Quick Answer: The human wrist has 8 carpal bones, arranged in two rows of four between the forearm and the hand. They are the scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate, and hamate.
The 8 Carpal Bones of the Wrist
| Row | Bones |
|---|---|
| Proximal row (nearer the forearm) | Scaphoid, lunate, triquetrum, pisiform |
| Distal row (nearer the hand) | Trapezium, trapezoid, capitate, hamate |
Keep reading for what each row does, which carpal bone is most commonly fractured, and how the wrist fits into the rest of the hand’s bone count.
What the Two Rows of Carpal Bones Do
The proximal row sits closer to the forearm and connects to the radius bone, forming the main wrist joint that allows the hand to bend up, down, and side to side. The distal row sits closer to the palm and connects to the metacarpal bones of the hand, transferring force from the wrist into the base of each finger and thumb. Between them, the two rows let the wrist move through a wide range of motion while still transmitting grip strength efficiently.
The Scaphoid: The Most Commonly Fractured Carpal Bone
The scaphoid, on the thumb side of the proximal row, is the carpal bone broken most often, typically from falling onto an outstretched hand. It’s also notorious for healing slowly, since much of its blood supply enters from one end, and a fracture near the opposite end can be starved of blood flow. That’s why a suspected scaphoid fracture is treated cautiously even when an initial X-ray looks normal.
How the Wrist Fits Into the Hand’s Total Bone Count
The 8 carpal bones of the wrist are part of the larger count covered in our guide to how many bones are in the human hand, which totals 27 per hand once you add the 5 metacarpals and 14 finger and thumb bones. The wrist’s 8 bones alone make up nearly a third of that total, packed into a joint small enough to circle with two fingers.
Common Wrist Bone Conditions
Beyond fractures, the tight space the carpal bones form on the palm side, known as the carpal tunnel, is where the median nerve can become compressed, causing the numbness and tingling associated with carpal tunnel syndrome. Arthritis can also develop in the small joints between individual carpal bones, particularly after an old, poorly healed fracture changes how the bones line up and bear weight.
Frequently Asked Questions
8 carpal bones, arranged in two rows of four between the forearm and the hand.
Scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate, and hamate.
The scaphoid, usually from falling onto an outstretched hand. It’s also known for healing slowly due to its limited blood supply.
The 8 carpal bones are typically counted as part of the hand’s total 27 bones, alongside the 5 metacarpals and 14 finger and thumb bones.
A narrow passage formed by the carpal bones and a ligament on the palm side of the wrist, through which the median nerve passes. Compression here causes carpal tunnel syndrome.
Final Answer: How Many Bones Are in the Wrist
The wrist has 8 carpal bones, split into a proximal row that connects to the forearm and a distal row that connects to the hand. The scaphoid is the one most likely to break and the slowest to heal. Together with the rest of the hand, these 8 small bones give the wrist the combination of mobility and strength needed for everything from a firm handshake to a delicate grip.