Reliability and validity of the ankle inversion discrimination apparatus during walking in individuals with chronic ankle instability

Purpose: 1) to explore the test-retest reliability of a new device for measuring ankle inversion proprioception during walking, i.e., the Ankle Inversion Discrimination Apparatus-Walking (AIDAW) in individuals with or without Chronic Ankle instability (CAI); 2) to assess its discriminant validity in differentiating individuals with or without CAI; 3) to investigate its convergent validity by examining its association with Cumberland Ankle Instability Tool (CAIT) and the Y Balance Test (YBT). Methods: For test-retest reliability, 15 participants with CAI and 15 non-CAI healthy controls were recruited. Participants completed the AIDAW test twice with a 7-day interval. The area under the receiver operating curve (AUC) was obtained as the AIDAW score. The intraclass correlation coefficient (ICC) and MDC₉₀ were calculated. For the validity study, another 20 individuals with CAI and 20 non-CAI healthy controls were involved. The AIDAW scores were analyzed by an independent samples t-test, and the optimal cutoff value of AIDAW scores to best distinguish individuals with CAI was calculated by Youden's index. Spearman or Pearson correlation analysis was used to analyze the correlation between AIDAW proprioceptive scores and the CAIT and final YBT scores. Results: For test-retest reliability, the ICC values for the CAI, non-CAI, and the whole group were 0.755, 0.757, and 0.761 respectively. The MDC₉₀ of the CAI and non-CAI group was 0.04 and 0.05. Regarding discriminant validity, the AIDAW proprioceptive discrimination scores in the CAI group were significantly lower than those in the non-CAI group (p = 0.003); and the cutoff score for distinguishing CAI from the non-CAI participants was 0.759. For convergent validity, the AIDAW scores were significantly correlated with the functional balance YBT final scores (p = 0.001) and the CAIT scores (p = 0.009). Conclusion: The AIDAW is a reliable and valid device for evaluating ankle inversion proprioception during walking in individuals with and without CAI. AIDAW can be used as a clinical assessment tool to discriminate CAI from non-CAI individuals and to monitor effects of rehabilitation. The AIDAW proprioceptive discrimination scores were significantly and positively correlated with YBT and CAIT scores.

Right hemisphere brain lateralization for knee proprioception among right-limb dominant individuals

Introduction

Studies indicate that brain response during proprioceptive tasks predominates in the right hemisphere. A right hemisphere lateralization for proprioception may help to explain findings that right-limb dominant individuals perform position matching tasks better with the non-dominant left side. Evidence for proprioception-related brain response and side preference is, however, limited and based mainly on studies of the upper limbs. Establishing brain response associated with proprioceptive acuity for the lower limbs in asymptomatic individuals could be useful for understanding the influence of neurological pathologies on proprioception and locomotion.

Methods

We assessed brain response during an active unilateral knee joint position sense (JPS) test for both legs of 19 right-limb dominant asymptomatic individuals (females/males = 12/7; mean ± SD age = 27.1 ± 4.6 years). Functional magnetic resonance imaging (fMRI) mapped brain response and simultaneous motion capture provided real-time instructions based on kinematics, accurate JPS errors and facilitated extraction of only relevant brain images.

Results

Significantly greater absolute (but not constant nor variable) errors were seen for the dominant right knee (5.22° ± 2.02°) compared with the non-dominant left knee (4.39° ± 1.79°) (P = 0.02). When limbs were pooled for analysis, significantly greater responses were observed mainly in the right hemisphere for, e.g., the precentral gyrus and insula compared with a similar movement without position matching. Significant response was also observed in the left hemisphere for the inferior frontal gyrus pars triangularis. When limbs were assessed independently, common response was observed in the right precentral gyrus and superior frontal gyrus. For the right leg, additional response was found in the right middle frontal gyrus. For the left leg, additional response was observed in the right rolandic operculum. Significant positive correlations were found between mean JPS absolute errors for the right knee and simultaneous brain response in the right supramarginal gyrus (r = 0.464, P = 0.040).

Discussion

Our findings support a general right brain hemisphere lateralization for proprioception (knee JPS) of the lower limbs regardless of which limb is active. Better proprioceptive acuity for the non-dominant left compared with the dominant right knee indicates that right hemisphere lateralization may have meaningful implications for motor control.

Relationship of strength, joint kinesthesia, and plantar tactile sensation to dynamic and static postural stability among patients with anterior cruciate ligament reconstruction

Objective: Postural stability is essential for high-level physical activities after anterior cruciate ligament reconstruction (ACLR). This study was conducted to investigate the relationship of muscle strength, joint kinesthesia, and plantar tactile sensation to dynamic and static postural stability among patients with anterior cruciate ligament reconstruction. Methods: Forty-four patients over 6 months post anterior cruciate ligament reconstruction (age: 27.9 ± 6.8 years, height: 181.7 ± 8.7 cm, weight: 80.6 ± 9.4 kg, postoperative duration: 10.3 ± 3.6 months) participated in this study. Their static and dynamic postural stability, muscle strength, hamstring/quadriceps ratio, joint kinesthesia, and plantar tactile sensation were measured. Partial correlations were used to determine the correlation of the above-mentioned variables with time to stabilization (TTS) and root mean square of the center of pressure (COP-RMS) in anterior-posterior (AP) and mediolateral (ML) directions. Results: Both TTS_AP and TTS_ML were related to muscle strength and joint kinesthesia of knee flexion and extension; COP-RMS_AP was correlated with plantar tactile sensations at great toe and arch, while COP-RMS_ML was correlated with joint kinesthesia of knee flexion, and plantar tactile sensation at great toe and heel. Dynamic stability was sequentially correlated with strength and joint kinesthesia, while static stability was sequentially correlated with plantar tactile sensation and joint kinesthesia. Conclusion: Among patients with anterior cruciate ligament reconstruction, strength is related to dynamic postural stability, joint kinesthesia is related to dynamic and static postural stability, and plantar tactile sensation is related to static postural stability. Strength has a higher level of relationship to dynamic stability than joint kinesthesia, and plantar tactile sensation has a higher level of relationship to static stability than joint kinesthesia.

Protocol for a prospective multicenter longitudinal randomized controlled trial (CALIN) of sensory-tonic stimulation to foster parent child interactions and social cognition in very premature infants

Introduction

Premature birth is associated with long-term somatic and neurological disorders, including cognitive, social and behavioral impairments. Moreover, the mothers of infants born preterm exhibit a higher prevalence of anxiety and depressive symptoms after birth. Early rehabilitation, developmental care, and parenting support have already been shown to have a positive impact on neurological outcome. However, no randomized controlled study has so far assessed the effects on parenting and long-term neurological outcomes of proprioceptive stimulation to trigger positive brain plasticity in very preterm babies. The CALIN project will therefore investigate the impact of sensory-tonic stimulation (STS) of extremely preterm infants by their parents on child parent interactions, infants' morphological and functional brain development and subsequent cognition (including social cognition), and parents' anxiety and depressive symptoms in the postpartum period.

Methods and analysis

Infants born between 25 and 32 weeks of gestation will be randomly assigned to the "STS + Kangaroo care" or "Kangaroo care" group. The primary endpoint, child and parent interactions, will be rated at 12 months corrected age using the Coding Interactive Behavior system. Secondary endpoints include: 1/functional and anatomical brain maturation sequentially assessed during neonatal hospitalization using electroencephalogram (EEG), amplitude-integrated EEG (aEEG), cranial ultrasound and MRI performed at term-corrected age, 2/social and cognitive outcomes assessed at 15 months, 2, 4 and 6 years, and 3/parents' anxiety and depressive symptoms assessed at 7 ± 1 weeks after birth, using dedicated questionnaires.

Ethics and dissemination

This study was approved by the French Ethics Committee for the Protection of Persons on 18 October 2021. It is registered with the French National Agency for the Safety of Medicines and Health Products (ANSM; no. 2020-A00382-37). The registry number on ClinicalTrials.gov is NCT04380051.

Sensorimotor feedback loops are selectively sensitive to reward

Although it is well established that motivational factors such as earning more money for performing well improve motor performance, how the motor system implements this improvement remains unclear. For instance, feedback-based control, which uses sensory feedback from the body to correct for errors in movement, improves with greater reward. But feedback control encompasses many feedback loops with diverse characteristics such as the brain regions involved and their response time. Which specific loops drive these performance improvements with reward is unknown, even though their diversity makes it unlikely that they are contributing uniformly. We systematically tested the effect of reward on the latency (how long for a corrective response to arise?) and gain (how large is the corrective response?) of seven distinct sensorimotor feedback loops in humans. Only the fastest feedback loops were insensitive to reward, and the earliest reward-driven changes were consistently an increase in feedback gains, not a reduction in latency. Rather, a reduction of response latencies only tended to occur in slower feedback loops. These observations were similar across sensory modalities (vision and proprioception). Our results may have implications regarding feedback control performance in athletic coaching. For instance, coaching methodologies that rely on reinforcement or 'reward shaping' may need to specifically target aspects of movement that rely on reward-sensitive feedback responses.

