Gait Characteristics Following Stroke: A Prospective Crossover Study to Compare Ankle-Foot Orthosis with Functional Electrical Stimulation.

Background: Management of foot-drop following stroke can be addressed with ankle-foot orthosis (AFO) or functional electrical stimulation (FES) of the peroneal nerve. There is limited evidence regarding the efficacy of FES as a substitute for a conventional ankle-foot orthosis. Objective: The aim of this study was to compare efficacy of FES against AFO in management of foot-drop in patients following stroke. Materials and Methods: Twenty patients (ten per group) were enrolled in this prospective crossover trial. Group A patients received gait training with AFO during first week followed by training with FES during second week and vice-versa for group B. Outcome parameters following AFO/FES training included Ten-meter, Six-minute walk test and spatiotemporal gait parameters. Patient satisfaction level was assessed using feedback questionnaire. Friedman test and Wilcoxon signed-rank test were performed to compare outcomes between barefoot, AFO and FES. The P value < 0.05 was considered statistically significant. Results: Nineteen males and one female aged 45.5 ± 9.45 years were recruited. Statistically significant improvement was observed in Ten-meter and Six-minute walk tests, gait speed, Timed up and go test (TUG), stance-swing ratio and single-limb support among users of FES as compared to AFO and barefoot. There was no statistical difference observed in other gait parameters. Physiological cost index (PCI) showed trend in improvement among FES users. Patient satisfaction scores were higher for FES users. Conclusions: Quantitative and qualitative results were in favour of FES as compared to AFO and barefoot suggesting that FES can be a potential orthotic intervention in hemiplegic patients.

Musculoskeletal ultrasonography combined with electromyography in the diagnosis of massage-inducted lateral plantar nerve injury: A case report.

INTRODUCTION: It is well known that foot massage is a very prevalent stress relief method in China. Literatures have reported various massage-inducted peripheral nerve injuries. However, massage-inducted lateral plantar nerve (LPN) injury is very rare. Here, we represent an unusual case of massage-inducted LPN damage, and we also report the diagnostic method of this patient using musculoskeletal ultrasonography combined with electromyography (EMG). PATIENT CONCERNS: A 21-year-old woman presented symptoms of redness, swelling, pain and numbness in the medial right ankle joint for 2 days. DIAGNOSIS: The results of musculoskeletal ultrasonography and EMG provide great help for doctors to make accurate diagnosis. The patient was eventually diagnosed with LPN injury. INTERVENTIONS: No further foot massage was allowed. Vitamin B12 was taken orally for 2 months. Conservative therapy, including electrical stimulation therapy and infrared therapy, was conducted. Besides, active rehabilitation training was also performed. OUTCOMES: The discomfort symptoms were relieved significantly after 2 months conservative treatment. Clinical symptoms and EMG examination illustrated satisfactory result during follow up time. CONCLUSION: The report showed that the masseur should be very careful when doing foot massage to prevent nerve damage. Besides, musculoskeletal ultrasonography combined with EMG can provide important evidence for accurate and effective diagnosis of LPN injury.

Effects of posture and coactivation on corticomotor excitability of ankle muscles.

BACKGROUND: The use of transcranial magnetic stimulation (TMS) to evaluate corticomotor excitability of lower limb (LL) muscles can provide insights about neuroplasticity mechanisms underlying LL rehabilitation. However, to date, a majority of TMS studies have focused on upper limb muscles. Posture-related activation is an important under-investigated factor influencing corticomotor excitability of LL muscles. OBJECTIVE: The purpose of this study was to evaluate effects of posture and background activation on corticomotor excitability of ankle muscles. METHODS: Fourteen young neurologically-unimpaired participants (26.1±4.1 years) completed the study. TMS-evoked motor evoked potentials (MEPs) were recorded from the tibialis anterior (TA) and soleus during 4 conditions - standing, standing coactivation, sitting, and sitting coactivation. TA and soleus MEP amplitudes were compared during: (1) standing versus sitting;(2) standing coactivation (standing while activating both TA and soleus) versus sitting coactivation; and (3) standing coactivation versus standing. For each comparison, background EMG for TA and soleus were matched. Trial-to-trial coefficient of variation of MEP amplitude and coil-positioning errors were additional dependent variables. RESULTS: No differences were observed in TA or soleus MEP amplitudes during standing versus sitting. Compared to sitting coactivation, larger MEPs were observed during standing coactivation for soleus but not TA. Compared to standing, the standing coactivation task demonstrated larger MEPs and reduced trial-to-trial MEP variability. CONCLUSION: Our findings suggest that incorporation of measurements in standing in future TMS studies may provide novel insights into neural circuits controlling LL muscles. Standing and standing coactivation tasks may be beneficial for obtaining functionally-relevant neuroplasticity assessments of LL musculature.

