H-reflex Parameters Research Articles

Association of H-reflex parameters and peroneal nerve conduction velocity with dynamic balance and agility in university athletes: a cross-sectional study

Abstract Athletic performance parameters encompass a wide range of physical, physiological, and biomechanical measures that are crucial for evaluating and optimising athletes’ capabilities. There are various intrinsic factors that can contribute to athletic skills, which subsequently impact overall performance. Thus, there is a need to explore significant intrinsic factors associated with athletic parameters, that can provide insights into the physiological mechanisms underlying performance. In this study, we examined the potential relationship of two such intrinsic factors, namely the H-reflex and the peroneal nerve conduction velocity, with athletic skills like dynamic balance and agility. Forty-five university-level athletes of all genders playing for different teams of Jamia Millia Islamia University, New Delhi, India were selected. All athletes underwent tibial H-reflex, peroneal NCV, mSEBT (for dynamic balance), and agility T-test evaluations. The Pearson correlation coefficient was calculated to evaluate the association of nerve function parameters (H-reflex and NCV) with athletic performance parameters (dynamic balance and agility). Results showed that H-reflex amplitude showed a significant negative correlation with both dynamic balance scores (Dominant Leg [DL]: r = −0.321 and ; Non-dominant leg [NDL]: r = −0.397 and ) and T-test scores (DL: r = −0.342; NDL: r = −0.321, ), respectively. The peroneal NCV was significantly positively correlated with dynamic balance (DL: r = 0.438 and ; NDL: r = 0.418 and ) and agility scores (DL: r = 0.639 and ; NDL: r = 0.641 and ) in athletes. In conclusion, significant associations were found between H-reflex and Peroneal nerve conduction velocity and key athletic performance parameters like dynamic balance and agility among university athletes. This implies that neural function is closely linked with athletic skills and performance. Registered in Clinical Trials Registry-India (CTRI) under registration number: REF/2023/11/075394.

Neurophysiological Assessment of H-Reflex Alterations in Compressive Radiculopathy.

This study aimed to investigate changes in the H-reflex recruitment curve in compressive radiculopathy, specifically assessing differences between symptomatic and asymptomatic limbs in patients with unilateral S1 radiculopathy through derived parameters. A total of 24 volunteers (15 male and 9 female, aged between 22 and 60 years) with confirmed nerve root compression in the L5/S1 segment participated. Nerve root compression was verified through clinical MRI examination and attributed to disc protrusion, spinal canal stenosis, or isthmic spondylolisthesis of L5/S1. Analysis revealed no difference in M-wave threshold intensity between symptomatic and non-symptomatic limbs. However, the H-reflex exhibited a trend toward increased threshold intensity in the symptomatic limb. Notably, a significant decrease in the slope of the H-reflex was observed on the symptomatic side, and the maximal H-reflex amplitude proved to be markedly different between the two limbs. The Hmax/Mmax ratio demonstrated a significant decrease in the symptomatic limb, indicating reduced effectiveness of signal translation. In conclusion, our findings emphasize the importance of H-reflex parameters in evaluating altered recruitment curves, offering valuable insights for neurological examinations. The observed differences in maximal values of M-wave, H-reflex, and their ratio in affected and unaffected limbs can enhance the diagnostic process for lumbosacral unilateral radiculopathy and contribute to a standardized approach in clinical assessments.

Efficiency evaluation of the Neuromidin in the treatment of pain of the patients with discogenic lumbosacral radiculopathy: results of a multicenter post-registration prospective open comparative trial