Muscle spindles and their role in maintaining robust locomotion

Muscle spindles, one of the two main classes of proprioceptors together with Golgi tendon organs, are sensory structures that keep the central nervous system updated about the position and movement of body parts. Although they were discovered more than 150 years ago, their function during movement is not yet fully understood. Here, we summarize the morphology and known functions of muscle spindles, with a particular focus on locomotion. Although certain properties such as the sensitivity to dynamic and static muscle stretch are long known, recent advances in molecular biology have allowed the characterization of the molecular mechanisms for signal transduction in muscle spindles. Building upon classic literature showing that a lack of sensory feedback is deleterious to locomotion, we bring to the discussion more recent findings that support a pivotal role of muscle spindles in maintaining murine and human locomotor robustness, defined as the ability to cope with perturbations. Yet, more research is needed to expand the existing mechanistic understanding of how muscle spindles contribute to the production of robust, functional locomotion in real world settings. Future investigations should focus on combining different animal models to identify, in health and disease, those peripheral, spinal and brain proprioceptive structures involved in the fine tuning of motor control when locomotion happens in challenging conditions.

Effects of end-effector robot-assisted gait training on gait ability, muscle strength, and balance in patients with spinal cord injury

BACKGROUND

There is no randomized controlled study about the effects of end-effector robot-assisted gait training (RAGT) in patients with spinal cord injury (SCI).

OBJECTIVE

To examine the effects of end-effector RAGT on gait and balance abilities in SCI.

METHODS

Thirty-one patients were randomly assigned to the RAGT (Morning Walk®, Curexo, Seoul, South Korea) or conventional therapy (CT) group. Patients were assessed using the 10-meter walk test (10MWT), 6-minute walk test (6mWT), lower extremity motor score (LEMS) and proprioception, Berg Balance Scale (BBS), Walking Index for Spinal Cord Injury-II (WISCI-II), and mobility category of Spinal Cord Independence Measure-III.

RESULTS

All clinical outcome measures significantly improved in both groups. The BBS and WISCI-II were significantly improved in the RAGT group compared to the CT group. In the RAGT group, pre-LEMS and pre-WISCI-II of the 10MWT improved group and pre-BBS of the 6mWT improved group were higher than those of the 10MWT non-improved and 6mWT non-improved group, respectively.

CONCLUSION

End-effector RAGT and CT in patients with incomplete SCI could lead to improvements in gait ability, lower extremity muscle strength, balance, proprioception, and mobility. Additionally, end-effector RAGT could improve balance and gait abilities substantially better than CT.

Effects of body orientation and direction of movement on a knee joint angle reproduction test in healthy subjects: An experimental study

BACKGROUND

Joint position sense test assess patient mobility and proprioceptive ability. Yet, application used under different conditions may biases reproduction error resulting in different therapeutic consequences.

OBJECTIVE

To investigate knee angle reproduction test under different test conditions.

METHODS

25 healthy subjects (mean ± SD, age = 25 ± 2 years, activity level: 9 ± 2 training hours/week) performed knee angle reproduction test in the sitting and prone position, while changing the knee angle starting (i) from flexion and (ii) extension, (iii) inducing vibration on the semitendinosus tendon.

RESULTS

Absolute mean knee angle reproduction error showed significant difference for body position and vibration (Position: 95% CI 0.71 to 2.32; p< 0.001. No Vibration & Vibration: 95% CI -1.71 to -0.12; p= 0.027). Relative knee angle reproduction error was significant different in all conditions (No Vibration & Vibration: 95% CI -3.30 to -0.45; p= 0.010. Body orientation: 95% CI 1.08 to 3.93; p< 0.001. Direction of movement: 95% CI 0.56 to 3.41; p= 0.007).

CONCLUSION

Body orientation and movement direction influence the resulting knee angle reproduction error in healthy subjects. Practitioners are advised to use standardised test procedures when comparing different within- and between-patient results.

TRIAL REGISTRATION

DOI 10.17605/OSF.IO/AFWRP.

A scoping review of the different types of exercise programs proposed for the improvement of postural balance in adolescents with idiopathic scoliosis

BACKGROUND

Adolescent idiopathic scoliosis (AIS), which is the most common type of scoliosis, is a progressive disease that occurs in children aged 10-16 years. Abnormal curvature in AIS provokes spinal asymmetry of the upper body alignment and might deteriorate postural balancing and control ability.

OBJECTIVE

To evaluate the effect of exercise interventions on balance and postural stability in patients with adolescent idiopathic scoliosis.

METHODS

Embase, Scopus, Pubmed (Medline) and Web of Science databases were searched using the terms idiopathic scoliosis, physiotherapy, and balance. The articles selected were published in English in peer-reviewed journals from 2012 to July 2022.

RESULTS

Ten studies met the inclusion criteria. The PEDro scale values ranged from 2 to 6 (mean, 3.6), indicating a low level of scientific rigor. In the sample studies, spinal stabilization exercises were most often trialed (n= 3), followed by Schroth's exercise (n= 2), stretching and self-elongation exercise (n= 2), the exercise protocol of Blount and Moe, physiotherapeutic scoliosis-specific exercise, and proprioceptive neuromuscular facilitation exercise (all n= 1).

CONCLUSIONS

Physical therapists will be able to apply hippotherapy, Schroth exercise, physiotherapy scoliosis-specific exercise, trunk stabilization, proprioceptive neuromuscular facilitation exercise, spinal stabilization exercise, core stabilization exercise, and body awareness therapy to manage balance impairments in patients with adolescent idiopathic scoliosis, and further studies are needed to provide stronger evidence.

Plastic changes induced by muscle focal vibration: A possible mechanism for long-term motor improvements

Repetitive focal vibrations can induce positive and persistent after-effects. There is still no satisfactory interpretation of the underlying mechanisms. A rationale, which can provide consistency among different results, is highly desirable to guide both the use of the application and future research. To date, interpretive models are formulated to justify the results, depending on the specific protocol adopted. Indeed, protocol parameters, such as stimulus intensity and frequency, intervention time and administration period, are variable among different studies. However, in this article, we have identified features of the protocols that may allow us to suggest a possible common mechanism underlying the effectiveness of focal vibration under different physiologic and pathologic conditions. Since repetitive focal muscle vibration induces powerful and prolonged activation of muscle proprioceptors, we hypothesize that this intense activation generates adaptive synaptic changes along sensory and motor circuits. This may lead to long-term synaptic potentiation in the central network, inducing an enhancement of the learning capability. The plastic event could increase proprioceptive discriminative ability and accuracy of the spatial reference frame and, consequently, improve motor planning and execution for different motor functions and in the presence of different motor dysfunctions. The proposed mechanism may explain the surprising and sometimes particularly rapid improvements in motor execution in healthy and diseased individuals, regardless of specific physical training. This hypothetic mechanism may require experimental evidence and could lead to extend and adapt the application of the "learning without training" paradigms to other functional and recovery needs.

Altered Trunk Position Sense and Its Relationship With Spinal Posture and Spinal Mobility in Patients With Parkinson's Disease

INTRODUCTION

Proprioception is significantly affected by dysfunction of the basal ganglia, which play an important role in sensorimotor integration. Parkinson's disease (PD), which is characterized by progressive loss of the dopaminergic neurons of the substantia nigra, leads to a variety of motor and nonmotor symptoms throughout the course of the disease. The aim of this study was to determine trunk position sense and to investigate its relationship with spinal posture and spinal mobility in patients with PD.

METHODS

The study included 35 patients with PD and 35 age-matched control subjects. Trunk position sense was determined with "trunk reposition errors." A spinal mouse was used to assess spinal posture and spinal mobility.

RESULTS

According to the Hoehn-Yahr rating scale, the majority of the patients were in Stage 1 (68.6%). Trunk position sense was found to be significantly decreased in patients with PD compared with the control group (p < .001) but was not correlated with spinal posture and spinal mobility in patients with PD (p > .05).

CONCLUSIONS

This study revealed that trunk position sense was impaired in PD from the early stages of the disease. However, neither spinal posture nor spinal mobility was associated with decreased trunk proprioception. Further research into these relationships in the late stages of PD is needed.

Musculoskeletal disorders and functional characteristics of the neck and shoulder: Comparison between office workers using a laptop or desktop computer

BACKGROUND

Using a laptop for work is gaining rapid popularity, but there is little evidence of how it influences musculoskeletal disorders (MSDs) and functional characteristics of the neck and shoulder area.

OBJECTIVE

This study aimed to compare the prevalence of upper body MSDs and functional characteristics of the neck between office workers using a laptop or desktop computer.

METHODS

A total of 110 office workers with a mean age of 41±10 years participated. 45 office workers (73% female) used a laptop and 65 office workers (86% female) used desktop computers. The prevalence of MSDs was recorded using the Nordic Musculoskeletal Questionnaire. Active range of motion (AROM), maximal voluntary isometric contraction (MVC) force, joint position error (JPE), and pain-pressure threshold (PPT) of the neck and shoulder area were measured.

