Viscoelastic response of the lateral side of the ankle to cyclic inversion: a time course analysis.

Although important, viscoelastic behavior of the ankle's lateral side has rarely been studied. The present study assesses the viscoelastic behavior during cyclic inversions. Eighteen recreationally active healthy males underwent 40 passive cyclic inversions using a Biodex dynamometer at 5 °/s through 80% of maximum range of motion. Energy absorption and restitution and dissipation coefficient were calculated for each repetition. Changes in the mean of the dependent variables for repetitions 1 (R1 ), R5 , R10 , R15 , R20 , R25 , R30 , R35 and R40 were compared by three one-way analyses of variance with repeated measures. There was a significant difference between the means of energy absorption for the selected repetitions from R1 to R20 (P < 0.01), but there was no significant difference between them from R20 to R40 (P > 0.05). There was no significant difference between the means of energy restitution for the selected repetitions (P > 0.05). Whereas there was no significant difference consecutively between the means of dissipative coefficient for the selected repetitions (P > 0.05), there was a significant difference between the means of R30 or R40 relative to the baseline (P < 0.005). The decrease in the energy absorbed and the dissipation coefficient following repeated inversions may be due to the slippage of collagen fibers. The decrease in the shock absorbing ability of the tissues may expose them to injury.

Effects of cyclic static stretch on fatigue recovery of triceps surae in female basketball players.

Static stretch is a safe and feasible method which usually is used before exercise to avoid muscle injury and to improve muscle performance. The purpose of this study was to determine the effects of cyclic static stretch (CSS) on fatigue recovery of triceps surae (TS) in female basketball players. Nine athlete volunteers between 20 and 30 years participated in this study containing two sessions. After warm-up a pressure cuff was fastened above the knee joint and its pressure was increased to 140 mmHg. The subjects were asked to perform one maximum voluntary contraction (MVC) followed by a fatigue test including maximum isometric fatiguing contraction of TS. These steps were similar in both sessions. Then, a two-minute rest was included in the first session while 4 static stretches were performed to TS in the second session. After interventions, one MVC was done and the pressure cuff was released. During these steps, peak torque (PT) and electromyography (EMG) were recorded. The amount of lower leg pain was determined by the visual analogue scale (VAS). The value of PT increased significantly after CSS but its increase was not significant after rest. It seems that the effects of rest and CSS on the EMG parameters, PT and pain are similar.

The correlation between Modified Ashworth Scale scores and the new index of alpha motoneurones excitability in post-stroke patients.

The Modified Ashworth Scale (MAS) is currently a widely used clinical scale to evaluate muscle spasticity. However, it lacks reliability and the validity, of the MAS as a clinical measure of muscle spasticity has been challenged. The aim of the present study was to examine the validity of the MAS in patients with wrist flexor spasticity after stroke by using the Hslope/Mslope (Hslp/Mslp) ratio as the new index of alpha motoneuron excitability. Twenty-seven adult patients (14 women and 13 men) with first ever stroke resulting in hemiplegia with a mean (SD, range) age of 57.9 (11.6, 37-75) were included in the study. The main outcome measures were the MAS for the clinical assessment of spasticity, and the Hslp/Mslp for the neurophysiological evaluation. There was not a significant correlation between the MAS scores and Hslp/Mslp ratio (r = 0.38, p > 0.05). The mean of the Hslp/Mslp did not show a hierarchical increase with the MAS scores. The findings indicate that the MAS is not a valid and ordinal level measure of muscle spasticity.

Neurophysiological examination of the Modified Modified Ashworth Scale (MMAS) in patients with wrist flexor spasticity after stroke.

The Modified Modified Ashworth Scale (MMAS) is a clinical test for the measurement of spasticity. The aim of the present study was to examine the validity of the MMAS in patients with wrist flexor spasticity after stroke. 27 adult patients (14 women and 13 men) with first ever stroke resulting in hemiplegia with a mean (SD, range) age of 57.9 (11.6, 37-75) were included in the study. The outcome measures were the MMAS for the clinical assessment of spasticity, the Hslope/Mslope (Hslp/Mslp), and the H(max)/M(max) ratio for the neurophysiological evaluation. The mean of the Hslp/Mslp and the H(max)/M(max) were higher in patients with worse MMAS grades but the differences were not statistically significant. There was a significant positive correlation between the MMAS scores and Hslp/Mslp ratio as the new index of alpha motoneurone excitability or traditional index of H(max)/M(max) ratio (r = 0.39, p = 0.04). It is concluded that the MMAS to be a valid measure of spasticity after stroke.

