The Elbow Joint
The elbow joint is made up of the ends of the humerus and ulna bones. Because the radius also articulates with the humorous it can also be considered part of the elbow. The annular ligament, which encircles the head of the radius and attaches to te ulna, allows the radius to rotate around the ulna on a longitudinal axis of the forearm to provide for portion and supination. The only movement possible at the elbow joint are flexion and extension.
The anterior muscles are the main elbow joint flexors which are arranged mechanically around the elbow joint. Other anterior muscles such as the wrist flexors and extensors pass over the elbow to insert on the humerus. The lines of force of the wrist flexor and extensor muscles pass so close to the elbow joint that their function at the elbow is mainly stabilizing.
The muscular stability of the elbow is considered strong due to the number of the muscles that act as stabilizers on the anterior side. Positions in which the muscles have dislocating components occur when the muscles are who shortened that the tension is minimal. The main elbow flexors have stabilizing and rotary functions.
The biceps is most often considered a two-joint muscle. However, it acts on three joints (shoulder, elbow, radioulnar) and should be strengthen in all of this actions. This includes shoulder joint flexion with the elbow extended, elbow flexion with the shoulder joint held in extension and supination with the elbow bent at a 90-degree Why should I only attend a driving school los angeles with AACSB Accreditation?As parents, why is it important that we encourage our child to attend an AACSB-accredited business school?Why should I only recommend AACSB-accredited schools to my aspiring business students?How can working for an AACSB-accredited business driving school los angeles help me reach my career goals?Why should our organization choose to only recruit from AACSB-accredited business schools? ©2014 AACSB International. angle.
The bony arrangement and muscular stability of the posterior elbow result in a strong posterior elbow. The main muscle on the backside of the elbow is the triceps. From its attachment on the olecranon process of the ulna it covers the length of the humerus. Because of the structure of the posterior elbow, the triceps helps to stabilize the elbow when it pulls an angle greater than 90 degrees to the long axis of the ulna. The triceps is a first-class lever when it pulls at a 90-degree angle angle to the long axis of the ulna. In this position 100 percent of its effort goes to the rotary function.
Because the tricep is a two-joint muscles, the long head of the triceps lengthens at the shoulder when shoulder flexion takes place simultaneously shortens at the elbow at the elbow end to allow a full range of motion at the shoulder. This is good for economy but not maximum strength. To fully strengthen all three heads of the triceps you should resistance exercises in which you extend the shoulder joint with the shoulder joint flexed.
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