Authors: Jens Ivar Brox; Roger Sørensen; Astrid Friis; Øystein Nygaard; Aage Indahl; Anne Keller; Tor Ingebrigtsen; Hege R Eriksen; Inger Holm; Anne Kathrine Koller; Rolf Riise; Olav Reikerås Journal: Spine (Phila Pa 1976) Date: 2003-09-01 Impact factor: 3.468