title: A classification system for anomalies of the extensor pollicis longus.
abstract: BACKGROUND
  Variations of the long extensor tendon to the thumb are very rare.
  
  
  METHODS
  We present three cases in which there was a supernumerary long extensor tendon to the thumb. In all three cases, the supernumerary tendon emerged from the fourth dorsal compartment and had a parallel course to the extensor pollicis longus.
  
  
  RESULTS
  Details of the anomalies are described along with a meta-analysis of relevant literature. A classification system of these anomalies is also proposed.
authors: Tolga
authors: T
authors: Türker
authors: Gregory A
authors: GA
authors: Robertson
authors: Sunil M
authors: SM
authors: Thirkannad