and to initiate walking and self-care. Children with cerebral palsy (CP) often have reduced STS ability. The aim of this study was to describe STS performance in a national based total population of children with CP and its association with age, sex, Gross Motor Function Classification System (GMFCS) level, and CP subtype.
METHODS
This cross-sectional study included 4,250 children (2,503 boys, 1,747 girls) aged 1-18 years from the Swedish Cerebral Palsy Follow-Up Program (CPUP). STS performance was classified depending on the independence or need for support into "without support," "with support," or "unable." "With support" included external support from, e.g., walls and furniture. Physical assistance from another person was classified as "unable" (dependent). Ordinal and binary logistic regression analyses were used to identify associations between STS and age, GMFCS level, and CP subtype.
RESULTS
60% of the children performed STS without support, 14% performed STS with support, and 26% were unable or needed assistance from another person. STS performance was strongly associated with GMFCS level and differed with age and subtype (p < 0.001). For all GMFCS levels, STS performance was lowest at age 1-3 years. Most children with GMFCS level I (99%) or II (88%) performed STS without support at the age of 4-6 years. In children with GMFCS level III or IV, the prevalence of independent STS performance improved throughout childhood. CP subtype was not associated with STS performance across all GMFCS levels when adjusted for age.
CONCLUSIONS
Independent STS performance in children with CP is associated with GMFCS level and age. Children with CP acquire STS ability later than their peers normally do. The proportion of children with independent STS performance increased throughout childhood, also for children with GMFCS level III or IV. These findings suggest the importance of maintaining a focus on STS performance within physiotherapy strategies and interventions for children with CP, including those with higher GMFCS level.
Topics: Humans; Cerebral Palsy; Cross-Sectional Studies; Male; Female; Child; Child, Preschool; Adolescent; Sweden; Infant; Sitting Position; Standing Position; Motor Skills; Activities of Daily Living
PubMed: 38862936
DOI: 10.1186/s12891-024-07557-0 -
IEEE Transactions on Neural Systems and... 2024Postural control is one of the primary body functions for fall prevention. Unexpected perturbation-based balance training is effective for improving postural control....
Postural control is one of the primary body functions for fall prevention. Unexpected perturbation-based balance training is effective for improving postural control. However, the effect of perturbation-based training using assistive devices on muscle activity and co-contraction for standing balance is still unclear. This training is also difficult to perform easily because it requires large instruments or expert guidance. The purpose of this study is to demonstrate the effect of perturbation-based balance training using a wearable balance training device (WBTD) on postural control. In this study, fourteen healthy young adult males were assigned to either a WBTD group or a sham group. In the intervention session, participants in the WBTD group were perturbed either left or right direction at random timing by the WBTD during tandem stance balance training. Participants in the Sham group did not receive external perturbation during tandem stance balance training. Before and after the intervention session, participants of both groups underwent unexpected lateral perturbation postural control testing (pre- and post-test). The normalized integral of electromyography (IEMG), co-contraction index (CCI), and center of pressure (COP) parameters were measured in the pre- and post-test. Experimental results showed that the WBTD group in the post-test significantly decreased left Gluteus Medius IEMG, CCI of both Gluteus Medius, and peak [Formula: see text] velocity, compared to those of the pre-test ( [Formula: see text], p =0.024 , p =0.031 , respectively). We conclude that balance training using WBTD could improve flexible postural control adjustment via cooperative muscle activation.
Topics: Humans; Male; Postural Balance; Electromyography; Young Adult; Muscle, Skeletal; Muscle Contraction; Wearable Electronic Devices; Adult; Standing Position; Healthy Volunteers
PubMed: 38861447
DOI: 10.1109/TNSRE.2024.3412686 -
European Spine Journal : Official... Jun 2024The goal of this study was to explore sex-related variations of global alignment parameters and their distinct evolution patterns across age groups.
PURPOSE
The goal of this study was to explore sex-related variations of global alignment parameters and their distinct evolution patterns across age groups.
METHODS
This multicentric retrospective study included healthy volunteers with full-body biplanar radiographs in free-standing position. All radiographic data were collected from 3D reconstructions: global and lower limb parameters, pelvic incidence (PI) and sacral slope (SS). Lumbar lordosis (LL), thoracic kyphosis (TK) and cervical lordosis (CL) were also assessed as well as the lumbar and thoracic apex, and thoracolumbar inflexion point. The population was divided into five 5 age groups: Children, Adolescents, Young, Middle-Aged and Seniors.
RESULTS
This study included 861 subjects (53% females) with a mean age of 34 ± 17 years. Mean PI was 49.6 ± 11.1 and mean LL was - 57.1 ± 11.6°. Females demonstrated a PI increase between Young and Middle-Aged groups (49 ± 11° vs. 55 ± 12°, p < 0.001) while it remained stable in males. SS and LL increased with age in females while remaining constant in males between Children and Middle-aged and then significantly decreased for both sexes between Middle-Aged and Seniors. On average, lumbar apex, inflexion point, and thoracic apex were located one vertebra higher in females (p < 0.001). After skeletal maturity, males had greater TK than females (64 ± 11° vs. 60 ± 12°, p = 0.04), with significantly larger CL (-13 ± 10° vs. -8 ± 10°, p = 0.03). All global spinal parameters indicated more anterior alignment in males.
CONCLUSION
Males present more anteriorly tilted spine with age mainly explained by a PI increase in females between Young and Middle-Aged, which may be attributed to childbirth. Consequently, SS and LL increased before decreasing at senior age.
PubMed: 38858268
DOI: 10.1007/s00586-024-08323-5 -
Journal of Hand and Microsurgery Jun 2024Approximately 68% of orthopaedic surgeons report occupational related musculoskeletal pain, with back pain being the most common. Poor posture while operating has been...
OBJECTIVE
Approximately 68% of orthopaedic surgeons report occupational related musculoskeletal pain, with back pain being the most common. Poor posture while operating has been proven to contribute to these high rates of musculoskeletal pain. There is little research regarding intraoperative surgeon posture within the field of hand and upper extremity surgery. This prospective study aims to investigate and analyze hand surgeon posture in the operating room.
METHODS
Posture of three hand surgeons was recorded using the UPRIGHT GO posture tracking device while performing a prospective series of 223 hand and upper extremity surgeries. This device reports posture in terms of overall percentage of time spent slouched versus upright. For this cohort of 223 cases, data were collected including surgical procedure, whether the surgery was performed in a seated or standing position, whether or not loupes were worn during the procedure, and if the surgeon was the primary or assistant surgeon. These data were then analyzed to look for any contributing factors to poor posture.
RESULTS
The three hand surgeons in this study spent an average of 40.3% of their time slouched while operating. The average percentage of time slouched was significantly greater with the use of loupes versus no loupes. Additionally, mean time slouching was slightly increased when the surgeon was seated and also when the surgeon was acting as the assistant surgeon.
CONCLUSION
The three orthopaedic hand surgeons in our study spent a significant portion of their operative time slouched. The main variable associated with a significant risk of poor surgical posture was wearing loupes. Slight increases in slouching were seen with operating while seated and as the assistant surgeon. Surgeon awareness of these variables, as well as techniques to improve surgeon posture, should be developed in order to help contribute to better surgeon posture within the field of hand surgery.
PubMed: 38855511
DOI: 10.1055/s-0043-1771228