What are the thumb joints?

Interphalangeal Joint (IP)

What are the thumb joints called?

The thumb basal joint, also known as the carpometacarpal (CMC) joint, is a specialized saddle-shaped joint that is formed by a small wrist bone (trapezium) and the first of the three bones in the thumb (metacarpal).

What is the joint at the base of the thumb called?

Thumb arthritis is common with aging and occurs when cartilage wears away from the ends of the bones that form the joint at the base of your thumb — also known as the carpometacarpal (CMC) joint.

How many joints are there in a thumb?

Each thumb has two joints. The surfaces of the bones where they meet to form joints are covered with a layer of cartilage, which allows them to glide smoothly against one another as they move.

What is the second joint of the thumb called?

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.

What is the top thumb joint called?

Interphalangeal Joint (IP)

The thumb digit has only two phalanges (bones) so it only has one joint. 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.

What is an MP joint?

The large joints in the hand at the base of each finger are known as the metacarpophalangeal (MP, or MCP) joints. They act as complex hinge joints and are important for both power grip and pinch activities.

Does the thumb have 3 joints?

The final bone, which is smallest and furthest from the hand, is called the distal phalanx. The thumb does not have a middle phalanx. Each finger contains 3 joints, more commonly known as knuckles. The thumb has two knuckle joints.

What type of joint is the finger joint?

Metacarpophalangeal Joint (MCP): The MP joint is where the hand bone meets the finger bone, referred to as the “knuckle.” These joints are very important, allowing us to bend/flex and spread our fingers.

What is the CMC thumb joint?

The CMC joint (also called the basal joint) at the base of the thumb is commonly affected by arthritis. It is the thumb joint located deep in the heel of the palm where the thumb metacarpal joins with a wrist bone called the trapezium.

What is DIP and PIP joints?

The PIP and DIP joints are hinge joints between proximal and middle phalanges and between the middle and distal phalanges respectively.

Is the CMC joint part of the wrist?

The carpometacarpal (CMC) joints are five joints in the wrist that articulate the distal row of carpal bones and the proximal bases of the five metacarpal bones.

What is a cartilage?

Cartilage a strong and smooth substance made up of “chondrocytes,” or specialized cartilage cells, that produce a matrix of collagen, proteoglycans (a special type of protein) and other non-collagenous proteins. These materials help cartilage attract water and give it its shape and specific properties.

What is the first joint of the thumb?

The 1st CMC (carpometacarpal) joint is a specialized saddle-shaped joint at the base of the thumb. The trapezium carpal bone of the wrist and the first metacarpal bone of the hand form the 1st CMC or thumb basal joint.

Is the thumb a hinge joint?

ANATOMY. The MP joint of the thumb is primarily a hinge joint. Flexion and extension comprise the primary arc of motion. Pronation-supination and abduction-adduction are considered secondary arcs of motion at this joint.

Is the thumb a finger?

The thumb, and the rest of the fingers, are appendages or digits of the hand. While the thumb is distinctly different from the other four fingers, many medical professionals consider it a finger due to differences in size, bones, joints, and function.

Is the thumb a saddle joint?

The thumb basal joint, also known as the carpometacarpal (CMC) joint, is a specialized saddle-shaped joint that is formed by a small wrist bone (trapezium) and the first of the three bones in the thumb (metacarpal).

Are fingers hinge joints?

Hinge joints, such as in the fingers, knees, elbows, and toes, allow only bending and straightening movements.

What joints are saddle joints?

Saddle joints are also known as sellar joints. These highly flexible joints are found in various places in the body, including the thumb, shoulder, and inner ear.

Do we have 8 or 10 fingers?

Ask an evolutionary biologist, however, and you're likely to get a much simpler answer: We have 10 fingers and 10 toes because, somewhere in our species' past Darwinian wanderings, those numbers gave us an evolutionary advantage. Had events tumbled differently, we might have eight fingers and twelve toes.

What is a CMP joint?

The carpometacarpal joints of the fingers are synovial plane joints that serve as the articulation between the carpals and the metacarpals and allow the bases of the metacarpal bones to articulate with one another. From: Atlas of Common Pain Syndromes (Fourth Edition), 2019.

What is thumb MCP?

The metacarpophalangeal (MCP) joints are located where the hand's fingers and thumb meet the palm. They are commonly known as large knuckles.

What is the 3rd MCP joint?

The capsule of the metacarpophalangeal joint is reinforced on all sides. It extends from the metacarpal neck to the base of the proximal phalanx. Dorsally it is reinforced by the common extensor tendon and volarly by the volar plate and the deep transverse metacarpal ligament (DTML).

What are 3 types of cartilage?

There are three types of cartilage: hyaline, fibrous, and elastic cartilage. Hyaline cartilage is the most widespread type and resembles glass. In the embryo, bone begins as hyaline cartilage and later ossifies. Fibrous cartilage has many collagen fibers and is found in the intervertebral discs and pubic symphysis.

Which is a hinge joint?

[3][4] The hinge joints of the body include the elbow, knee, interphalangeal (IP) joints of the hand and foot and the tibiotalar joint of the ankle.