Teriparatide improves bone quality and healing of atypical femoral fractures associated with bisphosphonate therapy

• Published in: Bone (New York, N.Y.) Vol. 52; no. 1; pp. 360 - 365
• Main Authors: Chiang, Cherie Ying, Zebaze, Roger M.D., Ghasem-Zadeh, Ali, Iuliano-Burns, Sandra, Hardidge, Andrew, Seeman, Ego
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.01.2013; Elsevier
• Subjects: Aged; Atypical femur fractures; Biological and medical sciences; Bisphosphonates; Bone (cortical); Bone density; Bone Density Conservation Agents - pharmacology; Bone Density Conservation Agents - therapeutic use; Bone healing; Bone loss; Bone remodelling; Bones, joints and connective tissue. Antiinflammatory agents; Computed tomography; Computer programs; Diphosphonates - adverse effects; Female; Femoral Fractures - chemically induced; Femur; Fracture Healing - drug effects; Fractures; Fundamental and applied biological sciences. Psychology; High resolution computed tomography; Humans; Injuries of the limb. Injuries of the spine; Male; Medical sciences; Mineralization; Orthopedics; Osteoporosis; Pain; Parathyroid hormone; Pharmacology. Drug treatments; Prospective Studies; Radius; Sex; software; Teriparatide; Teriparatide - pharmacology; Teriparatide - therapeutic use; Tibia; Traumas. Diseases due to physical agents; Vertebrates: anatomy and physiology, studies on body, several organs or systems; High resolution computed tomography; Osteoporosis; Bisphosphonates; Atypical femur fractures; Teriparatide; Femur; High resolution; Antiosteoporotic; Radiodiagnosis; Diseases of the osteoarticular system; Fracture; Trauma; Treatment; Antiosteoclastic agent; Morphology; Quality; Medical imagery; Atypical; Computerized axial tomography; Bone; Cicatrization
• ISSN: 8756-3282; 1873-2763; 1873-2763
• DOI: 10.1016/j.bone.2012.10.006

Bone remodelling suppressants like the bisphosphonates reduce bone loss and slow progression of structural decay. As remodelling removes damaged bone, when remodelling suppression is protracted, bone quality may be compromised predisposing to microdamage accumulation and atypical femoral fractures. The aim of this study was to determine whether teriparatide therapy assists in fracture healing and improves bone quality in patients with bisphosphonate associated atypical femoral fractures. A prospective study was conducted involving 14 consecutive patients presenting during 2years with atypical femoral fracture. All patients were offered teriparatide therapy unless contraindicated. Age and sex matched control subjects without fragility fractures or anti-resorptive treatment were recruited. High resolution peripheral micro-computed tomography (HRpQCT) scans of the distal radius and distal tibia were analysed for their cortical bone tissue mineralisation density using new software (StrAx1.0, StrAxCorp, Australia) at baseline and 6months after teriparatide. Administration of 20μg of teriparatide subcutaneously daily for 6months to 5 of the 14 patients was associated with 2–3 fold increase in bone remodelling markers (p=0.01) and fracture healing. At the distal radius, the proportion of less densely mineralised bone increased by 29.5% (p=0.01), and the proportion of older, more densely mineralised bone decreased by 16.2% (p=0.03). Similar observations were made at the distal tibia. Of the nine patients managed conservatively or surgically, seven had poor fracture healing with ongoing pain, one sustained a contralateral atypical fracture and one had fracture union after 1year. Teriparatide may assist in healing of atypical fractures and restoration of bone quality. ► Bisphosphonates suppress bone remodelling, which can lead to microdamage accumulation and atypical femoral fractures. ► Teriparatide given to five patients with atypical fractures was associated with an increase in bone remodelling markers and fracture healing. ► The volume of less densely and more heterogeneously mineralised bone increased and the proportion of older, more densely mineralised bone decreased. ► Teriparatide may assist in healing of atypical fractures and restoration of bone quality.