Short-Latency Crossed Inhibitory Responses in the Human Soleus Muscle

2009 ◽  
Vol 102 (6) ◽  
pp. 3596-3605 ◽  
Author(s):  
Peter W. Stubbs ◽  
Natalie Mrachacz-Kersting
Keyword(s):  
Electrical Stimulation ◽  
Nerve Stimulation ◽  
Muscle Activation ◽  
Tibial Nerve ◽  
Voluntary Contraction ◽  
Short Latency ◽  
Afferent Feedback ◽  
Medial Plantar Nerve ◽  
Muscle Activation Patterns ◽  
Tibial Nerve Stimulation

Even though interlimb coordination is critical in bipedal locomotion, the role of muscle afferent mediated feedback is unknown. The aim of this study was to establish if ipsilateral muscle generated afferent feedback can influence contralateral muscle activation patterns in the human lower limb and to elucidate the mechanisms involved. The effect of ipsilateral tibial nerve stimulation on contralateral soleus (cSOL) responses were quantified. Three interventions were investigated, 1) electrical stimulation applied to the tibial nerve at stimulation intensities from 0 to 100% of maximal M-wave (M-max) with the cSOL contracted from 5 to 15% of maximal voluntary contraction (MVC) and 15 to 30% MVC, 2) ispsilateral tibial nerve stimulation at 75% M-max prior to, during, and following the application of ischemia to the ipsilateral thigh. 3) Electrical stimulation applied to the ipsilateral sural (SuN) and medial plantar nerves at stimulation intensities from 1 to 3 times perceptual threshold. A short-latency depression in the cSOL electromyogram (EMG; onset: 37–41 ms) was observed following ipsilateral tibial nerve stimulation. The magnitude of this depression increased ( P = 0.0005 and P = 0.000001) with increasing stimulus intensities. Ischemia delayed the time of the minimum of the cSOL depression ( P = 0.04). SuN and medial plantar nerve stimulation evoked a longer latency depression [average; 91.2 ms (SuN); 142 ms (medial plantar nerve)] and therefore do not contribute to the response. This is the first study to demonstrate a short-latency depression in the cSOL following ipsilateral tibial nerve stimulation. Due to its short latency, the response is spinally mediated. The involvement of crossed spinal interneurons receiving input from low-threshold muscle afferents is discussed.

scholarly journals Double-blind randomised controlled trial of percutaneous tibial nerve stimulation versus sham electrical stimulation in the treatment of faecal incontinence: CONtrol of Faecal Incontinence using Distal NeuromodulaTion (the CONFIDeNT trial)

2015 ◽  
Vol 19 (77) ◽  
pp. 1-164 ◽  
Author(s):  
Emma J Horrocks ◽  
Stephen A Bremner ◽  
Natasha Stevens ◽  
Christine Norton ◽  
Deborah Gilbert ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Faecal Incontinence ◽  
Nerve Stimulation ◽  
Primary Outcome ◽  
Tibial Nerve ◽  
Controlled Trial ◽  
Double Blind ◽  
Tibial Nerve Stimulation ◽  
Randomised Controlled

