Neuromodulation in Professional Dancers

Study Overview
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Brief Summary
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Tendinopathy of the flexor hallucis longus (FHL), colloquially referred to as dancer's tendinitis, is a common condition in dancers and attributed to high demand on this muscle in positions of extreme ankle plantarflexion and metatarsophalangeal (MTP) flexion and extension. Tradicional conservative treatment includes rest from pain-inducing activities including pointe work and jumping, physical therapy a focusing on movilization of the joints of the first ray and subtalar joint, and antiinflamatory medications. Unfortunately, dancer frecuently do not follow recommendations to rest due to the competitive nature of the field. Those who do not respond to conservative treatment undergo more serious interventions including steroid injections or surgery, each with additional risks and recovery time. To develop experimental protocols aimed at prevention and nonsurgical interventions are needed. Therefore, the aim of this study was To investigate the effects of one shot of low-frequency percutaneous electrical nerve stimulation (PENS) vs. one shot of transcutaneous electrical nerve stimulation (TENS) in performance of the Flexor Hallucis Longus muscle in young dancers.

Official Title
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One-Shot Percutaneous Electrical Nerve Stimulation vs. Transcutaneous Electrical Nerve Stimulation for Performance Flexor Hallucis Longus Muscle in Professional Dancers

Conditions
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Rehabilitation, Sports Physical Therapy, Sport Performance, Dance

Intervention / Treatment
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* Other: PENS
* Other: TENS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female dancers Training at least twenty-five hours per week Pointe training at least five hours per week. Exclusion Criteria: They had sustained an injury to their stance limb in the past year preventing dancing for at least 1 day Personal Psychological Apprehension Scale (PPAS) score >37.5 Commonly accepted contraindications to invasive phsyiotherapist technique Any contraindications to needling per se. Commonly accepted contraindications to electrotherapy Epilepsy.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Percutaneous Electrial Stimulation (PES group).<br>This intervention consisted in the application of an asymmetric biphasic rectangular current. The subject lay prone with her feet outside the table. The FHL muscle was located at 50% of the distance between the fibular head and inferior border of the lateral malleolus on the posterior aspect of the fibular by ultrasound machine (cross-section) (Logiq, GE Healthcare, USA) and then, a needle (0.30mm x 0.40mm) was inserted, perpendicular to the surface of the skin, until the muscle belly. Prior to inserting a neddle, the underlying skin was cleaned with isopropyl alcohol. The intensity of the current was necessary to cause an exacerbated muscle contraction, during 1.5 min acording to the Valera and Minaya protocol´s. This intervention was performed once in each participant, on one leg only (stance limb), It's only once, it was not a treatment | Other: PENS<br>* This intervention consisted in the application of an asymmetric biphasic rectangular current of 150 microseconds and 10 Hz using a specifically developed medically certified device (Physio Invasive, Enraf Nonius, Prim, SPAIN). This is an invasive intervention by ultrasound and needles.<br>|
| Experimental: Transcutaneous Electrial Stimulation (TENS group)<br>This intervention consisted in the application of an asymmetric biphasic rectangular current. The subject lay prone with her feet outside the table. The FHL muscle was located at 50% of the distance between the fibular head and inferior border of the lateral malleolus on the posterior aspect of the fibular by ultrasound machine (cross-section) (Logiq, GE Healthcare, USA),and then, one self-adhesive electrode was placed on the back of the leg and the other on the sole of the foot. The intensity of the current was necessary to cause an exacerbated muscle contraction, during 1.5 min. This intervention was performed once in each participant, on one leg only (stance limb), It's only once, it was not a treatment | Other: TENS<br>* This intervention consisted in the application of an asymmetric biphasic rectangular current of 150 microseconds and 10 Hz using a specifically developed medically certified device (Physio Invasive, Enraf Nonius, Prim, SPAIN). This is a non-invasive intervention by self-adhesive electrodes.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in balance | Assessed by a single leg balance test | 1 day | 
| Change in muscular endurence, | Assessed by endurance test (heel raise repetitions). | 1 day | 
| Change in range of motion of first MTF joint | Assessed using goniometer. | 1 day |