Evaluation of the effect of Neuromidine on the dynamics of pain syndrome in the treatment of patients with discogenic lumbosacral radiculopathy. Patients with a confirmed diagnosis of discogenic lumbosacral radiculopathy no more than one year old and moderate intensity of pain syndrome on a visual analog scale were included in the main group (OH, n=62, age - 53.1±15.6 yrs) and the comparison group (HS, n=40, age - 53.7±12.9 yrs). OG patients received Neuromidine (15 mg/1 mL 1 once a day IM for 10 days, then 20 mg 3 times a day for 8 weeks) in addition to the standard drug therapy, HS patients received only standard drug therapy. The duration of the study was 8 weeks. The degree of decrease in the intensity and dynamics of pain syndrome, activity and frequency of pain in the lumbar spine, changes in the level of physical activity, and the severity of emotional disorders were evaluated. The level of inflammatory markers in the blood and the dynamics of monosynaptic spinal H-reflex parameters were evaluated. Before the study, there were no statistically significant differences there were no results of clinical and laboratory-instrumental examination between groups. After 8 weeks, the reduction of pain by VAS in the main group was statistically significant in contrast to the comparison group (p=0.0001). In the main group there was a statistically significant increase in the mean cognitive impairment score (p=0.0029), as well as an improvement in psycho-emotional state with a significant decrease in GAD-7 (p=0.0002) and PHQ-9 (p=0.0096). After 8 weeks of therapy, IL-6 level in the main group was statistically significantly lower (p=0.0027) than in the comparison group. The results of H-reflex study revealed an increase in its amplitude and some shortening of latency at the end of Neuromidine therapy. The drug had no undesirable side effects and was well tolerated. Administration of Neuromidine 15 mg/1 ml once a day intramuscularly for 10 days followed by 20 mg 3 times a day for 8 weeks has an effective analgesic effect as adjuvant therapy in patients with discogenic lumbosacral radiculopathy. The inclusion of Neuromidine in the complex treatment of patients with pain syndrome in discogenic radiculopathy is superior in efficacy to standard drug therapy.

Electrophysiological Study in the Right Upper and Lower Limbs in Infants with Lumbosacral Meningomyelocele and in Normal Infants: A Case-control Study.

The study aimed to assess the electrophysiological parameters (Hofmann reflex [H-reflex] and motor nerve conduction velocity [MNCV]) on children's upper and lower limbs with lumbosacral meningomyelocele (MMC) and age-matched control to see the effect of the MMC on the cervical segment of the spinal cord. The present study was performed on infants with lumbosacral MMC. Twenty-five infants were examined with a mean age of 50 days of either sex. Out of them, 13 infants were in control and the remaining 12 were diagnosed with MMC. The H-reflex parameter and MNCV were recorded in these children's right upper and lower limbs. H-reflex was elicited in all the control group babies. In MMC, the H-reflex was elicited in the upper limbs. However, H-reflex was not elicited in the lower limbs of a few MMC babies. The upper limb's H-reflex parameters and conduction velocity were significantly higher than those corresponding lower limbs in control babies. In MMC, where the H-reflex was elicited, such differences in the lower and upper limbs were not observed. However, the values of MNCV in the upper limb (right median nerve) were significantly less, and the values of Hmax in the lower limb (soleus muscle) were significantly more in MMC babies than in the control group. The values of electrophysiological parameters were higher in the upper limbs as compared to the corresponding lower limbs in control. These values were not altered in the upper limbs than those corresponding lower limbs of MMC, suggesting that motor function development was impaired/delayed in the spinal segment cranial to MMC lesion, and motor impairment in MMC children is mostly a result of upper motor neuron dysfunction.

The effect of loss of foot sole sensitivity on H-reflex of triceps surae muscles and functional gait.

Objective: To investigate the effects of foot sole insensitivity on the outcomes of the triceps surae muscle H-reflex and functional gait. Material and Methods: People with peripheral neuropathy were recruited and divided into two groups: people with more (n = 13, 73.3 ± 4.3years old) or less (n = 10, 73.5 ± 5.3) sensitive tactile sensation. Their monofilament testing scores were 9.0 ± 1.5 (range: 7-10) and 2.3 ± 2.4 (range: 0-6) out of 10, respectively. H-reflex of the triceps surae muscles during quiet standing and their relationship with functional gait, 6min walking distance (6MWD), and timed-up-and-go duration (TUG), were compared between groups. Results: No significant difference was detected for H-reflex parameters between the groups. The less sensitive group showed reduced (p < .05) functional gait capacity compared to the other group, 38.4 ± 52.7 vs. 463.5 ± 47.6m for 6MWD, and 9.0 ± 1.5 vs. 7.2 ± 1.1s for TUG, respectively. A significant correlation (p < .05), worse functional gait related to greater H/M ratio, was observed in the less sensitive group, not the other group. Conclusion: Although there was no significant H-reflex difference between the groups, more pronounced tactile sensation degeneration affected functional gaits and their relationship with H-reflex.

