"Shoulder The human shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone) as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder make up the shoulder joints. The shoulder joint, also known as the glenohumeral joint, is the major joint of the shoulder, but can more broadly include the acromioclavicular joint. In human anatomy, the shoulder joint comprises the part of the body where the humerus attaches to the scapula, and the head sits in the glenoid cavity. The shoulder is the group"
"is a narrow area distal to the tubercles that is a common site of fracture. It makes contact with the axillary nerve and the posterior humeral circumflex artery. Upper extremity of humerus The upper or proximal extremity of the humerus consists of the bone's large rounded head joined to the body by a constricted portion called the neck, and two eminences, the greater and lesser tubercles. The head (""caput humeri""), is nearly hemispherical in form. It is directed upward, medialward, and a little backward, and articulates with the glenoid cavity of the scapula to form the glenohumeral joint (shoulder joint)."
"humerus is one of the three long bones of the arm. It joins with the scapula at the shoulder joint and with the other long bones of the arm, the ulna and radius at the elbow joint. The elbow is the hinge joint between the end of the humerus and the ends of the radius and ulna. The humerus cannot be broken easily. Its strength allows it to handle loading up to . The arm is divided by a fascial layer (known as lateral and medial intermuscular septa) separating the muscles into two ""osteofascial compartments"": the anterior and the posterior"
"""collarbone"" and the ""scapula"" or the ""shoulder blade"". The spelling ""humerus"" is actually incorrect in classical Latin. Those three bones were referred to as the ""ossa"" (Latin: bones) ""umeri"" (Latin: of the umerus). Umerus was also used to refer specifically to the shoulder. This mirrors the use of ὦμος in ancient Greek as that could refer to the ""shoulder with the upper arm"" or to the ""shoulder"" alone. Since Celsus, the ""os umeri"" could refer specifically to the ""upper bone of the arm"". The 16th century anatomist Andreas Vesalius used ""humerus"" to refer to the clavicle. Besides the aforementioned ""os"
"humerus differs from the femur in many regards, one of which being that there is a more extensive network of bony trabeculae in the humerus near the meduallary cavity of the bone. The globular osteocyte lacunae become more flattened as you get closer and closer to the midshaft of the humerus. While the vasculature is present, the humerus contains no secondary osteons. The radii and ulnae of ""Thrinaxodon"" represent roughly the same histological patterns. In contrast to the humerii and femora, the parallel-fibred region is far more distinct in the distal bones of the forelimb. The medullary cavities are surrounded"
"the humerus (upper bone of the forelimb) is called the glenoid. The glenoid is important because it defines the range of motion of the humerus. Glenoid cavity The glenoid cavity or glenoid fossa of scapula is a part of the shoulder. It is a shallow, pyriform articular surface, which is located on the lateral angle of the scapula. It is directed laterally and forward and articulates with the head of the humerus; it is broader below than above and its vertical diameter is the longest. This cavity forms the glenohumeral joint along with the humerus. This type of joint is"
"Upper extremity of humerus The upper or proximal extremity of the humerus consists of the bone's large rounded head joined to the body by a constricted portion called the neck, and two eminences, the greater and lesser tubercles. The head (""caput humeri""), is nearly hemispherical in form. It is directed upward, medialward, and a little backward, and articulates with the glenoid cavity of the scapula to form the glenohumeral joint (shoulder joint). The circumference of its articular surface is slightly constricted and is termed the anatomical neck, in contradistinction to a constriction below the tubercles called the surgical neck which"
"humerus found at Mont Ventoux, near Bédoin, by Prosper Renaux (1793–1852) in 1841. The bone was 90 cm (35.43 in) long, 33 cm (13 in) wide at the proximal end, 15 cm (5.91 in) wide in the middle, and 25 cm (9.84 cm) wide at the distal end. From the same locality, he referred a conical tooth he thought could belong to a larger second species, and from elsewhere added to ""A."" sp. (a practice used to denote that the remains belong to a certain genus, but the species is not known) a partial humerus and ulna. The proximal part"