The Effect of Passive Movement for Paretic Ankle-Foot and Brain Activity in Post-Stroke Patients.

BACKGROUND: This study aims at investigating the short-term efficacy of the continuous passive motion (CPM) device developed for the therapy of ankle-foot paresis and to investigate by fMRI the blood oxygen level-dependent responses (BOLD) during ankle passive movement (PM). METHODS: Sixty-four stroke patients were investigated. Patients were assigned into 2 groups: 49 patients received both 15 min manual and 30 min device therapy (M + D), while the other group (n = 15) received only 15 min manual therapy (M). A third group of stroke patients (n = 12) was investigated by fMRI before and immediately after 30 min CPM device therapy. There was no direct relation between the fMRI group and the other 2 groups. All subjects were assessed using the Modified Ashworth Scale (MAS) and a goniometer. RESULTS: Mean MAS decreased, the ankle's mean plantar flexion and dorsiflexion passive range of motion (PROM) increased and the equinovalgus improved significantly in the M + D group. In the fMRI group, the PM of the paretic ankle increased BOLD responses; this was observed in the contralateral pre- and postcentral gyrus, superior temporal gyrus, central opercular cortex, and in the ipsilateral postcentral gyrus, frontal operculum cortex and cerebellum. CONCLUSION: Manual therapy with CPM device therapy improved the ankle PROM, equinovalgus and severity of spasticity. The ankle PM increased ipsi- and contralateral cortical activation.

Reducing The Cost of Transport and Increasing Walking Distance After Stroke: A Randomized Controlled Trial on Fast Locomotor Training Combined With Functional Electrical Stimulation.

Background Neurorehabilitation efforts have been limited in their ability to restore walking function after stroke. Recent work has demonstrated proof-of-concept for a functional electrical stimulation (FES)-based combination therapy designed to improve poststroke walking by targeting deficits in paretic propulsion. Objectives To determine the effects on the energy cost of walking (EC) and long-distance walking ability of locomotor training that combines fast walking with FES to the paretic ankle musculature (FastFES). Methods Fifty participants >6 months poststroke were randomized to 12 weeks of gait training at self-selected speeds (SS), fast speeds (Fast), or FastFES. Participants' 6-minute walk test (6MWT) distance and EC at comfortable (EC-CWS) and fast (EC-Fast) walking speeds were measured pretraining, posttraining, and at a 3-month follow-up. A reduction in EC-CWS, independent of changes in speed, was the primary outcome. Group differences in the number of 6MWT responders and moderation by baseline speed were also evaluated. Results When compared with SS and Fast, FastFES produced larger reductions in EC (Ps ≤.03). FastFES produced reductions of 24% and 19% in EC-CWS and EC-Fast (Ps <.001), respectively, whereas neither Fast nor SS influenced EC. Between-group 6MWT differences were not observed; however, 73% of FastFES and 68% of Fast participants were responders, in contrast to 35% of SS participants. Conclusions Combining fast locomotor training with FES is an effective approach to reducing the high EC of persons poststroke. Surprisingly, differences in 6MWT gains were not observed between groups. Closer inspection of the 6MWT and EC relationship and elucidation of how reduced EC may influence walking-related disability is warranted.

Ultrasound-Guided Ankle Blocks: A Review of Current Practices.

