Potential contribution of pedicle screw design to loosening rate in patients with degenerative diseases of the lumbar spine: An observational study.

Background: The majority of published data report the results of biomechanical tests of various design pedicle screw performance. The clinical relevance and relative contribution of screw design to instrumentation stability have been insufficiently studied.

Aim: To estimate the contribution of screw design to rate of pedicle screw loosening in patients with degenerative diseases of the lumbar spine.