Clinical Anatomy of the Hand and Fingers

Overview

• Focus on the clinical anatomy of the hand, especially the wrist joint.
• Examining from a palmar view (palm side) of the right hand.

Surface Anatomy

• Scaphoid Bone: Tuberosity can be felt.
• Pisiform Bone: Can be felt along with the hook of the hamate.

Forearm Bones

• Ulna: Medially located.
• Radius: Lateral position; can feel the radial artery.

Wrist Bones (Carpal Bones)

• Eight carpal bones, organized in two rows:
  • Proximal Row: Scaphoid, Lunate, Triquetrum, Pisiform.
  • Distal Row: Trapezium, Trapezoid, Capitate, Hamate.
• Mnemonic: "So Long To Pinky, Here Comes The Thumb"

Metacarpals and Phalanges

• Metacarpals: Bones of the hand.
• Phalanges: Distal, middle, and proximal phalanges (fingers), except the thumb which has no middle phalanx.

Flexor Retinaculum

• Important structure running across the hamate and trapezium.
• Structures running deep to flexor retinaculum include:
  • Median nerve
  • Tendons of flexor digitorum superficialis
  • Tendons of flexor digitorum profundus
  • Tendon of flexor pollicis longus
• Structures running superficial to flexor retinaculum:
  • Tendon of palmaris longus
  • Ulnar artery and nerve
  • Palmar cutaneous branches of median and ulnar nerves

Clinical Relevance

• Carpal Tunnel Syndrome: Compression of median nerve under flexor retinaculum causing numbness, paresthesia, pain.
• Dupuytren's Contracture: Thickening and contracture of palmar aponeurosis causing finger flexion deformities.

Finger Anatomy

• Focus on index, middle, ring, and pinky (not thumb).
• Phalanges: Distal, middle, proximal.
• Tendons:
  • Flexor digitorum superficialis: Attaches to middle phalanx, flexes proximal interphalangeal joint.
  • Flexor digitorum profundus: Attaches to distal phalanx, flexes distal interphalangeal joint.

Trigger Finger

• Condition where thickening of flexor tendon prevents movement within fibrous sheath.
• Typically occurs between metacarpal and proximal phalanx.
• Causes restricted flexion of the finger.