27 - Extensor tendon injuries

Abstract

▪A thorough understanding of the complex anatomy is crucial for successful treatment of extensor tendon injuries.▪Injuries are classified into nine anatomic zones. Treatment strategies vary considerably according to the location of the lesion, ranging from splinting to tendon grafting.▪Minimal variations in tendon length may result in considerable alteration in range of motion.▪As in flexor tendon injuries, postoperative care is an essential part of the treatment concept.▪Closed ruptures of the extensor tendon at the level of the distal interphalangeal (DIP) and proximal interphalangeal (PIP) joints are typically treated conservatively.▪Lacerations at the level of the metacarpophalangeal (MCP) joint (zone V) are not infrequently caused by human bites and are prone to infection unless thoroughly debrided.▪Ruptures of the sagittal bands may result in subluxation of the extensor tendon at the level of the MCP joint.▪The swan-neck deformity is characterized by DIP joint flexion and PIP joint hyperextension. It can be caused by an untreated mallet injury or palmar plate laxity.▪The boutonnière deformity is characterized by hyperextension of the DIP joint and PIP joint flexion. It can be caused by rupture of the central slip of the extensor tendon or palmar subluxation of the lateral bands.▪Complex injuries to the dorsum of the hand can involve skin, tendon, and bone. Adequate debridement is of paramount importance. Before reconstructing tendons, fractures must be stabilized, and stable soft tissue coverage must be provided.