A comparative study of whole body vibration training and conventional training on knee proprioception and postural stability after anterior cruciate ligament reconstruction.

OBJECTIVE: To compare the effect of a whole body vibration training (WBVT) programme with a conventional training (CT) programme on knee proprioception and postural stability after anterior cruciate ligament (ACL) reconstruction. METHODS: Twenty athletes with unilateral ACL reconstruction were randomly assigned to the WBVT or CT group; all participants received 12 sessions of WBVT or conventional training. Absolute error in joint repositioning for two target angles (30 degrees and 60 degrees ) was measured with the Biodex dynamometer; bilateral dynamic postural stability (anteroposterior, mediolateral and overall stability indices) was measured with the Biodex Stability System pre-intervention and post-intervention. RESULTS: The improvement in postural stability in the WBVT group was significantly greater than that in the CT group (p< or =0.05). The p values of the changing scores of open overall, open anteroposterior, open mediolateral, closed overall, closed anteroposterior and closed mediolateral stability indices were 0.002, 0.010, 0.0001, 0.001, 0.0001 and 0.046, respectively. In addition, there were significant differences in all averages of absolute angular error at 60 degrees and 30 degrees between the WBVT and CT groups in both knees (p = 0.001 in healthy knees and p = 0.001 and p = 0.0001 in reconstructed knees), apart from the healthy knees at the 30 degrees target position, which was not significant (p = 0.131). CONCLUSIONS: Whole body vibration training improved proprioception and balance in athletes with reconstructed ACL.

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 (K= 0.63, SE = 0.11, p < 0.001) for the assessment of wrist flexors spasticity in hemiplegic patients. 12 adult patients (7 women and 5 men) with first ever stroke resulting in hemiplegia with a mean age of 58.9 +/- 11.9 years (range, 37-73) were included in the validity study. The outcome measures were the MMAS for the clinical assessment of spasticity, and the HslopelMslope and the Hmax/Mmax ratio for the electrophysiological evaluation. The results showed an increase in mean rank of Hslp / Mslp in patients with a score of 1, 2 or 3 on the MMAS. However, the difference among the groups was not significant (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 large number of patients is suggested to clarify the outcome.

A randomized, single blind placebo controlled clinical trial on the effect of continuous ultrasound on low back pain.

Low back pain (LBP) is a very common problem in primary care and a major cause of disability. There is no evidence for the efficacy of therapeutic modalities such as ultrasound in LBP In a randomized, single blind placebo controlled clinical trial, we aimed to evaluate the effect of continuous ultrasound (US) in patients with non specific LBP Of the fifty eight patients recruited, 10 patients (8 women and 2 men) randomly allocated to ultrasound (n=5) or placebo controlled (n=5) groups. The patients were treated by either US or sham-US for ten sessions, three days per week, every other day. The outcome measures were Functional Rating Index (FRI), Hmax/Mmax ratio and range of motion (ROM), which were measured at baseline, after 5 treatment sessions and at the end of treatment. To analyze the data, The Mann Whitney U test and Wilcoxon Signed Rank test were used. After treatment, both US and placebo groups showed statistically significant decrease in FRI scores indicating improvement in functional ability (p = 0.042 and p = 0.043, respectively). The mean changes of FRI during the second five treatment sessions and after the end of treatment was significantly better in the US group than in the placebo group (p = 0.016 and p = 0.032, respectively). Before and after treatment, the mean H reflex latency and Hmax/Mmax ratio, right and left side were similar in the groups (p > 0.05), and no significant changes were observed in the treatment groups (p > 0.05). After treatment, the extension and lateral flexion range of motion significantly increased in the US group (p = 0.04), but the back movements in the placebo group did not show significant changes (p > 0.05). The present study supports the significant effect of US on LBP, and suggests that US may improve the functional ability of patients with non specific low back pain.

Is there any relationship between the Modified Ashworth Scale scores and alpha motoneuron excitability indicators?

