Comprehensive Guide to Hand and Wrist Anatomy and Conditions

The human hand enables us to perform many of our daily activities such as driving, writing, and cooking. Yet all too often we take the ability to grip and grasp for granted, because we have been doing it all of our lives. Yet for anyone who has suffered from conditions or injuries to their hands and wrists, it can be extremely debilitating, uncomfortable, and painful. You deserve to use your hands and wrists without pain – we’re here to help.

To help you discuss hand and wrist conditions and treatment options with your surgeon, here’s a breakdown of the anatomy of the hand and wrist.

  • Anatomy
  • Conditions
  • Procedures

Hand & Wrist Anatomy

The hand is made up of the wrist, palm, and fingers, and consists of 27 bones, 27 joints, 34 muscles, more than  100 ligaments and tendons, and many blood vessels and nerves. 

Bones of the Hand

The wrist is composed of eight carpal bones, which attach to the radius and ulna to form the wrist joint, and the five metacarpal bones that form the palm of the hand. Each metacarpal bone connects to one finger at a metacarpophalangeal joint, also known as the knuckle. The joint closest to the knuckle is the proximal interphalangeal joint, and the joint closest to the end of the finger is the distal interphalangeal joint. Both act like hinges when the fingers bend and straighten.

The bones in our fingers and thumb are called phalanges. Each finger has three phalanges separated by two interphalangeal joints and the thumb has only two phalanges and one interphalangeal joint.

Articular cartilages are smooth material that act as shock absorbers and cushion the ends of bones at each of the 27 joints, allowing smooth movement of the hand.

Ligaments function to control the movement of the hand.

Muscles of the Hand

There are two types of muscles in the hand. 

  • Intrinsic muscles are small muscles that originate in the wrist and hand, and  are responsible for fine motor movements of the fingers.
  • Extrinsic muscles originate in the forearm or elbow, control the movement of the wrist and hand, and  are responsible for gross hand movements. Each finger has three extrinsic and three intrinsic muscles. The index and little finger each have an extra extrinsic extensor.

Ligaments of the Hand

Each finger joint has two collateral ligaments on either side, which stop the joints from bending sideways. The volar plate is the strongest ligament in the hand, and joins the proximal and middle phalanx on the palm side to prevent backward bending, hyperextension.

Tendons of the Hand

The extrinsic muscles are attached to finger bones through long tendons that extend from the forearm through the wrist. Flexor tendons on the palm side help in bending the fingers, while extensor tendons on top of the hand help straighten the fingers.

Nerves of the Hand

The three main nerves of the hand and wrist originate at the shoulder and travel down the arm to the hand: 

  • The ulnar nerve crosses the wrist through an area called Guyon’s canal and branches to provide sensation to the little finger and half of the ring finger. 
  • The median nerve crosses the wrist through a tunnel called the carpal tunnel, providing sensation to the palm, thumb, index finger, middle finger and part of the ring finger. 
  • The radial nerve runs down the thumb side of the forearm and provides sensation to the back of the hand from the thumb to the middle finger. 

Blood Vessels of the Hand

The main arteries are the ulnar and radial arteries, which supply blood to the front of the hand, fingers, and thumb. The ulnar artery travels next to the ulnar nerve through the Guyon’s canal in the wrist. The radial artery is the largest artery of the hand, traveling across the front of the wrist, near the thumb. Other blood vessels travel across the back of the wrist to supply blood to the back of the hand, fingers and thumb.

If you’re suffering from injuries, problems, or pain to your hand and wrist, let us help you get a grip on your condition — and get your back your comfort and quality of life.

Adult Forearm Fractures

Adult Forearm Fractures

The forearm is made up of 2 bones, namely, the radius and ulna. The primary function of your forearm is rotation i.e., the ability to turn your palm up and down. The fracture of the forearm affects the ability to rotate your arm, as well as bend and straighten the wrist and elbow.

Arthritis of the Hand and Wrist

Arthritis of the Hand and Wrist

Arthritis is an inflammatory condition of the joints. There are several types of arthritis and the most common type is osteoarthritis or wear-and-tear arthritis. Arthritis affects various joints in the body and the arthritis in the hand affects the joint at the base of the thumb.

