Finger joints move in specific ways at the metacarpophalangeal (MCP) joint, also known as the knuckle joint. These movements allow for the dexterity and flexibility of the hand. Here's a breakdown:
Movements at the Metacarpophalangeal (MCP) Joint
The MCP joint is where the fingers connect to the hand. This joint permits the following primary movements:
- Flexion:
- This is the movement of bending the finger towards the palm of the hand.
- Example: Making a fist involves flexing all your fingers at the MCP joints.
- Think of it as closing your hand.
- Extension:
- This is the opposite of flexion, moving the finger away from the palm.
- Example: Straightening your fingers after making a fist involves extending them at the MCP joints.
- Think of it as opening your hand.
- Adduction:
- This movement is bringing the fingers towards the middle finger.
- Example: If you were to bring your index finger towards your middle finger, that is adduction.
- Think of it as squeezing your fingers together.
The finger movements at the MCP joints are crucial for grasping, holding, and manipulating objects.
Summary of Finger Joint Movements
| Movement | Description | Example |
|---|---|---|
| Flexion | Moving the base of the finger towards the palm | Making a fist |
| Extension | Moving the base of the finger away from the palm | Straightening your fingers |
| Adduction | Moving the fingers toward the middle finger | Squeezing fingers together |
These movements, while seemingly simple, allow for the complex and precise manipulations that the human hand is capable of.