Ankle blocks are routinely indicated for surgical anesthesia and postoperative analgesia of procedures involving the foot. Traditionally, ankle blocks have been performed by relying on landmark identification of nerves. The literature regarding the performance and efficacy of ankle blocks is inconsistent. This can be attributed to several variables, such as provider technique, differences in patient populations, and the type and volume of local anesthetics administered. As with other peripheral nerve blocks originally performed using landmark technique, ultrasound imaging is now being incorporated into these procedures. Ultrasound guidance provides the anesthetist with several advantages over landmark techniques. The ability to identify peripheral nerves, view needle movements in real-time, and observe the spread of local anesthetic has been shown to result in greater block efficacy, even with reduced volumes of local anesthetic. Additionally, ultrasound imaging gives the provider the option to perform regional anesthesia in specific patient populations not considered possible when using landmark technique. Despite the limited literature on ultrasound-guided ankle blocks, outcome metrics seem to be consistent with those of other peripheral nerve blocks performed using this technology.

Noninvasive neurostimulation in chronic stroke: a double-blind randomized sham-controlled testing of clinical and corticomotor effects.

BACKGROUND: Repetitive peripheral magnetic stimulation (RPMS) is a painless and noninvasive method to produce afferents via the depolarization of the peripheral nervous system. A few studies tested RPMS after-effects on cerebral plasticity and motor recovery in stroke individuals, but evidences remain limited. OBJECTIVES: This study aimed to explore whether RPMS could mediate improvements in corticomotor and clinical outcomes associated with ankle impairments in chronic stroke. METHODS: Eighteen subjects with chronic stroke were randomly allocated to RPMS or sham group and compared to 14 healthy subjects. Stimulation was applied over the paretic tibialis anterior (TA). Ankle impairments on the paretic side and ipsilesional TA cortical motor representation were tested clinically and by transcranial magnetic stimulation (TMS), respectively. RESULTS: In the RPMS group, ankle dorsiflexion mobility and maximal isometric strength increased and resistance to plantar flexor stretch decreased. The magnitude of change seemed to be related to cortical and corticospinal integrity. Sham stimulation yielded no effect. Changes in TMS outcome and their relationships with clinical improvements were limited. CONCLUSIONS: RPMS improved ankle impairments in chronic stroke likely by a dynamic influence of sensory inputs on synaptic plasticity. The neurophysiological mechanisms potentially underlying the clinical effects are unclear. More studies are warranted to test the spinal and hemispheric changes responsible for the clinical improvements with emphasis on circuits spared by the lesion.

Essential regional nerve blocks for the dermatologist: Part 2.

Following on from Part 1 of the series (regional nerve blocks for the face and scalp), we guide the clinician through the anatomy and cutaneous innervation of the digits, wrist and ankle, providing a practical step-by-step guide to regional nerve blockade of these areas.

The effects of peroneal nerve functional electrical stimulation versus ankle-foot orthosis in patients with chronic stroke: a randomized controlled trial.

BACKGROUND: Evidence supports peroneal nerve functional electrical stimulation (FES) as an effective alternative to ankle-foot orthoses (AFO) for treatment of foot drop poststroke, but few randomized controlled comparisons exist. OBJECTIVE: To compare changes in gait and quality of life (QoL) between FES and an AFO in individuals with foot drop poststroke. METHODS: In a multicenter randomized controlled trial (ClinicalTrials.gov #NCT01087957) with unblinded outcome assessments, 495 Medicare-eligible individuals at least 6 months poststroke wore FES or an AFO for 6 months. Primary endpoints: 10-Meter Walk Test (10MWT), a composite of the Mobility, Activities of Daily Living/Instrumental Activities of Daily Living, and Social Participation subscores on the Stroke Impact Scale (SIS), and device-related serious adverse event rate. Secondary endpoints: 6-Minute Walk Test, GaitRite Functional Ambulation Profile (FAP), Modified Emory Functional Ambulation Profile (mEFAP), Berg Balance Scale (BBS), Timed Up and Go, individual SIS domains, and Stroke-Specific Quality of Life measures. Multiply imputed intention-to-treat analyses were used with primary endpoints tested for noninferiority and secondary endpoints tested for superiority. RESULTS: A total of 399 subjects completed the study. FES proved noninferior to the AFO for all primary endpoints. Both the FES and AFO groups improved significantly on the 10MWT. Within the FES group, significant improvements were found for SIS composite score, total mFEAP score, individual Floor and Obstacle course time scores of the mEFAP, FAP, and BBS, but again, no between-group differences were found. CONCLUSIONS: Use of FES is equivalent to the AFO. Further studies should examine whether FES enables better performance in tasks involving functional mobility, activities of daily living, and balance.

