Ulnar fractures cause severe pain, difficulty in moving the joint affected, and even deformity of the arm if the fracture is compound. The supraspinatus muscle is a rotator cuff muscle located in the shoulder, specifically in the supraspinatus fossa, a concave depression in the rear…. The quadratus plantae is a muscle in the foot that extends from the anterior front of the calcaneus heel bone to the tendons of the digitorum…. The depressor labii inferioris muscle is a four-sided facial muscle located in the jaw area that draws the lower lip down and to the side.
The muscles of the face give it general form and contour, help you outwardly express your feelings, and enable you to chew your food. The quadriceps femoris is a group of muscles located in the front of the thigh.
The Latin translation of 'quadriceps' is 'four headed,' as the group…. The palmaris brevis muscle lies just underneath the skin. It is a short muscle on the flat of the hand. The muscle begins at the flexor retinaculum in…. The movement of the upper arm and shoulder is controlled by a group of four muscles that make up the rotator cuff.
The small rounded part on the distal ulnar surface is the head, and it articulates with the cup-shaped ulnar notch of the radius and the triangular fibrocartilage articular disc, a cartilage structure that keeps the ulna from forming any direct articulations with the carpal bones [7, 11]. The alignment of the ulnar head and the ulnar notch allows the distal end of the ulna work as a pivot so the radius can rotate around it in all directions [8].
The styloid process is a small bony protrusion extending from the posterior medial side of the head [7]. This is where the ulnar collateral ligament UCL of the wrist attaches [8]. The borders and surfaces of the ulnar shaft are the primary site for muscular attachments to this bone [3] :. Primary blood supply is provided by the ulnar artery, as well as its branch the common interosseous artery, which then further branches into the volar and posterior interosseous arteries, still supplying the ulna [6].
The anterior interosseous nerve, branching from the median nerve, innervates the ulna on the volar side, while posteriorly it is innervated by the dorsal interosseous nerve, a branch of the radial nerve [6]. Proper movement of the ulna, along with all the attached muscles is instrumental for doing anything with our hand, from extending or flexing the arm, picking something up, throwing or holding something to eating, driving, and typing [8].
Ulnar fractures are quite common, with the points where it joins with the radius and the fibrocartilage articular disc at the wrist being most frequently injured. Dislocations are also common, especially on the elbow side [14, 15]. Another condition associated with it is the Ulnar impaction syndrome Ulnar abutment where the ulna may be longer than the radius on the distal end, causing it to bump into the wrist bones, leading to pain [16].
The ulna is longer but much narrower than the radius [3]. This is referred to as the ulna length-to-height formula. Leave a Reply Cancel reply Your email address will not be published.
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