title: Emu model of full-range femoral head osteonecrosis induced focally by an alternating freezing and heating insult.
abstract: The emu, a large bipedal bird with hip joint biomechanics similar to humans, was used to establish an experimental model of femoral head osteonecrosis and subsequent femoral head collapse. Focal lesions were induced in 20 adult male emus using an alternating liquid nitrogen freezing and radiofrequency heating insult. At 2, 4, 8, 12 and 16 weeks post-surgery, hip magnetic resonance imaging (MRI) was performed. Before the emus were sacrificed, barium sulphate was infused to the lower extremity to study blood vessel distribution patterns. Femoral samples were scanned by micro-computed tomography (micro-CT) and evaluated histologically. Hip MRI showed changes from broad oedema to femoral head collapse. Emus developed a crippled gait from post-operative week 6. Micro-CT scans and histology showed human-like osteonecrotic changes with an impaired local blood supply. The protocol resulted in consistent full-range osteonecrosis of the femoral head that may serve as a model for testing potential treatments.
authors.affiliation: Orthopaedic Research Institute, General Hospital of Chinese People's Liberation Army, Beijing, China.
authors.forename: M
authors.initials: M
authors.lastname: Fan
authors.forename: J
authors.initials: J
authors.lastname: Peng
authors.forename: A
authors.initials: A
authors.lastname: Wang
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: B
authors.initials: B
authors.lastname: Liu
authors.forename: Z
authors.initials: Z
authors.lastname: Ren
authors.forename: W
authors.initials: W
authors.lastname: Xu
authors.forename: J
authors.initials: J
authors.lastname: Sun
authors.forename: Lx
authors.initials: L
authors.lastname: Xu
authors.forename: D
authors.initials: D
authors.lastname: Xiao
authors.forename: L
authors.initials: L
authors.lastname: Qin
authors.forename: S
authors.initials: S
authors.lastname: Lu
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.forename: Q Y
authors.initials: QY
authors.lastname: Guo
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D004195:Disease Models, Animal; D020312:Dromaiidae; D005270:Femur Head / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D005271:Femur Head Necrosis / Q000000981:diagnostic imaging / Q000473:pathology; D005615:Freezing / Q000009:adverse effects; D005684:Gait; D006361:Heating / Q000009:adverse effects; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D010020:Osteonecrosis / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed