This books provides EBP physiotherapy research protocols for the management of post-opertive LBP .Lumbar fusion surgery is one of the most common spinal surgery. The goal of this surgery is to provide fusion of the vertebra and thereby improving functional outcomes. The purpose of this study is to investigate the association of low back and psychological variables with function in subjects who underwent posterior lumbar interbody fusion.Low back pain (both at rest and during movement), radiating pain during movement and kinesiophobia were associated with functional outcomes.