EFFECT OF SEVERITY OF ROD CONTOUR ON POSTERIOR ROD FAILURE IN SETTING OF LUMBAR PEDICLE SUBTRACTION OSTEOTOMY (PSO): A BIOMECHANICAL STUDY

摘要

Pedicle subtraction osteotomy (PSO) is a powerful technique to correct flat back deformity in the lumbar spine. Because corrections as great as 30-40 degrees can be achieved with this technique, contouring of the fusion rods can be quite extreme in PSO constructs. Rod failure (Figure 1) during the late post-operative period (<1 year) has been reported clinically and is commonly associated with pseudoarthrosis. In fact, instrumentation failure following PSO occurs frequently enough that several studies have reported and investigated revision strategies.