RESULTS

Laptop users experienced significantly more MSDs in the right shoulder area on the day of participation (p < 0.001, OR = 4.47), during the previous 7 days (p < 0.01, OR = 3.74), and at 6 months (p < 0.01, OR = 3.57). Laptop users also experienced significantly more MSDs in the left shoulder during the previous 7 days (p < 0.05, OR = 2.44). There were no statistically significant differences in any of the functional characteristics of the neck and shoulder area between the groups.

CONCLUSION

Using the laptop computer for office work may pose a higher risk of developing MSDs in the right shoulder area, but might not have long-term effects on the functional characteristics of the neck and shoulder area.

Upper Limb Function but Not Proprioception is Impaired in Essential Tremor: A Between-Groups Study and Causal Mediation Analysis

Background

Essential tremor (ET) is characterized by abnormal oscillatory muscle activity and cerebellar involvement, factors that can lead to proprioceptive deficits, especially in active tasks. The present study aimed to quantify the severity of proprioceptive deficits in people with ET and estimate how these contribute to functional impairments.

Methods

Upper limb sensory, proprioceptive and motor function was assessed inindividuals with ET (n = 20) and healthy individuals (n = 22). To measure proprioceptive ability, participants discriminated the width of grasped objects and the weight of objects liftedwith the wrist extensors. Causal mediation analysis was used to estimate the extentthat impairments in upper limb function in ET was mediated by proprioceptive ability.

Results

Participants with ET had impaired upper limb function in all outcomes, and had greater postural and kinetic tremor. There were no differences between groups in proprioceptive discrimination of width (between-group mean difference [95% CI]: 0.32 mm [-0.23 to 0.87 mm]) or weight (-1.12 g [-7.31 to 5.07 g]). Causal mediation analysis showed the effect of ET on upper limb function was not mediated by proprioceptive ability.

Conclusions

Upper limb function but not proprioception was impaired in ET. The effect of ET on motor function was not mediated by proprioception. These results indicate that the central nervous system of people with ET is able to accommodate mild to moderate tremor in active proprioceptive tasks that rely primarily on afferent signals from muscle spindles.

Molecular characterization of the intact mouse muscle spindle using a multi-omics approach

The proprioceptive system is essential for the control of coordinated movement, posture, and skeletal integrity. The sense of proprioception is produced in the brain using peripheral sensory input from receptors such as the muscle spindle, which detects changes in the length of skeletal muscles. Despite its importance, the molecular composition of the muscle spindle is largely unknown. In this study, we generated comprehensive transcriptomic and proteomic datasets of the entire muscle spindle isolated from the murine deep masseter muscle. We then associated differentially expressed genes with the various tissues composing the spindle using bioinformatic analysis. Immunostaining verified these predictions, thus establishing new markers for the different spindle tissues. Utilizing these markers, we identified the differentiation stages the spindle capsule cells undergo during development. Together, these findings provide comprehensive molecular characterization of the intact spindle as well as new tools to study its development and function in health and disease.

Development and validation of the multidimensional impacts of movement scale (MIMS) for yoga, weightlifting, and running

Background

Movement is an essential element in maintaining overall well-being, producing both physical and mental health benefits. Yoga is a mindful movement practice, with traditional yogic texts providing a framework, called the Koshas, that delineates how an intentional movement practice may impact multidimensional aspects of an individual. To date, no self-report measure examines the multifaceted ways that movement affects the individual at a physical and psychological level. Therefore, we developed the Multidimensional Impacts of Movement Scale (MIMS) by aligning ancient yogic traditions with current neuroscientific concepts.

Methods

MIMS was developed based on the five categories of the Koshas; 9 questions per Kosha resulted in 45 total questions. Participants (n = 103) self-identified as having yoga, running, or weightlifting as their primary movement practice, engaging in this practice at least 30 min per session, once a week, for the past 3 months. Participants engaged in their usual movement practice and then (within 2 h of their workout session) completed the MIMS along with a series of previously validated questionnaires. After a period of 2 weeks, participants completed their normal movement practice once again and took the MIMS a second time to assess test-retest reliability and Cronbach's alpha. Validity testing included convergent and divergent validity testing through Pearson's product-moment correlations and confirmatory factor analysis.

Results

One-hundred and three participants completed all study measures. Test-retest reliability demonstrated stability over time (r = 0.737, p < 0.001). Cronbach's alpha was between 0.775 and 0.840 for each of the factors, p < 0.001. MIMS was sensitive to confirmatory and discriminatory validity testing. Validity was also demonstrated through confirmatory factor analysis (i.e., Chi Square, Comparative Fit Index, Root Mean Square Error of Approximation).

Conclusion

MIMS is a valid and reliable tool to measure the multidimensional impacts of movement. The tool provides information about the effects of movement on a range of physical and psychological elements including subscales representing the body, energy, mind, intuition, and contentment. Physical activities that include aspects of mindfulness may demonstrate the most robust effects on the MIMS.

Brain motion networks predict head motion during rest- and task-fMRI

Introduction

The capacity to stay still during scanning, which is necessary to avoid motion confounds while imaging, varies markedly between people.

Methods

Here we investigated the effect of head motion on functional connectivity using connectome-based predictive modeling (CPM) and publicly available brain functional magnetic resonance imaging (fMRI) data from 414 individuals with low frame-to-frame motion (Δd < 0.18 mm). Leave-one-out was used for internal cross-validation of head motion prediction in 207 participants, and twofold cross-validation was used in an independent sample (n = 207).

Results and Discussion

Parametric testing, as well as CPM-based permutations for null hypothesis testing, revealed strong linear associations between observed and predicted values of head motion. Motion prediction accuracy was higher for task- than for rest-fMRI, and for absolute head motion (d) than for Δd. Denoising attenuated the predictability of head motion, but stricter framewise displacement threshold (FD = 0.2 mm) for motion censoring did not alter the accuracy of the predictions obtained with lenient censoring (FD = 0.5 mm). For rest-fMRI, prediction accuracy was lower for individuals with low motion (mean Δd < 0.02 mm; n = 200) than for those with moderate motion (Δd < 0.04 mm; n = 414). The cerebellum and default-mode network (DMN) regions that forecasted individual differences in d and Δd during six different tasks- and two rest-fMRI sessions were consistently prone to the deleterious effect of head motion. However, these findings generalized to a novel group of 1,422 individuals but not to simulated datasets without neurobiological contributions, suggesting that cerebellar and DMN connectivity could partially reflect functional signals pertaining to inhibitory motor control during fMRI.

The cross-cultural adaptation, validity, and reliability of the Spanish version of the Fremantle Back Awareness Questionnaire

Introduction

In chronic low back pain (CLBP), disturbed body image has been highlighted as a contributor to the condition and a potential target for treatment. The Fremantle Back Awareness Questionnaire (FreBAQ) allows its assessment. Following international guidelines for the cross-cultural translation of questionnaires, we aimed to translate the FreBAQ into Spanish (FreBAQ-S) and validate the new questionnaire in a sample of Spanish-speaking people with CLBP.

Methods

Two hundred and sixty-four adults with CLBP (91 males) and 128 healthy controls (34 males) completed an online form including the FreBAQ-S and questionnaires related to the pain experience. All participants were Spanish and no gender identities differing from biological sex were reported. A week later, 113 CLBP participants and 45 healthy controls (41 and 13 males, respectively), re-answered the FreBAQ-S to evaluate test-retest reliability. Confirmatory factor and multigroup analysis assessed the scale consistency on the patient sample. Discriminant and convergent validity were explored by between-group differences and the relationship with clinical characteristics. Reliability relied on Cronbach's alpha estimates and test-retest (intraclass correlation coefficient, standard error of measurement, minimal detectable change).

Results and discussion

Confirmatory factor analysis showed a one-factor structure of the questionnaire, without supporting evidence for item deletion (CFI = 0.97; TLI = 0.96; RMSEA = 0.06; SRMR = 0.07; SRMRu = 0.064). Multigroup analyses do not support mean invariance between groups regarding health condition or sex. The FreBAQ-S demonstrated good discriminant and convergent validity, internal consistency (α = 0.82), and test-retest reliability (ICC = 0.78; SE = 3.41; MDC = 5.12). The FreBAQ-S is a valid and reliable tool to assess back awareness in clinical and non-clinical samples.

