Isokinetic and functional parameters in patients following reconstruction of the anterior cruciate ligament

Both isokinetic testing and functional tests are commonly used to evaluate patients following reconstruction of the anterior cruciate ligament (ACLR). To determine the relationship of scores on an isokinetic test to scores on a variety of lower extremity functional tests ten healthy subjects and eleven ACLR patients at least six months after surgery performed knee isokinetic test at 60 and 180 deg/sec and three functional tests: leg vertical jump, single hop, and triple cross-over hop for distance. Correlation coefficients of isokinetic peak torque to body weight and functional testing were not significant at the P < 0.05 level in patients or control subjects, whi1e ratio of involved to uninvolved knee quadriceps isokinetics peak torque and Limb Symmetry Index (LSI) of functional test were significant at the P < 0.05 level (r=0.54 to 0.97). These results indicate a significant relationship between the LSI of various functional tests and side-to-side ratio of isokinetic testing just in ACLR patients. © 2005 - IOS Press and the authors. All rights reserved

Functional outcome of lower limb following anterior cruciate ligament reconstruction; a prospective clinical study

Background: Both isokinetic testing and functional tests are commonly used to evaluate anterior cruciate ligament reconstructed (ACLR) patients. The object of this study was to evaluate motor performance of the knee and determine the relationship of isokinetic test scores to scores on a variety of lower extremity functional tests. Methods: Ten healthy subjects and eleven ACLR patients at least six months after surgery performed the following: knee isokinetic tests at 60 and 180 deg/sec; three functional tests including leg vertical jump, single hop, and triple cross-over hop for distance. The International Knee Document Committee Subjective Knee Evaluation Form (IKDCSKEF) was used to score the self-assessment of each study participant. Paired T-test was used to compare the involved and uninvolved knee. Pearson correlation coefficients were used to determine the relationship between the scores on the isokinetic test and functional tests. Significance was determined by P<0.05. Results: IKDCSKEF score was significantly lower in patients than control subjects. Quadriceps peak torque and functional test scores were significantly lower in the involved knee of the ACLR subjects compared to the uninvolved knee. Correlation coefficients of isokinetic peak torque to body weight and functional testing were not significant in patients or control subjects, whi1e the limb symmetry index (LSI) of the quadriceps isokinetics peak torque to body weight and the LSI of the functional tests were significant (r = 0.54 to 0.97). Conclusion: These results indicate a significant relationship between the LSI of various functional tests and the LSI of isokinetic testing among ACLR patients. Thus, in situations where an isokinetic dynamometer is not available, the LSI of functional tests can be used to estimate quadriceps deficiency for ACLR patients. © 2008, Tehran University of Medical Sciences. All rights reserved

A preliminary study into the criterion validity of the modified Modified Ashworth scale using the new measure of the alpha motoneuron excitability in spastic hemiplegia

The Modified Ashworth Scale (MAS) is the most widely used clinical test for the measurement of muscle spasticity. This scale that suffers from limitations and lack of reliability and validity has recently been remodified. The aim of the present study is to investigate the criterion validity of the new Modified MAS(MMAS) in the upper limb in post-stroke hemiplegia, using the Hslope/Mslope (Hslp/Mslp) as a novel index of alpha motor neuron excitability. Prior to the validity study, the reliability of the MMAS was evaluated in 30 hemiplegic patients. The raters agreed on 23 patients (0.76). The MMAS had good inter-rater reliability (κ= 0.63, SE = 0.11, p 0.05): There was also no relationship between the clinical scale of MMAS and either the traditional Hmax/ Mmax ratio (r = -0.06) or the new index Hslp/Mslp (r = 0.24) of spinal excitability. This preliminary study recruited a small number of patients, and failed to confirm a linear correlation between these variables. A study with a larg number of patients is suggested to clarify the outcome

Short-term effect of kinesiology taping on pain, functional disability and lumbar proprioception in individuals with nonspecific chronic low back pain: a double-blinded, randomized trial

Background: This study aimed to evaluate the effect of kinesiology taping (KT) on lumbar proprioception, pain, and functional disability in individuals with nonspecific chronic low back pain (CLBP). Methods: Thirty individuals with nonspecific CLBP participated in this double-blinded, randomized clinical trial from July 2017 to September 2018. The participants were randomized into two groups: KT (n = 15) and placebo group (n = 15). KT was applied with 15�25 tension for 72 h, and placebo taping was used without tension. Lumbar repositioning error was measured by a bubble inclinometer at three different angles (45° and 60° flexion, and 15° extension) in upright standing. Pain and disability were assessed by the Short-Form McGill Pain Questionnaire and Oswestry Disability Index, respectively. All measurements were recorded at baseline and 3 days after taping. Results: Pain and disability scores reduced 3 days after taping in the KT group with large effect sizes (p 0.05). Also, only constant error of 15° extension showed a moderate correlation with disability (r = 0.39, p = 0.02). Conclusion: KT can decrease pain and disability scores after 3 days of application. Although placebo taping can reduce pain, the effect of KT is higher than placebo taping. The findings do not support the therapeutic effect of KT and placebo taping as a tool to enhance lumbar proprioception in patients with nonspecific CLBP. Trial registration: The study prospectively registered on 21.05.2018 at the Iranian Registry of Clinical Trials: IRCT20090301001722N20. © 2020, The Author(s)

