Lowering Bone Stress Injury Risk by Understanding Loading Angle, Bone Strength, and Training Load

Links

URL: https://digital.wpi.edu/concern/etds/zs25xd78g

Abstract and keywords

Background: Bone Stress Injuries (BSI) leads to structural fatigue, localized bone pain, and in severe cases loss of bone function. Currently there is minimal research in understanding how foot loading and biomechanics contribute to high metatarsal strain and damage accumulation within the metatarsals of runners.

Methods: Utilizing computed tomographic images of the feet of 28 long distance runners (7 injured and 21 healthy) three-dimensional orthotropic models of the second, third, and fourth metatarsals at various loading angles relative to running. Maximum principal strain, minimum principal strain, von Mises stress, maximum principal stress, minimum principal stress, and strained volume of the midshaft and whole metatarsal was collected using the 90th percentile values collected from each element. We compared the effect of loading angle and injury status from this analysis to understand how different associated risk factors affect the mechanical behavior of the metatarsals. These calculations made using the feet of injured and healthy runners along with an in-depth analysis of the self-identified training data was used to understand the correlation between strain magnitude and strained volume in the metatarsals in competitive athletic runners.

Results: Our evaluation of the effect of metatarsal loading angle concluded by loading metatarsals to a more axially, would significantly decrease in strain in metatarsals (p<0.001).Our comparison of the healthy foot of the injured versus healthy runners found that there was an excess amount of strained volume within the cortical bone region of healthy feet of the injured runners (>17%). This translated to a large amount of damage accumulation within the metatarsal. This damage accumulation leaded to the imbalance within the bone remodeling process causes bones to weaken rapidly when loaded in excess. Our injured runners surpassed the theoretical loading capacities of their bone by running more than 60 km a week (BCLR of >1.0), and we found biomechanical and demographics are important factors used to understand the risk factors associated with BSI.

Conclusions: This study uses an integrated approach in understanding BSI by understanding biomechanics of metatarsal loading through changes in loading angle, the structural mechanics of bone in injured and healthy runners and created bone cumulative loading ratio (BCLR) to understand the possible modifications plausible in lower the risk of BSI. The BCLR represents a promising concept to assess BSI risk, relative to the training load and individual bone structure. In the future, predictive models such as the ones developed here could help reduce the risk of BSI through managing biomechanics, training load, and personal risk factors.

Keywords: finite element modeling; bone stress injuries; metatarsal; strained volume; cumulative loading; training volume; bone strength; loading angle

Cited Works (23)

Year	Entry
2009	Rincón-Kohli L, Zysset PK. Multi-axial mechanical properties of human trabecular bone. Biomech Model Mechanobiol. June 2009;8(3):195-208.
1975	Reilly DT, Burstein AH. The elastic and ultimate properties of compact bone tissue. J Biomech. 1975;8(6):393-405.
2017	Fung A. Experimental Validation of Finite Element Predicted Bone Strain in the Human Metatarsal [Master's thesis]. Calgary, AB: University of Calgary; April 2017.
2001	van der Linden JC, Homminga J, Verhaar JAN, Weinans H. Mechanical consequences of bone loss in cancellous bone. J Bone Miner Res. March 2001;16(3):457-465.
1998	Taylor D. Fatigue of bone and bones: an analysis based on stressed volume. J Orthop Res. March 1998;16(2):163-169.
2008	Sharir A, Barak MM, Shahar R. Whole bone mechanics and mechanical testing. Vet J. July 2008;177(1):8-17.
2015	Oftadeh R, Perez-Viloria M, Villa-Camacho JC, Vaziri A, Nazarian A. Biomechanics and mechanobiology of trabecular bone: a review. J Biomech Eng. January 2015;137(1):010802.
1997	Cavanagh PR, Morag E, Boulton AJM, Young MJ, Deffner KT, Pammer SE. The relationship of static foot structure to dynamic foot function. J Biomech. March 1997;30(3):243-250.
1994	Prendergast P, Taylor D. Prediction of bone adaptation using damage accumulation. J Biomech. August 1994;27(8):1067-1076.
1989	Caler WE, Carter DR. Bone creep-fatigue damage accumulation. J Biomech. 1989;22(6-7):625-635.
1979	Stokes IAF, Hutton WC, Stott JRR. Forces acting on the metatarsals during normal walking. J Anat. 1979;129(pt 3):579-590.
2021	Loundagin LL, Pohl AJ, Edwards WB. Stressed volume estimated by finite element analysis predicts the fatigue life of human cortical bone: the role of vascular canals as stress concentrators. Bone. February 2021;143:115647.
2021	Haider IT, Lee M, Page R, Smith D, Edwards WB. Mechanical fatigue of whole rabbit-tibiae under combined compression-torsional loading is better explained by strained volume than peak strain magnitude. J Biomech. June 9, 2021;122:110434.
2006	Milner CE, Ferber R, Pollard CD, Hamill J, Davis IS. Biomechanical factors associated with tibial stress fracture in female runners. Med Sci Sports Exer. February 2006;38(2):323-328.
2021	Popp KL, Ackerman KE, Rudolph SE, Johannesdottir F, Hughes JM, Tenforde AS, Bredella MA, Xu C, Unnikrishnan G, Reifman J, Bouxsein ML. Changes in volumetric bone mineral density over 12 months after a tibial bone stress injury diagnosis: implications for return to sports and military duty. Am J Sports Med. January 2021;49(1):226-235.
1980	Cavanagh PR, Lafortune MA. Ground reaction forces in distance running. J Biomech. 1980;13(5):397-406.
2010	Lieberman DE, Venkadesan M, Werbel WA, Daoud AI, D’Andrea S, Davis IS, Mang’Eni RO, Pitsiladis Y. Foot strike patterns and collision forces in habitually barefoot versus shod runners. Nature. January 28, 2010;463(7280):531-535.
2007	van Gent RN, Siem D, van Middelkoop M, van Os AG, Bierma-Zeinstra SMA, Koes BW. Incidence and determinants of lower extremity running injuries in long distance runners: a systematic review. Br J Sports Med. August 2007;41(8):469-480.
2006	Hadjidakis DJ, Androulakis II. Bone remodeling. Annals NY Acad Sci. December 2006;1092(1):385-396.
2010	Eriksen EF. Cellular mechanisms of bone remodeling. Rev Endocr Metab Disord. December 2010;11(4):219-227.
2001	Zioupos P, Currey JD, Casinos A. Tensile fatigue in bone: are cycles-, or time to failure, or both, important? J Theo Biol. June 7, 2001;210(3):389-399.
2001	Cowin SC, ed. Bone Mechanics Handbook. 2nd ed. Boca Raton, FL: CRC Press; 2001.
1998	Rho J-Y, Kuhn-Spearing L, Zioupos P. Mechanical properties and the hierarchical structure of bone. Med Eng Phys. 1998;20(2):92-102.

Cited By (1)

Year	Entry
2025	Nguyen C. A Probabilistic Method to Model Progressive Metatarsal Fatigue Failure and Microdamage Accumulation [Master's thesis]. Worcester, MA: Worcester Polytechnic Institute; July 2025.