Material properties are related to stress fracture callus and porosity of cortical bone tissue at affected and unaffected sites.
Stress fractures are overuse injuries of bone that affect elite athletes and military recruits. One response of cortical bone to stress fracture is to lay down periosteal callus. The objectives of this study were to determine if material properties are different among bones with different stages of stress fracture callus, at both a callus site and at a distal site. Cortical specimens were mechanically tested to determine their stress-strain response. Material property differences were examined using nonparametric and regression analyses. At the callus site, material properties were low during the earliest stages of callus, higher with increasing callus maturity, but dropped at the late stage of callus. At the distal site, the material properties were low during early stages of callus and approached, or returned to, those of bones without callus during the late stages of callus. The effects of stress fracture and bone callus are not limited to the focal site of stress fracture.
Entwistle
Rachel C
RC
J.D. Wheat Veterinary Orthopedic Research Laboratory, School of Veterinary Medicine, Stover Lab, University of California-Davis, 1285 Veterinary Drive, Davis, California 95616, USA. rachel.entwistle@gmail.com
Sammons
Sara C
SC
Bigley
Robert F
RF
Hazelwood
Scott J
SJ
Fyhrie
David P
DP
Gibeling
Jeffery C
JC
Stover
Susan M
SM
D000818:Animals; D001696:Biomechanical Phenomena; D002146:Bony Callus / Q000000981:diagnostic imaging / Q000473:pathology*; D004195:Disease Models, Animal; D018450:Disease Progression; D005260:Female; D015775:Fractures, Stress / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary*; D006736:Horses / Q000502:physiology*; D006811:Humerus / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D010521:Periosteum / Q000000981:diagnostic imaging / Q000473:pathology; D011859:Radiography; D012044:Regression Analysis