Swan neck deformity

Background

• Delayed complication of chronic untreated mallet finger
• Seen also in rheumatoid arthritis, trauma
• Lateral bands displace proximally and dorsally = increased extension of PIP.
• FDP unopposed

Clinical Features

• PIP extension with DIP flexion

Differential Diagnosis

• Joint volar subluxation
• FDS laceration
• Intrinsic contracture

Hand and finger injuries

• Radiograph positive
  • Hand and finger fractures
  • Hand and finger dislocations
  • Triquetrolunate ligament instability
• Radiograph negative
  • Dupeytren contracture
  • Boutonniere deformity
  • Hand and finger tendon injuries
  • Ganglion cyst
  • De Quervain tenosynovitis
  • Intersection syndrome
  • Drummer's wrist
  • Extensor digitorum tenosynovitis
  • Vaughn Jackson syndrome
  • Snapping Extensor Carpi Ulnaris
  • Compressive neuropathy, "bracelet syndrome"
  • Scaphoid fracture
  • Osteoarthritis
  • Infiltrative tenosynovitis
  • Gout
  • Rheumatoid arthritis
  • Trigger finger
  • Mallet finger
    • Swan neck deformity
  • Jersey finger
  • Jammed finger
  • Subungual hematoma
  • Fingertip laceration
  • Metacarpophalangeal (MCP) ulnar ligament rupture (Gamekeeper's thumb)
  • Nail avulsion
  • High-pressure injection injury

Evaluation

• Clinical diagnosis, XR to rule out avulsion fracture

Management

• Extension Block Splint

Disposition

• Orthopedic referral

See Also

• Hand and finger diagnoses
• Hand Tendon Injuries

References

Authors

Hemang Acharya, Ross Donaldson, Neil Young