Effect of static neck flexion in cervical flexion-relaxation phenomenon in healthy males and females

Introduction: Neck pain is a common musculoskeletal disorder, especially among skilled workers who must keep their necks in a flexed position frequently during the day. The present study investigated changes in cervical flexion-relaxation phenomenon parameters after sustained neck flexion. Methods: The participants were 40 healthy subjects grouped by gender (20 females, 20 males). They were exposed to static neck flexion at the full angle of cervical flexion for 10 min. Each subject underwent three trials of cervical flexion and re-extension before and after this period. Differences in onset and cessation angle of flexion-relaxation phenomenon, maximum neck flexion angle, amplitude of neck muscle activation and flexion-relaxation ratio were evaluated. Results: The maximum neck flexion angle significantly increased after sustained flexion. The onset of flexion-relaxation was significantly delayed during flexion, but cessation angle remained unchanged. Myoelectric activity of the cervical erector spinae muscles increased significantly after maintaining flexion, especially in female subjects. The flexion-relaxation ratio also decreased significantly. Conclusion: It was concluded that 10 min of static flexion results in a delay in flexion-relaxation phenomenon and a shortened silence period. Also the cervical erector spinae muscles are required to be active longer and generate more activity. These neuromuscular changes may be a risk factor for neck pain. © 2015 Elsevier Ltd

Comparison of concentric isokinetic dominant shoulder internal and external rotator torque between professional female volleyball and tennis players

Background: The purpose of this study was to measure isokinetic maximum and average peak torque of internal and external rotators of glenohumeral joint in volley ball and tennis players Methods: This study was performed on 17 professional female athletes (7 tennis players &amp;10 volleyball players) with age ranged 18-28 years. The subjects had played in a skilled team for more than 3 years. They were free from injury to their dominant shoulder in the past year. Subjects performed a five minute warm up by shoulder wheel and Maximum average Peak Torque (APT) were obtained unilaterally by a Biodex System 3 with the arm of players in 90 degree abduction at 120,180 &amp; 210 o/s. Players performed five trails of concentric movements with 30 second rest between them. Results: Maximum and average of maximum torques of shoulder rotator, in both groups, expect for internal rotators of tennis players, reduced by increase of movement speed (P&lt;0.05). There are not significant difference between two groups in maximum, average of maximum torques and normalized data (ratio of maximum torque to weight). There is significant difference between two groups in percentage of APT of External rotator / Internal rotator ratio at 210 o/s (P&lt;0.05). Conclusion: Volleyball and tennis have no effect on isokinetic strength of shoulder rotators. In high speed, ratio of External rotator / Internal rotator is reduced. This indicates that increase in movement speed increase internal rotator in comparison to external rotator in these professional female athletes

Effects of peroneal muscles fatigue on dynamic stability following lateral hop landing: Time to stabilization versus dynamic postural stability index

Context: Dynamic stability is a necessary requirement in many sports competitions. Muscle fatigue, which can impair stability, may be occurred in many sports competitions in which lateral movements and landing repeated frequently. Objective: To assess the effects of peroneal muscles fatigue on dynamic stability following lateral hop landing through measuring time to stabilization (TTS) and dynamic postural stability index (DPSI). Design: Quasi-experimental. Setting: Laboratory study. Participants: A total of 20 recreationally active, healthy males with no lower-extremity injury during the previous 6 months participated in this study. Intervention: Participants performed a lateral hop on a force plate before and immediately after a fatigue intervention using a Biodex dynamometer. For inducing fatigue, the participant made a prolonged eversion effort with 40 of the maximal voluntary contraction. Fatigue was met when the eversion torque declined by 50 of the initial value. TTS and DPSI were calculated using sequential averaging method and relevant formulas, respectively. Main Outcome Measures: Premeasures and postmeasures of TTS in the anteroposterior, mediolateral and vertical directions, resultant vector of TTS, stability indices in the anteroposterior, mediolateral and vertical directions, and DPSI. Results: Means of the DPSI or its components did not change significantly due to fatigue (P > .05). Means of the TTS in the anteroposterior and mediolateral directions, and the mean of the resultant vector of the TTS increased significantly after fatigue (P < .05). Conclusions: The question that the dynamic stability is affected or not affected by fatigue depends on which of the TTS or DPSI is used for analysis. The TTS may be a sensitive measure to detect subtle changes in postural stability due to fatigue. But, the DPSI which may be changed after a more strenuous fatigue may be related to actual fatiguing situations. © 2019 Human Kinetics, Inc

