Interphalangeal Joint (IP) The thumb interphalangeal (IP) joint is similar to the distal interphalangeal (DIP) joint in the fingers. The IP joint in thumb is located at the tip of the finger just before the fingernail starts.
The bone under the nail that makes up the tip of the thumb is called the distal phalanx. The next bone is called the proximal phalanx. The distal phalanx and proximal phalanx connect via the interphalangeal (IP) joint, which allows you to bend the tip of your thumb.
The skeleton of the thumb consists of the first metacarpal bone which articulates proximally with the carpus at the carpometacarpal joint and distally with the proximal phalanx at the metacarpophalangeal joint. This latter bone articulates with the distal phalanx at the interphalangeal joint.
The first bone — the distal phalange — extends from the tip of the thumb to the knuckle. The second bone — proximal phalange — then extends from the knuckle to the base of the thumb. The thumb then connects to the hand bone, or thumb metacarpal.
The thumb joint, called the carpometacarpal joint, is made up of a bone in your wrist called the trapezium, and a long bone at the base of your thumb called a metacarpal.
In the thumb, the most common site for arthritis to develop is in the basal joint at the base of the thumb — also known as the thumb carpometacarpal (CMC) joint. Although there are several types of arthritis, the one that most often affects the basal joint is osteoarthritis (degenerative, or wear-and-tear, arthritis).
There are several causes of thumb pain including: (1) trigger thumb, (2) arthritis, (3) tendonitis, (4) carpal tunnel syndrome, and (5) skier's thumb.
Anterior interosseous nerve syndrome: Damage to the anterior interosseous nerve (a motor branch of the median nerve) causes weakness or paralysis in the thumb and index finger. It can affect your ability to pinch items between your thumb and index finger. It also causes wrist pain.
The area of skin between the thumb and the index finger is often call the "thenar webspace". What the "webspace" looks like when a child is performing fine motor tasks is often a good indicator of muscle strength and fine motor control.
The parts of the hand include, Thumb, Index finger, Middle finger, Ring finger, Little finger, Palm, Wrist, Knuckle, Fingernail.
Thenar eminence - fleshy part at the base of the thumb, made up of 3 muscles which control the movements of the thumb.
The anatomical descriptors of the thumb may be defined as: Dorsal: in the same plane as the thumbnail. Volar: in the same plane as the pulp of the thumb. Ulnar: on the side of the thumb toward the hand at a right angle to the plane of the thumbnail.
Luo says. “You may also notice a little bump at the base of your thumb,” he adds, explaining that this would be a bone spur, or a projection that develops along joints as a result of inflammation, including osteoarthritis. Other symptoms may include the following: Swelling and tenderness at the base of the thumb.
Heberden's nodes are bony growths that can develop on the finger joints of people with osteoarthritis. They usually affect the joints nearest the fingertips and can cause pain and stiffness.
The entire central fleshy part of the hand is called the palm. But the area below the thumb joint is comparatively more fleshy and is termed as thenar prominence (ball of the thumb). Similarly, the fleshy mass below the little finger is called the hypothenar eminence.
What is the trapezium? The trapezium is the cube-shaped bone in your wrist that is joined to the base of your thumb (trapeziometacarpal joint).
*Flagina -the awkward piece of skin between your thumb and pointer finger*…
Scaphotrapeziotrapezoid Joint (STT)
The scaphotrapeziotrapezoid joint is at the base of the thumb in the wrist. It is made up of three wrist bones, the scaphoid, the trapezium, and the trapezoid. The scaphoid rotates at this joint as you move the wrist. This joint can become arthritic.
Carpal Tunnel Syndrome
If the carpal tunnel passageway in your wrist becomes inflamed, it can put pressure on nerves that can lead to pain, numbness, and even affect your grip.
A numb thumb is most often caused by a problem with the nerves that go to the hand. It's less likely, but other causes like strokes, diabetes, and nutritional deficiencies could cause numbness in the thumb—though, a person will usually have other symptoms too if they have these conditions.
Thumb numbness can have many possible causes. This may include injury to any nearby components of the arm, wrist, or hand, temporary nerve compression from arm positioning, nerve root compression in the neck or nerve compression in the wrist (carpal tunnel syndrome), or even some systemic illnesses.
There are many potential causes for thumb pain, but the three most common conditions that tend to develop are 1) arthritis, 2) trigger thumb, and 3) De Quervain tenosynovitis. The location of the pain and symptoms can help determine the exact cause of your pain and what your best treatment option may be.