Bones & Joint Features

Question 1

Give an example of each of the following bony features:
i Epicondyle
ii Articular surface
iii spine

Answer 1

i. Epicondyle –a raised rounded bony prominence on a condyle of a long bone e.g medial epicondyle of the humerus.
ii. Articular surface- the surface of a bone that joins to another bone, found at proximal and distal ends of a bone and covered in hyaline cartilage. Eg head of femur which articulates with acetabulum
iii. Spine – a sharp raised prominence of a bone for the attachment of muscles and ligaments e.g spine of scapula

Question 2

Briefly explain the structure and function/ purpose of the following:
i Articular capsule
ii Synovial fluid
iii Fat pad

Answer 2

i. Articular capsule- sleeve of white fibrous connective tissue surrounding the joint, enclosing the bone ends within it. It protects the joint, provides stability and holds bones together, is a base layer for the synovial membrane and prevents escape of synovial fluid.
ii. Synovial fluid – viscous fluid released by the synovial membrane, it fills all available space in the joint nourishes the articular cartilage, lubricates it.
iii. Fat pad-pad of fat tissue may be imposed between synovial membrane and the capsule to cushion certain movements.

Question 3

Name three (3) of the most common classifications of bones

Answer 3

i. Long bones, short bones, sesamoid bones, flat bones, irregular bones

Question 4

Name the three (3) types of joints in the structural classification of joints.

Answer 4

Synovial joints, fibrous joints, cartilaginous joints

Question 5

List three (3) similarities between the bony structure of the foot and the hand.

Answer 5

i. Proximal part of both consists of short bones – only allow small gliding movements to transmit forces from bones of arm/leg.
ii. Middle part consisting of long bones metatarsals and metacarpals
iii. Each of the lateral 4 digits are composed of 3 phalanges (proximal, middle, distal) while the medial digit (thumb in the hand and the great toe in the foot) consists of 2 phalanges (proximal and distal).

Question 6

List two (2) differences between the bony structure of the foot and hand

Answer 6

i. The 1st Metacarpal bone directs at an angle away from rest of hand, is highly mobile whereas the metatarsal in the foot is relatively immobile, in line with other metatarsals and transmits forces.
ii. In the hand, the phalanges are much longer, while in the foot the phalanges are much shorter

Question 7

Explain how these differences may relate to the functions of the foot OR the hand.

Answer 7

The bones in the hands form long fingers and a mobile opposing thumb to allow for dexterity, gripping and fine movements whereas the foot is adapted to support the weight of the body during locomotion and standing, so its relative inflexibility of its bone structure makes it well suited for this.