Soft tissue edema

Soft tissue edema is the accumulation of fluid within the supporting tissues around the bones of the spine. The most common cause of soft tissue edema is traumatic or overuse injury. Within the spine it can occur between the bones of the spinous processes of the vertebrae (interspinous), it can occur within a muscle, or a set of muscles adjacent to the vertebrae (paraspinal), or it can occur within the subcutaneous layers of the lower back.