A long bone is a bone that has a shaft and 2 ends and is longer
than it is wide. Long bones have a thick outside layer of compact
bone and an inner medullary cavity containing bone marrow. The ends
of a long bone contain spongy bone and an epiphyseal line. The
epiphyseal line is a remnant of an area that contained hyaline
cartilage that grew during childhood to lengthen the bone. All of
the bones in the arms and legs, except the patella, and bones of
the wrist, and ankle, are long bones.
Review Date: 08/10/2009
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of
General Medicine, Department of Medicine, University of Washington
School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical
Director, A.D.A.M., Inc.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)
