Levothyroxin inhibits heterotopic ossification: an experimental study in rabbits.
BACKGROUND
Heterotopic ossification is a common complication of surgery or trauma.


OBJECTIVE
To investigate the efficacy of levothyroxin in inhibition of heterotopic ossification.


METHODS
Heterotopic ossification was induced in 36 rabbits in three identical groups by injecting 2 mL of bone marrow in right thigh. To prevent heterotopic ossification, levothyroxin (20 microg/kg) was administered orally daily for 4 weeks to two groups of adult rabbits: group A (preload)--starting 1 week preceding bone marrow injection; group B--started on day of injection; and group C--control group (no levothyroxin) in a rabbit model. After 5 weeks the rabbits were evaluated by radiographs for evidence of ossification. At the end of the study histologic samples were taken from all the thighs.


RESULTS
Imaging and histologic studies showed, with statistical significance, almost complete prevention of heterotopic ossification in group A (preload) and a marked decrease in group B, when compared with the controls.


CONCLUSIONS
Levothyroxin demonstrated efficacy in preventing heterotopic ossification.
Namazi
Hamid
H
Shiraz University of Medical Sciences, Shiraz, Iran. Namazih@sums.ac.ir
Mozaffarian
Kamran
K
D000284:Administration, Oral; D000818:Animals; D001707:Biopsy, Needle; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D007150:Immunohistochemistry; D018482:Muscle, Skeletal / Q000187:drug effects / Q000473:pathology*; D009999:Ossification, Heterotopic / Q000188:drug therapy* / Q000473:pathology* / Q000517:prevention & control; D011817:Rabbits; D011897:Random Allocation; D012016:Reference Values; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013974:Thyroxine / Q000008:administration & dosage*
D013974:Thyroxine