The hand in the human body is made up of the wrist, palm, and fingers. The most flexible part of the human skeleton, the hand enables us to perform many of our daily activities. When our hand and wrist are not functioning properly, daily activities such as driving a car, bathing, and cooking can become impossible.

The hand’s complex anatomy consists of

It is important to understand the normal anatomy of the hand in order to learn about diseases and conditions that can affect our hands.

Skeletal Anatomy

The wrist is comprised of 8 bones called carpal bones. These wrist bones connect to 5 metacarpal bones that form the palm of the hand. Each metacarpal bone connects to one finger or a thumb at a joint called the metacarpophalangeal joint, or MCP joint. This joint is commonly referred to as the knuckle joint.

The bones in our fingers and thumb are called phalanges. Each finger has 3 phalanges separated by two joints.

The first joint, closest to the knuckle joint, is the proximal interphalangeal joint or PIP joint. The second joint nearer the end of the finger is called the distal interphalangeal joint, or DIP joint. The thumb in the human body only has 2 phalanges and one interphalangeal joint.

Soft Tissue Anatomy

Our hand and wrist bones are held in place and supported by various soft tissues. These include:

Nerves

Nerves are responsible for carrying signals back and forth from the brain to muscles in our body, enabling movement and sensation such as touch, pain, and hot or cold. The three main nerves responsible for hand and wrist movement all originate at the shoulder area and include the following:

Blood Vessels

The two main vessels of the hand and wrist are

Bursae

Bursae are small fluid filled sacs that decrease friction between tendons and bone or skin. Bursae contain special cells called synovial cells that secrete a lubricating fluid. When this fluid becomes infected, a common painful condition known as Bursitis can develop.

Normal Movement

Biomechanics is a term to describe movement of the body. The fingers of the hand permit the following movements at the metacarpophalangeal joint (MCP) or knuckle joint.

Biomechanics of the wrist include the following:

The thumb performs different movements at three separate joints. The carpometacarpal joint is where the wrist bones, carpals, meet the metacarpals, the bones in the palm of the hand. At this articulation, the following movements can be performed:

The following movements occur at the metacarpophalangeal joint or MCP joint at the base of the thumb:

At the interphalangeal joint of the thumb or IP joint, the following movements can be performed:

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