Search results
Results from the WOW.Com Content Network
The annular ligament (orbicular ligament) is a strong band of fibers that encircles the head of the radius, and retains it in contact with the radial notch of the ulna. [ 1 ] Per Terminologia Anatomica 1998 , the spelling is "anular", [ 2 ] but the spelling "annular" is frequently encountered.
The head of the radius has a cylindrical form, and on its upper surface is a shallow cup or fovea for articulation with the capitulum of the humerus.The circumference of the head is smooth; it is broad medially where it articulates with the radial notch of the ulna, narrow in the rest of its extent, which is embraced by the annular ligament.
In radial head subluxation, there is little complaint of pain, and the person generally reports pain in the proximal forearm. The mechanism is slippage of the head of the radius under the annular ligament. The distal attachment of the annular ligament covering the radial head is weaker in children than in adults, allowing it to be more easily torn.
It occurs between the circumference of the head of the radius and the ring formed by the radial notch of the ulna and the annular ligament. [2] The interosseous membrane of the forearm and the annular ligament stabilise the joint. [2] A number of nerves run close to the proximal radioulnar joint, including: median nerve; musculocutaneous nerve ...
The zona orbicularis and proximal hip joint capsule are poorly understood. Recent studies seem to confirm that the proximal to middle part of the articular capsule, including the zona orbicularis, acts biomechanically as a locking ring wrapped around the femoral neck and thus is a key structure for hip stability in distraction.
The chief complaint of this disease is usually pain in the dorsal aspect of the upper forearm, and any weakness described is secondary to the pain. Tenderness to palpation occurs over the area of the radial neck. Also, the disease can be diagnosed by a positive "middle finger test", where resisted middle finger extension produces pain.
The underlying mechanism involves slippage of the annular ligament off of the head of the radius followed by the ligament getting stuck between the radius and humerus. [1] Diagnosis is often based on symptoms. [2] X-rays may be done to rule out other problems. [2] Prevention is by avoiding potential causes. [2] Treatment is by reduction. [2]
On the radial side of the retinaculum is the tendon of the flexor carpi radialis, which lies in the groove on the greater multangular between the attachments of the ligament to the bone. The tendons of the palmaris longus and flexor carpi ulnaris are partly attached to the surface of the retinaculum; below, the short muscles of the thumb and ...