Atypical incomplete femoral neck fracture in patients taking long-term bisphosphonate: Case report, a report of 2 cases

• Published in: Medicine (Baltimore) 2019-03, Vol.98 (9), p.e14701-e14701
• Main Authors: Suh, You-Sung, Jang, Byung-Woong, Nho, Jae-Hwi, Won, Sung-Hun, Lee, Won-Seok
• Format: Article
• Language: English
• Subjects: Aged; Clinical Case Report; Diphosphonates - adverse effects; Diphosphonates - therapeutic use; Female; Femoral Neck Fractures - chemically induced; Femoral Neck Fractures - surgery; Fracture Fixation, Internal; Fracture Healing - physiology; Humans; Osteoporosis - drug therapy
• ISSN: 0025-7974; 1536-5964
• DOI: 10.1097/MD.0000000000014701

We present 2 cases of lateral incomplete impending fracture of the femoral neck without trauma in elderly patients taking long-term bisphosphonate (BP) treatment, and we defined it as atypical femoral neck fracture (AFNF). To the best of our knowledge, this is the first report on the follow-up results of AFNF. Patients in both cases had been taking BP drugs for a long time with osteoporosis. The duration of BP treatment was 6 years, and there was no history of repeated stresses. All fractures were linear at the lateral aspect of the mid portion of the femoral neck, and the BMD of the femoral neck was -0.9, and -1.8, respectively. Internal fixation was performed in both cases (73 years, 68 years) using cannulated screws. In both patients who underwent screw fixation, the fracture line started to extend distally at 4 weeks and 2 weeks following surgery. In the 3-month follow-up image, the length of the fracture increased by 20.1 mm and 9.9 mm, respectively. There was a problem with active rehabilitation, and the possibility of revision was also found to be a burden in terms of mortality and cost in older patients. In the case of AFNF, guidelines for treatment should be set in consideration of the decreased bone healing, even when the fracture pattern is simple. Arthroplasty based on a wider indication may be worth considering.