The purpose of this study was to investigate the relationship between the modified Ashworth scale (MAS) scores and alpha motoneuron excitability indicators. Thirty-one post-stroke patients were assessed for this object. The main outcome measures were the MAS and electro physiologic assessments. The latter was performed using both conventional (Hmax/Mmax) and new (Hslope/Mslope) measures of spinal excitability. Data on thirty-one adult subjects with hemiplegia (twenty-five men and six women) were analysed. The soleus Hmax/Mmax ratio appeared to correlate directly with the MAS scores (r = 0.36; P < 0.05). Correlation between the MAS scores and either Hslope/Mslope ratio or H-reflex latency was not significant (P > 0.05). In seventeen patients whose H-reflex could be evoked bilaterally, spinal excitability indicators showed significant difference between the affected and non-affected sides (P < 0.05). Based on the results of this study, there is no relationship between the MAS scores and the preferred measure of alpha motoneuron excitability. This research suggests that the MAS could not distinguish between the reflexive and non-reflexive components of the hypertonicity in ankle plantar flexors.

The effect of transcutaneous electrical nerve stimulation on sympathetic skin response.

The aim of present study was to determine whether combination of transcutaneous electrical nerve stimulation (TENS) and acupuncture inhibits sympathetic nerve activity in healthy humans. Multiunit efferent postganglionic sympathetic activity was recorded with Toennies set. In this study, the aim was to obtain latency, amplitude and duration of sympathetic skin response (SSR) and skin temperature (ST) from both hands in 15 healthy subjects. Subjects randomly assigned and everybody participated in all the three groups [Control Group (CG), Acupuncture Group (AG) and Nerve Stimulation Group (NSG)]. TENS (2 Hz, 250 microsecond) was applied over the median nerve of the right elbow in NSG for 20 min, either, TENS was applied over (HE-7) point of the right hand in CG (TENS off) and AG (TENS on) for 20 min. SSR (lat, amp, dur) and ST data was recorded before TENS and for immediate, 5 min and 10 min post--TENS. ST was recorded in distal phalanx of index finger of both hands and SSR was recorded from both hands. TENS in CG did not affect ST and SSR following stimulation. TENS applied at AG and NSG caused a significant increase in ST (P = 0.001), significant increase in latency of SSR (P = 0.001), significant decrease in amplitude of SSR (P = 0.001) and no significant changes were observed in duration of SSR (P > 0.05). Then statistical analysis showed differences between both of groups (AG & NSG) for ST and SSR post--TENS. Transcutaneous electrical nerve stimulation inhibits sympathetic nerve activity in healthy humans.

The effects of electrical nerve stimulation of the lower extremity on H-reflex and F-wave parameters.

The main purpose of this study was to investigate the effects of electrical nerve stimulation on alpha motoneurons excitability. The electrophysiological parameters of H-reflex and F-wave were assessed for this object. These experiments was performed on ten non-athletic healthy men without neurologic disorders with mean age 25.6 years (SD 4.4) and three spastic hemiplegic patients with mean age 65.33 years (SD 6.32). In the experimental protocol, electrical stimulation (TENS) applied on common peroneal nerve with frequency 99 Hz and duration 0.25 ms for 30 minutes. H-reflex and F-wave of the soleus muscle were recorded in three stages sequenced immediately, 5 minutes and 10 minutes later on. The parameters such as amplitudes and latencies of H-reflex and F-wave were compared with the data of first record before stimulation. Finally, after 30 minutes application of TENS the following results were obtained: 1. The mean peak to peak amplitude of H-reflexes and F-waves were significantly decreased after application of TENS in normal subjects. (P < 0.05) 2. H/M ratios and F/M ratios were significantly decreased after application of TENS in normal subjects. (P < 0.05) 3. The mean latency of H-reflexes and F-waves were significantly increased after application of TENS in normal subjects. (P < 0.05) 4. In spastic patients, the mean peak to peak amplitude of H-reflexes and F-waves, H/M and F/M ratios were significantly decreased and the mean latencies of H-reflexes and F-waves were significantly increased after application of TENS. The reduction of amplitude of H-reflexes and F-waves, H/M and F/M ratios demonstrated reduction of spasticity in patients group. The above-mentioned parameters are parts of electrophysiological indicators about assessment of spasticity.