Arthritis of the Thumb

Arthritis of the Thumb

The forearm consists of two bones, the radius and ulna. The radius is the larger of the two forearm bones, and the region towards the wrist is called the distal end. A fracture or break in the distal end of the radius bone is known as a distal radius fracture.

Bennett's Fracture

Bennett's Fracture

Bennet’s fracture is a break at the base of the first metacarpal bone (thumb bone) that meets the wrist at the first carpometacarpal (CMC) joint. The hand is composed of 3 types of bones: carpals or wrist bones, metacarpals or long hand bones, and phalanges or finger bones.

Boxer's Fracture

Boxer's Fracture

A boxer’s fracture is a break in the neck of the fifth metacarpal bone of the hand (below the pinky finger) close to the knuckle. The hand is composed of 3 types of bones: carpal or wrist bones, metacarpals or long hand bones, and phalanges or finger bones.

Carpal Tunnel Syndrome

Carpal Tunnel Syndrome

Carpal tunnel syndrome is a common, painful, progressive condition that is caused by compression of the median nerve at the wrist area.

De Quervain's Tendinosis

De Quervain's Tendinosis

The muscles and bones of your hand are connected by thick flexible tissue called tendons. Tendons are covered by a thin soft sheath of tissue known as synovium. Extensor pollicis brevis and abductor pollicis longus are two tendons located on the thumb side of the wrist.

Distal Radioulnar Joint (Druj) Arthritis

Distal Radioulnar Joint (Druj) Arthritis

Distal radioulnar joint (DRUJ) arthritis is an inflammatory condition characterized by gradual wearing away of the cartilaginous surface of the radioulnar joint resulting in significant pain, swelling, stiffness, and interference in the functioning of the wrist and/or arm.

Distal Radius Osteotomy to Correct Mal-Union (Crooked Painful Wrist)

Distal Radius Osteotomy to Correct Mal-Union (Crooked Painful Wrist)

The forearm consists of two bones, the radius, and the ulna. The radius is the larger of the two forearm bones, and the region closest to the wrist is called the distal end. A fracture or break in the distal end of the radius bone is known as a distal radius fracture.

Finger Dislocation

Finger Dislocation

Finger dislocation is a condition in which the bone of your finger has moved away from its normal position.

Finger Sprain

Finger Sprain

Injuries that involve tearing or stretching of the ligaments of your fingers are termed as sprains. Sprains in the fingers are most often caused from a fall when you extend your arms to reduce the impact of the fall, or from overuse or repetitive activity of the thumb such as with texting.

Ganglion Cyst

Ganglion Cyst

Ganglion cysts are swellings that most commonly develop along the tendons or joints of wrists or hands. They can be found either at the top of the wrist, palm side of the wrist, end joint of a finger or at the base of a finger.

Mallet Finger

Mallet Finger

The finger joint is a hinge-joint that allows bending and straightening of the fingers. Each finger is composed of 3 phalanges joined by 2 interphalangeal joints (IP joints).

Malunion of a Fracture

Malunion of a Fracture

Malunion of a fracture is a condition where the fractured ends of a bone heal in a misaligned position resulting in bone deformity. Malunions may occur in any bone fractures in the body often due to trauma.

Scaphoid Fracture

Scaphoid Fracture

The scaphoid bone is a small, boat-shaped bone in the wrist, which, along with 7 other bones, forms the wrist joint. It is present on the thumb side of the wrist and is at high risk for fractures. A scaphoid fracture is usually seen in young men aged 20 to 30 years. They can occur at two places: near the thumb or near the forearm.

Scapholunate Advanced Collapse (SLAC) Wrist

Scapholunate Advanced Collapse (SLAC) Wrist

Idiopathic avascular necrosis of the scaphoid (Preiser disease)

Thumb Fracture

Thumb Fracture

A break or a crack in the bones of the thumb is known as a thumb fracture. Fractures may occur anywhere on the thumb, but a fracture at the base of the thumb, near the wrist, is considered the most serious.

Trigger Finger

Trigger Finger

The ability to bend the fingers is governed by supportive tendons that connect muscles to the bones of the fingers. The tendons run along the length of the bone and are kept in place at intervals by tunnels of ligaments called pulleys.

Triscaphoid Joint Arthritis

Triscaphoid Joint Arthritis

Arthritis is an inflammatory condition of one or more joints in your body. Triscaphoid joint arthritis is the localized pain and inflammation of the shared joint between the 3 carpal bones of your wrist.

