Hand exam

Background

Wrist and hand deeper palmar dissection

Distal interphalangeal dislocation (DIP), proximal interphalangeal dislocation (PIP), and metacarpophalangeal dislocation (MCP) joints of the finger shown.

Volar/anterior finger anatomy.

Lateral finger anatomy.

• Must exam tendon injuries in their entirety through full range of motion
  • Injuries with digits in flexion may cause retraction of cut end of tendon when examined in neutral position
• All exams should include a thorough history of events

Hand Anatomy

• Volar = anterior = palmar
• Dorsal = posterior

Nailtip Anatomy

A. Nail plate; B. lunula; C. root; D. sinus; E. matrix; F. nail bed; G. hyponychium; H. free margin.

• The perionychium includes the nail bed and the paronychium.
• The paronychium is the lateral nail fold (soft tissue lateral to the nail bed).
• The hyponychium is the palmar surface skin distal to the nail.
• The lunula is that white semi-moon shaped proximal portion of the nail.
• The sterile matrix is deep to the nail, adheres to it and is distal to the lunule.
• The germinal portion is proximal to the matrix and is responsible for nail growth.

Exam

Inspection

• General appearance
  • Wounds, atrophy, discoloration, swelling, masses, nail changes
• Palpate for: Crepitus, deformity, joint tenderness, rotation deformity, snuffbox tenderness

Motor

• Bilateral grip strength
• Have patient make a clenched fist
  • Observe orientation and rotation of middle and distal phalanxes
  • Assess for scissoring (overlapping of digits)
  • All phalanges should be oriented parallel to each other with nails in same plane
• Have patient draw fingertips together so tip of thumb touches tips of the other 4 digits
  • Gross estimation of intact median, ulnar, and radial nerve motor function
• Pincer function test
  • Weakness suggests median nerve or ulnar collateral ligament disruption

Tendons

• Must test with resistance
• Pain along course of tendon during resistance testing suggests partial rupture
• Flexor digitorum profundus (FDP)
  • Flex DIP against resistance while MCP and PIP joints are held in extension
• Flexor digitorum superficialis (FDS)
  • Flex PIP against resistance while remaining fingers are held in extension, especially the DIPs of the remaining fingers
• Extensor tendons
  • Hand flat on surface and lift fingers individually

Circulation

• Assess via cap refill and radial pulse
• Allen test

Nerve Testing

• Median
  • Controls thumb opposition and 1st and 2nd lumbricals
  • Recurrent motor branch: Have patient touch tip of thumb to tip of little finger so the nails are touching
  • Anterior interosseous branch: Have patient make an OK-sign. Thumb IP and index DIP should be flexed, making a circle shape rather than a teardrop shape
  • Sensation to distal 2nd digit

• Ulnar
  • Controls thumb adduction and 3 and 4th lumbricals
  • Have patient spread the fingers apart against resistance
  • Interpose a tongue depressor between thumb and index finger and try to pull radially
  • Sensation to distal 5th digit

• Radial
  • Controls thumb and wrist extension
  • Have patient make "thumbs up". Alternatively, have patient perform wrist extension against resistance (tests for wrist drop)
  • Sensation over the dorsal web space between the 1st and 2nd digits

See Also

• Hand and finger diagnoses