If it hurts to straighten your arm, then you may have overextended your arm. Your biceps muscle, known as the biceps brachii, starts from your shoulder on the scapula and attaches on the radius (the thumb-side bone of the two bones in the forearm) by the elbow. It may be that you have damaged this muscle to some extent. This causes pain when bending your elbow and trying to straighten your arm completely.
(This answer provided for NATA by the Southern Utah University Athletic Training Education Program.)
If it hurts to straighten your arm, then you may have overextended
your arm. Your biceps muscle, known as the biceps brachii, starts
from your shoulder on the scapula and attaches on the radius (the
thumb-side bone of the two bones in the...
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National Athletic Trainers’ Association answered:If it hurts to straighten your arm, then you may have overextended your arm. Your biceps muscle, known as the biceps brachii, starts from your shoulder on the scapula and attaches on the radius (the thumb-side bone of the two bones in the forearm) by the elbow. It may be that you have damaged this muscle to some extent. This causes pain when bending your elbow and trying to straighten your arm completely.