Neurophysiologic evaluation of patients with cervical spondylotic myelopathy

BackgroundCervical spondylotic myelopathy (CSM) is a neurodegenerative disease caused by repetitive spinal cord damage that has resulted in significant clinical morbidity. The clinical evaluation of signs and symptoms, as well as neuroimaging and several neurophysiological tests, are used to make the diagnosis.ObjectivesTo investigate changes in the cutaneous silent period (CuSP), cortical silent period (CoSP), and H-reflex in CSM patients, and to correlate these tests with the Japanese Orthopedic Association (JOA) score and Nurick’s grading, as well as to determine the diagnostic value of each of them.MethodsTwenty patients (14 males and 6 females) with CSM were clinically diagnosed and documented by magnetic resonance imaging (MRI), and they were paired with another 20 healthy volunteers (13 males and 7 females) as a control group. CuSP, CoSP, and H-reflex tests were performed on both groups.ResultsIn CSM patients, CuSP latency and duration are substantially longer and shorter in CSM patients, respectively. The degree of changes in CuSP latency is well correlated with the severity of the disease. Further, CoSP duration is significantly shortened. The H-reflex parameters did not differ significantly between the patient and control groups.ConclusionThe shortened CoSP’s duration and the prolonged CuSP's latency suggest malfunction of the inhibitory and excitatory circuits in the spinal cord. The CuSP is more sensitive and specific than the CoSP in the diagnosis of a patient with CSM.

The Reduced Adaptability of H-Reflex Parameters to Postural Change With Deficiency of Foot Plantar Sensitivity.

Purpose: The project was to examine the influence of peripheral neuropathy (PN) severity on the relationship between Hoffmann-reflex (H-reflex) and postures. Methods: A total of 34 participants were recruited. H-reflex (H/M ratio and H-index) during prone, standing, and the heel-contact phase of walking was tested, along with foot sole sensitivity. Results: The participants were divided into three groups based on the severity of the foot sole sensitivity deficit: control, less (LA), and more (MA) affected with both feet 5.07 monofilament test scores ranging 10, 0–5, and 6–9, respectively. A significant group by the posture interaction was observed in the H/M ratio (F3.0, 41.9 = 2.904, p = 0.046, η p 2 = 0.172). In the control group, the H/M ratio of prone (22 ± 7%) was greater than that of the standing (13 ± 3%, p = 0.013) and heel-contact phase (10 ± 2%, p = 0.004). In the MA group, the H/M ratio of standing (13 ± 3%) was greater than that of the heel-contact phase (8 ± 2%, p = 0.011). The H-index was significantly different among groups (F2,28 = 5.711, p = 0.008, and η p 2 = 0.290). Post hoc analysis showed that the H-index of the control group (80.6 ± 11.3) was greater than that of the LA (69.8 ± 12.1, p = 0.021) and MA groups (62.0 ± 10.6, p = 0.003). Conclusion: In a non-PN population, the plantar sensory input plays an important role in maintaining standing postural control, while as for the PN population with foot sole sensitivity deficiency, type Ⅰ afferent fibers reflex loop (H-reflex) contributes more to the standing postural control. The H-index parameter is an excellent method to recognize the people with and without PN but not to distinguish the severity of PN with impaired foot sole sensitivity.

The effects of a single session of chiropractic care on strength, cortical drive, and spinal excitability in stroke patients

The objective of this study was to investigate whether a single session of chiropractic care could increase strength in weak plantar flexor muscles in chronic stroke patients. Maximum voluntary contractions (strength) of the plantar flexors, soleus evoked V-waves (cortical drive), and H-reflexes were recorded in 12 chronic stroke patients, with plantar flexor muscle weakness, using a randomized controlled crossover design. Outcomes were assessed pre and post a chiropractic care intervention and a passive movement control. Repeated measures ANOVA was used to asses within and between group differences. Significance was set at p < 0.05. Following the chiropractic care intervention there was a significant increase in strength (F (1,11) = 14.49, p = 0.002; avg 64.2 ± 77.7%) and V-wave/Mmax ratio (F(1,11) = 9.67, p = 0.009; avg 54.0 ± 65.2%) compared to the control intervention. There was a significant strength decrease of 26.4 ± 15.5% (p = 0.001) after the control intervention. There were no other significant differences. Plantar flexor muscle strength increased in chronic stroke patients after a single session of chiropractic care. An increase in V-wave amplitude combined with no significant changes in H-reflex parameters suggests this increased strength is likely modulated at a supraspinal level. Further research is required to investigate the longer term and potential functional effects of chiropractic care in stroke recovery.

