Association of low-energy femoral fractures with prolonged bisphosphonate use: a case control study

• Published in: Osteoporosis international Vol. 20; no. 8; pp. 1353 - 1362
• Main Authors: Lenart, B. A, Neviaser, A. S, Lyman, S, Chang, C. C, Edobor-Osula, F, Steele, B, van der Meulen, M. C. H, Lorich, D. G, Lane, J. M
• Format: Journal Article
• Language: English
• Published: London London : Springer-Verlag 01-08-2009; Springer-Verlag; Springer; Springer Nature B.V
• Subjects: Aged; Aged, 80 and over; Biological and medical sciences; Bisphosphonate; Body Mass Index; Bone Density Conservation Agents - administration & dosage; Bone Density Conservation Agents - adverse effects; Bones; Bones, joints and connective tissue. Antiinflammatory agents; Case-Control Studies; Diphosphonates - administration & dosage; Diphosphonates - adverse effects; Diseases of the osteoarticular system; Drug Administration Schedule; Drug therapy; Endocrinology; Female; Femoral Fractures - chemically induced; Femoral Fractures - diagnostic imaging; Femoral Fractures - etiology; Femoral Neck Fractures - chemically induced; Femoral Neck Fractures - etiology; Femoral shaft; Fractures; Hip fracture; Humans; Injuries of the limb. Injuries of the spine; Legs; Low energy; Medical sciences; Medicine; Medicine & Public Health; Menopause; Original Article; Orthopedics; Osteoporosis; Osteoporosis, Postmenopausal - complications; Osteoporosis, Postmenopausal - drug therapy; Osteoporosis. Osteomalacia. Paget disease; Pharmacology. Drug treatments; Radiography; Rheumatology; Risk factors; Subtrochanteric; Traumas. Diseases due to physical agents; Women; Low energy; Femoral shaft; Osteoporosis; Bisphosphonate; Hip fracture; Subtrochanteric; Femur; Antiosteoporotic; Diseases of the osteoarticular system; Rheumatology; Fracture; Case control study; Trauma; Bisphosphonates; Hip; Antiosteoclastic agent
• ISSN: 0937-941X; 1433-2965
• DOI: 10.1007/s00198-008-0805-x

Summary Recent evidence has linked long-term bisphosphonate use with insufficiency fractures of the femur in postmenopausal women. In this case-control study, we have identified a significant association between a unique fracture of the femoral shaft, a transverse fracture in an area of thickened cortices, and long-term bisphosphonate use. Further studies are warranted. Introduction Although clinical trials confirm the anti-fracture efficacy of bisphosphonates over 3-5 years, the long-term effects of bisphosphonate use on bone metabolism are unknown. Femoral insufficiency factures in patients on prolonged treatment have been reported. Methods We performed a retrospective case-control study of postmenopausal women who presented with low-energy femoral fractures from 2000 to 2007. Forty-one subtrochanteric and femoral shaft fracture cases were identified and matched by age, race, and body mass index to one intertrochanteric and femoral neck fracture each. Results Bisphosphonate use was observed in 15 of the 41 subtrochanteric/shaft cases, compared to nine of the 82 intertrochanteric/femoral neck controls (Mantel-Haenszel odds ratio (OR), 4.44 [95% confidence interval (CI) 1.77-11.35]; P = 0.002). A common X-ray pattern was identified in ten of the 15 subtrochanteric/shaft cases on a bisphosphonate. This X-ray pattern was highly associated with bisphosphonate use (OR, 15.33 [95% CI 3.06-76.90]; P < 0.001). Duration of bisphosphonate use was longer in subtrochanteric/shaft cases compared to both hip fracture controls groups (P = 0.001). Conclusions We found a significantly greater proportion of patients with subtrochanteric/shaft fractures to be on long-term bisphosphonates than intertrochanteric/femoral neck fractures. Bisphosphonate use was highly associated with a unique X-ray pattern. Further studies are warranted.