| Deltoid tuberosity | |
|---|---|
 Left humerus. Anterior view. (Deltoideus labeled at center right.) | |
| Details | |
| Identifiers | |
| Latin | tuberositas deltoidea humeri |
| TA98 | A02.4.04.020 |
| TA2 | 1193 |
| FMA | 23418 |
| Anatomical terms of bone | |
In human anatomy, the deltoid tuberosity is a rough, triangular [1] area on the antero lateral (front-side) surface of the middle of the humerus. [2] It is a site of attachment of deltoid muscle. [2]
The deltoid tuberosity has been reported as very prominent in less than 10% of people. [3]
The deltoid tuberosity develops through endochondral ossification in a two-phase process. [4] The initiating signal is tendon-dependent, whilst the growth phase is muscle-dependent. [4]
The deltoid tuberosity is at risk of avulsion fracture. [5] These fractures may be managed conservatively with rest. [5]
In mammals, the humerus displays a wide morphological variation. The size and orientation of its functionally important features, including the deltoid tubercle, greater tubercle, and medial epicondyle, are pivotal to an animal's style of locomotion and habitat. In cursorial (running) animals such as the pronghorn, the deltoid tubercle is located about a quarter of the way down the shaft, which allows for rapid but relatively weak limb flexion and extension. In natatorial (swimming) animals such as the North American river otter, the tubercle is located nearly halfway down the shaft, which allows for powerful limb flexion and extension. The tuberosity can be very pronounced in fossorial (digging) animals, such as the mountain beaver. [6] It is very superficial in horses. [7]
The humerus is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a rounded head, a narrow neck, and two short processes. The body is cylindrical in its upper portion, and more prismatic below. The lower extremity consists of 2 epicondyles, 2 processes, and 3 fossae. As well as its true anatomical neck, the constriction below the greater and lesser tubercles of the humerus is referred to as its surgical neck due to its tendency to fracture, thus often becoming the focus of surgeons.
The biceps or biceps brachii are a large muscle that lies on the front of the upper arm between the shoulder and the elbow. Both heads of the muscle arise on the scapula and join to form a single muscle belly which is attached to the upper forearm. While the biceps crosses both the shoulder and elbow joints, its main function is at the elbow where it flexes the forearm and supinates the forearm. Both these movements are used when opening a bottle with a corkscrew: first biceps screws in the cork (supination), then it pulls the cork out (flexion).
In human anatomy, the ulnar nerve is a nerve that runs near the ulna bone. The ulnar collateral ligament of elbow joint is in relation with the ulnar nerve. The nerve is the largest in the human body unprotected by muscle or bone, so injury is common. This nerve is directly connected to the little finger, and the adjacent half of the ring finger, innervating the palmar aspect of these fingers, including both front and back of the tips, perhaps as far back as the fingernail beds.
The tibia, also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates ; it connects the knee with the ankle. The tibia is found on the medial side of the leg next to the fibula and closer to the median plane. The tibia is connected to the fibula by the interosseous membrane of leg, forming a type of fibrous joint called a syndesmosis with very little movement. The tibia is named for the flute tibia. It is the second largest bone in the human body, after the femur. The leg bones are the strongest long bones as they support the rest of the body.
The human shoulder is made up of three bones: the clavicle (collarbone), the scapula, and the humerus as well as associated muscles, ligaments and tendons.
In humans and many other primates, the calcaneus or heel bone is a bone of the tarsus of the foot which constitutes the heel. In some other animals, it is the point of the hock.
The radius or radial bone is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna. The ulna is longer than the radius, but the radius is thicker. The radius is a long bone, prism-shaped and slightly curved longitudinally.
The internal obturator muscle or obturator internus muscle originates on the medial surface of the obturator membrane, the ischium near the membrane, and the rim of the pubis.
The shoulder joint is structurally classified as a synovial ball-and-socket joint and functionally as a diarthrosis and multiaxial joint. It involves an articulation between the glenoid fossa of the scapula and the head of the humerus. Due to the very loose joint capsule that gives a limited interface of the humerus and scapula, it is the most mobile joint of the human body.
In human anatomy, the fibularis brevis is a muscle that lies underneath the fibularis longus within the lateral compartment of the leg. It acts to tilt the sole of the foot away from the midline of the body (eversion) and to extend the foot downward away from the body at the ankle.
The gluteal tuberosity is the lateral one of the three upward prolongations of the linea aspera of the femur, extending to the base of the greater trochanter. It serves as the principal insertion site for the gluteus maximus muscle.
The nuchal ligament is a ligament at the back of the neck that is continuous with the supraspinous ligament.
The greater tubercle of the humerus is the outward part the upper end of that bone, adjacent to the large rounded prominence of the humerus head. It provides attachment points for the supraspinatus, infraspinatus, and teres minor muscles, three of the four muscles of the rotator cuff, a muscle group that stabilizes the shoulder joint. In doing so the tubercle acts as a location for the transfer of forces from the rotator cuff muscles to the humerus.
Beneath the neck of the radius, on the medial side, is an eminence, the radial tuberosity; its surface is divided into:
The coracoacromial ligament is a strong triangular ligament between the coracoid process and the acromion. It protects the head of the humerus. Its acromial attachment may be repositioned to the clavicle during reconstructive surgery of the acromioclavicular joint.
The supraglenoid tubercle is a region of the scapula from which the long head of the biceps brachii muscle originates. It is a small, rough projection superior to the glenoid cavity near the base of the coracoid process. The term supraglenoid is from the Latin supra, meaning above, and glenoid, meaning socket or cavity.
The common extensor tendon is a tendon that attaches to the lateral epicondyle of the humerus.
The tuberosity of the ulna is a rough eminence on the proximal end of the ulna. It occurs at the junction of the antero-inferior surface of the coronoid process with the front of the body. It provides an insertion point to a tendon of the brachialis.
The surgical neck of the humerus is a bony constriction at the proximal end of shaft of humerus. It is situated distal to the greater tubercle and lesser tubercle, and proximal to the deltoid tuberosity.
The stay apparatus is an arrangement of muscles, tendons and ligaments that work together so that an animal can remain standing with virtually no muscular effort. It is best known as the mechanism by which horses can enter a light sleep while still standing up. The effect is that an animal can distribute its weight on three limbs while resting a fourth in a flexed, non-weight bearing position. The animal can periodically shift its weight to rest a different leg and thus all limbs are able to be individually rested, reducing overall wear and tear. The relatively slim legs of certain large mammals such as horses and cows would be subject to dangerous levels of fatigue if not for the stay apparatus.
...in seven out of 100 scans reviewed.