H-reflex disinhibition by lumbar muscle inflammation in a mouse model of spinal cord injury

Inflammation is a common comorbidity in patients with traumatic spinal cord injury (SCI). Recent reports indicate that inflammation hinders functional recovery in animal models of SCI. However, the spinal mechanisms underlying this alteration are currently unknown. Considering that spinal plasticity is a therapeutic target in patients and animal models of SCI, these mechanisms remain to be clarified. Using injections of complete Freund’s adjuvant (CFA) in lumbar muscles as a model of persistent inflammation, the objective of this study was to assess the impact of inflammation on spinal reflex excitability after a complete midthoracic spinal transection in mice. To this end, the excitability of spinal reflexes was examined by measuring H-reflex frequency-dependent depression (FDD) on days 7, 14 and 28 following a complete spinal transection. H-reflex parameters were compared between spinal mice with CFA and control spinal mice. On day 7, lumbar muscle inflammation disinhibited the H-reflex, reflected by an attenuation of H-reflex FDD (p < 0.01), although this effect did not persist later on, either on day 14 or day 28. These results indicate that lumbar muscle inflammation alters spinal reflex excitability transiently in spinal mice. Considering that changes in spinal reflex excitability are associated with poor functional recovery after SCI, this implies that inflammation should be treated effectively to promote optimal recovery following SCI.

The role of transforaminal epidural steroid injections on H-reflex parameters in unilateral S1 radiculopathy

We aimed to evaluate whether transforaminal epidural steroid injections (TFESI) impact on H-reflex (HR) parameters in unilateral S1 radiculopathy, correlation between changes in HR parameters and treatment outcomes. A total of 34 patients with radicular low back pain, lumbar disc herniation and unilateral S1 root compression detected at L5-S1 level were included in this prospective study. The study was carried out in three stages. Before TFESI, patients were evaluated clinically (with motor and sensory examination, achilles reflex, fingertip-to-floor and straight leg raise test, numeric rating scale for pain, Oswestry Disability Index and Beck Depression Inventory) and radiologically by the first clinician. A second clinician performed nerve conduction studies and late responses. A third clinician carried out TFESI. 1st hour, 3rd week, 3rd month post-TFESI evaluations were carried out as they were before the treatment. In all follow-ups, there was a significant decrease in the HR latency, H-M interval in the affected side, and in difference between both sides in terms of HR latency after treatment, when compared to pre-treatment ( P < 0.05). On the 1st hour post-TFESI, HR was back to normal in 95.7% of 23 patients who had abnormal HR, and this recovery continued well into the 3rd month post-TFESI in 78.3%. No significant correlation was detected between HR changes and clinical recovery. Changes in HR latency were found to be correlated with the stage of nerve root compression. It was found that recovery in HR latency parameters can be achieved in addition to the clinical parameters after TFESI. The results are notable since they can shed light on future studies, which will investigate the role of HR in evaluating treatment outcomes and its predictive value. In cases where clinical and radiological findings are insufficient or controversial, changes in HR latency can be suggestive of the stage of nerve root compression.

Soleus H-Reflex and Its Modulation With Vibration in Idiopathic Toe Walkers and Typically Developing Children.