"Humeroulnar joint The humeroulnar joint (ulnohumeral or trochlear joint), is part of the elbow-joint. It is composed of two bones, the humerus and ulna, and is the junction between the trochlear notch of ulna and the trochlea of humerus. It is classified as a simple hinge-joint, which allows for movements of flexion, extension and circumduction. Owing to the obliquity of the trochlea of the humerus, this movement does not take place in the antero-posterior plane of the body of the humerus. When the forearm is extended and supinated, the axis of the arm and forearm are not in the same"
"in humans. A similar change occurred in the fibula bone of the hind limbs. These changes were first seen in the genus ""Merychippus"", approximately 17 million years ago. The anatomy of the forelegs begin at the scapula. This is the shoulder in which provides the ease of movement as it is connected to various bones surrounding it such as the cervical vertebra (a section of the spine). The next bone is the humerus which leads onto the radius below. The radius is then connected to the bones of the knee. The carpus is located at front of the knee and"
"Scapula In anatomy, the scapula (plural scapulae or scapulas), also known as shoulder bone, shoulder blade, wing bone or blade bone, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones the scapulae are paired, with the scapula on either side of the body being roughly a mirror image of the other. The name derives from early Roman times when it was thought that the bone resembled a trowel or small shovel. In compound terms, the prefix omo- is used for the shoulder blade in Latin medical terminology. The prefix is"
"which is the bottom of the humerus near the elbow. Proximal fractures are classified into one of four types of fractures based on the displacement of the greater tubercle, the lesser tubercle, the surgical neck, and the anatomical neck, which are the four parts of the proximal humerus, with fracture displacement being defined as at least one centimeter of separation or an angulation greater than 45 degrees. One-part fractures involve no displacement of any parts of the humerus, two-part fractures have one part displaced relative to the other three; three-part fractures have two displaced fragments, and four-part fractures have all"
"Ossification of humerus The humerus is ossified from ""eight"" centers, one for each of the following parts: the body, the head, the greater tubercle, the lesser tubercle, the capitulum, the trochlea, and one for each epicondyle. One primary and seven secondary centres . The center for the body appears near the middle of the diaphysis in the eighth week of fetal life, and soon extends toward the extremities. This is the primary centre At birth the humerus is ossified in nearly its whole length, only the extremities remaining cartilaginous. During the first year, sometimes before birth, ossification commences in the"
"Body of humerus The body or shaft of the humerus is almost cylindrical in the upper half of its extent, prismatic and flattened below, and has three borders and three surfaces. The anterior border runs from the front of the greater tubercle above to the coronoid fossa below, separating the antero-medial from the antero-lateral surface. Its upper part is a prominent ridge, the crest of the greater tubercle; it serves for the insertion of the tendon of the pectoralis major muscle. About its center it forms the anterior boundary of the deltoid tuberosity, on which the deltoid muscle attaches; below,"
"Glenohumeral ligaments In human anatomy, the glenohumeral ligaments (GHL) are three ligaments on the anterior side of the glenohumeral joint (i.e. between the glenoid cavity of the scapula and the head of the humerus; colloquially called the shoulder joint). Reinforcing the anterior glenohumeral joint capsule, the superior, middle, and inferior glenohumeral ligaments play different roles in the stability of the head of the humerus depending on arm position and degree of rotation. The ligaments may be best seen by opening the capsule at the back of the joint and removing the head of the humerus: In addition to these, the"
"the ulna. The axillary nerve is located at the proximal end, against the shoulder girdle. Dislocation of the humerus's glenohumeral joint has the potential to injure the axillary nerve or the axillary artery. Signs and symptoms of this dislocation include a loss of the normal shoulder contour and a palpable depression under the acromion. The radial nerve follows the humerus closely. At the midshaft of the humerus, the radial nerve travels from the posterior to the anterior aspect of the bone in the ""spiral groove"". A fracture of the humerus in this region can result in radial nerve injury. The"
"epicondyle of the humerus. Extension in the humeroulnar joint is produced by the triceps brachii and anconeus muscle, with a tiny contribution from the muscles arising from the lateral epicondyle of the humerus, such as the extensor digitorum muscle. Humeroulnar joint The humeroulnar joint (ulnohumeral or trochlear joint), is part of the elbow-joint. It is composed of two bones, the humerus and ulna, and is the junction between the trochlear notch of ulna and the trochlea of humerus. It is classified as a simple hinge-joint, which allows for movements of flexion, extension and circumduction. Owing to the obliquity of the"