Effect of a foot-drop stimulator and ankle-foot orthosis on walking performance after stroke: a multicenter randomized controlled trial.

BACKGROUND: Studies have demonstrated the efficacy of functional electrical stimulation in the management of foot drop after stroke. OBJECTIVE: To compare changes in walking performance with the WalkAide (WA) foot-drop stimulator and a conventional ankle-foot orthosis (AFO). METHODS: Individuals with stroke within the previous 12 months and residual foot drop were enrolled in a multicenter, randomized controlled, crossover trial. Subjects were assigned to 1 of 3 parallel arms for 12 weeks (6 weeks/device): arm 1 (WA-AFO), n = 38; arm 2 (AFO-WA), n = 31; arm 3 (AFO-AFO), n = 24. Primary outcomes were walking speed and Physiological Cost Index for the Figure-of-8 walking test. Secondary measures included 10-m walking speed and perceived safety during this test, general mobility, and device preference for arms 1 and 2 for continued use. Walking tests were performed with (On) and without a device (Off) at 0, 3, 6, 9, and 12 weeks. RESULTS: Both WA and AFO had significant orthotic (On-Off difference), therapeutic (change over time when Off), and combined (change over time On vs baseline Off) effects on walking speed. An AFO also had a significant orthotic effect on Physiological Cost Index. The WA had a higher, but not significantly different therapeutic effect on speed than an AFO, whereas an AFO had a greater orthotic effect than the WA (significant at 12 weeks). Combined effects on speed after 6 weeks did not differ between devices. Users felt as safe with the WA as with an AFO, but significantly more users preferred the WA. CONCLUSIONS: Both devices produce equivalent functional gains.

Cortical output to fast and slow muscles of the ankle in the rhesus macaque.

The cortical control of fast and slow muscles of the ankle has been the subject of numerous reports yielding conflicting results. Although it is generally agreed that cortical stimulation yields short latency facilitation of fast muscles, the effects on the slow muscle, soleus, remain controversial. Some studies have shown predominant facilitation of soleus from the cortex while others have provided evidence of differential control in which soleus is predominantly inhibited from the cortex. The objective of this study was to investigate the cortical control of fast and slow muscles of the ankle using stimulus triggered averaging (StTA) of EMG activity, which is a sensitive method of detecting output effects on muscle activity. This method also has relatively high spatial resolution and can be applied in awake, behaving subjects. Two rhesus macaques were trained to perform a hindlimb push-pull task. Stimulus triggered averages (StTAs) of EMG activity (15, 30, and 60 µA at 15 Hz) were computed for four muscles of the ankle [tibialis anterior (TA), medial gastrocnemius (MG), lateral gastrocnemius (LG), and soleus] as the monkeys performed the task. Poststimulus facilitation (PStF) was observed in both the fast muscles (TA, MG, and LG) as well as the slow muscle (soleus) and was as common and as strong in soleus as in the fast muscles. However, while poststimulus suppression (PStS) was observed in all muscles, it was more common in the slow muscle compared to the fast muscles and was as common as facilitation at low stimulus intensities. Overall, our results demonstrate that cortical facilitation of soleus has an organization that is very similar to that of the fast ankle muscles. However, cortical inhibition is organized differently allowing for more prominent suppression of soleus motoneurons.

Levodopa changes brain motor network function during ankle movements in Parkinson's disease.