Reliability and Validity of the Double Inclinometer Method for Assessing Thoracolumbar Joint Position Sense and Range of Movement in Patients with a Recent History of Low Back Pain

The study was aimed at examining the reliability of the Double Inclinometer (DI) method for the assessment of thoracolumbar Range of Movement (ROM) and Joint Position Sense (JPS) in patients with a recent history of Low Back Pain (LBP). Twenty patients with a history of LBP in the last three months participated. The thoracolumbar ROM and JPS were examined from a standing position by using both the DI and the tape measure method. The DI method was found to have moderate to good intra-rater (ICC = 0.68-0.79, SEM = 2.20-2.77°, SDD = 6.09-7.67°), moderate inter-rater (ICC = 0.59-0.62, SEM = 2.96-3.35°, SDD = 8.19-9.27°) and poor test-retest reliability (ICC = 0.13-0.17, SEM = 3.98-4.32°, SDD = 11.02-11.96°) for the assessment of thoracolumbar JPS. For the assessment of thoracolumbar ROM, the DI method was found to have good to excellent intra-rater (ICC = 0.88-0.94, SEM = 4.25-6.20°, SDD = 11.77-17.17°), excellent inter-rater (ICC = 0.90-0.91, SEM = 7.26-7.74°, SDD = 20.11-21.43°) and excellent test-retest reliability (ICC = 0.91-0.93, SEM = 6.03-6.87°, SDD = 16.70-19.02°). The concurrent validity of the DI method with the tape measure method was found to be very weak for the assessment of thoracolumbar JPS (r = 0.02, p = 0.93) and strong for the assessment of thoracolumbar ROM (r = 0.66, p = 0.001). The DI method seems to be a very reliable method for the assessment of thoracolumbar ROM in individuals with a recent history of LBP.

Investigating Wrist Joint Position Sense and Hand Functions in Children With Polyarticular Juvenile Idiopathic Arthritis With Wrist Involvement

Comparing the wrist joint position sense and hand functions between children with juvenile idiopathic arthritis (JIA) and healthy controls, and determining possible relationships between these parameters in children with JIA were the aims of this study. Twenty children with polyarticular JIA with wrist involvement (JIAWrist+), 20 children with other subtypes of JIA without wrist involvement (JIAWrist-), and 20 healthy controls were included. Wrist joint position sense was evaluated by measuring joint repositioning error. Hand functions were assessed by using the Purdue Pegboard test, hand grip strength, pinch strength, and Duruoz Hand Index. Joint position sense and hand functions were diminished in the JIAWrist+ group compared with healthy control group (P < .05). Few moderate relationships were detected between hand functions and wrist joint position sense (P < .05). Improving proprioceptive acuity by appropriate training methods may have a role in enhancing hand functions.

Wrist Proprioception in Adults with and without Subacute Stroke

Proprioception is critical to motor control and functional status but has received limited study early after stroke. Patients admitted to an inpatient rehabilitation facility for stroke (n = 18, mean(±SD) 12.5 ± 6.6 days from stroke) and older healthy controls (n = 19) completed the Wrist Position Sense Test (WPST), a validated, quantitative measure of wrist proprioception, as well as motor and cognitive testing. Patients were serially tested when available (n = 12, mean 11 days between assessments). In controls, mean(±SD) WPST error was 9.7 ± 3.5° in the dominant wrist and 8.8 ± 3.8° in the nondominant wrist (p = 0.31). In patients with stroke, WPST error was 18.6 ± 9° in the more-affected wrist, with abnormal values present in 88.2%; and 11.5 ± 5.6° in the less-affected wrist, with abnormal values present in 72.2%. Error in the more-affected wrist was higher than in the less-affected wrist (p = 0.003) or in the dominant (p = 0.001) and nondominant (p < 0.001) wrist of controls. Age and BBT performance correlated with dominant hand WPST error in controls. WPST error in either wrist after stroke was not related to age, BBT, MoCA, or Fugl-Meyer scores. WPST error did not significantly change in retested patients. Wrist proprioception deficits are common, bilateral, and persistent in subacute stroke and not explained by cognitive or motor deficits.

Relationship between proprioception and balance control among Chinese senior older adults

Background: Balance impairment is the most common risk factor for falls among older adults, with three potential factors (tactile sensation, proprioception, and muscle strength) being responsible for their balance control. However, controversies remain on whether or not balance control is related to the three contributors among older adults. Therefore, clarifying the above questions helps explain the mechanisms of increased falls among senior older adults. This study compares the balance control and the three factors and investigates their relationships among older adults of different ages. Methods: 166 participants ultimately passed the qualification assessment and were categorized into younger (YG, 60-69 years, n = 56), middle (MG, 70-79 years, n = 57), or older (OG, ≥80 years, n = 53) aged groups. Berg Balance Scale (BBS) performance, tactile sensation, proprioception, and muscle strength were tested. One-way ANOVA and partial correlation were performed to explore the differences between groups in BBS and its three potential contributors, along with the correlations between them within each age group. Results: Significant differences among the three groups were detected in BBS scores (p < 0.001), tactile sensation at the great toe (p = 0.015) and heel (p = 0.025), proprioception of knee flexion (p < 0.001) and extension (p < 0.001), and ankle plantarflexion (p < 0.001) and dorsiflexion (p < 0.001), and muscle strength of ankle plantarflexion (p < 0.001) and dorsiflexion (p < 0.001), and hip abduction (p < 0.001). Proprioception of knee flexion (r = -0.351, p = 0.009) and extension (r = -0.276, p = 0.041), and ankle plantarflexion (r = -0.283, p = 0.036), and muscle strength of ankle plantarflexion (r = 0.326, p = 0.015) and hip abduction (r = 0.415, p = 0.002) were correlated with BBS among the YG. Proprioception of ankle plantarflexion (r = -0.291, p = 0.030) and muscle strength of ankle plantarflexion (r = 0.448, p = 0.001) and dorsiflexion (r = 0.356, p = 0.007) were correlated with BBS among the MG. Muscle strength of ankle plantarflexion (r = 0.276, p = 0.039) and hip abduction (r = 0.324, p = 0.015) were correlated with BBS among the OG. Conclusion: YG and MG had better balance control, tactile sensation, proprioception, and muscle strength compared to OG. Proprioception correlated with balance control in YG and MG, but not in the OG. The worsen proprioception among the OG could be the key for increased falls. Exercise should be recommended to improve proprioception among senior older adults.

The consequence of head-loading on the neuro-musculoskeletal health of the ILembe District youth of KwaZulu-Natal

Background

Head-loading, as a mode of transporting food, water and firewood, is a longstanding tradition assigned to female South African youth and has been associated with adverse health consequences.

Objectives

This study determined the impact of head-loading on the neuromusculoskeletal health and proprioception of female South African youth.

Method

This study comprised a counterbalanced, within-subject, single-factor experimental design which compared the changes that occurred when the same independent variable (head-loading) within two homogenous groups was measured in terms of the dependent variables (outcomes: neuromusculoskeletal pain and proprioception) at two time periods, before and after the introduction of the independent variable. A cohort of South African female youth (n = 100), aged 9-17 years, voluntarily partook in the study. The participants were randomly distributed into an experimental (n = 50) and a control (n = 50) group. The experimental group stood in a head-loaded state with their respective habitual head-load mass. Their proprioception measurements were compared during their unloaded versus loaded states, with the proprioceptive measurements including the total proprioception index, the anterior-posterior (front-back) index and the medial-lateral (side-to-side) index. Participants furthermore completed a head-loading health-related questionnaire.

Results

Participants had a mean age of 12.3 ± 2.5 years, body mass of 44.4 ± 13.7 kg, stature of 145 ± 10 cm and a head-load mass of 8.0 ± 2.5 kg. Participants had poorer medial-lateral proprioception during head-loading as compared to their unloaded state (1.4 ± 0.8 as compared to 1.6 ± 0.9) (p < 0.05). Most youth (96%) experienced neuromusculoskeletal pain in their cervical vertebrae (40.9%), shoulders (27.3%), lumbar vertebrae (10.7%), arms (8.3%), legs (8.3%), knees (1.9%), fingers (1.5%), toes (0.5%) and thoracic vertebrae (0.5%) (χ²: p < 0.05).

Conclusion

Head-loading adversely affects the medial-lateral proprioception and neuromusculoskeletal health of participants.

Contribution

The findings of this study confirms that head-loading produces musculoskeletal pain.

Effects of traditional Chinese herb hot compress combined with therapeutic exercise on pain, proprioception, and functional performance among older adults with knee osteoarthritis: A randomized controlled trial

Background: Knee osteoarthritis (KOA) is one of the most common chronic progressive diseases with degenerative destruction of articular cartilage and bone, leading to knee pain, impaired proprioception, and reduced functional performance. This study was to investigate the effects of an 8-week Traditional Chinese herb hot compress (TCHHC) combined with therapeutic exercise (TE) on pain, proprioception, and functional performance among older adults with KOA. Methods: Twenty-seven older adults with KOA were recruited and randomly assigned to the TCHHC + TE or TE groups. Thirteen participants received TCHHC + TE, and fourteen received TE. At pre- (week 0) and post-intervention (week 9), their pain, joint proprioception, and functional performance were measured. Two-way ANOVA with repeated measures was adopted to analyze the data. Results: Compared with week 0, the pain score, proprioception thresholds of knee extension and ankle plantarflexion, and the times of TUG and 20-m walk tests decreased more significantly in the TCHHC + TE group than in the TE group at week 9. Conclusion: Compared with TE, the 8-week TCHHC + TE was superior in relieving pain, recovering proprioception, and improving functional performance among older adults with KOA. It is recommended that TCHHC should be adopted prior to TE to enhance the effects of KOA rehabilitation.

