Evaluation of the postoperative spine: spinal instrumentation and fusion

Spinal instrumentation is used in a variety of clinical settings ranging from degenerative spine disease to tumors and infection. The primary goal is to provide internal fixation in a region of the spine to facilitate development of an osseous fusion. Hardware is often used to improve alignment and reduce deformities. It is selected based on the anatomic region, ease of implantation and postoperative care, and physician preference. This article will review the basic components of hardware used in the cervical, thoracic, and lumbar spine for anterior and/or posterior fusion. It will not review specific hardware in detail but will discuss general concepts applicable to the various types and strengths and weaknesses of the components. Evaluation of fusion mass will be considered, including some of the current controversies and the current accepted practices.