Neuromodulation in Chronic Ankle Instability

Ankle sprain is a common injury. Around 712,000 sprains occur every day in the world. It is estimated that they account for 45% of sports injuries, being the second part of the body that is most frequently injured in sports. Of the patients who suffer this injury, around 70% will develop chronic ankle instability, a situation that can cause residual pain, recurrent sprains, a feeling of lack of stability and decreased physical activity. Two entities can be included in chronic ankle instability: mechanical instability, which involves movement of the joint beyond its physiological limit, and functional instability, which includes proprioceptive dysfunction, impaired neuromuscular control, postural control, and strength deficits. Currently, the conservative treatment of these patients consists of neuromuscular training through the use of dynamic balance platforms, taping, joint mobilization, dry needling, and the use of plantar supports, balance training being the one that has shown the best result. Ultrasound-guided percutaneous neuromodulation (PNM) is a recently used technique in the field of invasive physiotherapy that consists of applying a square wave biphasic electrical current through an acupuncture needle-like electrode that is place in close proximity to the nerve with ultrasound guidance. The aim of this study is to evaluate the effectiveness of PNM in ankle instability.

Subjects were treated once time. The technique consisted in the application of a square wave biphasic electrical current, with 10 Hz frequency, with 250 μs pulse width and the maximal torelable intensity to cause an exacerbated muscle contraction during ten seconds with a rest period of another ten seconds y total number of ten times. The subjects were lying in lateral decubitus. The common peroneal nerve was located with ultrasound (cross section) near to the peroneal head. After, an acupuncture needle (0,30mm x 30mm) was inserted in a long axis approach until the perineurium of the common peroneal nerve (in close proximity)

Subjects were treated once time. The subjects were lying in lateral decubitus. The common peroneal nerve was located with ultrasound (cross section) near to the peroneal head. After, an acupuncture needle (0,30mm x 30mm) was inserted in a long axis approach until the perineurium of the common peroneal nerve (in close proximity). The needle remains in this location during 200 seconds without any electrical current.

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Mdurance EMG system is valid tool to measure muscle activity during isokinetic contractions. It has shown an almost perfect Intraclass Correlation Coefficient>0.81.

Myoton Pro is a device designed to measure and record Oscillation frequency (pitch), dynamic stiffness (stiffness), logarithmic decrement (elasticity), mechanical stress relaxation time and creep. It has shown an excellent reliability, Intraclass Correlation Coefficient 0.91-0.96 in all measures with the exception of elasticity 0.78-0.86

Inclusion Criteria: Ankle instability Exclusion Criteria: Subjects taking NSAIDs, analgesics or muscle relaxants Epilepsy Belonephobia or allergy to metals