1 For example, if you sell a product for $25, and it costs $20 to make, the gross profit margin is 20% ($5 divided by $25). 2  Net Profit Margin: This is often the equation used to determine an entire organizationâs profit margin.
Avascular necrosis (AVN), also called osteonecrosis, aseptic necrosis, or ischemic bone necrosis, is a condition that occurs when there is loss of blood to the bone. Because bone is living tissue that requires blood, an interruption to the blood supply causes bone to die. If not stopped, this process eventually causes the bone to collapse.
Avascular necrosis (AVN) of the femoral head is a pathologic process that results from interruption of blood supply to the bone. AVN of the hip is poorly understood, but this process is the final common pathway of traumatic or nontraumatic factors that compromise the already precarious circulation of the femoral head. Femoral head ischemia results in the death of marrow and osteocytes and usually results in the collapse of the necrotic segment. (See also the Medscape Reference article Imaging in Avascular Necrosis of the Femoral Head, as well as Hip Arthroscopy in Staging Avascular Necrosis of the Femoral Head on Medscape News.)