High Definition Ultrasound Imaging of the Intermuscular Bridges at the Interscalene Groove

Volunteers will have an ultrasound scanning of both sides of their neck lying in supine position. Sequentially the scanning will start from the base of the neck (supraclavicular fossa) to the upper part of the interscalene groove and then in the reverse direction to the supraclavicular fossa. Images will be recorded as video loops.