Insufficiency Fracture of Ipsilateral Femur Neck in Patient Treated with Long Term Bisphosphonate Treatment - A Case Report -
A 78-year old female patient had a history of lumbar compression fracture 6 years ago and was taking 91.37 mg of bisphosphonate-type sodium alendronate (alendronic acid 70 mg) every week without taking other medication. She had not been exposed to excessive bearing except the regular walking as a housewife. However, she visited our hospital due to gradually intensifying pain in the right inguinal area from three days before the admission. Before the manifestation of pain, she was not restricted in her daily activity and the pain only appeared during body weight loading. According to the physical findings, no specific findings were observed other than pain in the right inguinal area. The finding of stiffening was detected around partial fracture and the fractured area of the upper end of the femur in her radiograph (). T-score was -2.1 in the femoral region according to dual-energy X-ray absorptiometry (DXA). In addition, she exhibited the normal findings of a 9.0 (reference range: 8.4-10.5) mg/dL of serum calcium, a 4.0 (reference range: 2.5-4.5) mg/dL of phosphatate, a 39 (reference range: 10-57) pg/mL of parathyroid hormone, and 72 (reference range: 30-120) IU/L of alkaline phosphatase along with a decrease at a 7.01 (reference range: 11-40) ng/mL of osteocalcin. In addition, C-telopeptide bone resorption marker was measured at 0.33 (reference range: 0.01-1.00) ng/mL of a normal finding. Based on the past medical history and other clinical findings, the patient was diagnosed as insufficiency fracture in the femoral neck which was thought to be resulted from the long-term use of bisphosphonate. Thus, multiple pin fixation was implemented (). The patient was postoperatively prohibited to take bisphosphonate and prescribed from taking calcium-vitamin D (calcium 600 mg + Vitamin D 400 IU) complex every day. She was allowed for partial weight bearing using a walking frame until the second postoperative month and for the entire weight bearing after the second postoperative month. In the 4th postoperative month of follow-up period, the findings of bone reduction and pain loss were confirmed. Up to this time, physical examinations were regularly performed, including radiography and the presence of pain ().