Idiopathic toe walking is a relatively common developmental condition often leading to secondary problems such as pain and muscle contractures in the lower extremities. The cause of idiopathic toe walking is unknown, which hinders the development of treatment strategies. To test whether children with idiopathic toe walking have functional alterations in their spinal motor circuits, we studied the properties of the soleus H-reflex and its modulation with vibration in 26 idiopathic toe walkers and 16 typically developing children. At the group level, the H-reflex properties did not differ, but at the individual level, in 7 of 25 idiopathic toe walkers, some of the H-reflex parameters fell out of normal limits of typically developing children. However, the H-reflex was suppressed by vibration to the Achilles tendon similarly in both the idiopathic toe walkers and typically developing children. In conclusion, idiopathic toe walking in some children can be associated with functional alterations in their spinal motor circuits.

SENSORY MECHANISM OF KINESIOLOGY TAPING CLINICAL EFFECT

The mechanisms of clinical effects of kinesiology taping (KT) remain unclear. Goals: to study the mechanisms of KT clinical effect and to compare the results with the present literature data. 23 subjects were examined for H-reflex parameters with KT classic application on m. soleus, without KT and with KT on the proximal and distal zones of the S1 dermatome. 6 subject were examined for motor response to transcranial magnetic stimulation from m. abductor pollicis brevis with/without KT application. A significant difference in the mean values of the H-reflex amplitudes was obtained for conditions with/without KT. No reliable differences in the amplitudes of the H-reflex for various types of KT applications were found (KT in the projection of the muscle, distal or proximal zone of the dermatome). A significant increase in the amplitude and the duration of motor responses from m. abductor pollicis brevis with KT application were revealed. The obtained results estimate the role of sensory activation mechanisms in the clinical effect of KT and contradict the existing hypotheses about a direct KT influence on a muscle.

77. Altered H-reflex following pulsed radiofrequency in patients with lumbosacral radicular pain

Pulsed radiofrequency (PRF) short-lasting bursts allow pain modulation with no tissue necrosis. Neurophysiological evaluation of PRF possible effects has not been described yet. Objective of this study was to investigate the effects of PRF on sensory nerve conduction and H-reflex in patients with lumbosacral radicular pain. We evaluated 23 patients with unilateral L5-S1 root pain who underwent PRF at the corresponding level of radicular symptoms. PRF was applied through a multifunctional electrode introduced via trans-sacral access for 240 s. at a frequency of 2 Hz, amplitude of 45 V and a tip temperature between 40 and 42 °C. Neurophysiological evaluation was performed with the patient lying on a fluoroscopy table in the prone position. Sural sensory action potentials (SAP) and soleus H-reflex were bilaterally evaluated. Outcome measures included variation of sural nerve conduction and H-reflex parameters pre-, post-treatment with PRF and after 30 days from the procedure. P values A significant decrease in H/M ratio was observed in the affected side of patients with paresthesia either post-treatment (p = 0.007) and at one month follow-up (p = 0.04). PRF might exert its clinical effects beyond DRG through an action on spinal inhibitory interneuronal circuitry.

What is the effect and mechanism of kinesiology tape on muscle activity?

ObjectiveThis study aimed to evaluate the effects of kinesiology tape, anesthesia, and kinesiology tape along with anesthesia, on motor neuron excitability. ParticipantsParticipants included 20 healthy men aged 20–35 years, who were examined over 5 sessions. InterventionThe five experimental sessions included: control without applying the kinesiology tape or Eutectic Mixture of Local Anesthetics (EMLA); treatment only with EMLA; only kinesiology tape application; only sham tape application; and treatment with kinesiology tape and EMLA. Main outcome measuresThe H-reflex recruitment curve of the soleus and lateral gastrocnemius was recorded by a blinded assessor in the 5 separate sessions randomly assigned with 48 h washout periods. The major H-reflex parameters include: the Hmax/Mmax ratio, the H-reflex threshold stimulation intensity (Hth), the intensity of maximum H-reflex (IntensityHmax), the H-reflex ascending slope (Hslp), and the H-reflex ascending slope fixed into the first three points (first Hslp). ResultsThe H-reflex parameters (H slope, first Hslp, Hth, and IntensityHmax) were facilitated by application of the kinesiology tape with and without EMLA; however, EMLA inhibited the H-reflex parameters (Hmax/Mmax ratio, Hslp, first Hslp, and Hth) in both the soleus and lateral gastrocnemius. The sham tape did not alter the H-reflex recruitment curve parameters. The statistical model revealed a significant difference between the kinesiology tape and the sham tape and control sessions, between kinesiology tape–EMLA and EMLA, and between kinesiology tape–EMLA and control session. ConclusionsResults suggest that the kinesiology tape facilitates the muscle activity and the underlying mechanism on the gastrosoleus motor neuron pool involves the cutaneous receptors.

