Image Review

From the EMDaily Archives: What’s the Diagnosis? By Dr. Jacob Martin

A 40 year old male presents for right wrist pain. Onset was just before arrival when he was lifting at work, “felt a pop”, and had a sudden onset of pain. Exam reveals swelling and tenderness of the right wrist. Neurovascular exam is normal. A right wrist x-ray is performed and shown below. What’s the diagnosis?

Answer: Scapholunate Dissociation

  • Background
    • Scapholunate ligament is most commonly injured ligament in the wrist
    • SLD is part of a spectrum of traumatic carpal bone instabilities
  • Etiology
    • Most commonly occurs with FOOSH injury causing forceful wrist extension, rupturing the scapholunate interosseous ligament
    • Also associated with spastic paresis, rheumatoid arthritis, and congenital ligament laxity
  • Presentation
    • Wrist swelling and point tenderness over dorsal aspect of wrist
    • Pain with wrist extension, radial deviation, and “clicking” sensation with movement
  • Diagnosis
    • Obtain AP and lateral views (+/- grip compression view/wrist in ulnar deviation)
    • Radiographic signs:
      • Widening of the scapholunate joint space > 3mm (“Terry Thomas sign”)
      • Cortical ring sign – loss of ligamentous support results in rotary subluxation and palmar tilt of the scaphoid on AP radiograph 
    • MRI provides definitive diagnosis, rarely done in ED 
  • ED Management
    • Pain management
    • Radial gutter splint
    • Urgent referral to orthopedics/hand specialist 
  • Pearls and Pitfalls
    • Prompt recognition crucial
    • Delayed diagnosis is associated with chronic pain, joint instability, inflammatory arthritis, long-term degenerative changes


Casey PD, Youngberg R.Scapholunate dissociation: a practical approach for the emergency physician.J EmergMed. 1993;11(6):701-707. doi:10.1016/0736-4679(93)90629-l

Long B, Koyfman A. Wrist Injuries. In: Tintinalli JE, Ma O, Yealy DM, Meckler GD, StapczynskiJ, Cline DM, ThomasSH. eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 9e. McGraw-Hill; Accessed September 29,2020.

Ramponi D, McSwigan T. ScapholunateDissociation.Adv Emerg Nurs J. 2016;38(1):10-14.doi:10.1097/TME.0000000000000094

Stevenson M, Levis JT. Image Diagnosis: Scapholunate Dissociation.Perm J. 2019;23:18-237. doi:10.7812/TPP/18-237

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