Spaces Of Hand

Spaces Of Hand

Question 1. Write a short note on dorsal digital expansion.
Answer:

Each tendon of extensor digitorum flattens to form an aponeurotic expansion over the dorsal aspect of the MCP joint, which covers the dorsum and sides of the proximal phalanx like a hood. At the PIP joint, the aponeurotic expansion divides into three slips: a central slip and two collateral slips. The central slip is attached to the base of the middle phalanx, and the two lateral slips join each other to form a single slip which is attached to the dorsal aspect of the base of the distal phalanx.

Spaces of the Hand Anatomy

The margins of the extensor expansion are reinforced by intrinsic muscles of the hand – the interossei and lumbrical muscles.

Functional significance of the dorsal digital expansion

The intrinsic muscles arising from the palmar aspect of the hand and inserting along the dorsal aspect of the fingers can have a unique function in that they flex the metacarpophalangeal (MP) joints, and extend the proximal and distal interphalangeal (i.e., PIP and DIP) joints.

Question 2. What are the fascial spaces of the hand?
Answer.

Several fascial spaces in the region of the hand are formed due to the arrangement of fasciae and fascial septa. These are as follows.

Palmar spaces

• Midpalmar space
• Thenar space
• Pulp space

Anatomical Spaces of the Hand

Dorsal spaces

• Dorsal subcutaneous space
• Dorsal subaponeurotic space

Parona’s space

• Fascial space in front of the distal forearm