The effect of exertion level on activation patterns and variability of trunk muscles during multidirectional isometric activities in upright posture

STUDY DESIGN.: An experimental design to investigate activation patterns of trunk muscles during multidirectional exertions. OBJECTIVES.: To evaluate trunk muscle activation patterns in varying directions and moment magnitudes during an isometric task, and to investigate the effects of angle and level of isometric exertion on the electromyography (EMG) variability of trunk muscles in upright posture. SUMMARY OF BACKGROUND DATA.: Few studies have investigated trunk muscle activation patterns in multidirectional exertions with different moment magnitudes. METHODS.: A total of 12 asymptomatic male subjects were participated in the study. The EMG activity of 10 selected trunk muscles was collected in the 3 seconds end point matching tasks in 8 angles and 3 magnitudes of exertion. Trunk muscle activation patterns were examined using EMG tuning curves and measuring preferred direction (mean vector direction) and the index of spatial focus. The effect of exertion level on these measures was investigated by Rao test. The effects of angle and level of exertion on the EMG variability of trunk muscles were tested by analysis of variance with repeated measures design. RESULTS.: No significant difference in EMG tuning curves, preferred direction, and the index of spatial focus was found for each muscle studied across exertion levels (P > 0.05). The index of spatial focus of most muscles studied was not changed with increasing moment magnitude. EMG variability of trunk muscles was significantly affected by angle and level of exertion and their interaction effect (P < 0.001). CONCLUSION.: Consistent activation patterns of trunk muscles were found within and among subjects in different moment magnitudes. The index of spatial focus indicated that probably no shift to a higher cocontraction strategy has been adapted with increasing moment magnitude. The results suggested that increased EMG variability of trunk muscles in asymmetric exertions may be associated with lower trunk controllability during combined exertions. © 2010, Lippincott Williams & Wilkins

The effect of static neck flexion on mechanical and neuromuscular behaviors of the cervical spine

Occupations that involve sustained or repetitive neck flexion are associated with a higher incidence of neck pain. Little in vivo information is available on the impact of static neck flexion on cervical spinal tissue. The aim of this study was to assess changes in mechanical and neuromuscular behaviors to sustained neck flexion in healthy adults. Sixty healthy subjects aged 20�35 years participated in this study. The participants were exposed to static neck flexion at a fixed angle of full flexion for 10 min. Mechanical and neuromuscular responses of the cervical spine to sudden perturbations were measured pre- and post-exposure. Magnitude of load-relaxation during flexion exposure, stiffness, peak head angular velocity, and reflexive activities of cervical muscles were recorded. Effective neck stiffness decreased significantly, especially in female participants (P = 0.0001). The reflexive response of the cervical erector spinae muscles to head perturbation delayed significantly (P = 0.0001). Peak head angular velocity was significantly increased after exposure to neck flexion for 10 min, especially in female participants (P = 0.001). In the present study, static flexion resulted in changes in mechanical and neuromuscular behavior of the cervical spine, potentially leading to decreased stiffness of the cervical spine. The results confirm the importance of maintaining a correct head and neck position during work and improving the work environment to reduce the cervical spinal load and work-related neck pain. © 2018 Elsevier Lt

Disturbance of neck proprioception and feed-forward motor control following static neck flexion in healthy young adults

The highly complex proprioceptive system provides neuromuscular control of the mobile cervical spine. Static neck flexion can induce the elongation of posterior tissues and altered afferent input from the mechanoreceptors. The purpose of this study was to examine the effect of prolonged static neck flexion on neck proprioception and anticipatory postural adjustments. Thirty-eight healthy participants (20 females and 18 males) between the ages of 20�35 years with no history of neck, low back, and shoulder pain enrolled in this study. Neck proprioception and anticipatory muscle activity were tested before and after 10-min static neck flexion. For assessment of neck proprioception, each participant was asked to perform 10 trials of the cervicocephalic relocation test to the neutral head position after active neck rotation to the left and right sides. Anticipatory postural adjustments were evaluated during a rapid arm flexion test. Following the flexion, the absolute and variable errors in head repositioning significantly increased (p < 0.05). The results also showed that there was a significant delay in the onset of myoelectric activity of the cervical erector spinae muscles after flexion (p = 0.001). The results of this study suggested that a 10-min static flexion can lead to changes in the neck proprioception and feed-forward control due to mechanical and neuromuscular changes in the viscoelastic cervical spine structures. These changes in sensory-motor control may be a risk factor for neck pain and injury. © 201