Ulnar Nerve Compression in Guyon's Canal

Ulnar Nerve Compression in Guyon's Canal

Ulnar nerve compression in Guyon’s canal is a condition characterized by pain, numbness, weakness, and tingling sensation in the hand. The condition occurs when the ulnar nerve, the nerve that travels across the elbow from the shoulder to the hand, is compressed as it goes from the wrist into the hand through a space known as Guyon’s canal.

Wrist Injuries

Wrist Injuries

The wrist is a commonly injured joint in the body. Problems include sprains and strains as well as fractures that can occur with lifting and carrying heavy objects, while operating machinery, bracing against a fall, or from sports-related injuries.

Wrist Pain

Wrist Pain

Wrist pain is defined as any ache or discomfort in the wrist. The wrist is comprised of two bones in the forearm, the radius and ulna, and eight tiny carpal bones in the palm.

Carpal Tunnel Release Surgery

Carpal Tunnel Release Surgery

Carpal tunnel syndrome is a common, painful, progressive condition that is caused by the compression of the median nerve at the wrist area.

Finger Joint Fusion

Finger Joint Fusion

The hands are made up of 27 bones, which are grouped into carpals, metacarpals and phalanges. Each bone is separated by the articular cartilage, which helps provide smooth gliding movements of the fingers.

Hand Fracture Surgery

Hand Fracture Surgery

The hand is one of the most flexible and useful parts of our body. Because of overuse in various activities, the hands are more prone to injuries, such as sprains and strains, fractures and dislocations, lacerations and amputations while operating machinery, bracing against a fall and sports-related injuries.

Lrti For Thumb Cmc Arthritis

Lrti For Thumb Cmc Arthritis

The joint located at the base of the thumb is known as the carpometacarpal (CMC) joint. The thumb CMC joint is where the metacarpal bone of the thumb connects to the trapezium (carpal) bone of the wrist. The CMC is the joint most affected in thumb arthritis.

Nerve Decompression Of The Upper Extremities

Nerve Decompression Of The Upper Extremities

Nerve decompression of the upper extremities, also called peripheral nerve decompression, is a minimally invasive surgical procedure employed to relieve pressure on an entrapped or pinched nerve (neuroma) for the treatment of conditions such as carpal tunnel syndrome and cubital tunnel syndrome, the two most common nerve compression syndromes.

ORIF of Distal Radius Fracture

ORIF of Distal Radius Fracture

The forearm consists of two bones, the radius and ulna. The radius is the larger of the two forearm bones, and the region towards the wrist is called the distal end. A fracture or break in the distal end of the radius bone is known as a distal radius fracture.

ORIF of the Forearm Fractures

ORIF of the Forearm Fractures

The forearm is made up of two bones, the radius and ulna. A break in both or either of the bones is known as forearm fracture. Forearm fractures can occur near the wrist, near the elbow, or in the middle of the forearm. A forearm fracture affects the ability to rotate your arm, as well as bend and straighten the wrist and elbow.

Surgery For Thumb And Digit Arthritis

Surgery For Thumb And Digit Arthritis

Arthritis is an inflammatory condition of the joints. There are several types of arthritis; the most common type is osteoarthritis or wear-and-tear arthritis that affects the joint at the base of the thumb. Thumb arthritis is more common in women than men, and usually occurs after the age of 40 years.

Total Wrist Arthrodesis

Total Wrist Arthrodesis

The wrist joint is one of the most complex joints in the human body. Numerous joints and bones contribute to the strength and stability of the wrist. The wrist is made up of eight separate small bones called carpal bones.

Wrist Arthroscopy

Wrist Arthroscopy

Your wrist is a complex joint made up of eight small bones called carpal bones. These bones are supported by connecting ligaments. Various conditions can affect your wrist joint such as carpal tunnel syndrome, osteoarthritis and others.

Wrist Fracture Fixation

Wrist Fracture Fixation

Wrist fractures are breaks in any of the bones that form your wrist joint.

Wrist Open Reduction and Internal Fixation

Wrist Open Reduction and Internal Fixation

Open reduction and internal fixation of the wrist is a surgical technique employed for the treatment of severe wrist fractures to restore normal anatomy and improve range of motion and function.