upper arm osteology Flashcards
what does the head of the humerus do?
Articulates with the scapula at the glenohumeral joint
Greater tubercle, where is it and what does it do?
Lies just lateral and distal to the anatomic neck and provides attachments for the supraspinatus, infraspinatus, and teres minor muscles
Lesser Tubercle, where is it and what does it do?
Lies on the anterior medial side of the humerus, just distal to the anatomic neck, and provides an insertion for the subscapularis muscle
Bicipital Groove, where is it and what does it do?
- Lies between the greater and lesser tubercles, lodges the tendon of the long head of the biceps brachii muscle, and is bridged by the transverse humeral ligament.
- Provides insertions for the pectoralis major on its lateral lip, the teres major on its medial lip, and the latissimus dorsi on its floor
Surgical Neck, whats significant?
Is a narrow area distal to the tubercles that is a common site of fracture and is in contact with the axillary nerve and the posterior humeral circumflex artery
what is a colles fracture? what happens?
Fractures of the Distal End of the Radius (from breaking falls) are common and are referred to as Colle’s fracture. The Styloid Process of the Ulna is often also avulsed in this situation.
Dinner fork!
what is a humeral trochlea?
articulates with ulna
what is a humeral capitulum?
articulates with radius
Lateral Epicondyle, what attaches to it?
radial collateral ligament
supinator and extensor muscles of the forearm
Medial Epicondyle, what attaches to it?
groove on the back for the ulnar nerve and superior ulnar collateral artery. Provides attachment sites for the ulnar collateral ligament, the pronator teres, and the common tendon of the forearm flexor muscles
how many carpal bones are there?
Some Lovers Try Positions that they cant handle
Scaphoid
Lunare
Triqutrum
Pisiform Trapezium Trapezoid Capitate Hamate
Where is the olecranon, what does it attach to?
ulna, triceps tendon
what is radial notch of the ulna?
head of radius goes in here
what is the most commonly broken bone in the hand, what happens?
The Scaphoid is the most commonly fractured Carpal Bone, and is usually the result of trying to break a fall, often the fracture in not visible on a radiograph and therefore misdiagnosed as a severe sprain. The distal fragment of bone is susceptible to avascular necrosis since it is usually separated from its blood supply
what is the radial tuberosity?
Radius, biceps brachii tendon attatches
Styloid process of the radius, what is it?
distal end of the radius and is approximately 1 cm distal to that of the ulna and provides insertion of the brachioradialis muscle
Can be palpated in the proximal part of the anatomic snuffbox between the extensor pollicis longus and brevis tendons
what are the main landmarks of the anterior scapula?
costal surface is anterior
- subscapular fossa is surface
- glenoid cavities separate tubercles
- suprascapular notch: artery, ligament
- coracoid process
what are the main landmarks of the posterior scapula?
- scapular spine
- deltoid tuberosity
- acromion
- greater scapular notch: connects supraspinous and infraspinous fossa
what does acromion do?
scapula articulates with clavicle
why are there two necks of the humerus?
one is for surgeons, lower, and one is anatomical
surgical neck fracture is much worse
Fracture of surgical neck?
may injure the axillary nerve and the posterior humeral circumflex artery as they pass through the quadrangular space
Fracture of the shaft of the humerus?
may injure the radial nerve and deep brachial artery in the spiral groove.
what is a supercondylar fracture?
a fracture of the distal end of the humerus; it is common in children and occurs when the child falls on the outstretched hand with the elbow partially
flexed and may injure the median nerve
Fracture of the medial epicondyle?
may damage the ulnar nerve. This nerve may be compressed in a groove behind the medial epicondyle “funny bone,” causing numbness.
