Posterolateral rotatory instability of the elbow

J Am Acad Orthop Surg. 2004 Nov-Dec;12(6):405-15. doi: 10.5435/00124635-200411000-00005.


Posterolateral rotatory instability of the elbow is a three-dimensional displacement pattern of abnormal external rotatory subluxation of the ulna coupled with valgus displacement on the humeral trochlea. This pattern causes the forearm bones to displace into external rotation and valgus during flexion of the elbow. Injury to the lateral ulnar collateral ligament allows abnormal supination of the ulna on the humerus. The radial head, being locked in the sigmoid (radial) notch of the proximal ulna by the annular ligament, subluxates posterior to the capitellum. The abnormality is usually posttraumatic and presents with locking, snapping, clicking, catching, and recurrent dislocation of the elbow. The clinical diagnosis is suspected from history and confirmed by the physical examination, which includes the posterolateral rotatory instability test. This test often is best performed under fluoroscopy or general anesthesia. Usually the instability is managed with either a repair of the ligament or an isometric reconstruction using a tendon graft.

Publication types

  • Comparative Study
  • Review

MeSH terms

  • Arthroscopy / methods
  • Biomechanical Phenomena
  • Elbow Injuries*
  • Female
  • Follow-Up Studies
  • Humans
  • Injury Severity Score
  • Joint Dislocations / diagnosis
  • Joint Dislocations / surgery*
  • Joint Instability / etiology
  • Joint Instability / prevention & control*
  • Male
  • Orthopedic Procedures / methods*
  • Pain Measurement
  • Range of Motion, Articular / physiology
  • Recovery of Function
  • Rotation
  • Treatment Outcome