Corpus: Hand

The hand comprises an osseous framework, associated muscles, ligaments, tendons, blood vessels, and nerves. Anatomically, it is divided into the carpals (wrist bones), metacarpals (forming the palm and back of the hand), and phalanges (finger bones).

Beneath the palm's skin lies the palmar aponeurosis, a tendon plate connected to the skin via fibers. This structure helps prevent excessive displacement of soft tissues during firm gripping.

Skeleton of the Hand

The hand's osseous component includes the small carpal bones and the tubular metacarpals and phalanges. The bones are organized as follows:

• Proximal row of the carpus
  • Scaphoid bone
  • Lunatum bone
  • Triquetral bone
  • Pisiform bone

• Distal row of the carpus
  • Trapezium bone
  • Trapezoid bone
  • Capitate bone
  • Hamate bone

• Metacarpal bones
  • Metacarpal bones I – V

• Finger bones
  • Proximal phalanges I – V
  • Middle phalanges II – V (the thumb consists of only two phalanx bones)
  • Distal phalanges I – V

Hand Musculature

The bones, interconnected via joints, are mobilized by forearm muscles and the hand's intrinsic muscles. The hand muscles are categorized into the radial thenar (thumb), ulnar hypothenar (little finger), and palmar muscles.

Thenar Musculature

• Abductor pollicis brevis muscle
• Adductor pollicis muscle
• Flexor pollicis brevis muscle
• Opponens pollicis muscle

Hypothenar Musculature

• Abductor digiti minimi muscle
• Flexor digiti minimi brevis muscle
• Opponens digiti minimi muscle
• Palmaris brevis muscle

Palm Musculature

• Interossei palmares muscles
• Interossei dorsales muscles
• Lumbricales muscles

Blood Vessels and Nerves

Sensory innervation (joints, skin, ligaments, and tendons) and motor innervation (muscles) are provided by the median, radial, and ulnar nerves.

Blood supply is via the radial and ulnar arteries, interconnected by the superficial and deep palmar arches.

The hand's complex structure enables touching and grasping. Critical functions include flexion of fingers II-V and the opposition of the thumb, essential for gripping.

• Various diseases can significantly impair hand function, including:
• Chronic polyarthritis (rheumatism)
• Osteoarthritis of the finger joints
• Gout
• Dupuytren's contracture
• Carpal tunnel syndrome

Hand surgery, a specialized surgical field, focuses on hand reconstruction post-injuries.

• 3D-model: Dr. Claudia Krebs (Faculty Lead) University of British Columbia