The biceps brachii is a large muscle of the upper arm. Originally called “musculus”, it got its name from the Latin for mouse, referring to the arch of a mouse’s back. It then gave its name back to all other muscles. The biceps is considered generally representative of strength across a variety of cultures.

The biceps are a common source of pain in the front of the shoulder and occasionally the inside of the elbow. It is composed of two “heads” with slightly different attachments. The long head originates on the upper margin of the shoulder socket. The short head originates in the coracoid process on the front of the shoulder. Both heads proceed down the humerus, past the elbow, into the forearm and attach to the radius.

The actions of the biceps are complex. The primary function is to flex and rotate your forearm, moving it from pronation (palm down) to supination (palm up). It also flexes your arm at both the elbow and the shoulder and assists the rotator cuff in stabilizing your shoulder joint.

Trigger points in your biceps cause superficial pain in the front of your shoulder, sometimes extending down the front of your arm.  This localized pain can be preliminary to biceps tendonitis and impingement syndrome. Pain may be present in the upper arm and inside of the elbow. You may have trouble keeping your arm extended when reaching behind your back.

Biceps brachii trigger points are typically activated from sudden or repetitive overload in activities with your arms outstretched, episodic elbow flexion load such as using an electric hedge trimmer, vigorous supination similar to a manual screwdriver, repetitive activities such as typing or playing the violin, and sudden stretching such as preventing a fall by reaching behind for a railing.

Corrective actions include trigger point pressure release, stretching, and avoiding activities that overload the muscle.