"by striking the medial epicondyle of the humerus from posteriorly, or inferiorly with the elbow flexed. The ulnar nerve is trapped between the bone and the overlying skin at this point. This is commonly referred to as bumping one's ""funny bone"". This name is thought to be a pun, based on the sound resemblance between the name of the bone of the upper arm, the ""humerus"" and the word ""humorous"". Alternatively, according to the Oxford English Dictionary it may refer to ""the peculiar sensation experienced when it is struck"". The ulnar nerve originates from the C8-T1 nerve roots (and occasionally"
"Femur The femur (, pl. ""femurs"" or ""femora"" ) or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with the tibia and kneecap forming the knee joint. By most measures the femur is the strongest bone in the body. The femur is also the longest bone in the human body. The femur is the only bone in the upper leg. The two femurs converge medially toward the knees, where they articulate"
"Articular capsule of the humerus The articular capsule of the humerus is the articular capsule of the shoulder joint. It completely encircles the joint, being attached, above, to the circumference of the glenoid cavity beyond the glenoidal labrum; below, to the anatomical neck of the humerus, approaching nearer to the articular cartilage above than in the rest of its extent. It is thicker above (superior) and below (inferior) than elsewhere, and is so remarkably loose and lax, that it has no action in keeping the bones in contact, but allows them to be separated from each other more than 2.5"
"is oriented obliquely sideways and to below. The coracoid is in all known specimens fused with the scapula into a scapulocoracoid, lacking a visible suture. The coracoid as such is an oval bone plate, with its longest side attached to the scapula. It is pierced by a large oval foramen but the usual boss for the attachment of the upper arm muscles is lacking. The humerus is very robust with strongly expanded upper and lower ends. Humerus specimen OUMNH J.13575 has a length of 388 millimetres. Its shaft circumference equals about half of the total humerus length. The humerus head"
"the scapula (shoulder blade) and the coracoid, both of which directly articulated with the clavicle. The clavicle was present in saurischian dinosaurs but largely absent in ornithischian dinosaurs. The place on the scapula where it articulated with the humerus (upper bone of the forelimb) is the called the glenoid. The scapula serves as the attachment site for a dinosaur's back and forelimb muscles. Scapula In anatomy, the scapula (plural scapulae or scapulas), also known as shoulder bone, shoulder blade, wing bone or blade bone, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like"
"the cervical spine of the neck) also may generate pain that the brain may interpret as arising from the shoulder. The shoulder joint is composed of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone) (see diagram). Two joints facilitate shoulder movement. The acromioclavicular (AC) joint is located between the acromion (part of the scapula that forms the highest point of the shoulder) and the clavicle. The glenohumeral joint, to which the term ""shoulder joint"" commonly refers, is a ball-and-socket joint that allows the arm to rotate in a circular fashion or to hinge"
"Trochlea of humerus In the human arm, the humeral trochlea is the medial portion of the articular surface of the elbow joint which articulates with the trochlear notch on the ulna in the forearm. In humans and apes it is trochleariform (or trochleiform), as opposed to cylindrical in most monkeys and conical in some prosimians. It presents a deep depression between two well-marked borders; it is convex from before backward, concave from side to side, and occupies the anterior, lower, and posterior parts of the extremity. The trochlea has the capitulum located on its lateral side and the medial epicondyle"
"the latter below the radial sulcus. Body of humerus The body or shaft of the humerus is almost cylindrical in the upper half of its extent, prismatic and flattened below, and has three borders and three surfaces. The anterior border runs from the front of the greater tubercle above to the coronoid fossa below, separating the antero-medial from the antero-lateral surface. Its upper part is a prominent ridge, the crest of the greater tubercle; it serves for the insertion of the tendon of the pectoralis major muscle. About its center it forms the anterior boundary of the deltoid tuberosity, on"