Bradykinesia-the cardinal symptom in Parkinson's disease (PD)-affects both upper and lower limbs. While several functional imaging studies investigated the impact of levodopa on movement-related neural activity in Parkinson's disease during upper limb movements, analogue studies on lower limb movements are rare. We studied 20 patients with PD (mean age 66.8 ± 7.2 years) after at least 12 h drug withdrawal (OFF-state) and a second time approximately 40 min after oral administration of 200 mg levodopa (ON-state) behaviourally and by functional magnetic resonance imaging (fMRI) at 3 T during externally cued active ankle movements of the more affected foot at fixed rate. Results were compared with that obtained in ten healthy controls (HC) to separate pure pharmacological from disease-related levodopa-induced effects and to allow for interaction analyses. Behaviourally, all patients improved by at least 20 % regarding the motor score of the Unified Parkinson's disease rating scale after levodopa-challenge (mean scores OFF-state: 38.4 ± 10.1; ON-state: 25.5 ± 8.1). On fMRI, levodopa application elicited increased activity in subcortical structures (contralateral putamen and thalamus) in the patients. In contrast, no significant levodopa-induced activation changes were found in HC. The interaction between "PD/HC group factor" and "levodopa OFF/ON" did not show significant results. Given the levodopa-induced activation increases in the putamen and thalamus with unilateral ankle movements in patients with PD but not in HC, we speculate that these regions show the most prominent response to levodopa within the cortico-subcortical motor-circuit in the context of nigrostriatal dysfunction.

Effect of peroneal electrical stimulation versus an ankle-foot orthosis on obstacle avoidance ability in people with stroke-related foot drop.

BACKGROUND: Walking ability of people with foot drop in the chronic phase after stroke is better with functional electrical stimulation (FES) of the peroneal nerve than without an orthotic device. However, the literature is not conclusive on whether peroneal FES also is better than an ankle-foot orthosis (AFO) in this regard. OBJECTIVE: This study aimed to identify potential benefits of peroneal FES over an AFO with respect to the ability to negotiate a sudden obstacle. DESIGN: The study design was a within-subject comparison between FES and AFO using repeated measures. METHODS: Twenty-four community-dwelling people with stroke (mean age=52.6 years, SD=12.7) who regularly used a polypropylene AFO were fitted with a transcutaneous FES device. The participants' obstacle avoidance ability was tested after 2 and 8 weeks. They had to avoid 30 obstacles that were suddenly dropped on a treadmill in front of the affected leg while walking with either FES or an AFO. The obstacle avoidance success rates were determined. RESULTS: Success rates were higher with FES than with an AFO, especially after adjustment for individual leg muscle strength. Participants with relatively low muscle strength (Motricity Index score <64) were most likely to benefit from FES regarding obstacle avoidance ability. LIMITATION: Further work is needed to determine whether the results may be generalized to other groups of people with stroke. CONCLUSIONS: Peroneal FES seems to be superior to an AFO with regard to obstacle avoidance ability in community-dwelling people with stroke. The observed gains in obstacle avoidance ability appear to be clinically most relevant in the people with relatively low leg muscle strength.

Non-invasive brain stimulation enhances fine motor control of the hemiparetic ankle: implications for rehabilitation.

We set out to answer two questions with this study: 1. Can stroke patients improve voluntary control of their paretic ankle by practising a visuo-motor ankle-tracking task? 2. Are practice effects enhanced with non-invasive brain stimulation? A carefully selected sample of chronic stroke patients able to perform the experimental task attended three data collection sessions. Facilitatory transcranial direct current stimulation (tDCS) was applied in a random order over the lower limb primary motor cortex of the lesioned hemisphere or the non-lesioned hemisphere or sham stimulation was delivered over the lesioned hemisphere. In each session, tDCS was applied as patients practiced tracking a sinusoidal waveform for 15 min using dorsiflexion-plantarflexion movements of their paretic ankle. The difference in tracking error prior to, and after, the 15 min of practice was calculated. A practice effect was revealed following sham stimulation, and this effect was enhanced with tDCS applied over the lesioned hemisphere. The practice effect observed following sham stimulation was eliminated by tDCS applied over the non-lesioned hemisphere. The study provides the first evidence that non-invasive brain stimulation applied to the lesioned motor cortex of moderate- to well-recovered stroke patients enhances voluntary control of the paretic ankle. The results provide a basis for examining whether this enhanced ankle control can be induced in patients with greater impairments and whether enhanced control of a single or multiple lower limb joints improves hemiparetic gait patterns.

