The reliability and validity of a designed setup for the assessment of static back extensor force and endurance in older women with and without hyperkyphosis.

ObjectiveThe purpose of this study was to investigate the intra-rater reliability and validity of a designed load cell setup for the measurement of back extensor muscle force and endurance.ParticipantsThe study sample included 19 older women with hyperkyphosis, mean age 67.0 ± 5.0 years, and 14 older women without hyperkyphosis, mean age 63.0 ± 6.0 years.MethodsMaximum back extensor force and endurance were measured in a sitting position with a designed load cell setup. Tests were performed by the same examiner on two separate days within a 72-hour interval. The intra-rater reliability of the measurements was analyzed using intraclass correlation coefficient (ICC), standard errors of measurement (SEM), and minimal detectable change (MDC). The validity of the setup was determined using Pearson correlation analysis and independent t-test.ResultsUsing our designed load cell, the values of ICC indicated very high reliability of force measurement (hyperkyphosis group: 0.96, normal group: 0.97) and high reliability of endurance measurement (hyperkyphosis group: 0.82, normal group: 0.89). For all tests, the values of SEM and MDC were low in both groups. A significant correlation between two documented forces (load cell force and target force) and significant differences in the muscle force and endurance among the two groups were found.ConclusionThe measurements of static back muscle force and endurance are reliable and valid with our designed setup in older women with and without hyperkyphosis

The Reliability of Standing Sagittal Measurements of Spinal Curvature and Range of Motion in Older Women With and Without Hyperkyphosis Using a Skin-Surface Device.

OBJECTIVE:The purpose of this study was to investigate the intrarater reliability of a skin-surface instrument (Spinal Mouse, Idiag, Voletswil, Switzerland) in measuring standing sagittal curvature and global mobility of the spine in older women with and without hyperkyphosis. METHODS:Measurements were made in 19 women with hyperkyphosis (thoracic kyphosis angle ≥50°), mean age 67 ± 5 years, and 14 women without hyperkyphosis (thoracic kyphosis angle <50°), mean age 63 ± 6 years. Sagittal thoracic and lumbar curvature and mobility of the spine were assessed with the Spinal Mouse during neutral standing, full spinal flexion, and full spinal extension. Tests were performed by the same examiner on 2 days with a 72-hour interval. The intrarater reliability of the measurements was analyzed using the intraclass correlation coefficient, standard error of measurement and minimal detectable change. RESULTS:Intraclass correlation coefficients ranged from 0.89 to 0.99 in both groups. The standard errors of measurement ranged from 1.02° to 2.06° in the hyperkyphosis group and from 1.15° to 2.22° in the normal group. The minimal detectable change ranged from 2.85° to 5.73° in the hyperkyphosis group and from 3.20° to 6.17° in the normal group. CONCLUSIONS:Our results indicated that the Spinal Mouse has excellent intrarater reliability for the measurement of sagittal thoracic and lumbar curvature and mobility of the spine in older women

The effect of forward head posture on cervical joint position sense

A number of studies have investigated the effect of age, trauma, disease and fatigue on cervical joint position sense. However, there is an absence in data regarding the role of posture on proprioception. The aim of the current study was to investigate the effect of Forward Head Posture (FHP) on cervical joint position sense. Twenty Forward Head Posture volunteers (14 women, 6 men), with the mean age of 23.94 (SD=3.26) years, and 17 normal head posture volunteers (8 women, 9 men) with the mean age of 23.50 (SD=2.68) years were asked to perform the Cervicocephalic relocation test (CRT) to the neutral head position (NHP). The aim of this test was to evaluate the participants' ability to relocate the head to neutral position after they actively rotated it to left and right sides. Three trials were performed for each rotation to the left and right. In order to assess cervical joint repositioning accuracy, Absolute, Constant and Variable errors were used. No significant difference in repositioning errors was observed between experimental and control group in absolute and constant errors (P>0.05); however, compared to normal group, Forward Head Posture subjects manifested significantly higher levels of variable errors (P<0.05). Forward Head Posture can significantly affect the positioning consistency of cervical proprioception. Nonetheless, further investigation on the effect of Forward Head Posture on cervical proprioception in altered situations is recommended.

