Medical Gross Anatomy: Chapter 7 - Upper Limb
Terms in this set (82)
the area of upper limb attachment to the trunk.
between the shoulder and the elbow joint.
the bone of the arm
between the elbow joint and the wrist joint.
distal to the wrist joint
position the hand in space for use as a mechanical and sensory tool
the major function of the upper limb
glenohumeral joint (shoulder joint)
allows the arm to move around 3 axes with a wide range of motion. movements of arm at this joint are flexion, extension, abduction, adduction, medial rotation (internal rotation), and circumduction
major movements here are flexion and extension of the forearm.
because the hand is articulated with the radius, it can be efficiently moved from a palm-anterior position to a palm-posterior position simply by crossing the distal end of the radius over the ulna.t his movement occurs solely in the forearm.
returning the hand to the anatomical position after pronation
at this joint, the hand can be abducted, adducted, flexed, extended, and circumducted.
proximal end of the humerus
the bone framework of the shoulder consist of:
pectoral girdle (shoulder girdle)
the clavicle and scapula
the only bony attachment between the trunk and the upper limb. it has a gentle S-shaped contour, with the forward-facing convex part medial and the forward-facing concave part lateral.
the inferior surface of the lateral third of the clavicle possesses a distinct tuberosity consisting of this tubercle and lateral roughening.
the inferior surface of the lateral third of the clavicle possesses a distinct tuberosity consisting of a tubercle and this lateral roughening for attachment of the important coracoclavicular ligament.
a large, flat triangular bone with 3 angles, 3 borders, 2 surfaces, and 3 processes
lateral angle of scapula
marked by a shallow, somewhat comma-shaped glenoid cavity
articulates with the head of the humerus to form the glenohumeral joint
a large triangular-shaped roughening inferior to the glenoid cavity; is the site of attachment for the long head of the triceps brachii mm
located superior to the glenoid cavity and is the site of attachment for the long head of the biceps brachii
a prominent spine subdivides the posterior surface of the scapula into this small, superior fossa
a prominent spine subdivides the posterior surface of the scapula into this much larger, inferior fossa.
an anterolateral projection of the spine; arches over the glenohumeral joint and articulates, via a small oval facet on its distal end, with the clavicle
greater scapular notch (spingoglenoid notch)
the region between the lateral angle of the scapula and the attachment of the spine to the posterior surface of the scapula
costal surface of the scapula
unremarkable, being characterized by a shallow concave subscapular fossa over much of its extent. this plus its margins provide for muscle attachment, and the costal surface, together with its related muscle (subscapularis) moves freely over the underlying thoracic wall.
concave, anterior surface of scapula
lateral border of the scapula
strong and thick for muscle attachment
the superior border of the scapula is marked on its lateral end by:
a hooklike structure that projects anterolaterally and is positioned directly inferior to the lateral part of the clavicle.
small but distinct; an indentation that lies immediately medial to the root of the coracoid process
head of the humerus
half-spherical in shape and projects medially and somewhat superiorly to articulate with the much smaller glenoid cavity of the scapula.
very short and is formed by a narrow constriction immediately distal to the head. it lies between the head and the greater and lesser tubercles laterally, and between the head and the shaft more medially.
greater tubercle of the humerus
lateral in position. its superior surface and posterior surface are marked by 3 smooth facets for muscle tendon attachment:
1) superior facet for attachment of supraspinatus.
2) middle facet is for attachment of infraspinatus.
3) inferior facet is for attachment of teres minor.
lesser tubercle of the humerus
anterior in position and its surface is marked by a large, smooth impression for attachment of the subscapularis muscle.
intertubercular sulcus (bicipital groove)
separates the greater and lesser tubercles and continues inferiorly onto the proximal shaft of the humerus. the tendon of the long head of the biceps brachii passes through this sulcus. roughenings on the lateral and medial lips and on the floor of this structure mark sites for the attachment of the pectoralis major, teres major, and latissimus dorsi mm.
the lateral lip of the intertubercular sulcus is continuous inferiorly with this large V-shaped structure on the lateral surface of the humerus midway along its length, which is where the deltoid muscle inserts onto the humerus.
one of the most important features of the proximal end of the humerus. this region is oriented in the horizontal plane between the expanded proximal part of the humerus (head, anatomical neck, and tubercles) and the narrower shaft. the axillary n. and the posterior circumflex humeral a., which pass into the deltoid region from the axilla, do so immediately posterior to this structure.
the 3 joints in the shoulder complex:
occurs between the proximal end of the clavicle and the
manubrium of sternum
together with a small part of the first costal cartilage. it's synovial and saddle-shaped. the articular cavity is completely separated into 2 compartments by an articular disc. it allows movement of the clavicle, predominantly in the anteroposterior and vertical planes, although some rotation also occurs.
anterior and posterior sternoclavicular ligaments
the sternoclavicular joint is surrounded by a joint capsule and is reinforced by 4 ligaments:
links the ends of the 2 clavicles to each other and to the superior surface of the manubrium of sternum
is positioned laterally to the joint and links the proximal end of the clavicle to the first rib and related costal cartilage
a small synovial joint between an oval facet on the medial surface of the acromion and a similar facet on the acromial end of the clavicle. it allows movement in the anteroposterior and vertical planes together with some axial rotation.