BackgroundFaecal incontinence (FI) is a common condition which is often under-reported. It is distressing for those suffering from it, impacting heavily on their quality of life. When conservative strategies fail, treatment options are limited. Percutaneous tibial nerve stimulation (PTNS) is a minimally invasive outpatient treatment, shown in preliminary case series to have significant effectiveness; however, no randomised controlled trial has been conducted.ObjectivesTo assess the effectiveness of PTNS compared with sham electrical stimulation in the treatment of patients with FI in whom initial conservative strategies have failed.DesignMulticentre, parallel-arm, double-blind randomised (1 : 1) controlled trial.SettingEighteen UK centres providing specialist nurse-led (or equivalent) treatment for pelvic floor disorders.ParticipantsParticipants aged > 18 years with FI who have failed conservative treatments and whose symptoms are sufficiently severe to merit further intervention.InterventionsPTNS was delivered via the Urgent®PC device (Uroplasty Limited, Manchester, UK), a hand-held pulse generator unit, with single-use leads and fine-needle electrodes. The needle was inserted near the tibial nerve on the right leg adhering to the manufacturer’s protocol (and specialist training). Treatment was for 30 minutes weekly for a duration of 12 treatments. Validated sham stimulation involved insertion of the Urgent PC needle subcutaneously at the same site with electrical stimulation delivered to the distal foot using transcutaneous electrical nerve stimulation.Main outcome measuresOutcome measures were assessed at baseline and 2 weeks following treatment. Clinical outcomes were derived from bowel diaries and validated, investigator-administered questionnaires. The primary outcome classified patients as responders or non-responders, with a responder defined as someone having achieved ≥ 50% reduction in weekly faecal incontinence episodes (FIEs).ResultsIn total, 227 patients were randomised from 373 screened: 115 received PTNS and 112 received sham stimulation. There were 12 trial withdrawals: seven from the PTNS arm and five from the sham arm. Missing data were multiply imputed. For the primary outcome, the proportion of patients achieving a ≥ 50% reduction in weekly FIEs was similar in both arms: 39 in the PTNS arm (38%) compared with 32 in the sham arm (31%) [odds ratio 1.28, 95% confidence interval (CI) 0.72 to 2.28;p = 0.396]. For the secondary outcomes, significantly greater decreases in weekly FIEs were observed in the PTNS arm than in the sham arm (beta –2.3, 95% CI –4.2 to –0.3;p = 0.02), comprising a reduction in urge FIEs (p = 0.02) rather than passive FIEs (p = 0.23). No significant differences were found in the St Mark’s Continence Score or any quality-of-life measures. No serious adverse events related to treatment were reported.ConclusionsPTNS did not show significant clinical benefit over sham electrical stimulation in the treatment of FI based on number of patients who received at least a 50% reduction in weekly FIE. It would be difficult to recommend this therapy for the patient population studied. Further research will concentrate on particular subgroups of patients, for example those with pure urge FI.Trial registrationCurrent Controlled Trials ISRCTN88559475.FundingThis project was funded by the NIHR Health Technology Assessment programme and will be published in full inHealth Technology Assessment; Vol. 19, No. 77. See the NIHR Journals Library website for further project information.

scholarly journals Cutaneous Reflexes During Human Gait: Electromyographic and Kinematic Responses to Electrical Stimulation

1997 ◽  
Vol 77 (6) ◽  
pp. 3311-3325 ◽  
Author(s):  
E. P. Zehr ◽  
T. Komiyama ◽  
R. B. Stein
Keyword(s):  
Electrical Stimulation ◽  
Nerve Stimulation ◽  
Tibial Nerve ◽  
Vastus Lateralis ◽  
Medial Gastrocnemius ◽  
Human Gait ◽  
Cutaneous Reflexes ◽  
Step Cycle ◽  
Tibial Nerve Stimulation ◽  
Corrective Response

Zehr, E. P., T. Komiyama, and R. B. Stein. Cutaneous reflexes during human gait: electromyographic and kinematic responses to electrical stimulation. J. Neurophysiol. 77: 3311–3325, 1997. The functions of ipsilateral cutaneous reflexes were studied with short trains of stimuli presented pseudorandomly to the superficial peroneal (SP) and tibial nerves during human gait. Electromyograms (EMGs) of tibialis anterior (TA), soleus, lateral and medial gastrocnemius, vastus lateralis (VL), and biceps femoris (BF) muscle were recorded, together with ankle and knee joint angles. Net reflex EMG responses were quantified in each of the 16 parts of the step cycle according to a recently developed technique. After SP nerve stimulation, TA muscle showed a significant suppression during swing phase that was highly correlated to ankle plantarflexion. BF and VL muscles were both excited throughout swing and significantly correlated to knee flexion during early swing. Tibial nerve stimulation caused dorsiflexion during late stance, but plantarflexion during late swing. We argue that SP nerve reflexes are indicative of a stumbling corrective response to nonnoxious electrical stimulation in humans. The correlated kinematic responses after tibial nerve stimulation may allow smooth movement of the swing leg so as to prevent tripping during swing and to assist placing and weight acceptance at the beginning of stance.

Sign in / Sign up

Export Citation Format

Share Document