Knee Muscle Reciprocal Co-Activation in Patellofemoral Pain Syndrome During Isokinetic Exercise: A Voluntary Response Index Analysis

Introduction: The origin of the Patellofemoral Pain Syndrome (PFPS) is not still completely clear and may have a biomechanical or biochemical cause. Motor control dysfunction may have a role in this condition. Voluntary Response Index (VRI) is able to show changes in the central nervous system motor output that occur with intervention, recovery, or progression of the disorder. Therefore, the outcomes may contribute to offer another tool for PFPS motor control evaluation. The aim of the present study, therefore, was to assess the changes in the quadriceps and hamstring reciprocal coactivation patterns that may be observed in individuals with PFPS using the VRI. Methods and Materials: A total of 24 female participants, 12 with sound knees and 12 with PFPS participated in the present study. The study was accomplished in the Biomechanics Laboratory at Rehabilitation School of Tehran University of Medical Sciences in 2015. The participants sat on a Biodex dynamometer. They were asked to perform 10 continuous knee extension and flexion motions with maximal strength at 45˚/s and 300˚/s, distinctly. Simultaneously, electromyographic activities of the vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF), and biceps femoris (BF) were recorded and VRI was calculated. A two-way analysis of variance was run to assess the effect of group and velocity on the VRI (similarity index and magnitude). Results: There was no velocity or group main effect observed for the VRI (P>0.05). In addition, no significant velocity × group interaction was found for the VRI (P>0.05). Conclusion: PFPS may not be linked to altered quadriceps and hamstring reciprocal co-activation patterns during isokinetic exercise. In addition, angular velocity may not be an important parameter in voluntary motor control assessment during isokinetic exercise.Keywords: Reciprocal co-activation; Voluntary response index; Patellofemoral pain syndrome; Isokineti

Training Interventions Change Relative Power Spectrum of Alpha After Anterior Cruciate Ligament Deficiency in Athletes

Introduction: In individuals with anterior cruciate ligament deficiency (ACLD), defective sensory and motor neuroplasticity occurs in the central nervous system (CNS) due to defects in sensory afferents. To successfully restore ACLD individuals to pre-injury conditions, it is necessary to modify the neuroplasticity created in the CNS by prescribing more appropriate training. For this aim, in this study, we used perturbation training differently. Materials and Methods: Thirty athletes with unilateral anterior cruciate ligament (ACL) rupture were randomly assigned to the perturbation and standard training groups. The training program of two groups was performed in three intermittent sessions per week for one month. The relative power spectrum of alpha of quantitative electroencephalography (QEEG) was measured in three tasks: (1) the single-leg jump-landing, (2) the single-leg stance with opened eyes, and (3) the single-leg stance with closed eyes. Results: The perturbation training group only showed significant symmetry in the relative power spectrum of alpha between the two limbs in the single-leg jump-landing test (p=0.92, ES=0.04) in comparison pre-post test. Also, this group showed high symmetry in the alpha band in the single-leg stance test with closed eyes (p=0.53, ES=0.16). Conclusion: The results of the present study showed that both mechanical perturbation and standard training are suitable for transporting ACLDs back to sports. It also seems that mechanical perturbation training had higher effectiveness in modifying the CNS alpha power

Investigation of the Effects of Estrogen and Progesterone Hormones on Active Knee Joint Position Sense in Healthy Women in Different Phases of a Menstrual Cycle

Abstract The proprioceptive system is actually a sensory system based on an individual’s knowledge of the body. The aim of this study was to investigate the effect of estrogen and progesterone hormones on understanding and to recognize the proprioceptive sense the knee joint in healthy women during the menstrual cycle. Fifteen healthy women with regular menstrual cycles participated in this study. The estrogen and progesterone levels were evaluated during a cycle in the follicular, ovulation, and luteal phases. The effect on the sense of perception and cognition of the proprioceptive knee joint in two directions (extension and flexion), by target angle reconstruction at 30° was studied. The results showed that female sex hormones affect the knee active Joint Position Sense (JPS). In the extensions, the changes of the menstrual cycle affect the JPS in constant error during the ovulation phase. In the flexion, changes in the menstrual cycle affect the JPS in constant, absolute, and variable error during the luteal phase. The findings of this study show that the menstruation phases can change the active JPS at knee joint. Since the outbreak of joint problems, especially in the knee joint, is higher in women than in men, it was predicted that hormonal changes during the menstrual cycle affect the proprioceptive cognition of the knee joint, which in turn increases the percentage of knee injuries in women

Whole-Body Vibration and the Prevention and Treatment of Delayed-Onset Muscle Soreness