the acromioclavicular joint is surrounded by a joint capsule is reinforced by:
a small ligament that is superior to the joint and passing between adjacent regions of the clavicle and acromion
a large ligament which is not directly related to the joint, but reinforces it and is an important strong accessory ligament, providing much of the weight-bearing support for the upper limb on the clavicle and maintaining the position of the clavicle on the acromion. it spans the distance btw the coracoid process of the scapula and the inferior surface of the acromial end of the clavicle.
coracoclavicular ligament is comprised of an anterior ______ (which attaches to the trapezoid line on the clavicle) and a posterior _____ (which attaches to the related conoid tubercle).
a synovial ball and socket articulation between the head of the humerus and the glenoid cavity of the scapula. it is multiaxial with a wide range of movements provided at the cost of skeletal stability.
long head of the triceps brachii
Joint stability at the glenohumeral joint is provided by the ______ muscles, ____, related bony processes, and extrascapular ligaments.
head of humerus
the articular surfaces of the glenohumeral joint
a fibrocartilaginous collar that deepens and expands peripherally the glenoid cavity and attaches to the margin of the fossa. superiorly, this labrum is continuous with the tendon of the long head of the biceps brachii mm, which attaches to the supraglenoid tubercle and passes through the articular cavity superior to the head of the humerus.
the synovial membrane of the glenohumeral joint is loose inferiorly. this redundant region of synovial membrane and related fibrous membrane accommodates ____ of the arm.
subtendinous bursa of subscapularis
bursae formed by synovial membrane which lies between the subscapularis muscle and the fibrous membrane
subacromial or subdeltoid bursa
bursae between the acromion (or deltoid m) and supraspinatus m (or joint capsule)
superior, middle, and inferior glenohumeral ligaments
thickening of the fibrous mb of the joint capsule anterosuperiorly in 3 locations which pass from the superomedial margin of the glenoid cavity to the lesser tubercle and inferiorly related anatomical neck of the humerus
thickening of the fibrous mb of the joint capsule superiorly btw the base of the coracoid process and the greater tubercle of the humerus
transverse humeral ligament
thickening of the fibrous mb of the joint capsule between the greater and lesser tubercles of the humerus; this holds the tendon of the long head of the biceps brachii m in the intertubercular sulcus.
rotator cuff muscles
stabilize and hold the head of the humerus in the glenoid cavity of teh scapula without compromising the arm's flexibility and range of motion.
(3) teres minor
the rotator cuff muscles
the route through which structures pass between the base of the neck and the posterior scapular region. it is formed by the suprascapular notch of the scapula and the
transverse superior scapular ligament
, which converts the notch into a foramen.
provides a passageway for nerves and vessels passing between more anterior regions (axilla) and posterior scapular regions.
(1) teres minor (inferior margin)
(2) humerus (surgical neck)
(3) teres major (superior margin)
(4) long head of triceps brachii (lateral margin)
boundaries of the quadrangular space
(1) axillary n.
(2) posterior circumflex humeral a.
contents of the quadrangular space
an area of communication between the axilla and the posterior scapular region. when viewed from the posterior scapular region, the triangular space is formed by: long head of the triceps brachii, teres major, and teres minor.
(1) teres minor (inferior margin)
(2) teres major (superior margin)
(3) long head of triceps brachii (lateral margin)
boundaries of the triangular space
(1) long head of triceps brachii (lateral margin)
(2) humerus (shaft)
(3) teres major (inferior margin)
boundaries of the triceps hiatus
(1) circumflex scapular a.
contents of the triangular space
(1) radial n.
(2) profunda brachii a.
contents of the triceps hiatus
because this space is below the inferior margin of the teres major, which defines the inferior boundary of the axilla, this area serves as a passageway between the anterior and posterior compartments of the arm and btw the posterior compartment of the arm and the axilla.
originates in the base of the neck from the superior trunk of the brachial plexus. it passes posterolaterally from its origin, through the suprascapular foramen to reach the posterior scapular region, where it lies in plane between bone and muscle. it innervates the supraspinatus mm, then passes through the greater scapular notch, between the root of the scapular spine and the glenoid cavity, to terminate in and innervate the infraspinatus muscle.
originates from the posterior cord of the brachial plexus. it exits the axilla by passing through the quadrangular space in the posterior wall of the axilla and enters the posterior scapular region. together with the posterior circumflex humeral artery and vein, it is directly related to the posterior surface of the surgical neck of the humerus. it innervates the deltoid and teres minor muscles.
originates in the base of the neck as a branch of the thyrocervical trunk, which in turn, is a major branch of the subclavian artery. it normally enters the posterior scapular region superior to the suprascapular foramen, whereas the nerve passes through the foramen. It supplies the supraspinatus and infraspinatus mm.
posterior circumflex humeral artery
originates from the third part of the axillary artery in the axilla. with the axillary nerve, they leave the axilla through the quadrangular space in the posterior wall and enter the posterior scapular region. the vessel supplies the related muscles and the glenohumeral joint.
circumflex scapular artery
a branch of the subscapular artery that also originates from the third part of the axillary artery in the axilla. it leaves the axilla through the triangular space and enters the posterior scapular region, passes through the origin of the teres minor muscle, and forms anastomotic connections with other arteries in the region.
major abductor of the arm - abducts arm beyond initial 15 degrees done by supraspinatus.
clavicular fibers assist in flexing the arm; posterior fibers assist in extending the arm
elevates the scapula
initiation of abduction of the arm to 15 degrees at glenohumeral joint
external rotation of arm
external rotation of arm
internal rotation, extension, adduction of arm
long head of triceps brachii
extension of the forearm at the elbow joint.
accessory adductors and extensor of the arm at the glenohumeral joint.