Bilateral Atypical Femoral Fractures after Bisphosphonate Treatment for Osteoporosis: A Literature Review

Abstract

Introduction: This literature review aimed to investigate the incidence, anatomical concerns, etiology, symptoms, diagnostic tools, management, and prognosis of bisphosphonate (BP)—associated bilateral atypical femoral fractures (AFFs). Methods: The PubMed, Cochrane Library, Web of Sciences, and CINAHL databases were searched up to 20 March 2022. All cases of bilateral AFFs were included, excluding those without any bisphosphonate treatment information and those in which the femoral fracture did not precisely fit into the diagnostic criteria for AFF. Results: We identified 43 patients with bilateral AFFs associated with BP use and conducted a comprehensive analysis. Among 43 patients, 29 (67%) had prodromal symptoms. Regarding the simultaneity of fracture, 21 cases (49%) occurred simultaneously, and 22 cases (51%) occurred sequentially. Alendronate was the most commonly used BP treatment (59%). Regardless of the medication type, BP intake duration was more than 5 years in 77%. The initial diagnosis was performed using X-rays in all cases. A total of 53% of patients had complete fractures, and all patients underwent surgical treatment. Among the remaining patients with incomplete fractures, 18% and 29% received surgical and medical treatments, respectively. After BP discontinuation, teriparatide was most commonly used (63%). Conclusions: The careful evaluation of relevant imaging findings in patients with thigh/groin pain allows the identification of early incomplete fractures and timely management. Since the rate of contralateral side fractures is also high, imaging studies should be performed on the asymptomatic contralateral side.

Impending Atypical Femoral Fracture on the Contralateral Side Progressed to a Complete Fracture Early after Surgery for an Atypical Femoral Fracture: A Case Report

“…Radiography and CT are useful for diagnosing AFFs. According to a review of AFFs in a report by a task force of the American Society for Bone and Mineral Research (ASBMR), 100 out of 100,000 patients treated with BPs for more than 3 years develop AFFs every year [ 5 ], with the occasional occurrence of a bilateral AFFs; however, simultaneous occurrence of bilateral complete fracture is rare [ 1 - 4 ]. BPs negatively affect collagen maturation in the bone, reduce turnover, result in accumulated damage from load stress, and reduce strength [ 6 , 7 ].…”

“…Long-term bisphosphonate (BP) administration may cause an atypical femoral fracture (AFF) that is occasionally bilateral [ 1 - 4 ]. Imaging tests of both legs are necessary to diagnose atypical incomplete fractures [ 5 ].…”