Beyond the Dorsal Column Medial Lemniscus in Proprioception and Stroke: A White Matter Investigation

Proprioceptive deficits are common following stroke, yet the white matter involved in proprioception is poorly understood. Evidence suggests that multiple cortical regions are involved in proprioception, each connected by major white matter tracts, namely: Superior Longitudinal Fasciculus (branches I, II and III), Arcuate Fasciculus and Middle Longitudinal Fasciculus (SLF I, SLF II, SLF III, AF and MdLF respectively). However, direct evidence on the involvement of these tracts in proprioception is lacking. Diffusion imaging was used to investigate the proprioceptive role of the SLF I, SLF II, SLF III, AF and MdLF in 26 participants with stroke, and seven control participants without stroke. Proprioception was assessed using a robotic Arm Position Matching (APM) task, performed in a Kinarm Exoskeleton robotic device. Lesions impacting each tract resulted in worse APM task performance. Lower Fractional Anisotropy (FA) was also associated with poorer APM task performance for the SLF II, III, AF and MdLF. Finally, connectivity data surrounding the cortical regions connected by each tract accurately predicted APM task impairments post-stroke. This study highlights the importance of major cortico-cortical white matter tracts, particularly the SLF III and AF, for accurate proprioception after stroke. It advances our understanding of the white matter tracts responsible for proprioception.

Factors associated with falls in patients with knee osteoarthritis: A cross-sectional study

Falls represent an important adverse effect associated with knee osteoarthritis and result in a significant financial burden on the healthcare system. Therefore, identification of fall predictors is essential to minimize fall incidence. However, few studies have investigated falls and fall predictors, particularly focused on the fear of falls and proprioception. In this study, we investigated significant fall predictors in patients with knee osteoarthritis in Malang, Indonesia. Our findings may serve as useful guidelines to develop geriatric fall prevention programs. This cross-sectional survey using purposive sampling was performed between April and July 2021 and included 372 participants. We recorded the following data: sociodemographic and medical history questionnaire responses, visual analog scale scores, Hopkins falls grading scale scores, Fall Efficacy Scale-International scores, proprioception test findings, knee injury and osteoarthritis outcome score (KOOS), range of motion (ROM), chair stand test and the timed up and go test performance. Data were analyzed using the chi-square and t tests, and multivariate logistic regression to determine significant fall predictors. Multivariate logistic regression analysis showed a lower risk of falls in patients with better proprioception and ROM than in the other groups (odds ratio 0.55 vs 0.96). The risk of falls was higher in patients with higher KOOS symptoms, fear of falls, diagnosis of low back pain and diabetes mellitus, and increased body mass index than in the other groups (odds ratio 1.41, 2.65, 1.27, 3.45, and 1.10, respectively. Our study shows that knee proprioception and ROM serve as protective factors against falls, whereas KOOS symptoms, fear of falls, low back pain, diabetes mellitus, and body mass index were associated with a high risk of falls, with diabetes mellitus and fear of falls being the most significant risk factors. These findings may be useful to policy makers to develop a fall prevention program that can be implemented in community health care centers across Indonesia to deliver individualized, person-centered care and improve fall prevention strategies through a systematic process comprising evaluation, intervention, and monitoring to minimize fall risk.

Assessment of grip force sense test-retest reliability in healthy male participants

There has been a lack of research to date regarding the test-retest reliability of grip force sense in healthy adult males. This study was therefore designed to explore this topic across a series of target force levels using an ipsilateral force reproduction task. The same experienced research staff conducted two testing sessions for each study participant, with 1 week between test sessions. Intraclass correlation coefficient values indicated that these force sensing tests exhibited good to fair reliability with respect to both absolute error (0.42-0.63) and constant error (0.49-0.60), although variable error was indicative of poor reliability (-0.85 to 0.14). Together, these results suggest that researchers can achieve a fair level of test-retest reliability when analysing grip force sense in healthy adult males, with results being most reliable at force levels of 20 N and 50 N, as determined based upon measured constant error and absolute error. Practitioner summary: To ensure that grip force sense can be accurately interpreted over time, it is important to assess the test-retest reliability. It is recommended that practitioners measure the absolute error and constant error at force levels of 20 N and 50 N when assessing grip force sense in a clinical setting.

Can a structural leg length discrepancy contribute to persistent concussion symptoms? A case report

In the past several years, concussions and post-concussion syndrome (PCS) have become more commonly recognized conditions. However, with limited physiological explanation for post-concussion syndrome, there is also limited evidence supporting effective treatment. The vestibular system plays a role in postural reflexes and coordinated eye and cervical spine movements and is often disrupted in patients with prolonged concussion symptoms. This disruption has contributed to some of the most debilitating symptoms in PCS patients including dizziness, nausea, and balance deficits. Ongoing, post-concussion, vestibulo-ocular/cervical-ocular disruption due to an underlying structural leg length discrepancy as a contributing factor has not been previously described in the literature. A case of PCS with initial conservative treatment of their structural leg length discrepancy and subsequent vestibulo-ocular/cervical-ocular rehabilitation is presented.

The brain integrates proprioceptive information to ensure robust locomotion

Robust locomotion relies on information from proprioceptors: sensory organs that communicate the position of body parts to the spinal cord and brain. Proprioceptive circuits in the spinal cord are known to coarsely regulate locomotion in the presence of perturbations. Yet, the regulatory importance of the brain in maintaining robust locomotion remains less clear. Here, through mouse genetic studies and in vivo electrophysiology, we examined the role of the brain in integrating proprioceptive information during perturbed locomotion. The systemic removal of proprioceptors left the mice in a constantly perturbed state, similar to that observed during mechanically perturbed locomotion in wild-type mice and characterised by longer and less accurate synergistic activation patterns. By contrast, after surgically interrupting the ascending proprioceptive projection to the brain through the dorsal column of the spinal cord, wild-type mice showed normal walking behaviour, yet lost the ability to respond to external perturbations. Our findings provide direct evidence of a pivotal role for ascending proprioceptive information in achieving robust, safe locomotion. KEY POINTS: Whether brain integration of proprioceptive feedback is crucial for coping with perturbed locomotion is not clear. We showed a crucial role of the brain for responding to external perturbations and ensure robust locomotion. We used mouse genetics to remove proprioceptors and a spinal lesion model to interrupt the flow of proprioceptive information to the brain through the dorsal column in wild-type animals. Using a custom-built treadmill, we administered sudden and random mechanical perturbations to mice during walking. External perturbations affected locomotion in wild-type mice similar to the absence of proprioceptors in genetically modified mice. Proprioceptive feedback from muscle spindles and Golgi tendon organs contributed to locomotor robustness. Wild-type mice lost the ability to respond to external perturbations after interruption of the ascending proprioceptive projection to the brainstem.

Development and pilot testing of an early childhood somatosensory assessment: Somatosensory test of reaching

Thirty-two children (50% female, 59.3% White, 7-60 months), from middle to high socioeconomic status families, participated in pilot feasibility and validity testing of the somatosensory test of reaching (STOR). STOR tested the child's accuracy of reach to visual and somatosensory targets. All children were able to complete the assessment. Statistically significant differences were found between age groups (p = .0001), showing developmental trends, and between test conditions (p < .001), showing that the ability to reach to visible targets develops before somatosensory targets. STOR also showed a moderate correlation with the Developmental Assessment of Young Children 2nd edition. STOR appears to be a promising tool for assessing somatosensory processing in very young children, and it warrants additional testing in larger participant samples.

Reduced feedback barely slows down proprioceptive recalibration

Introducing altered visual feedback of the hand produces quick adaptation of reaching movements. Our lab has shown that the associated shifts in estimates of the felt position of the hand saturate within a few training trials. The current study investigates whether the rapid changes in felt hand position that occur during classic visuomotor adaptation are diminished or slowed when training feedback is reduced. We reduced feedback by either providing visual feedback only at the end of the reach (terminal feedback) or constraining hand movements to reduce motor adaptation-related error signals such as sensory prediction errors and task errors (exposure). We measured changes as participants completed reaches with a 30° rotation, a -30° rotation, and clamped visual feedback, with these two "impoverished" training conditions, along with classic visuomotor adaptation training, while continuously estimating their felt hand position. Training with terminal feedback slightly reduced the initial rate of change in overall adaptation. However, the rate of change in hand localization, as well as the asymptote of hand localization shifts in both the terminal feedback group and the exposure training group was not noticeably different from those in the classic training group. Taken together, shifts in felt hand position are rapid and robust responses to sensory mismatches and are at best slightly modulated when feedback is reduced. This suggests that given the speed and invariance to the quality of feedback of proprioceptive recalibration, it could immediately contribute to all kinds of reach adaptation.NEW & NOTEWORTHY Reaching to targets with altered visual feedback about hand position leads to adaptation of movements as well as shifts in estimates of felt hand position. Felt hand position can shift in as little as one trial, and here we show that there is no noticeable reduction in speed when the feedback about movements is impoverished, indicating the robustness of the process of recalibrating felt hand position.