"Malleus The malleus or hammer is a hammer-shaped small bone or ossicle of the middle ear which connects with the incus and is attached to the inner surface of the eardrum. The word is Latin for ""hammer"" or ""mallet"". It transmits the sound vibrations from the eardrum to the ""incus"". The malleus is a bone situated in the middle ear. It is the first of the three ossicles, and attached to the tympanic membrane. The ""head of the malleus"" is the large protruding section, which attaches to the incus. The head connects to the ""neck of malleus"", and the bone"
"Greater tubercle The greater tubercle of the humerus is situated lateral to the head of the humerus and posterolateral to the lesser tubercle. Its upper surface is rounded and marked by three flat impressions. The lateral surface of the greater tubercle is convex, rough, and continuous with the lateral surface of the body. Between the greater tubercle and the lesser tubercle is the bicipital groove (intertubercular sulcus). All three of the muscles that attach to the greater tubercle are part of the rotator cuff, a muscle group that stabilizes the shoulder joint. The fourth muscle of the rotator cuff (the"
"the midpoint of the humeral shaft, the bone is mildly constricted, being approximately 20% narrower than the maximum width. The bottom end of the humerus is larger than the top end; it bears three articular facets, with one for the preaxial accessory element (the smallest of the three), one for the radius (the tallest of the three), and one for the ulna (which forms an angle of 120° with the radial facet). ""Sveltonectes"", ""Nannopterygius"", ""Platypterygius hauthali"", and ""Platypterygius platydactylus"" all only have two; ""Maiaspondylus"", ""Aegirosaurus"", ""Brachypterygius"", and ""Platypterygius americanus"" also have three, but the second facet articulates with a different"
"of the humerus. It as an extremely mobile joint that is stabilized by surrounding soft tissues such as the joint capsule, muscles, and ligaments. The greater and lesser tuberosities are bony landmarks of the proximal humerus and serve as attachment sites for musculature. The anterior and posterior humeral circumflex arteries branch off of the axillary artery to provide the majority of the blood supply to the proximal humerus. The axillary nerve courses inferior to the shoulder joint and innervates the deltoid and teres minor muscles. It also provides sensation at the skin overlying the shoulder. This nerve is the most"
"Humerus fractures usually occur after physical trauma, falls, excess physical stress, or pathological conditions such as tumors. Falls are the most common cause of proximal and shaft fractures, and those who experience a fracture from a fall usually have an underlying risk factor for bone fracture. Distal fractures occur most frequently in children who attempt to break a fall with an outstretched hand. Fractures of the humerus may be classified by the location into proximal region, which is near the shoulder, the middle region or shaft, and the distal region, which is near the elbow. These locations can further be"
"the head of the humerus in the glenoid cavity during movement. The cuff adheres to the glenohumeral capsule and attaches to the head of the humerus. Together, these keep the humeral head in the glenoid cavity, preventing upward migration of the humeral head caused by the pull of the deltoid muscle at the beginning of arm elevation. The infraspinatus and the teres minor, along with the anterior fibers of the deltoid muscle, are responsible for external rotation of the arm. The four tendons of these muscles converge to form the rotator cuff tendon. This tendon, along with the articular capsule,"
"is an indentation distal to the head of the humerus on which the articular capsule attaches. The greater tubercle (""tuberculum majus""; greater tuberosity) is situated lateral to the head and lesser tubercle, and just lateral to the anatomical neck. Its upper surface is rounded and marked by three flat impressions: the highest of these gives insertion to the supraspinatus muscle; the middle to the infraspinatus muscle; the lowest one, and the body of the bone for about 2.5 cm. below it, to the teres minor muscle. The lateral surface of the greater tubercle is convex, rough, and continuous with the"
"humerus. However the socket of the glenoid cavity of the scapula is itself quite shallow and is made deeper by the addition of the glenoid labrum. The glenoid labrum is a ring of cartilaginous fibre attached to the circumference of the cavity. This ring is continuous with the tendon of the biceps brachii above. Significant joint spaces are: The axillary space is an anatomic space between the associated muscles of the shoulder. This space transmits the subscapular artery and axillary nerve. The shoulder joint has a very loose joint capsule known as the articular capsule of the humerus and this"