Valgus Extension Overload
Valgus extension overload is a syndrome of elbow symptoms and pathology common to throwing athletes. The condition is caused by a repetitive valgus force and medial laxity of the elbow leading to excessive shear forces and compression of the articulation between the posteromedial olecranon and the olecranon fossa (Fig. 32.1). Consequently, osteophytic change can occur at the posteromedial tip of the olecranon or in the olecranon fossa in compensation for elbow instability. The presence of osteophytes at this location is the most common diagnosis in professional baseball players undergoing open or arthroscopic elbow surgery. Surgical treatment of valgus extension overload is effective as advances in elbow arthroscopy instrumentation and technique continue to evolve. The excessive forces to which the elbow is exposed during the throwing motion comprise 64 Nm of valgus stress during the late cocking and acceleration phases, 300 N of medial shear force as the elbow extends at over 2300°/s during the acceleration phase and 900 N of lateral compressive force during the deceleration phase .
KeywordsElbow arthroscopy Osteophytes Posteromedial impingement Valgus extension overload
Declaration of Conflict of Interest: T. David Luo, M.D.—No conflicts of interest or financial ties to disclose.
Michael T. Freehill, M.D. AAOS, board or committee member, American Orthopedic Society for Sports Medicine; board or committee member, Arthroscopy Association of North America; board or committee member, International Society of Arthroscopy, Knee Surgery, and Orthopedic Sports Medicine; board or committee member, Integra consultant, American Shoulder Elbow Surgery. Board or committee member, Regeneration Technologies, Inc.; research support, Smith & Nephew; paid consultant, research support.
Hilgersom NFJ and Bexkens R have no conflicts of interest or financial ties to disclose. Eygendaal D is a consultant for Lima Elbow System and as a speaker for the AO foundation. van den Bekerom MPJ has received an enabling grant from Smith and Nephew for research in rotator cuff surgery and research funding from Tornier.