Lower Extremity Joint Moments

[Karl Grainger]

I am currently working on a project examining joint moments in cycling but having a problem finding some core information to help with the calculations. Winter (1990, p.56) is a brilliant text and has helped with values in the sagittal plane, however, in the frontal plane I am struggling to find 'accurate' definitions of the following:


- lateral position of knee joint - I'm currently taking the mid point of medial and lateral epicondyle


- lateral position of ankle joint - again, currently using mid point of medial and lateral malleolus


- hip joint centre. For sagittal location I have used the mid point of greater trochanter and ASIS. What would be an appropriate position in the frontal plane?


- Centre of mass of foot, shank and thigh mediolaterally. Winter provides where the CoM is as a percentage of the length of the limb, but where would the CoM be laterally? For the foot this is clearly a problem as the foot is 'larger' medially, and hence the CoM is more medial.


- Radius of gyration - similar to the CoM, whereabouts would be a good location for it in foot, shank and thigh


Oh and to add to the story, we're undertaking the research in children, so any modified values for CoM / Radius of Gyration in children in Sagittal and Frontal planes would be really useful.


I'd really appreciate any help from anyone out there. I have read research into adults that must have used the above values, but I cannot find the raw data anywhere.

karl.grainger@brunel.ac.uk

[Hendrik Reimann]

Re: Lower Extremity Joint Moments

For the hip joint center, check [1], for the segment centers of mass and radii of gyration, check [2].

The kids part is trickier. We used [3] for infants, but their sample only went up to 1.5 years old. For anything above toddler age, you should be fine in using values for grown ups. A difference of a centimeter or two in a segment CoM or RoG doesn't have a hugely distorting effect on the resulting torque estimates.


[1] Bell, L., Pedersen, R., & Brand, A. (1990). A comparison of the accuracy of several hip center location prediction methods. Journal of Biomechanics, 23(6), 617–621.
[2] Dumas, R., Chèze, L., & Verriest, J.-P. (2007). Adjustments to McConville et al. and Young et al. body segment inertial parameters. Journal of Biomechanics, 40(3), 543–53. doi:10.1016/j.jbiomech.2006.02.013
[3] Schneider, K., & Zernicke, R. F. (1992). Mass, Center of Mass, and Moment of Inertia Estimates for Infant Limb Segments. Journal of Biomechanics, 25(2), 145–148.

[Bmsw GNP]

Re: Lower Extremity Joint Moments

Hi,

You can refer, Winter book. It has given methods how to calculate the Lower Extremity Joint Moments. [Go through chap. 4-5-6]

THnaks

Regards,
Gunjan

For the hip joint center, check [1], for the segment centers of mass and radii of gyration, check [2].

The kids part is trickier. We used [3] for infants, but their sample only went up to 1.5 years old. For anything above toddler age, you should be fine in using values for grown ups. A difference of a centimeter or two in a segment CoM or RoG doesn't have a hugely distorting effect on the resulting torque estimates.


[1] Bell, L., Pedersen, R., & Brand, A. (1990). A comparison of the accuracy of several hip center location prediction methods. Journal of Biomechanics, 23(6), 617–621.
[2] Dumas, R., Chèze, L., & Verriest, J.-P. (2007). Adjustments to McConville et al. and Young et al. body segment inertial parameters. Journal of Biomechanics, 40(3), 543–53. doi:10.1016/j.jbiomech.2006.02.013
[3] Schneider, K., & Zernicke, R. F. (1992). Mass, Center of Mass, and Moment of Inertia Estimates for Infant Limb Segments. Journal of Biomechanics, 25(2), 145–148.

[Dustin Bruening]

Re: Lower Extremity Joint Moments

The following two studies on hip and ankle joint centers were performed on children:
- Harrington, M. E., et al. "Prediction of the hip joint centre in adults, children, and patients with cerebral palsy based on magnetic resonance imaging."Journal of biomechanics 40.3 (2007): 595-602.
- Bruening, D.A. et al. "A simple, anatomically based correction to the conventional ankle joint center." Clinical Biomechanics 23.10 (2008): 1299-1302.

Also, in most cases, foot inertial parameters have very little effect on joint moments, so getting those perfectly accurate is not as critical.
Best, Dustin