The H-reflex modulation in lying and standing positions in young canoeists

Summary Study aim: to evaluate the differences in H-reflex parameters in lying and standing positions in canoeists. Material and methods: twenty seven male canoeists (age 17.2 ± 1.6 year, body mass 73.7 ± 7.6 kg, height 180.9 ± 6.1 cm, training experience 6.5 ± 3.6 years) participated in the study. None of the subjects had any history of neuromuscular disorders. The soleus H-reflex was examined in each subject twice: in lying and standing position. H-reflex was elicited by one-millisecond electrical stimulation of a posterior tibial nerve in the popliteal fossa. A recruitment curve for each subject was obtained by gradually increasing the stimulus intensity. Results: the results obtained in the present study showed statistically significant differences of the variables characterising effects of stimulations performed in lying and standing positions (F4,23 = 8.063; p &lt; 0.001). H/M ratio was 0.50 ± 0.25 and 0.64 ± 0.27 for lying and standing positions, respectively. Our results support previous findings. Conclusions: the lying position is recommended for measurements as more comfortable for subjects and providing a greater level of the elicited H-reflex.

The Effects of State Anxiety on Hoffman (H) Reflex Parameters in Female University Students

Background and Aim: Anxiety, as one of the most common and costly problems in Iran and all over the world, comprises both physical and mental disorders. Previous research has proposed that spinal reflex modulation may mediate anxiety-related changes in postural control. This study aimed to investigate if the H-reflex parameters are influenced by state anxiety. Materials and Methods: A group of 20 healthy female university students with a low anxiety score (lower than 42, based upon the Schpilberger’s questionnaire) were recruited in this study and the Hreflex of their Soleus muscle was recorded in four positions. The tested positions included the standard prone lying (the reference position), standing on level ground; and two stability threatening positions including standing on the center and at the edge of a one-meter height stool. The outcome measures were the latency, amplitude and the amplitude needed to record the reflex. Results: No significant differences were shown in the latency of the H-reflex among the four tested positions (p>0.05). In terms of the amplitude of the reflex, however, significant differences were found between all positions when compared to the reference position (prone lying) (p=0.001). There are significant differences among all four positions in amplitude needed to record the H-reflex (p=0.034), while the Bonferoni test revealed the significant difference only between the position of standing at the edge of the height relative to the standard prone lying position (p=0.041). Conclusion: The results of this study showed that any postural perturbation results in brain activities and affects more on the amplitudes rather than the latency of the H-reflex. These findings may be helpful in a better understanding of the standing balance in healthy people and people suffering from postural instabilities, fear of falling, elderly persons and also hemiplegic patients. Keywords: State Anxiety, H-Reflex, Stability threatening conditions

Extension traction treatment for patients with discogenic lumbosacral radiculopathy: a randomized controlled trial

Objective: To investigate the effects of lumbar extension traction in patients with unilateral lumbosacral radiculopathy due to L5–S1 disc herniation. Design: A randomized controlled study with six-month follow-up. Setting: University research laboratory. Subjects: Sixty-four patients with confirmed unilateral lumbosacral radiculopathy due to L5–S1 disc herniation and a lumbar lordotic angle less than 39°, randomly assigned to traction or control group. Interventions: The control group (n = 32) received hot packs and interferential therapy, whereas the traction group (n = 32) received lumbar extension traction in addition to hot packs and interferential therapy. Main outcome measures: Absolute rotatory angle, back and leg pain rating scale, Oswestry Disability Index, Modified Schober test, H-reflex (latency and amplitude) and intervertebral movements were measured for all patients three times (before treatment, after 10 weeks of treatment and at six-month follow-up). Results: There was a significant difference between the traction group and the control group adjusted to baseline values at 10 weeks post treatment with respect to: absolute rotatory angle (P < 0.001), Oswestry Disability Index (P = 0.002), back and leg pain (P = 0.009, P = 0.005), Modified Schober test (P = 0.002), latency and amplitude of H-reflex (P = 0.01, P < 0.001), intervertebral movements (P < 0.05). At six-month follow-up there were statistically significant differences between the study and control groups for all the previous variables (P < 0.05). Conclusion: The traction group receiving lumbar extension traction in addition to hot packs and interferential therapy had better effects than the control group with regard to pain, disability, H-reflex parameters and segmental intervertebral movements.

