Gender-Related Differences in Reliability of Thorax, Lumbar, and Pelvis Kinematics During Gait in Patients With Non-specific Chronic Low Back Pain

OBJECTIVE: To evaluate test-retest reliability of trunk kinematics relative to the pelvis during gait in two groups (males and females) of patients with non-specific chronic low back pain (NCLBP) using three-dimensional motion capture system. METHODS: A convenience sample of 40 NCLBP participants (20 males and 20 females) was evaluated in two sessions. Participants were asked to walk with self-selected speed and kinematics of thorax and lumbar spine were captured using a 6-infrared-cameras motion-analyzer system. Peak amplitude of displacement and its measurement errors and minimal detectable change (MDC) were then calculated. RESULTS: Intraclass correlation coefficients (ICCs) were relatively constant but small for certain variables (lower lumbar peak flexion in female: inter-session ICC=0.51 and intra-session ICC=0.68; peak extension in male: inter-session ICC=0.67 and intra-session ICC=0.66). The measurement error remained constant and standard error of measurement (SEM) difference was large between males (generally ≤4.8°) and females (generally ≤5.3°). Standard deviation (SD) was higher in females. In most segments, females exhibited higher MDCs except for lower lumbar sagittal movements. CONCLUSION: Although ICCs were sufficiently reliable and constant in both genders during gait, there was difference in SEM due to difference in SD between genders caused by different gait disturbance in chronic low back pain. Due to the increasing tendency of measurement error in other areas of men and women, attention is needed when measuring lumbar motion using the method described in this study.

Correction: Gender-Related Differences in Reliability of Thorax, Lumbar, and Pelvis Kinematics During Gait in Patients With Non-specific Chronic Low Back Pain

In this article, the affiliation of the first author should be changed.

[Evaluation of reliability of H-reflex recruitment curve parameters of soleus and lateral gastrocnemius muscles in assessment of motor neuron pools excitability]

In Recent years, recording of the H-reflex recruitment curve for assessment of the excitability of group I[a] afferent monosynaptic reflex has been growing. The purpose of this study was to evaluate the reliability of H-reflex recruitment curve parameters of gasterosoleus muscle in the assessment of motor neuron pool excitability. In this descriptive study, 50 non-athlete healthy volunteers were assessed. Percutaneously, 40 electrical pulses of 1 millisecond duration and 3 stimulations per each stimulus intensity were induced on tibial nerves and H-reflex recruitment curve were recorded in 4 phases. Also, each person was assessed in two sessions with 1-week interval. The intraclass correlation coefficients [ICCs] was obtained between 0.97-0.99 for inter-session reliability of intensity for recording the threshold, H[Max] and H[Last] reflexes, amplitude of H[Max], and the total slope of the ascending and descending arms. The inter-session correlation coefficient [test-retest] of these variables were obtained between 0.91-0.95 for soleus muscle, and the inter-session ICCs for peak-to-peak amplitude of H[Max] and the total slope of the ascending arm of gastrocnemius were obtained 0.65 and 0.67. The slope of initial and final three points of the ascending arm revealed a different reliability in inter-session and intra-session reliability analysis [0.64-0.96]. The reliability analysis showed a high inter-session and intra-session ICCs for the functional principal components of soleus recruitment curve. Also, recruitment curve parameters, such as intensity for record of threshold and H[Max] of soleus and lateral gastrocnemius muscles as well as total slope of ascending and descending arms, and peak to peak amplitude of H[Max] of soleus muscle had a very high Reliability

[Learning effects of the biodex balance system during assessment of postural task with in test-retest measurements]

Balance assessment plays a major role in treatment and rehabilitation of patients. Recently scientists have designed a new device with a dynamic multi-axial tilting platform to aid in joint rehabilitation and enhance proprioceptive mechanisms and postural assessment, called Biodex balance system [BBS]. Repetition of exposure to the BBS causes learning or familiarization. Therefore, it can't be sure that the changes seen in the stability index, are due to the effect of the learning or intervention. The purpose of this study was to evaluate the learning effects of test-retest postural task and to set the learning curve and test-retest reliability of dynamic standing balance using BSS. Ten healthy non-athletic persons participated in this study. The volunteers were asked to stand on BBS with two levels of difficulty on their dominant leg with open eyes. Two trials of 10 repetitions were applied at difficulty level of 4 and 8 with 30 minutes rest between each test and 30 minutes rest between two trials. Total stability index [TSI], anteroposterior [APSI] and mediolateral [MLSI] were registered. The effect of repetition of hard postural task on biodex was significantly different in trial 6 from 1-5 [P<0.05]. The effect of repetition of easy postural task on biodex was significantly different in trial of 5 from 1-4 [P<0.05]. After learning, we found no significant difference in mean stability index of test condition of each trials in reliability assessment so the intra-class correlation coefficients ranged from 0.83 to 0.92. Tests at lower stability level produced the higher ICCs [0.90-0.92]. There was a very strong correlation between total stability index and AP stability index using Pearson correlation coefficient [P<0.01, r = 88%]. The results showed that repeating a task on the BBS for five times or more have learning effects. So, while evaluating postural stability in a simple task which has more than five repetitions, learning effect should be take in to account and in difficult postural task it is sex repetitions that can have learning effects

Efficacy of low level laser on knee osteoarthritis treatment

Osteoarthritis [OA] is the most common disease in all joints that is generally treated with drugs such as non-steroidal anti-inflammatory drugs [NSAIDs] and physiotherapy. Although NSAIDs are widely used to treat the pain and stiffness associated with knee OA, the high incidence of serious upper gastrointestinal side effect with NSAIDs can limit their use. Therefore physiotherapy plays a vital role on OA treatments. One modality that has mostly used recently is low level laser. Despite its widespread usage, the results of the experimental and clinical studies are conflicting. However, very few controlled clinical studies of low-power laser applied for the treatment of knee OA have been reported and the findings of these studies are also contradictory. This study was performed to assess the effects of low level laser on knee OA. This single-blinded clinical trial was performed on 36 adult patients [45-75 years old] with knee OA. The patients were randomly divided into two groups of active laser with standard treatment and placebo laser with standard treatment. A Gal-Al-As diode laser device with a power output of 30 mW and a wavelength of 830 nm was used in the study. The standard treatment was ultrasound, transcutaneous electrical nerve stimulation, infrared, the straight-leg raise test in supine position, and the subjects were treated for ten sessions, 5 times per week and for a period of two weeks. Then pain at rest, duration of morning stiffness, active range of knee flexion and the quality of life with WOMAC index were assessed before and after the intervention. Although, there were significant differences before and after the intervention of all criteria in both groups [p<0.05], no significant differences were observed between two groups with respect to those criteria. This study revealed that application of low level laser is not efficient for the knee OA treatment