Arthroscopic Evaluation of Elbow Instability: An Alternative Technique

Abstract

The stability of the elbow joint depends on the bony, ligamentous, and musculoskeletal structures of the elbow. Arthroscopic instability tests are an add-on to patient’s history, clinical examination, and standard imaging studies for diagnosing both mild and complex forms of instability. Arthroscopic examination is therefore an option in clinically and radiologically suspected cases of elbow instability. With the camera in the proximal posterolateral portal, the humeroulnar compartment is expanded from medial to lateral by inserting a switching stick into the joint to probe the stability of the medial (MCL) and lateral collateral ligaments (LCL). After the arthroscope has been moved further distally, the annular ligament, LCL, and MCL are tested by inserting the switching stick between radius and ulna, humerus and radius, and humerus and ulna, respectively. PLRI is determined by testing for a separation of ulna and humerus during extension of the humeroulnar and proximal radioulnar joint while hyper-supinating the forearm. In severe PLRI, or combined multidirectional instability, a positive “elbow drive-through sign” can be demonstrated. By switching to an anterior portal, medial and lateral stability can be examined under valgus and varus stress. After examination, the final repair or reconstruction procedure can be performed if indicated.