Upper Limb Flashcards
1
Q
What percentage of total body weight does the human skeleton account for?
A
20% of total body weight
2
Q
How many bones are there in the human skeleton ?
A
206-214 bones
3
Q
Name the largest and smallest bones in the human skeleton.
A
Largest bone - Femur
Smallest Bone - Ear Ossicles (stapes, maleus and incus)
4
Q
How many bones are there in the upper limb?
A
32 bones in each upper limb (32x2)
5
Q
Name the bones of the upper limb
A
Clavicle Scapula Humerus (Upper arm) Radius Ulna 8 Carpal Bones (Wrist) 5 Metacarpal Bones (Hand) 14 Phalanges (Fingers)
6
Q
List the peculiarities of the clavicle
A
- It is the only long bone situated horizontally in the body
- It is subcutaneous throughout
- It is the first bone to ossify
- It is the only long bone to ossify in the membrane
- It is the only long bone which ossifies from two primary centres of ossification
- It has no medullary cavities
- It is occasionally pierced by the middle suprascapular nerve
- It is weakest at the junction between the medial 2/3 and lateral 1/3
7
Q
Describe Ossification of the clavicle
A
- Two primary centres for the shaft - appear around the 5th -6th week and soon fuse at the 45th day
- Secondary centre for the medial end appear during the 15th-17th year and fuse with the shaft during the 21-22 years
- Occasionally there may be a secondary centre for the acromial end
8
Q
Name the muscles of attachment and structures that can be seen on the superior view of the clavicle.
A
- Sternocleidomastoid (on medial 2/3)
- Pectoralis major (on medial 2/3)
- Trapezius (on lateral 1/3)
- Deltoid (on lateral 1/3)
- Capsule of sternoclavicular joint (at the medial end)
9
Q
Name the muscles of attachment and structures that can be seen on the inferior view of the clavicle.
A
- Deltoid
- Trapezius
- Subclavius
- Sternohyoid
- Pectoralis Major
- Capsule of acromioclavicular joint (at acromial/lateral end)
- Trapezoid and Conoid parts of the coracoclavicular ligament
- Costoclavicular ligament
