The brachial plexus (the bundle of nerves that supplies the arm, forearm, and hand) travels between the anterior and middle scalenes before diving under the clavicle and heading to the axilla (armpit) and into the arm. These nerves can be compressed at several places along their course including the areas where they pass through the scalenes and where they pass under the pectoralis minor. An elevated 1st rib or accessory (extra) rib can also cause compression of these nerves. The condition is known as thoracic outlet syndrome and it should be relatively easy for you to find more information about this online. Please note that there are a great number of other conditions that can cause a loss of grip strength and not all of them are muscular or myofascial. If your symptoms are worsening despite your efforts, it may be time to find a qualified physician or physical therapist (preferably one with some knowledge of strength and conditioning and who understands your training goals)

Brian Bochette, PT, CSCS