From Virtual Reality to Regenerative Virtual Therapy: Some Insights from a Systematic Review Exploring Inner Body Perception in Anorexia and Bulimia Nervosa

Despite advances in our understanding of the behavioral and molecular factors that underlie the onset and maintenance of Eating Disorders (EDs), it is still necessary to optimize treatment strategies and establish their efficacy. In this context, over the past 25 years, Virtual Reality (VR) has provided creative treatments for a variety of ED symptoms, including body dissatisfaction, craving, and negative emotions. Recently, different researchers suggested that EDs may reflect a broader impairment in multisensory body integration, and a particular VR technique-VR body swapping-has been used to repair it, but with limited clinical results. In this paper, we use the results of a systematic review employing PRISMA guidelines that explore inner body perception in EDs (21 studies included), with the ultimate goal to analyze the features of multisensory impairment associated with this clinical condition and provide possible solutions. Deficits in interoception, proprioception, and vestibular signals were observed across Anorexia and Bulimia Nervosa, suggesting that: (a) alteration of inner body perception might be a crucial feature of EDs, even if further research is needed and; (b) VR, to be effective with these patients, has to simulate/modify both the external and the internal body. Following this outcome, we introduce a new therapeutic approach-Regenerative Virtual Therapy-that integrates VR with different technologies and clinical strategies to regenerate a faulty bodily experience by stimulating the multisensory brain mechanisms and promoting self-regenerative processes within the brain itself.

Single-textured insole for the less affected leg in freezing of gait: A hypothesis

Freezing of gait (FoG) is one of the most widely distributed and disabling gait phenomena in people with Parkinson's disease (PD). The current therapeutic interventions show suboptimal efficacy in FoG. Lower extremity proprioception impairments, especially in the most affected leg, gait initiation hesitation, and gait asymmetry are FoG factors, and there is a need to accurately consider them in terms of therapeutic approaches. Accordingly, we hypothesize that using a single-textured insole for the less affected leg may improve FoG by providing proprioceptive stimulation that enhances sensory processing and reduces gait hesitation and asymmetry. Proprioceptive sensory stimulation for the less affected limb could be more effective than for the double legs that are currently used in rehabilitation settings due to the sensory processing in the less affected basal ganglia being better.

Effect of Different Landing Heights and Loads on Ankle Inversion Proprioception during Landing in Individuals with and without Chronic Ankle Instability

Proprioception is essential for neuromuscular control in relation to sport injury and performance. The effect of landing heights and loads on ankle inversion proprioceptive performance in individuals with or without chronic ankle instability (CAI) may be important but are still unclear. Forty-three participants (21 CAI and 22 non-CAI) volunteered for this study. The Ankle Inversion Discrimination Apparatus for Landing (AIDAL), with one foot landing on a horizontal surface and the test foot landing on an angled surface (10°, 12°, 14°, 16°), was utilized to assess ankle proprioception during landing. All participants performed the task from a landing height of 10 cm and 20 cm with 100% and 110% body weight loading. The four testing conditions were randomized. A repeated measures ANOVA was used for data analysis. The result showed that individuals with CAI performed significantly worse across the four testing conditions (p = 0.018). In addition, an increased landing height (p = 0.010), not loading (p > 0.05), significantly impaired ankle inversion discrimination sensitivity. In conclusion, compared to non-CAI, individuals with CAI showed significantly worse ankle inversion proprioceptive performance during landing. An increased landing height, not loading, resulted in decreased ankle proprioceptive sensitivity. These findings suggest that landing from a higher platform may increase the uncertainty of judging ankle positions in space, which may increase the risk of ankle injury.

A Reliability of Active and Passive Knee Joint Position Sense Assessment Using the Luna EMG Rehabilitation Robot

Joint position sense (JPS) is the awareness of joint location in space, indicating accuracy and precision of the movement. Therefore, the aim of the present study is to determine the reliability of active and passive JPS assessment regarding the knee joint. This was carried out using the Luna EMG rehabilitation robot. Further analysis assessed whether the examination of only the dominant site is justified and if there are differences between sites. The study comprised 24 healthy male participants aged 24.13 ± 2.82 years, performing sports at a recreational level. Using the Luna EMG rehabilitation robot, JPS tests were performed for the right and left knees during flexion and extension in active and passive mode, in two separate sessions with a 1-week interval. Both knee flexion and extension in active and passive modes demonstrated high reliability (ICC = 0.866-0.982; SEM = 0.63-0.31). The mean JPS angle error did not differ significantly between the right and left lower limbs (p < 0.05); however, no between-limb correlation was noted (r = 0.21-0.34; p > 0.05). The Bland-Altman plots showed that the between-limb bias was minimal, with relatively wide limits of agreement. Therefore, it was concluded that the Luna EMG rehabilitation robot is a reliable tool for active and passive knee JPS assessment. In our study, JPS angle error did not differ significantly between left and right sides; however, the slight asymmetry was observed (visible in broad level of agreement exceeding 5° in Bland-Altman plots), what may suggest that in healthy subjects, e.g., active athletes, proprioception should always be assessed on both sides.

Functional and biochemical improvement following total knee arthroplasty in early postoperative period

OBJECTIVE

There are very few studies about total knee arthroplasty biomechanical and biochemical effects in the early postoperative period. The aim of this study was to investigate the effect of total knee arthroplasty on pain intensity, knee joint valgus angle, malalignment, functional status, knee joint position sense, and cytokine levels.

METHODS

A total of 29 patients (female/male: 24/5) who underwent total knee arthroplasty were included in the late-stage knee osteoarthritis group, and 22 patients (female/male: 13/9) with grade 4 osteoarthritis were included in the early-stage knee osteoarthritis group. The visual analog scale and the Western Ontario and McMaster Universities Osteoarthritis Index were used to evaluate the pain intensity and functional status. Alignment and knee position sense measurements were also calculated. Systemic venous blood samples were taken to evaluate the interleukin-6, tumor necrosis factor-alpha, and interleukin-1 beta cytokine levels.

RESULTS

In the study group, there were positive improvements in pain intensity, functional status, valgus angle, malalignment, amount of joint position sense deviation at 70° knee flexion angle parameters, and interleukin-6 of patients at the postoperative 6th week compared to the preoperative period (p<0.05). The patients in the study group had similar or better results in pain intensity, functional status, valgus angle, malalignment, amount of joint position sense deviation at 35°, 55°, and 70° knee flexion angles parameters, and in interleukin-6, compared to the control group at postoperative 6th week.

CONCLUSION

Total knee arthroplasty provides improvements in pain, function, valgus angle, joint position sense, and interleukin-6 in the early postoperative period.

An Investigation into the Effects of Changing Dorso-Plantar Hoof Balance on Equine Hind Limb Posture

Links between poor hind hoof balance, pathologies in the hind limb and associated altered posture have been suggested but not quantified. The hoof is proposed as a neuro-sensory organ responsible for informing equine stance with implications for musculoskeletal health in the hind limb and trunk of the horse. This study aims to quantify equine limb posture and its relationship with hoof balance. Twelve horses presenting with negative plantar angles were photographed and limb posture documented before and after the creation of positive plantar angles and improved three-dimensional proportions around the centre of rotation of the distal-interphalangeal joint, using farriery prosthetics. The results showed that horses presenting with negative plantar angles had canted-in postures and that farriery intervention had a significant effect on hind limb orientation in seven of these horses. There was a significant difference in metatarsal angle pre and post intervention with the mean for pre intervention being 81.3° ± 5.1 and post intervention being 88.0° ± 3.8 in the right hind and 74.4° ± 3.7 and 87.1° ± 2.9 in the left hind. The findings of this study support the hypothesis that the hoof balance informs equine stance and can play a role in affecting limb posture.

Mechanosensory encoding dysfunction emerges from cancer-chemotherapy interaction

Persistent sensory, motor and cognitive disabilities comprise chemotherapy-induced neural disorders (CIND) that limit quality of life with little therapeutic relief for cancer survivors. Our recent preclinical study provides new insight into a condition impacting the severity of chronic CIND. We find that sensorimotor disability observed following cancer treatment exceeds that attributable to chemotherapy alone. A possible explanation for intensified disability emerged from evidence that codependent effects of cancer and chemotherapy amplify defective firing in primary sensory neurons supplying one type of low threshold mechanosensory receptor (LTMR). Here we test whether cancer's modification of chemotherapy-induced sensory defects generalizes across eight LTMR submodalities that collectively generate the signals of origin for proprioceptive and tactile perception and guidance of body movement. Preclinical study enabled controlled comparison of the independent contributions of chemotherapy and cancer to their clinically relevant combined effects. We compared data sampled from rats that were otherwise healthy or bearing colon cancer and treated, or not, with human-scaled, standard-of-care chemotherapy with oxaliplatin. Action potential firing patterns encoding naturalistic mechanical perturbations of skeletal muscle and skin were measured electrophysiologically in vivo from multiple types of LTMR neurons. All expressed aberrant encoding of dynamic and/or static features of mechanical stimuli in healthy rats treated with chemotherapy, and surprisingly also by some LTMRs in cancer-bearing rats that were not treated. By comparison, chemotherapy and cancer in combination worsened encoding aberrations, especially in slowly adapting LTMRs supplying both muscle and glabrous skin. Probabilistic modeling best predicted observed encoding defects when incorporating interaction effects of cancer and chemotherapy. We conclude that for multiple mechanosensory submodalities, the severity of encoding defects is modulated by a codependence of chemotherapy side effects and cancer's systemic processes. We propose that the severity of CIND might be reduced by therapeutically targeting the mechanisms, yet to be determined, by which cancer magnifies chemotherapy's neural side effects as an alternative to reducing chemotherapy and its life-saving benefits.

