Lecture 3.2 Flashcards
When are knee and elbow joints formed during embryonic development?
Limbs start out as limb buds formed by somites. 6th embryonic week marks aflexia formation of the elbow and knee joints.
What happens to leg (relative to arms) during embryonic development?
Leg rotates during embryological development.
How are limbs studied?
Limbs divided into regions.
What structures form the pectoral girdle?
Clavicle meets with scapula to form pectoral girdle.
What kind of bone is the sternum? What kind of ossification does the sternum undergo?
Flat bone formed Intramembranous ossification
What notches does the manubrium contain?
Jugular notch Clavicular notch Costal notch
What is the function of the costal notch of the manubrium?
Costal notch attaches to the first rib
What part of the manubrium does the clavicle connect to?
Sternoclavicular joint occurs at clavicular notch.
What kind of bone is the clavicle?
Long bone
What kind of ossification does the clavicle undergo?
proximal and distal ends undergo endochondral ossification and shaft undergoes intramembranous ossification.
Does the clavicle have a medullary cavity? Does it have bone marrow?
No Yes
What is the shape and attachment of the medial end?
Rounded sternal end. This meets the manubrium of the sternum.
What is the shape and attachment of the lateral end of the clavicle?
Lateral clavicle end is flatter and meets with the acromion process.
What is the function of the clavicle?
Clavicle acts as an S shaped strut which allows the clavicle to take the forces which acts on the upper limb and dissipates them to the midline of the body. (can be thought of as a spork (spoke, not spork you dimwit) in a wheel)
What is unique about the clavicle’s ossification?
Clavicle is one of the earliest bones to start ossification and one of the last bones to complete ossification. (clavicle can be used to age skeletons)
Where is the most common site of fracture of the clavicle?
Between lateral 1/3 and medial 2/3. Common injury during a FOOSH.
What happens after the clavicle breaks? What happens if it isn’t repaired?
The sternomastoid pulls the medial part upwards and the deltoid muscle pulls the lateral side of the clavicle downwards. If bone isn’t fixed the fusion of the clavicle becomes crooked.
Where does the scapula sit?
Scapula lies on posterior side of rib cage and glenoid fossa faces laterally.
What are the 3 borders of the scapula?
Superior border Medial border Lateral border
What are the fossae of the scapula?
3 fossae scapula: Infraspinous fossa supraspinous fossa subscapular fossa
What structures form the suprascapular foramen?
Supra scapular notch Transverse scapular ligament.
Which part of the scapula contains the suprascapular nerve?
The suprascapular foramen on the superior border.
Where does the suprascapular artery run relative to the suprascapular foramen?
Above the transverse scapular ligament.
Where are the coracoid process and the acromion process relative to each other?
Coracoid process projects anteriorly. Acromion process projects as a continuation of the spine posteriorly.
What structures typically get fractured on the scapula?
Acromion process Coracoid process
What kind of bone is the humerus?
Long bone
What shape is the head of the humerus and what are the benefits of this structure?
Head of humerus is 1/3rd of a sphere. This allows humerus to fit into glenoid socket and this allows the shoulder to be very mobile.
Where is the anatomical neck of the humerus?
Anatomical neck of the humerus separates tubercles from head.