It is estimated that one in ten people will have a kidney stone at some time in their lives. The prevalence of kidney stones in the United States increased from 3.8% in the late 1970s to 8.8% in the late 2000s. This increase was seen in both men and women, and both whites and blacks.The lifetime risk of kidney stones is about 19% in men and 9% in women. In men, the first episode is most likely to occur after age 30, but it can occur earlier.t is estimated that one in ten people will have a kidney stone at some time in their lives. The prevalence of kidney stones in the United States increased from 3.8% in the late 1970s to 8.8% in the late 2000s. This increase was seen in both men and women, and both whites and blacks.
Compact bone is found wrapped around the cancellous bone to protect it and is made up of osteons. These osteons are cells composed of delicate layers of lammelae which protect the nerves and blood of the inner core compact bone. On death osteons transform into lammelae and produces barrier between osteon cells located inside the compact bone matrix. Due to this the strength and density of compact bones builds up.
The basic unit of Compact Bone is an  osteon , which is also known as a  Haversian System . Each Haversian System (unit) has a cylindrical structure that consists of four parts: 1  A central tube called a Haversian Canal, which contains blood vessels and nerves.2  The Haversian Canal is surrounded by alternate layers of:.2 The Structure of Spongy Bone Spongy Bone does not include osteons (the basic unit/s of Compact Bone-see above). Instead, spongy bone consists of an irregular lattice of thin columns of bone called trabeculae (literally little beams), which contain lamellae, osteocytes, lacunae and canaliculi.