<prompt> What causes mallet finger?Extensor tendon ruptureBony avulsion of distal phalanx at the extensor tendonStrain and subsequent stretching of the extensor tendonAll the above  <response>: Mallet finger: A finger flexed at the DIP joint due to avulsion or rupture of extensor tendon at the base of the distal phalanx. Mallet finger occur due to forced flextion of the finger tip. Hyper- extension splint is the treatment for atleast 6-8 weeks. 