Metacarpals

Definition

The metacarpals are a group of five bones located in the palm of the hand, connecting the wrist to the fingers. These bones play a crucial role in the structure and function of the hand, providing a stable foundation for the fingers and enabling various hand movements.

5 Must Know Facts For Your Next Test

1. The metacarpals are classified as long bones, with a shaft (diaphysis) and two ends (epiphyses).
2. The metacarpals are numbered from the thumb (1st metacarpal) to the little finger (5th metacarpal).
3. The proximal ends of the metacarpals articulate with the carpals, forming the carpal-metacarpal joints, while the distal ends articulate with the phalanges.
4. The metacarpals provide attachment points for various muscles, including the interossei, lumbrical, and thenar and hypothenar muscles, which are essential for hand dexterity and grip strength.
5. The development of the metacarpals is closely linked to the development of the appendicular skeleton, as they arise from the same embryonic precursors.

Review Questions

• Explain the role of the metacarpals in the classification of bones within the skeletal system.
  • The metacarpals are classified as long bones, which are characterized by a diaphysis (shaft) and two epiphyses (ends). This classification is important as it reflects the structural and functional properties of the metacarpals, including their ability to withstand compressive and tensile forces during hand movements and their role in the overall architecture of the hand and upper limb.
• Describe the anatomical relationships between the metacarpals, carpals, and phalanges, and how these relationships contribute to the divisions of the skeletal system.
  • The metacarpals are part of the appendicular skeleton, specifically the bones of the upper limb. They connect the carpals of the wrist to the phalanges of the fingers, forming a crucial link in the skeletal structure of the hand. This integration of the metacarpals with the carpals and phalanges is essential for the hand's dexterity, flexibility, and overall function, and it highlights the interdependence of the different divisions of the skeletal system in enabling complex movements and activities.
• Analyze the role of the metacarpals in the development of the appendicular skeleton, and explain how this developmental process contributes to the structure and function of the hand.
  • The metacarpals arise from the same embryonic precursors as the other bones of the appendicular skeleton, including the carpals and phalanges. This shared developmental origin allows for the coordinated growth and integration of these bones, ensuring the proper formation and alignment of the hand's skeletal structure. The metacarpals play a crucial role in this developmental process, providing a stable foundation for the fingers and enabling the hand's dexterity and versatility in performing a wide range of tasks. The developmental relationships between the metacarpals and other appendicular bones are essential for the hand's overall function and adaptation to various physical demands.

Related terms

Carpals:

The carpals are a group of eight small bones located in the wrist, proximal to the metacarpals, that facilitate the movement and stability of the hand.

Phalanges:

The phalanges are the bones that make up the fingers, with each finger consisting of three phalanges (except for the thumb, which has two).

Interosseous Muscles: The interosseous muscles are a group of small muscles located between the metacarpal bones, responsible for the fine motor movements and stability of the fingers.