Posterolateral rotatory instability of the elbow

Posterolateral rotatory instability (PLRI) of the elbow is the most common chronic instability pattern identified. It is the resultant ulno-humeral instability secondary to compromised lateral ligament complex. The characteristic injury is the avulsion of the lateral ulnar collateral ligament (LUCL) from its humeral attachment. Acute PLRI can present following simple or complex elbow dislocations. Chronic PLRI mostly follows trauma but also can be the result of iatrogenic injury.