The elbow joint is composed of the articulations of the distal humerus and proximal radius and ulna. The humeroulnar joint is a solid hinge joint with a deep articulation and strong ligaments directing elbow flexion and extension. The articulation between the humerus and radius allows both hinging and rotation. The rounded proximal end of the radius rotates within a corresponding notch on the ulna. While all three joints function independently, they are contained within a single joint capsule, and movement occurs at all joints simultaneously.

Several large muscles of the upper arm, including the biceps brachii and brachialis, cross the elbow anteriorly. The brachioradialis and wrist extensor muscles are found on the lateral forearm, while the wrist and hand flexors cover the entire anterior surface. Another important muscle in the anterior elbow is the pronator teres, which lies deep to the bicipital aponeurosis and spans the area from the medial epicondyle of the humerus to the middle third of the lateral radius.

Function

The elbow is a stable joint capable of generating tremendous amounts of force in the upper extremity. The high degree of motion at the shoulder, rotational motions of the forearm (pronation and supination), and the finer motions available at the wrist and hand direct those forces and optimally position the limb. Proper function relies on optimal alignment and coordinated force production between all of the structures.

Ideally, the shoulder maintains harmony between stability and mobility, perfectly positioning the upper extremity for myriad tasks. The elbow provides a stable platform for powerful motions needed to grasp, lift, push, and pull. Forces generated in, or transferred through, the elbow are guided and fine-tuned by the network of tendons and smaller muscles of the hand.

Dysfunction

Unfortunately, the human body is subject to several specific forces that may disrupt the perfect symphony of movement in the upper extremity. Our upright posture is constantly subject to gravity and tends toward a flexed position over time. Additionally, our eyes are on the front of our head, and we tend to perform tasks with our hands in front so we can see what we are doing. Both of these conditions perpetuate postural deviations such as forward head and rounded shoulders. The entire upper extremity tends to spiral internally toward the anterior midline in an effort to bring objects into our field of vision.

Repetitive or prolonged positioning may lead to specific patterns of muscle tension and corresponding inhibition, as well as corresponding fascial changes. Shortening and hypertension occur in structures of the anterior shoulder, medial arm and elbow, and into the anterior forearm and hand. This spiraling pattern is easily observed—when clients are standing—as difficulty or inability to maintain a relaxed arm position with the thumbs facing forward. When lying supine, the forearm remains pronated and the wrist and elbow flexed. Oddly, clients often complain of tension or discomfort in the elongated structures of the posterior neck and shoulder and the posterior and lateral elbow, forearm, and wrist.

Intervention

It is important to acknowledge that the previously identified postural deviation occurs at multiple regions. Addressing proper positioning of the upper extremity relative to the axial skeleton is merely one step in the process. Reducing excessive scapular protraction, medial rotation of the glenohumeral joint, excessive pronation at the forearm, and hyperflexion of the wrist and hand is equally important. Hypertonicity and fascial restriction of the pronator teres, brachioradialis, and wrist and hand flexors are often overlooked and should be addressed.