Comparisons and Associations between Hip-Joint Position Sense and Glycosylated Hemoglobin in Elderly Subjects with Type 2 Diabetes Mellitus-A Cross-Sectional Study

Hip-joint position sense (JPS) accuracy may be impaired in individuals with type 2 diabetes mellitus (T2DM). An impaired hip JPS can alter postural control and bodily balance. The objectives of this study are to (1) compare the hip JPS between T2DM and asymptomatic and (2) assess the relationship between hip JPS and glycosylated hemoglobin (HbAlc). This comparative cross-sectional study included 117 elderly individuals with T2DM (mean age: 59.82 ± 6.80 y) and 142 who were asymptomatic (mean age: 57.52 ± 6.90 y). The hip JPS was measured using a digital inclinometer. The individuals were repositioned to a target position with their eyes closed, and the magnitudes of matching errors were estimated as reposition errors. The hip JPS was evaluated in the flexion and abduction directions. The magnitude of reposition errors was significantly larger in the T2DM group in the right flexion (p < 0.001), the right abduction (p < 0.001), the left flexion (p < 0.001), and the left abduction (p < 0.001) directions compared to the asymptomatic group. HbA1c values showed a significant positive correlation with JPS in the right-hip flexion (r = 0.43, p < 0.001), the right-hip abduction (r = 0.36, p < 0.001), the left-hip flexion (r = 0.44, p < 0.001), and the left-hip abduction (r = 0.49, p < 0.001) directions. Hip JPS testing may be considered when assessing and formulating treatment strategies for individuals with type 2 diabetes. Future research should focus on how hip JPS can impact balance and falls in individuals with T2DM.

Effect of stabilization exercise combined with respiratory resistance and whole body vibration on patients with lumbar instability: A randomized controlled trial

BACKGROUND

Lumbar stability exercise promotes deep muscle functions, and it is an effective intervention method for increasing proprioceptive sensation. This study aims to explore and compare the effects of lumbar stability exercise with respiratory resistance and whole body vibration on patients with lumbar instability.

METHODS

This study is a 3-group randomized control trial. Through screening tests, 48 patients with lumbar instability were selected and randomly assigned to SE group (n = 16), stabilization exercise program using respiratory resistance (SER) group (n = 16), and stabilization exercise program using respiratory resistance and whole body vibration (SERW) group (n = 16). In order to compare the effects depending on the intervention methods, quadruple visual analogue scale (QVAS), Functional Ability Roland-Morris low back pain and disability questionnaire ([RMDQ], center of pressure path length, velocity, and area), Korean version of fear-avoidance beliefs questionnaire, and Pulmonary Function were used for measurement.

RESULTS

All of the groups showed significant improvements in QVAS, RMDQ, Korean version of fear-avoidance beliefs questionnaire, and balance abilities before and after the interventions. The SER group and SERW group showed a significant difference in QVAS and RMDQ than the SE group (P < .05). In addition, balance ability showed a significant difference in SERW group (P < .05), where only the SER group showed a significant difference in pulmonary function indexes including forced vital capacity, forced expiratory volume in 1 second, maximum inspiratory pressure, and maximum expiratory pressure (P < .05).

CONCLUSION

Stabilization exercise program using respiratory resistance and whole-body vibration administered according to the purpose of intervention methods may be effective exercise programs for people with lumbar instability.

Identifying Body Awareness-Related Brain Network Changes After Cognitive Multisensory Rehabilitation for Neuropathic Pain Relief in Adults With Spinal Cord Injury: Protocol of a Phase I Randomized Controlled Trial

Background

About 69% of the 299,000 Americans living with spinal cord injury (SCI) experience long-term debilitating neuropathic pain. New treatments are needed because current treatments do not provide enough pain relief. We have found that insular-opercular brain network alterations may contribute to neuropathic pain and that restoring this network could reduce neuropathic pain. Here, we outline a study protocol using a physical therapy approach, cognitive multisensory rehabilitation (CMR), which has been shown to restore OP1/OP4 connections in adults post stroke, to test our hypothesis that CMR can normalize pain perception through restoring OP1/OP4 connectivity in adults with SCI and relieve neuropathic pain.

Objectives

To compare baseline brain function via resting-state and task-based functional magnetic resonance imaging in adults with SCI versus uninjured controls, and to identify changes in brain function and behavioral pain outcomes after CMR in adults with SCI.

Methods

In this phase I randomized controlled trial, adults with SCI will be randomized into two groups: Group A will receive 6 weeks of CMR followed by 6 weeks of standard of care (no therapy) at home. Group B will start with 6 weeks of standard of care (no therapy) at home and then receive 6 weeks of CMR. Neuroimaging and behavioral measures are collected at baseline, after the first 6 weeks (A: post therapy, B: post waitlist), and after the second 6 weeks (A: post-therapy follow-up, B: post therapy), with follow-up of both groups up to 12 months.

Conclusion

The successful outcome of our study will be a critical next step toward implementing CMR in clinical care to improve health in adults with SCI.

Neck Muscle Vibration Alters Upper Limb Proprioception as Demonstrated by Changes in Accuracy and Precision during an Elbow Repositioning Task

Upper limb control depends on accurate internal models of limb position relative to the head and neck, accurate sensory inputs, and accurate cortical processing. Transient alterations in neck afferent feedback induced by muscle vibration may impact upper limb proprioception. This research aimed to determine the effects of neck muscle vibration on upper limb proprioception using a novel elbow repositioning task (ERT). 26 right-handed participants aged 22.21 ± 2.64 performed the ERT consisting of three target angles between 80−90° (T1), 90−100° (T2) and 100−110° (T3). Controls (CONT) (n = 13, 6F) received 10 min of rest and the vibration group (VIB) (n = 13, 6F) received 10 min of 60 Hz vibration over the right sternocleidomastoid and left cervical extensor muscles. Task performance was reassessed following experimental manipulation. Significant time by group interactions occurred for T1: (F1,24 = 25.330, p < 0.001, ηp2 = 0.513) where CONT improved by 26.08% and VIB worsened by 134.27%, T2: (F1,24 = 16.157, p < 0.001, ηp2 = 0.402) where CONT improved by 20.39% and VIB worsened by 109.54%, and T3: (F1,24 = 21.923, p < 0.001, ηp2 = 0.447) where CONT improved by 37.11% and VIB worsened by 54.39%. Improvements in repositioning accuracy indicates improved proprioceptive ability with practice in controls. Decreased accuracy following vibration suggests that vibration altered proprioceptive inputs used to construct body schema, leading to inaccurate joint position sense and the observed changes in elbow repositioning accuracy.

Cervical Joint Position Sense and Its Correlations with Postural Stability in Subjects with Fibromyalgia Syndrome

Cervical joint position sense (JPS) and postural stability are vital to maintaining balance and preventing falls in fibromyalgia syndrome (FMS). Impaired cervical JPS may influence postural stability, and understanding the relationship between them can aid in formulating treatment strategies in individuals with FMS. This study aims to (1) assess cervical JPS and postural stability between FMS and control group and (2) determine the correlation between cervical JPS and postural stability in the FMS group. This cross-sectional study recruited 92 FMS patients (mean age: 51.52 ± 7.7 yrs.) and 92 healthy controls (mean age: 49.36 ± 6.9 yrs.). A cervical range of motion (CROM) unit was utilized to assess cervical JPS. The postural stability was assessed using an IsoFree force platform, and anterior-posterior (A/P) and medial-lateral (M/L) directions of sway and ellipse area were measured. Cervical JPS and postural stability tests were assessed and compared between FMS and control groups. Cervical JPS was significantly impaired in FMS compared to the control group (p < 0.001). The JPS errors in FMS group were larger in flexion (FMS = 5.5°, control = 2.4°), extension (FMS = 6.4°, control = 3.0°), and rotation in left (FMS = 5.4°, control = 2.2°) and right directions (FMS = 5.1°, control = 2.8°). FMS individuals demonstrated statistically significant impaired postural stability compared to control in both the dominant and non-dominant legs tested (p < 0.001). The cervical JPS test showed moderate to strong positive correlations with postural stability variables. Statistically significant correlations were observed in all the JPS directions tested with all the postural stability variables (A/P and M/L sway and ellipse area). The correlation coefficients ranged between r = 0.37 (moderate) to 0.75 (strong). Cervical JPS and postural stability are impaired in FMS individuals. A moderate to strong relationship existed between JPS and postural stability. Individuals with FMS who had a greater magnitude of cervical JPS errors exhibited more severe postural control deficits. Therefore, cervical JPS and postural stability tests should be incorporated into routine clinical practice when assessing or formulating treatment strategies for patients with FMS.

