Hand exam
Background
- 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 = dorsal
- Dorsal = posterior = palmar
Nailtip Anatomy
- The perinychium includes the nail, the nailbed, and the surrounding tissue.
- The paronychia is the lateral nail folds
- 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