Spasticity and Electrophysiologic Changes after Extracorporeal Shock Wave Therapy on Gastrocnemius

ObjectiveTo evaluate the spasticity and electrophysiologic effects of applying extracorporeal shock wave therapy (ESWT) to the gastrocnemius by studying F wave and H-reflex.MethodTen healthy adults and 10 hemiplegic stroke patients with ankle plantarflexor spasticity received one session of ESWT on the medial head of the gastrocnemius. The modified Ashworth scale (MAS), tibial nerve conduction, F wave, and H-reflex results were measured before and immediately after the treatment. The Visual Analogue Scale (VAS) was used during ESWT to measure the side effects, such as pain.ResultsThere were no significant effects of ESWT on the conduction velocity, distal latency and amplitude of tibial nerve conduction, minimal latency of tibial nerve F wave, latency, or H-M ratio of H-reflex in either the healthy or stroke group. However, the MAS of plantarflexor was significantly reduced from 2.67±1.15 to 1.22±1.03 (p<0.05) after applying ESWT in the stroke group.ConclusionAfter applying ESWT on the gastrocnemius in stroke patients, the spasticity of the ankle plantarflexor was significantly improved, with no changes of F wave or H-reflex parameters. Further studies are needed to evaluate the mechanisms of the antispastic effect of ESWT.

Effect of prematurity and intrauterine growth restriction on H-reflex recovery cycle in neonates

Objective: The purpose of this work was to assess the effects of prematurity and intrauterine growth restriction on spinal cord synapses using H-reflex. Methods: 33 babies were investigated at birth. 14 were full term appropriate for gestational age (FT AGA), 10 were full term intrauterine growth restricted (FT IUGR) and 9 were preterm appropriate for gestational age (PT AGA). The maximum amplitude of H-reflex (Hmax), H-reflex latency (HRL), H/M ratio, H-reflex conduction velocity (HRCV), and H-reflex response to double stimuli (conditioning and test) for H-reflex recovery cycle (HRRC) were recorded in right lower limb (soleus muscle) in all the three groups. Results: Percentage recovery values of H-reflex were significantly higher in FT AGA and FT IUGR babies compared to PT AGA neonates for most of inter-stimulus intervals. No significant differences were observed in H-reflex parameters between FT AGA and FT IUGR groups, but HRL and HRCV were significantly affected in PT AGA group. Conclusions: Delayed H-reflex recovery in preterms may be due to a prolonged state of neurotransmitter delay in Ia terminals following initial activation by the conditioning stimuli. The cause of such prolonged depletion of neurotransmitters could be attributed to a poor neurotransmitter store in synaptic vesicles of spinal cord in preterm neonates.

The H reflex from the abductor brevis hallucis muscle in healthy subjects

In order to evaluate the clinical applicability of a neurophysiological technique, information is required about the effect of technical and subjective factors on the measured parameters, and whether these measures are reliable. The reliability of measurement of a given parameter is inversely related to the variability shown by a set of measurements of that parameter made on the same subject under similar conditions. Reliable measures are fundamental to the clinical utility of any technique. We evaluated the reliability using the intraclass correlation coefficient (ICC), and assessed both single-point and test-retest normal limits for H-reflex parameters of abductor brevis hallucis (ABH). The H reflex from the ABH muscle was recorded in 36 of 43 subjects, but could not be elicited in 7 of 11 subjects who were >60 years of age. The Hmax latency increased as height increased, whereas Hmax amplitude and Hmax/Mmax amplitude ratio decreased as age and height increased. The Hmax latency and Hmax/Mmax amplitude ratio, but not Hmax amplitude, proved to be reliable. The usefulness of the H reflex from ABH in the evaluation of S2 radiculopathies is described.