Surgery for ossification of the ligamentum flavum

Abstract

Introduction Ossification of the ligamentum fl avum (OLF) is one of the most common causes of compression myelopathy in degenerative processes of the thoracic spine [1]. When OLF is the sole compressive factor in a patient with thoracic myelopathy, posterior surgery is indicated because the myelopathy usually is not alleviated by conservative treatments but, rather, continues to deteriorate. OLF varies in range and shape depending on the patient. Although it has been fairly diffi cult to ascertain OLF correctly on conventional plain radiographs, nowadays OLF can be well depicted by computed tomography (CT). Posterior surgery for OLF consists basically of two procedures: laminectomy and fenestration. The procedure should be as minimally invasive as possible, but at the same time it is necessary to be safe enough to prevent surgical complications, which are not infrequent with thoracic spine surgery [2]. We describe in this chapter (1) the classifi cation of OLF using CT fi ndings, which is essential for choosing the appropriate procedure; (2) the surgical techniques for each procedure; and (3) the surgical results. © 2006 Springer.