Effects of quadriceps and anterior tibial muscles electrical stimulation on the feet and ankles of patients with spinal cord injuries.

STUDY DESIGN: Controlled clinical test. OBJECTIVES: The purpose of this study was to assess the effects of quadriceps and anterior tibial muscles electrical stimulation on the feet and ankles of patients with spinal cord injuries and to compare them with able-bodied individuals and a group of patients who did not undergo neuromuscular electrical stimulation (NMES). SETTING: This study was conducted at the Hospital das Clínicas of Unicamp, Campinas, São Paulo, Brazil. METHODS: Between January and April 2008, 30 patients at the spinal cord injury ambulatory clinic who underwent NMES (group A) were submitted to a clinical and radiographic assessment of their feet and ankles and compared with a spinal cord injury group (group B) who did not undergo NMES and a group of able-bodied individuals (group C). The Kruskal-Wallis test was used to compare all the three groups, and between-group differences (P<0.05) were investigated with the Mann-Whitney test. RESULTS: The mean mobility of the midfoot and ankle subtalar joint was significantly higher in group C than in groups A and B. Differences in the mean measurements of the profiles of the talocalcaneal and the talus-first metatarsal angles were statistically significant for group A vs the other groups (P=0.0020, 0.0024, respectively). Foot deformities were found in groups including claw toes and flat feet (group A) and grade I ulcers on the lateral malleolus and calcaneus (group B). CONCLUSION: Partial-load NMES maintains the feet and ankles in a planted and adequate walking position in patients with spinal cord injuries, a favorable result of new technologies that allows these patients to reacquire independent walking capacity.

Immediate effect of transcutaneous electrical nerve stimulation on spasticity in patients with spinal cord injury.

OBJECTIVE: To investigate the immediate effect of transcutaneous electrical nerve stimulation (TENS) on spasticity in patients with spinal cord injury. DESIGN: Randomized controlled trial. SETTING: Extended rehabilitation centre. SUBJECTS AND INTERVENTION: Eighteen subjects with spinal cord injury and symptoms of spasticity over lower limbs were randomly assigned to receive either 60 minutes of active TENS (0.25 ms, 100 Hz, 15 mA) or 60 minutes of placebo non-electrically stimulated TENS over the common peroneal nerve. OUTCOME MEASURES: Composite Spasticity Score was used to assess the spasticity level of ankle plantar flexors immediately before and after TENS application. Composite Spasticity Score consisted of Achilles tendon jerks, resistance to full-range passive ankle dorsiflexion and ankle clonus. Between-group statistical differences of reduction of Composite Spasticity Score, Achilles tendon jerks, resistance to full-range passive ankle dorsiflexion and ankle clonus were calculated using the Mann-Whitney test. Within-group statistical differences of Composite Spasticity Score, Achilles tendon jerks, resistance to full-range passive ankle dorsiflexion and ankle clonus were calculated using the Wilcoxon signed ranks test. RESULTS: Significant reductions were shown in Composite Spasticity Score by 29.5% (p = 0.017), resistance to full-range passive ankle dorsiflexion by 31.0% (p = 0.024) and ankle clonus by 29.6% (p = 0.023) in the TENS group but these reductions were not found in the placebo TENS group. The between-group differences of both Composite Spasticity Score and resistance to full-range passive ankle dorsiflexion were significant (p = 0.027 and p = 0.024, respectively). CONCLUSION: This study showed that a single session of TENS could immediately reduce spasticity.

Heightened flexor withdrawal response in individuals with knee osteoarthritis is modulated by joint compression and joint mobilization.