Context: Numerous recovery strategies have been used in an attempt to minimize the symptoms of delayed-onset muscle soreness (DOMS). Whole-body vibration (WBV) has been suggested as a viable warm-up for athletes. However, scientific evidence to support the protective effects of WBV training (WBVT) on muscle damage is lacking. Objective: To investigate the acute effect of WBVT applied before eccentric exercise in the prevention of DOMS. Design: Randomized controlled trial. Setting: University laboratory. Patients or Other Participants: A total of 32 healthy, untrained volunteers were randomly assigned to either the WBVT (n 5 15) or control (n 5 17) group. Intervention(s): Volunteers performed 6 sets of 10 maximal isokinetic (606/s) eccentric contractions of the dominant-limb knee extensors on a dynamometer. In the WBVT group, the training was applied using a vibratory platform (35 Hz, 5 mm peak to peak) with 1006 of knee flexion for 60 seconds before eccentric exercise. No vibration was applied in the control group. Main Outcome Measure(s): Muscle soreness, thigh circumference, and pressure pain threshold were recorded at baseline and at 1, 2, 3, 4, 7, and 14 days postexercise. Maximal voluntary isometric and isokinetic knee extensor strength were assessed at baseline, immediately after exercise, and at 1, 2, 7, and 14 days postexercise. Serum creatine kinase was measured at baseline and at 1, 2, and 7 days postexercise. Results: The WBVT group showed a reduction in DOMS symptoms in the form of less maximal isometric and isokinetic voluntary strength loss, lower creatine kinase levels, and less pressure pain threshold and muscle soreness (P , .05) compared with the control group. However, no effect on thigh circumference was evident (P , .05). Conclusions: Administered before eccentric exercise, WBVT may reduce DOMS via muscle function improvement. Further investigation should be undertaken to ascertain the effectiveness of WBVT in attenuating DOMS in athletes. Key Words: eccentric exercise, muscle strength, creatine kinase Key Points N After a bout of eccentric exercise, a whole-body vibration training session was associated with reduced symptoms of delayed-onset muscle soreness when compared with no vibration training. N Maximal isometric and isokinetic voluntary strength loss, plasma creatine kinase level, pressure point threshold, and muscle soreness were less than in the control group. N No effect on thigh circumference was seen

Effect of 670 Nm Laser Beam on the Action Potentials of Sural Nerve in Healthy Individuals

Introduction: Low Level Laser (LLL) is being used in physiotherapy for pain relief in various pathologies and particularly on peripheral nerve entrapments. In the present study, the effect of LLL on the electrophysiological parameters of sural in humans was investigated. The results might be used as a basis for further clinical research in abnormal conditions. Methods and Materials: Thirty-eight normal men voluntarily participated in the current study and 670 nm LLL beam was applied to the left sural nerve at 5 points for 10 sessions. The electrophysiological parameters such as onset latency, peak latency, negative peak amplitude, peak to peak amplitude, and duration were measured before and after the application of LLL (0.5, 1.5 & 2.5 J/cm² energy density). Results: Overall, 670 nm laser beam increased the latency and reduced the nerve conduction velocity (NCV). In addition, LLL beam decreased the amplitude of action potentials. Among the various values of energy densities, application of 2.5 J/cm² had the most effective results (P < 0.001). Conclusion: These results might suggest that 670 nm laser beam could affect the latency and reduce the NCV in sural nerve of human. Probably, LLL affects the bioelectric and bioenergetic properties of the neural biomembrane. These findings might have clinical signlificance in non-surgical treatment of entrapment syndromes, such as carpal, tarsal syndromes and trigeminal entrapment in human. Further investigations are needed to elucidate the effects of LLL beam on the human peripheral nerves in pathological conditions.Keywords: Low-level laser, Sural nerve, Electrophysiology, Pai

A novel laryngeal palpatory scale (LPS) in patients with muscle tension dysphonia

Objectives: Laryngeal palpation is a routine clinical method for evaluation of patients with muscle tension dysphonia (MTD). The aim of this study was to develop a new comprehensive valid and reliable “laryngeal palpatory scale” (LPS), based on psychometric criteria. Methods: The scale items were selected based on an in-depth analysis of the literature and an expert focus group. Scale item generation and item reduction were followed by a psychometric assessment. Qualitative and quantitative content validity (the content validity ratio (CVR), content validity index (CVI)), the qualitative face validity, and the inter-rater reliability were determined. For this purpose, 531 patients were assessed and finally 55 patients with primary MTD (26 women, mean age: 40.8 years, SD: 12.5; 29 male, mean age: 41.6 years, SD: 11.8) participated in the study. A weighted kappa (k*) statistic was used to examine the inter-rater reliability for each single item. Results: Based on the CVR, three items were omitted because they had a score of less than 0.62. The CVI for all remaining items was greater than 0.79 and the scale CVI was equal to 0.96. The final 45 items were a result of the study. The inter-rater reliability for each single item ranged from 0.41 to 1, indicating moderate to almost perfect agreement. Conclusions: The LPS is a reliable and valid instrument for assessing patients with MTD. However, future studies are needed to provide adequate data on sensitivity, specificity, concurrent validity, and cutoff scores