Posture dependent factors influence movement variability when reaching to nearby virtual objects

Reaching movements are subject to noise arising during the sensing, planning and execution phases of movement production, which contributes to movement variability. When vision of the moving hand is available, reach endpoint variability appears to be strongly influenced by internal noise associated with the specification and/or online updating of movement plans in visual coordinates. In contrast, without hand vision, endpoint variability appears more dependent upon movement direction, suggesting a greater influence of execution noise. Given that execution noise acts in part at the muscular level, we hypothesized that reaching variability should depend not only on movement direction but initial arm posture as well. Moreover, given that the effects of execution noise are more apparent when hand vision is unavailable, we reasoned that postural effects would be more evident when visual feedback was withheld. To test these hypotheses, participants planned memory-guided reaching movements to three frontal plane targets using one of two initial arm postures ("adducted" or "abducted"), attained by rotating the arm about the shoulder-hand axis. In this way, variability was examined for two sets of movements that were largely identical in endpoint coordinates but different in joint/muscle-based coordinates. We found that patterns of reaching variability differed in several respects when movements were initiated with different arm postures. These postural effects were evident shortly after movement onset, near the midpoints of the movements, and again at the endpoints. At the endpoints, posture dependent effects interacted with effects of visual feedback to determine some aspects of variability. These results suggest that posture dependent execution noise interacts with feedback control mechanisms and biomechanical factors to determine patterns of reach endpoint variability in 3D space.

Factors Influencing Treatment Outcome and Proprioception after Electrocoagulation of the Femoral Insertion of the Anterior Cruciate Ligament

(1) Background: Studies have established that exercises shaping the sense of deep sensation are an important element of medical rehabilitation of patients after vaporization of the femoral insertion of the anterior cruciate ligament and affect the restoration of correct movement patterns, thus reducing the risk of injuries. The aim of this study was to determine the factors influencing the treatment outcome and deep-feeling function after applying a specific rehabilitation scheme 12 weeks after anterior cruciate ligament electrocoagulation surgery. (2) Methods: The study group consisted of 41 patients after partial rupture of the anterior cruciate ligament, who underwent electrocoagulation of the femoral cruciate ligament attachment and microfracture of the femoral attachment area. All patients were operated on by the same surgeon and then rehabilitated according to the same medical rehabilitation protocol. The anthropometric and clinical data were collected through an anterior drawer test, Lachman test, assessment of the range of movements in the knee joint, muscle strength test, Unterberger test and Lysholm questionnaire. The assessment was performed before the surgery, and then on days 7-10, after 6 and 12 weeks of rehabilitation treatment. (3) Results: Statistical improvement of the parameters was demonstrated by strength of the quadriceps and hamstrings muscle, the Unterberger test, and the Lysholm scale after surgery. A negative correlation was found between the Unterberger test and Lysholm scale at the end of the research period and it differed depending on the gender and the dominant limb. The Lysholm scale and muscle strength were independent of sex, dominant extremity and associated damage of the meniscus and cartilage. The Lysholm scale 6 weeks after surgery negatively correlated with BMI. (4) Conclusions: Stability of the knee joint and improvement of proprioception were demonstrated 12 weeks after treatment with an ACL electrocoagulation and rehabilitation regimen. The factors contributing to a better treatment outcome were greater muscle strength, less thigh asymmetry, better sense of depth, younger age and lower body weight.

Typical Development of Finger Position Sense From Late Childhood to Adolescence

Finger position sense is a proprioceptive modality highly important for fine motor control. Its developmental time course is largely unknown. This cross-sectional study examined its typical development in 138 children (8-17 years) and a group of 14 healthy young adults using a fast and novel psychophysical test that yielded objective measures of position sense acuity. Participants placed their hands underneath a computer tablet and judged the perceived position of their unseen index finger relative to two visible areas displayed on a tablet following a two-forced-choice paradigm. Responses were fitted to a psychometric acuity function from which the difference between the point-of-subjective-equality and the veridical finger position (ΔPSE) was derived as a measure of position sense bias, and the uncertainty area (UA) as a measure of precision. The main results are: First, children under 12 exhibited a significantly greater UA than adults while adolescent children (13-17 years) exhibited no significant differences when compared to adults. Second, no significant age-related differences in ΔPSE were found across the age range of 8-17 years. This implies that the typical development of finger position sense from late childhood to adulthood is characterized as an age-dependent increase in proprioceptive precision and not as a decrease in bias.

Encoding type, medication, and deep brain stimulation differentially affect memory-guided sequential reaching movements in Parkinson's disease

Memory-guided movements, vital to daily activities, are especially impaired in Parkinson's disease (PD). However, studies examining the effects of how information is encoded in memory and the effects of common treatments of PD, such as medication and subthalamic nucleus deep brain stimulation (STN-DBS), on memory-guided movements are uncommon and their findings are equivocal. We designed two memory-guided sequential reaching tasks, peripheral-vision or proprioception encoded, to investigate the effects of encoding type (peripheral-vision vs. proprioception), medication (on- vs. off-), STN-DBS (on- vs. off-, while off-medication), and compared STN-DBS vs. medication on reaching amplitude, error, and velocity. We collected data from 16 (analyzed n = 7) participants with PD, pre- and post-STN-DBS surgery, and 17 (analyzed n = 14) healthy controls. We had four important findings. First, encoding type differentially affected reaching performance: peripheral-vision reaches were faster and more accurate. Also, encoding type differentially affected reaching deficits in PD compared to healthy controls: peripheral-vision reaches manifested larger deficits in amplitude. Second, the effect of medication depended on encoding type: medication had no effect on amplitude, but reduced error for both encoding types, and increased velocity only during peripheral-vision encoding. Third, the effect of STN-DBS depended on encoding type: STN-DBS increased amplitude for both encoding types, increased error during proprioception encoding, and increased velocity for both encoding types. Fourth, STN-DBS was superior to medication with respect to increasing amplitude and velocity, whereas medication was superior to STN-DBS with respect to reducing error. We discuss our findings in the context of the previous literature and consider mechanisms for the differential effects of medication and STN-DBS.

Timely Revisit of Proprioceptive Deficits in Adolescent Idiopathic Scoliosis: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

The present review aimed to summarize the evidence regarding differences in proprioception between children with and without adolescent idiopathic scoliosis (AIS).

METHODS

Seven electronic databases were searched from their inception to April 10, 2021. Articles were included if they involved: (1) AIS patients aged between 10 and 18 years, (2) measurements of proprioceptive abilities, and (3) comparisons with non-AIS controls. Animal studies, case reports, commentaries, conference proceedings, research protocols, and reviews were excluded. Two reviewers independently conducted literature screening, data extraction, risks of bias assessments, and quality of evidence evaluations. Relevant information was pooled for meta-analyses.

RESULTS

From 432 identified citations, 11 case-control studies comprising 1121 participants were included. The meta-analyses showed that AIS participants displayed proprioceptive deficits as compared to non-AIS controls. Moderate evidence supported that AIS participants showed significantly larger repositioning errors than healthy controls (pooled mean difference = 1.27 degrees, P < .01). Low evidence substantiated that AIS participants had significantly greater motion detection threshold (pooled mean difference = 1.60 degrees, P < .01) and abnormal somatosensory evoked potentials (pooled mean difference = .36 milliseconds, P = .01) than non-AIS counterparts.

CONCLUSIONS

Consistent findings revealed that proprioceptive deficits occurred in AIS patients. Further investigations on the causal relationship between AIS and proprioception, and the identification of the subgroup of AIS patients with proprioceptive deficit are needed.

Prospective comparative study between knee alignment-oriented static and dynamic balance exercise in patellofemoral pain syndrome patients with dynamic knee valgus

Exercise therapy has been reported as an effective treatment method for patellofemoral pain syndrome (PFPS). However, there is a lack of studies regarding the effectiveness of balance exercise in the treatment of patients with PFPS. This study aimed to prospectively compare changes in proprioception, neuromuscular control, knee muscle strength, and patient-reported outcomes between patients with PFPS treated with knee alignment-oriented static balance exercise (SBE) and dynamic balance exercise (DBE). The participants were divided into 2 groups: 17 knee alignment-oriented SBE group and 19 knee alignment-oriented DBE group. Proprioception was assessed by dynamic postural stability using postural stabilometry. Neuromuscular control and knee muscle strength were measured for acceleration time and peak torque in quadriceps muscle using an isokinetic device. Patient-reported outcomes were evaluated using a visual analog scale for pain and the Kujala Anterior Knee Pain Scale. There was greater improvement in dynamic postural stability (0.9 ± 0.3 vs 1.2 ± 0.5; 95% confidence interval [CI]: 0, 0.6; Effect size: 0.72; P = .021) and quadriceps AT (40.5 ± 14.3 vs 54.1 ± 16.9; 95% CI: 2.9, 24.2; Effect size: 0.86; P = .014) in the DBE group compared to the SBE group. Knee alignment-oriented DBE can be more effective in improving dynamic postural stability and quadriceps muscle reaction time compared with the knee alignment-oriented SBE in PFPS patients with dynamic knee valgus.