The impact of intermittent retraction on paraspinal muscle function during lumbar surgery.

Study Design: Prospective cohort study.

Objective: To study the effect of surgical retraction on paraspinal muscle function and investigate the effect of intermittent muscle retraction.

Summary Of Background Data: Paraspinal muscle retraction leads to increased intramuscular pressure with a reduction in local blood flow resulting in ischemic damage.

The impact of self-retaining retractors on the paraspinal muscles during posterior spinal surgery.

Study Design: This was a prospective pilot study examining pre-, intra- and postoperative measures.

Objectives: The aim of the study was to investigate the effect of muscle retractors on the posterior spinal muscles during posterior spinal surgery.

Summary Of Background Data: Previous studies have identified changes in the structure and function of the back extensor mechanism as a result of low back pain.