Biology Lecture Week 7 - Uncontrollable Factors Flashcards
Factors include those that uncontrollable because of genetic or congential reasons, but can come about because of injury or illness are …
- age
- gender
- musculoskeletal deformities such as pes planus (flat
feet) and leg length discrepancies (Bartlett, 1999)
What uncontrollable factors may have a source that is
intrinsic or genetic, but can be modified within limits ?
- coordination
- incorrect body weight
- poor posture
- lack of joint mobility
- lack or imbalance of muscle strength
The average adults bone mass peaks between …
20 and 40 years of age
The average reductions in bone properties per decade from 20 years old onwards are ?
5 & 9% for ultimate tensile stress and strain, and 12% for energy absorption to failure
After 30 years old , tendons are less resistant to …
tension than bone whereas before this age avulsion fractures are a higher risk
When considering the risk of injury to older athletes,
there is a need to differentiate between the effects of ageing and those of decreased physical
activity. For instance, exercise may reduce the decline in strength of the ACL by up to …
50% and overall it has more of a beneficial side than detrimental
Overuse injuries are most prevalent in older athletes,
often with wear and tear effects such as …
osteoarthritis
Older athletes are more likely to re-injure themselves
after returning to sport because their longer sports
careers mean they have more previous injuries.
Changes in muscle structure occur with ageing …
that lead to reduced performance in performance tests
Ligaments: decrease in
failure strength and energy
absorption before failure,
which leads to an increase in …
joint stiffness and injury
susceptibility
Bone: atrophy. Mass and
size decrease through loss of …
equal proportions of matrix
and mineral content
What differences mean there is an increased risk in women ?
- a wider pelvis (and resulting genu varum with altered hip and knee
loading - smaller bones and surfaces (female bone mass is typically 30% less
than males) - greater rate of loss of bone with age (osteoporosis)
- less muscle mass and higher fat content
What are the reasons for abnormal gait ?
- Neurological disorders
- Skeletal disorders
- Muscular disorders
- Pain
- Age
- Personality
Describe the two different types of leg length differences concerning biomechanical abnormalities ?
- anatomical
difference, i.e. the bones are actually different lengths - a functional difference. This means the legs
appear to be different lengths (e.g. by looking at the levelness of the pelvis) but this can be due to foot
architecture or frontal plane displacement of the leg
joints
Describe Genu Varum …
(bow leggedness) or genu valgum (knock knees). These can clearly affect gait and other movements. Severe cases can be due to congenital or dietary problems (e.g. rickets) but in addition some sports (e.g. horse riding) can produce similar effects
What is the Trendelenberg gait problem ?
arising from weak hip abductors (e.g. gluteus medius). The pelvis is not kept in a supported position
during the stance phase of walking, and thus the leg
has to be swung outwards in a movement known as hip-hitching. This is to
prevent the foot from contacting the ground
