Biomechanics essay Flashcards
Introduction:
Restate the essay question and then provide an interpretation of it (don’t say I)
Say will be on footwear on a biomechanical level, which is the study of the structure, function and motion of the mechanical aspects of biological systems R. McNeill Alexander (2005),
focusing on angular kinematics – the study of rotational motion in the absence of forces, and angular kinetics the study of rotational motion with regard to the forces (D. Kleppner and R. Kolenkow, 1973)
Importance empathised on the profit margin of sport shoe companies h (Clinghan, R et al., 2008)
But more importantly how motion control shoes qualified by reduction in rear foot motion reduce ankle inversion injuries, anterior knee pain and plantar fasciitis, through medial posting and dual density (Clarke et al., 1983)
affect the athletic well being of individuals and professional athletes who depend on their performance and injury risk .( Barrett, J. and Bilisko, T., 1995.)
• Describe how the essay is going to answer the question
Text introduction of main paragraph 1?
Description of rear foot motion - As shown by figures 1 and 2 Rearfoot motion composes of heel stance resulting in supination of the ankle, which is defined by ankle inversion, adduction and plantar-flexion, the foot then progresses into midstance producing pronation which results in eversion, abduction and dorsi-flexion, resulting in propulsion at toe off.
Figure 3 shows the foot-ankle complex, which consists of the sub-talar which increases duration of impact – facilliatting frontal and transverse movement, the dissipation of momentum, as well as providing hardness for propulsion,
Also shown by figure 3 the talocrural joint allows sagital plane motion including dorsiflexion and platar flexion it is located, it is a hinge joint formed by the tibia, fibula and the talus.
Images for rear foot motion introduction for main paragraph 1?
Rearfoot motion graph:
In top right have “average values 8-10 degrees”
Time on x, rear foot angle on y
On y start on 5, bottom value is -10
Have steeped bell curve intercepting the line twice, and label maximum rear foot angle
Labelled right leg:
Block for calf, block for foot
Each has two circles within it joined up
Rearfoot angle formed by line going straight from bottom of calf one through top one, and then formed with the angle of of top calf one going through bottom calf one
Supination: (inversion, adduction, plantar flexion)
Foot tilted down on right side
Pronation: (pronation, abduction and doors flexion)
Foot tilted down on left side
Images for foot ankle complex on intro of main paragraph 1?
Have to look at slides,
Talocrural is top one
The subtalar is the bottom one
Text for argument 1 main paragraph 1?
Hreljac et al. (2000) evaluated lower extremity biomechanical and anthropometric variables in overuse injury potential in runners, comparisons drawn from runners who had sustained an overuse injury to those who had not
Kinetic and Kinematic Data was collected via filming subjects running over force platform at 4.m.s^-1.
Demonstrated lower velocity of pronation in those with previous injury (injury -289+/- 106) (injury free -334+/- 126) p = 0.08,
suggesting faster levels of pronation reduce chance of overuse injuries, motion control shoes may be detrimental to injury risk.
text for argument 2 main paragraph 1?
However, Luz et al (2017) investigated Patellofemoral pain the common overuse injury, and it’s correlation of rearfoot eversion, a component of pronation.
Kinematic data was obtained via a three dimensional motion analysis system, and it was found that greater rearfoot eversion has the potential to relate PFP persistence in runners, and that treatment to reduce eversion could modify the symptoms
Conclusion for main paragraph 1?
Taking into account both side of the literature, it is unclear of a decisive outcome on the value of motion control footwear.
The value of Hrelijac (2000) findings is decreased due to it’s grouping of injuries, small sample of 20, and the method being retrospective rather than prospective
However, Luz et al (2017) provides 54 subjects, and is a far more recent, hence more updated on current literature. However the study is cross sectional, only uses kinematic data and provides of a more insight on injury rehabilitation rather than prevention.
Introduction for main paragraph 2?
In biomechanical determination of injury variables the importance of prospective study is essential, as it allows the distinguishing between biomechanical values being a causative effect of the injury, and the likelihood of a healthy individuals biomechanical values resulting in injury and the precautions that can be taken to enhance performance and reduce risk of injury.
Text for argument 1 main paragraph 2?
Rice et al (2013), investigated ankle inversion risks in a prospective study of 145 male, injury-free recruits
Obtaining plantar pressure and kinematic variables,
eluded to no difference in peak eversion or eversion range of motion of those who did or didn’t get an ankle injury, whilst narrower bimalleolar breadth was associated with ankle injury.
Text for argument 2 main paragraph 2?
On the other hand, Willems et al (2005) underwent a study in which 223 physical education students static lower leg alignment as well as 3D kinematics and plantar pressure profiles was determined.
Over the next 6-18 months a physician collected all sporting injuries obtained by students.
It was found in those who were injured a maximum inversion velocity was observed so a longer time spent in pronation, signifying a reduction in pronation from motion control footwear is beneficial in injury prevention
Conclusion for main paragraph 2?
In comparison, both studies provide validity as they are both prospective, large sample sizes, and applied data collecting variables
However, neither data colleting method can account for the exercise, intensities and quantity forgone by the individuals throughout the prospective study, which may have far larger bearing on injury risk, foreshadowing the foot biomechanics.
In turn still rendering a clear answer anonymous.
Overall conclusion?
- The significance of findings that could be held to a gold standard would provide runners with less injury risk, hence a larger potential, but for now it is still unclear, and so are the implications
- Further study should analyse the biomechanical individual level of the athlete, hence a more appropriate footwear can be applied, providing a practical application for the athlete whilst providing data for further athletes showing similar biomechanics/sports, hence an implication of improved performance
- Also sports companies could validate their prices
- Therefore footwear implications for runners on the angular kinematic and kinetic level is undecided through the relevant literature, but the data collecting methods applied on the individual level would provide far more insight and practical application.