UNLABELLED: Patients with chronic pain often present with hyperalgesia, possibly due to hyperexcitability of nociceptive pathways. The aim of the present study was to investigate alterations in flexor withdrawal reflex (FWR) excitability in individuals with knee osteoarthritis (OA) and the potential effect of specific physical inputs or therapeutic interventions (ie, joint compression and mobilization) on these behaviors. Ten subjects with and 10 without knee OA (age 45-75) were recruited. The FWR was examined utilizing suprathreshold, noxious electrocutaneous stimuli applied at the medial foot. Surface electromyographic (EMG) was recorded from the tibialis anterior (TA) and biceps femoris (BF), and peak joint torques recorded at the hip, knee, and ankle. FWR threshold was ascertained and responses at 2x threshold recorded after the following conditions: a maximal, volitional, joint-compression task, a sham hands-on intervention, and a Grade III oscillatory joint-mobilization intervention. A decreased threshold-to-flexor withdrawal response was found in the OA vs control group (P < .01). EMG and joint-torque FWR responses were further augmented in the OA group following the maximal joint-compression task (P < .05), yet remained unchanged or diminished in controls. Joint mobilization, but not sham intervention, reduced reflex responses significantly, although primarily by decreasing BF activity and knee torques (P < .05). PERSPECTIVE: Application of specific physical inputs to individuals with knee OA similar to those encountered during activity of daily living or during therapeutic interventions appear to modulate involuntary, nociceptive reflex responses. Routine weight-bearing activities such as walking may potentially enhance heightened FWR responses, while joint mobilization, a commonly used clinical intervention, may diminish reflex excitability.

The startle reaction to somatosensory inputs: different response pattern to stimuli of upper and lower limbs.

Unexpected sensory inputs can generate a patterned startle reaction, aimed at protection and defense. Experimentally, it is usually triggered by auditory stimuli while the startle reaction to somatosensory inputs (SSS) has not received much attention so far. This may be in part due to the fact that somatosensory inputs inevitably cause local reactions, such as short and long latency reflexes and withdrawal reactions, which could interfere with recognition of the startle-related activity. Therefore, we have undertaken a study aimed at separating the SSS from other responses by exploring the responses that are common to somatosensory stimuli applied to different sites and examining the inhibitory effects of prepulse stimuli. In 13 healthy naive subjects, we applied electrical stimuli to the median nerve at the wrist (MW) or the posterior tibial nerve at the ankle (PT) and recorded from orbicularis oculi (OOC), masseter (MAS), sternocleidomastoid (SCM) and representative muscles of the limbs being stimulated (flexor carpi radialis for MW and tibialis anterior for PT). In random trials, we also applied prepulse stimuli, either a low-intensity auditory stimulus or low-intensity electrical stimuli, 100 ms before the SSS-eliciting stimulus. The pattern of SSS was different for upper and lower limb stimuli. While stimuli applied to MW induced a prominent reaction of the OOC, at a mean latency of 61.1 ms (SD = 16.3 ms), followed by the SCM at a mean latency of 83.3 ms (SD = 28.6 ms), those applied to the PT caused a small or absent response in the OOC and a consistent response of the SCM at a mean latency of 89.7 ms (SD = 30.1 ms). Prepulse stimuli effectively inhibited the responses of facial and neck muscles but only partially those of the wrist flexors to MW or the tibialis anterior to PT. Our results indicate that, although there are common neck and facial muscle reactions to somatosensory stimuli applied to upper and lower limbs, the pattern of the SSS differs according to the source of the input. Prepulse inhibition is more effective on the responses of neck and facial muscles than on the responses of limb muscles to somatosensory stimuli. These results could help in distinguishing between withdrawal and SSS reactions.

Stoller afferent nerve stimulation in woman with therapy resistant over active bladder; a 1-year follow up.

AIM: In this prospective observational study, we investigated the efficacy of Stoller afferent nerve stimulation (SANS) in subjects with overactive bladder who failed anticholinergic treatment. METHODS: Thirty-five subjects with overactive bladder who failed therapy with oxybutynin participated in this study. Treatment (n = 35) was given once a week for 30 minutes for overall 10 weeks. In treatment, SANS device (Urosurge) was used. Subjects were assessed with 3-day voiding diary, SEAPI quality of life questionnaires and cystometry before therapy after completion of therapy and at one-year follow-up. RESULTS: In 54% (n = 19) of subjects complete recovery was obtained after treatment. Urgency and SEAPI were reduced significantly whereas urine volume increased significantly (p < 0.01). Complete recovery was maintained in eight of the 19 subjects at one year. CONCLUSIONS: SANS treatment has a short-term positive effect in patients with resistant overactive bladder. However, it was also established that efficacy was maintained at 1 year in only 23% of subjects.