 The knee insufficiency fracture usually occurs in older individuals and those with knee osteoarthritis. Currently no literature study even suggests the hypothesis that this type of fracture may be a fragility fracture. A possible explanation for this information gap could be the fact that, until a few years ago, this entity was believed to be a osteonecrosis of the knee. Only recently it is becoming clear that the cause of pain and marrow bone edema that occur subtly in older individuals is, in fact, a insufficiency fracture. This study therefore aims to evaluate whether a relation between the knee insufficiency fracture and osteoporosis. Moreover, it is expected to find out if this fracture may be defined as a fragility fracture, electing the individuals affected by it to a prophylaxis for the occurrence of new osteoporotic fracture. 