title: Thoracic cage plasticity in prepubertal New Zealand white rabbits submitted to T1-T12 dorsal arthrodesis: computed tomography evaluation, echocardiographic assessment and cardio-pulmonary measurements.
abstract: OBJECTIVE
  We aimed to describe the morphological changes in the thoracic cage and spinal column induced in New Zealand White (NZW) prepubertal rabbits subjected to dorsal arthrodesis and observed at skeletal maturity by computed tomography (CT) scans. This was done to evaluate the plasticity of the thoracic cage of rabbits with non-deformed spine, by highlighting its modifications after spinal arthrodesis. Emogas data analysis, echocardiographic assessment and cardio-pulmonary measurements completed the evaluation.
  
  
  METHODS
  Surgery was performed in 16 female rabbits, 6 weeks old. Nine were subjected to T1-T12 dorsal arthrodesis, while seven were sham-operated. Surgery involved the implant of two C-shaped stainless steel bars and heterologous bone graft. CT scans were performed before surgery, 2, 6 and 12 months after surgery. One week after the last CT scan, echocardiographic and emogas evaluations were performed.
  
  
  RESULTS
  Chest depth (8%), thoracic kyphosis (ThK) (23%), dorsal and ventral length of the thoracic spine (11%) and sternal length (7%) were significantly reduced in operated compared to sham-operated rabbits. Mean values ± standard deviation (SD) of PaCO2, PaO2 and sO2 were not significantly different. Mean values ± SD of echocardiographic measurements were not significantly different between the two groups of rabbits, except for thickness of the interventricular septum in systole, contractile capacity of the left ventricle and ejection fraction.
  
  
  CONCLUSIONS
  T1-T12 dorsal arthrodesis in prepubertal NZW rabbits with non-deformed spine induced changes of the thoracic cage morphology. However, those changes are source of cardio-pulmonary complications not severe enough to reproduce a clinical picture comparable to thoracic insufficiency syndrome in humans.
authors.affiliation: Service de Chirurgie Infantile, Centre Hospitalière Universitaire Estaing, 1 Place Lucie et Raymond Aubrac, 63003, Clermont Ferrand, France. canavese_federico@yahoo.fr
authors.forename: Federico
authors.initials: F
authors.lastname: Canavese
authors.forename: Alain
authors.initials: A
authors.lastname: Dimeglio
authors.forename: Marco
authors.initials: M
authors.lastname: Stebel
authors.forename: Marco
authors.initials: M
authors.lastname: Galeotti
authors.forename: Bartolomeo
authors.initials: B
authors.lastname: Canavese
authors.forename: Fabio
authors.initials: F
authors.lastname: Cavalli
mesh_terms: D000818:Animals; D005260:Female; D007738:Kyphosis / Q000000981:diagnostic imaging*; D011817:Rabbits; D011859:Radiography; D013123:Spinal Fusion / Q000379:methods*; D013249:Sternum / Q000000981:diagnostic imaging*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D035441:Thoracic Wall / Q000000981:diagnostic imaging*