Traumatic Injuries (Week 7) Flashcards
what is the mechanism of an ankle sprain?
a combination of high force and high strain in a ligament results in failure
wha position of the ankle results in high strain of the lateral ligaments? (2 points)
- combination of inversion and internal rotation/forefoot adduction
- planter flexion can increase the strain further, but does not have to be present for failure strain
which ligaments on the lateral side of the ankle fail ?
- ATFL (tensile strength much lower than the other lateral ligaments)
- CFL (less often, high load and high ROM strain)
state 4 risk factors of ankle sprain
1) previous ankle sprain
2) poor ankle stability
3) poor ankle muscle strength
4. nature of the sport
explain how previous ankle sprains can be a risk factor for future sprain
properties of healed ligaments are altered - likely to have reduced stiffness and strength
explain how poor ankle stability is a risk factor for ankle sprain (2 points)
- increased laxity (passive range of motion)
- poor proprioception results in slow or inappropriate alterations in balance
explain how poor ankle strength is a risk factor for ankle sprain
reduced ability of muscles to absorb forces to control movement of the ankle
state 5 preventative techniques of ankle sprains
1) ankle braces
2) mobility exercises
3) balance board exercises
4) strapping and taping
5) strengthening exercises
what is the purpose of strapping and taping as a preventative mechanism of injury?
helps with proprioceptive feedback from that joint rather than providing mechanical support
explain the ‘contact mechanism’ of an ACL sprain
have an external contact with which forces the knee into an extreme valgus position, which stretches the MCL, which pulls the medial meniscus, which then causes a change in knee orientation and support causes the knee to twist, which ruptures the ACL
how does the damage to the lateral meniscus occur during ACL ruptures?
compression
what is the position of the foot during contact ACL ruptures
in contact with the ground
what two types of motions cause non-contact ACL ruptures
pivot - fixed foot and rotation results in excessive rotation and valgus torque
landing - insufficient knee flexion and weak hamstring result in excessive anterior force
explain further the landing cause of a non-contact ACL rupture
landing at an extended knee already puts a lot of strain on the ACL. combining this with weak hamstring muscles plus any degree of valgus will cause knee twist and fail of the ACL
state 3 risk factors of ACL ruptures
1) sex
2) previous injury
3) poor neuromuscular control
explain how females are at higher risk of an ACL rupture
anatomical, hormonal effect on tissue properties, knee control
explain, using 2 points, how poor neuromuscular control increases the chances of an ACL rupture
- imbalance in functional strength of quads and hamstrings (stronger quads bring the tibia forward)
- valgus collapse of the knee on jump landing tasks due to poor control of hip abductors
explain the use of a ‘neuromuscular training programme’ as a warm-up (5 points)
1) usually in the form of a warm-up
2) aim to improve the strength in the key muscles
3) appropriate muscle activation
4) focus on movement quality
5) improving balance
are ‘neuromuscular training programmes’ in warm-ups useful? (2 points)
- shown to be effective in controlled trials by reducing risk factors
- have to be viewed as performance enhancing as well to be implemented in practice
during what activities is a hamstring tear most likely to occur?
running, sprinting, kicking, extreme stretching?
what percentage of rugby hamstring tears are due to running?
68%
the long head of the bicep femoris is most commonly torn, but why?
due to the combination of origins on the ischial tuberosity and linea aspera of femur, and both inserting on the lateral condyle of the tibia, it ends up being the most strained. and having two heads, the control of that muscle is more complicated than the other hamstring muscles
state 4 risk factors for hamstring strains
1) low hamstring strength
2) short fascicle strength
3) flexibility
4) exercise technique
what exercise is being implemented across many sports in order to prevent hamstring strains?
Nordic hamstring exercise
what is the issue with the Nordic hamstring exercise? (3 points)
1) uptake in many sports is low
2) hamstring incidence remains high
3) highlights the importance of effective implementation strategies
