Authors: Peter Grunert; Katherine D Hudson; Michael R Macielak; Eric Aronowitz; Brandon H Borde; Marjan Alimi; Innocent Njoku; Douglas Ballon; Apostolos John Tsiouris; Lawrence J Bonassar; Roger Härtl Journal: Spine (Phila Pa 1976) Date: 2014-03-15 Impact factor: 3.468