Osteoporosis refers to a systemic bone disease characterized by an imbalance in the mineral content within bone structures, such as calcium and phosphorus, as well as the bone matrix, such as collagen, leading to decreased bone hardness and damage to the bone's microstructure. This structural change results in increased brittleness, thereby raising the risk of fractures. It is primarily caused by a disruption in the normal proportional relationship between inorganic salts and the bone matrix, generally due to the loss of inorganic salts like calcium and phosphorus.