Dr. M. S. Alam, MD, MBBS, CCFP, FCFP, Clinical Lecturer, Cumming School of Medicine, Calgary, University of Calgary, Family Medicine Department, Calgary, AB.

Abstract
Insufficiency Fractures (I.F) are non-traumatic fractures that occur in abnormal bone (low density bone). Usually occurs in elderly post-menopausal women and is non-traumatic. X-rays are unremarkable and MRI showed extensive bone marrow oedema and subchondral fracture.
Ms. Shirley Cooke, a 61 year old with a background of low bone mass, breast cancer, Diabetes Melitis type 2, HTN, splenic artery thrombosis came in with a dull pain on her left knee and occasionally some sharp element, with unremarkable examination on knees.
Recently, she was diagnosed with left ankle avulsion fracture of lateral maleolus and is wearing an ankle boot for healing.
It is important to make the correct diagnosis in order to avoid complications."
Key Words: Insufficiency Fracture (I.F), low bone mass, management.

An insufficiency fracture is a subtype of stress fracture, which occurs in abnormally weakened bone. Stress fractures can be classified as: a) fatigue fractures, b) pathological fractures, c) stress fractures (through normal bone) and d) insufficiency fractures.

The bone subjected to an insufficiency fracture may be histologically normal but lack mass (osteoporosis) or be intrinsically weak (osteomalacia). Osteoporosis, thinning bones, is associated with advancing age and is more common in woman and small framed individuals. It is found with a calcium poor diet, amenorrhea or menopause, inflammatory diseases such as rheumatoid arthritis, prolonged inactivity, such as following a stroke, smoking and excessive alcohol use. Osteomalacia, a disease of bone formation, is most commonly caused by a Vitamin D deficiency: poor diet or too little sunlight, Celiac disease interfering with GI uptake, liver or kidney disease and some medications. Insufficiency fractures can also occur in bone affected by Paget's disease or subjected to excessive radiation therapy. Although bisphosphonates are routinely used to treat osteoporosis, atypical proximal femoral fractures have been reported.¹ Insufficiency fractures occur most often in the vertebrae, sacrum, femoral neck, proximal femur (associated with bisphosphonates), femoral condyles, proximal tibia and talus. DM