Can some physical therapy and manual techniques generate potentially osteogenic levels of strain within mammalian bone?
OBJECTIVE
Although physical therapy techniques are used to alleviate pain and stiffness in joint injuries, whether these methods are capable of affecting bone is unknown. For example, can these techniques potentially influence bone formation or resorption? To begin exploring this possibility, this study investigated the ability of 4 manual techniques to generate levels of compressive strains that presumably can stimulate bone metabolism.


METHODS
Six 3,4 metacarpals from three 3-year-old Merino ewes were used.


METHODS
A rosette strain gauge was implanted onto the dorsomedial cortex of each ovine 3,4 metacarpal. Four different manual procedures were applied on 2 occasions on each metacarpal in vivo and ex vivo. Mean peak principal compressive strains were calculated for each technique.


RESULTS
Levered bending produced greater mean peak compressive strains than almost all other manual procedures tested in vivo or ex vivo.


CONCLUSIONS
Manual levered bending created levels of compressive strain similar in magnitude to those created by mechanical devices used in previous animal experiments to induce new bone formation (osteogenesis). This animal model appears to be suitable for investigating the effects of manually applied procedures on bone and may establish whether manual techniques can stimulate bone formation.
Wilson
A W
AW
School of Human Biosciences, Faculty of Health Sciences, La Trobe University, Bundoora, Victoria, Australia 3083. a.wilson@latrobe.edu.au
Davies
H M
HM
Edwards
G A
GA
Grills
B L
BL
D000704:Analysis of Variance; D000818:Animals; D001696:Biomechanical Phenomena; D016723:Bone Remodeling / Q000502:physiology; D008663:Metacarpus / Q000254:growth & development / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology*; D026741:Physical Therapy Modalities / Q000379:methods*; D012756:Sheep; D013314:Stress, Mechanical