Inflammation of the joints is referred to as arthritis. The inflammation arises when the smooth covering (cartilage) at the end surfaces of the bones wears away. In some cases, the inflammation is caused when the lining of the joint becomes inflamed as part of an underlying systemic disease.
Transient osteoporosis of the hip is a rare condition that causes bone loss temporarily in the upper part of the thighbone (femur). It is mostly found in young or middle-aged men between the ages of 30 and 60, and women in their later stages of pregnancy or early postpartum period (following childbirth).