Treat Elbow Injuries – Elbow Sprain, swell And pain Consultant Orthopedic Surgeon
The elbow is the region surrounding the elbow-joint—the ginglymus or hinge joint in the middle of the arm. Three bones form the elbow joint: the humerus of the upper arm, and the paired radius and ulna of the forearm.
The bony prominence at the very tip of the elbow is the olecranon process of the ulna, and the inner aspect of the elbow is called the antecubital fossa.
Two main movements are possible at the elbow:
In the anatomical position (with the forearm supine), the radius and ulna lie parallel to each other. During pronation, the ulna remains fixed, and the radius rolls around it at both the wrist and the elbow joints. In the prone position, the radius and ulna appear crossed.
Most of the force through the elbow joint is transferred between the humerus and the ulna. Very little force is transmitted between the humerus and the radius. (By contrast, at the wrist joint, most of the force is transferred between the radius and the carpus, with the ulna taking very little part in the wrist joint).
The muscles in relation with the joint are:
The arteries supplying the joint adontre derived from the anastomosis between the profunda and the superior and inferior ulnar collateral branches of the brachial, with the anterior, posterior, and interosseous recurrent branches of the ulnar, and the recurrent branch of the radial. These vessels form a complete anastomotic network around the joint.
The nerves of the joint are a twig from the ulnar, as it passes between the medial condyle and the olecranon; a filament from the musculocutaneous, and two from the median.
The elbow-joint comprises three different portions. All these articular surfaces are enveloped by a common synovial membrane, and the movements of the whole joint should be studied together.
The combination of the movements of flexion and extension of the forearm with those of pronation and supination of the hand, which is ensured by the two being performed at the same joint, is essential to the accuracy of the various minute movements of the hand.
The hand is only directly articulated to the distal surface of the radius, and the ulnar notch on the lower end of the radius travels around the lower end of the ulna. The ulna is excluded from the wrist-joint by the articular disk.
Thus, rotation of the head of the radius around an axis passing through the center of the radial head of the humerus imparts circular movement to the hand through a very considerable arc.
The trochlea of the humerus is received into the semilunar notch of the ulna, and the capitulum of the humerus articulates with the fovea on the head of the radius. The articular surfaces are connected together by a capsule, which is thickened medially and laterally, and, to a less extent, in front and behind. These thickened portions are usually described as distinct ligaments.
The major ligaments are the ulnar collateral ligament, radial collateral ligament, and annular ligament.
The synovial membrane is very extensive. It extends from the margin of the articular surface of the humerus, and lines the coronoid, radial and olecranon fossæ on that bone; it is reflected over the deep surface of the capsule and forms a pouch between the radial notch, the deep surface of the annular ligament, and the circumference of the head of the radius. Projecting between the radius and ulna into the cavity is a crescentic fold of synovial membrane, suggesting the division of the joint into two; one the humeroradial, the other the humeroulnar.
Between the capsule and the synovial membrane are three masses of fat:
The now obsolete length unit ell relates closely to the elbow. This becomes especially visible when considering the Germanic origins of both words, Elle (ell, defined as the length of a male forearm from elbow to fingertips) and Ellbogen (elbow).
It is unknown when or why the second “l” was dropped from English usage of the word, but the elbow is shaped in an “L-shaped” unit, and thus the term elbow came to fruition.
When the arm is extended, with the palm facing forward or up, the bones of the humerus and forearm are not perfectly aligned. The deviation from a straight line occurs in the direction of the thumb, and is referred to as the “carrying angle” (visible in the right half of the picture, right).
The carrying angle permits the arm to be swung without contacting the hips. Women on average have smaller shoulders and wider hips than men, which may necessitate a greater carrying angle. There is, however, extensive overlap in the carrying angle between individual men and women, and a sex-bias has not been consistently observed in scientific studies .
The angle is greater in the dominant limb than the non-dominant limb of both sexes , suggesting that natural forces acting on the elbow modify the carrying angle. Developmental , ageing and possibly racial influences add further to the variability of this parameter.
The carrying angle can influence how objects are held by individuals – those with a more extreme carrying angle may be more likely to pronate the forearm when holding objects in the hand to keep the elbow closer to the body.
The types of disease most commonly seen at the elbow are due to injury.
Two of the most common injuries at the elbow are overuse injuries: tennis elbow and golfer’s elbow. Golfer’s elbow involves the tendon of the common flexor origin which originates at the medial epicondyle of the humerus (the “inside” of the elbow). Tennis elbow is the equivalent injury, but at the common extensor origin (the lateral epicondyle of the humerus).
There are three bones at the elbow joint, and any combination of these bones may be involved in a fracture of the elbow. Patients who are able to fully extend their arm at the elbow are unlikely to have a fracture (98% certainty) and an X-ray is not required as long as an olecranon fracture is ruled out.
Infection of the elbow joint (septic arthritis) is uncommon. It may occur spontaneously, but may also occur in relation to surgery or infection elsewhere in the body (for example, endocarditis).
Elbow arthritis is usually seen in individuals with rheumatoid arthritis or after fractures that involve the joint itself. When the damage to the joint is severe, fascial arthroplasty or elbow joint replacement may be considered.
This article was originally based on an entry from a public domain edition of Gray’s Anatomy. As such, some of the information contained within it may be outdated.
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