- The interphalangeal (IP) joints of the hand are located between the phalanges of the fingers (including the thumb).
- There is one interphalangeal joint in the thumb.
- There are two interphalangeal joints in each of the other fingers (#2-5; index, middle, ring, little): proximal interphalangeal (PIP) joints and distal interphalangeal (DIP) joints.
- The interphalangeal joints are synovial, diarthrotic, uniaxial, hinge joints.
- They allow:
- flexion/extension of the fingers in the sagittal plane.
NOTES:
- Proximal interphalangeal (PIP) joints are located between proximal and middle phalanges.
- Distal interphalangeal (DIP) joints are located between middle and distal phalanges.
- Because the thumb has only two phalanges, it has only one interphalangeal joint.
- Singular of the word phalanges is phalanx. There is no word phalange.
![Anterior view of the interphalangeal joints on the right side of the body (as well as other joints of the wrist and hand).](https://learnmuscles.com/wp-content/uploads/2020/11/08-Hand-RU-anterior-6551-fingers-down-2-614x1024.jpg)
Anterior view of the interphalangeal joints on the right side of the body (as well as other joints of the wrist and hand).
![Posterior view of the interphalangeal joints on the right side of the body (as well as other joints of the wrist and hand).](https://learnmuscles.com/wp-content/uploads/2020/11/08-Hand-RU-posterior-6612-2-580x1024.jpg)
Posterior view of the interphalangeal joints on the right side of the body (as well as other joints of the wrist and hand).
![Bones of the wrist and hand in the posture of a fist on the right side.](https://learnmuscles.com/wp-content/uploads/2020/11/08-Hand-FDP-6776-1024x1024.jpg)
Bones of the wrist and hand in the posture of a fist on the right side.