Our 16 year old grandson has recently lost bicep muacle mass in right arm. He cannot even throw a beachball.?
Sudden loss? Sudden loss of biceps muscle mass in one arm sounds like a tendon avulsion. The tendon pulls away from the humerus bone. Better take him to his doc. He might need an orthopedic consult. Facioscapularhumeral muscular dystrophy starts more gradually. Also it is inherited as a dominant condition so usually other family members are affected. See doc.
Loss of biceps. Loss of, or abnormal placement of the biceps muscle in the upper arm accompanied by weakness strongly suggest a tear, possibly complete, of the biceps. Depending on whether the tear occurred at the upper or lower end, surgery may be warranted (if done within a couple of weeks). Get it checked out.
Our sixteen year old grandson has experienced a lots of muscle mass in his right arm. Her has a strong bicep, however now can hardly throw a beach ball?
Bicep tendon rupture. If the bulge is on the front and end of arm (near elbow area), then this may be a rupture bicep. See doctor for exam.