Microarchitectural deterioration of boneThis classic image is seen a lot and taken for granted but there is a lot we can learn by looking carefully at it. This is a low-power electron microscopic image of a core biopsy probably taken from a vertebral body of probably a postmenopausal white woman with osteoporosis using a hand instrument. It shows several key features of osteoporosis the first being “porosis” or holes in the bone. The big room-like spaces seen in the middle of the image are not normally there. These areas are caused by excessive bone absorption by osteoclasts during remodeling. This happened over hundreds of remodeling cycles not all of a sudden. The yellow arrows indicate another feature signifying bone deterioration. They point out a perforated trabecular strut. There are several other examples of this seen in the picture. Again this is caused by exuberant bone remodeling by osteoclasts that penetrate a support strut during bone removal that cannot be restored by the corresponding period of bone formation by the osteoblasts. These perforated struts add bone density but not strength to the bone.