The Orthopaedic Management of Arthrogryposis Multiplex Congenita

Abstract

Arthrogryposis multiplex congenita (AMC) describes a baby born with multiple joint contractures that results from fetal akinesia with at least 400 different causes. The most common forms of AMC are amyoplasia (classic arthrogryposis) and the distal arthrogryposes. Over the past two decades, the orthopaedic treatment of children with AMC has evolved with a better appreciation of the natural history. Most adults with arthrogryposis are ambulatory, but less than half are fully independent in self-care and most are limited by upper extremity dysfunction. Chronic and episodic pain in adulthood—particularly of the foot and back—is frequent, limiting both ambulation and standing. To improve upon the natural history, upper extremity treatments have advanced to improve elbow motion and wrist and thumb positioning. Attempts to improve the ambulatory ability and decrease future pain include correction of hip and knee contractures and emphasizing casting treatments of foot deformities. Pediatric patients with arthrogryposis require a careful evaluation, with both a physical examination and an assessment of needs to direct their treatment. Further outcomes studies are needed to continue to refine procedures and define the appropriate candidates. Key Concepts: • Arthrogryposis multiplex congenita (AMC) is a term that describes a baby born with multiple joint contractures. Amyoplasia is the most common form of AMC, accounting for one-third to one-half of all cases, with the distal arthrogryposes as the second largest AMC type. • There are more than 400 different underlying conditions all of which result in fetal akinesia, causing the joint contractures. • Most adults with arthrogryposis are ambulatory but only a minority are fully independent in their daily activities, usually related to limited upper extremity function. • Care of the upper extremity is directed to correct elbow extension contractures and shoulder internal rotation contractures and are best performed under 2 years of age. • The regular use of Ponseti casting for clubfeet, along with the development of techniques for treating hip and knee contractures has improved lower extremity function.