TERMINOLOGY (SYNONYMS)

INTRODUCTION

The term Schmorl’s node refers to a small protrusion of intervertebral disc material through a defect in the vertebral endplate. Each vertebral body has an endplate on the top and the bottom. Each endplate surface is covered by a layer of cartilage overlying bone. A Schmorl’s Node can develop through a defect on the superior and/or the inferior endplate. Schmorl’s Nodes usually develop at a weakened area of bone, usually a site where small blood vessels penetrate the cartilage.

Schmorl’s Nodes have many different causes and predisposing factors. Any condition which increases susceptibility for disc material to herniate through an area of weakened area of bone and cartilage can result in a Schmorl’s Node.

PREVALENCE

Schmorl’s nodes are very common. They occur more often in high weight bearing areas of the spine such as the lumbar spine (low back) and the lower thoracic region (mid back). They are often detected as incidental findings during spinal imaging studies.  Schmorl’s nodes can be identified in up to 75% of all normal spines. Each vertebrae of the spine has an endplate on the bottom and the top. Schmorl’s nodes occur more often on the inferior endplate.