Question 1

Which type of bone tissue is laid down where no bone tissue has existed before, and comprises of several types of bone that differ morphologically, physiologically and in their mechanical properties?

Accepted Answer

B

Question 2

Because of its rapid growth and its high cell-to-bone volume ratio, it is believed that the purpose of _______bone is to provide a mechanical support to a fractured bone by way of splint.

Accepted Answer

Woven bone is characterized by its rapid growth and high cell-to-bone volume ratio, making it an ideal candidate for providing mechanical support to a fractured bone by forming a splint-like structure. Secondary bone is formed from the remodeling of primary bone and is not as rapidly formed as woven bone. Mononuclear bone is a term used to describe bone cells with a single nucleus and is not a commonly used term in bone physiology. Primary bone is formed during development and growth and is typically replaced by secondary bone during remodeling.

Question 3

From a mechanical perspective bone fails secondary to shear, tension, compression, bending, torsion, or combined loading and the fracture morphology reflects the failure mode. In a transverse fracture what is the common failure mode?

Accepted Answer

In a transverse fracture, the bone breaks horizontally in a straight line, and typically occurs due to bending loads. Bending loads cause tension on the outside of the curve and compression on the inside, leading to failure in the form of a transverse fracture.

Question 4

From a mechanical perspective bone fails secondary to shear, tension, compression, bending, torsion, or combined loading and the fracture morphology reflects the failure mode. In a diaphyseal impaction fracture what is the common failure mode?

Accepted Answer

Diaphyseal impaction fractures typically result from axial compression loads, where the force is applied along the axis of the bone, leading to a shortening or impaction of the bone structure.

Question 5

The cross sectional area and distribution of bone about the neutral axis affect the bone's mechanical behaviour, specifically affecting the bones resistance to bending moments. A bone with greater resistance to bending moments is said to have a greater ___________.

Accepted Answer

The answer of The cross sectional area and distribution of...

Question 6

Due to its lack of vascular, nerve and lymphatic supply, articular cartilage is dependent on exchange of _______________ for nutrients, oxygen and repair.

Accepted Answer

Articular cartilage is dependent on exchange of synovial fluid for nutrients, oxygen and repair.

Question 7

A progressive disorder of the joints caused by gradual wearing of cartilage with eventual exposure of subchondral bone which leads to the development of bony spurs and cysts at the margins of the joints is typically referred to as____________.

Accepted Answer

The description fits the characteristics of osteoarthritis, which is a common type of arthritis that occurs when the cartilage in joints deteriorates over time, leading to bone-on-bone contact and the development of bony growths at the edges of joints. Osteochondritis refers to inflammation or injury of both cartilage and underlying bone, whereas reactive and psoriatic arthritis have different causes and mechanisms of development.

Question 8

Tendinopathies and incidence of tendon rupture have a propensity to increase with age. Which of the following statements regarding the aging tendon are true?

Accepted Answer

As tendons age, they become more compliant due to the loss of viscosity and increase in collagen cross-bridges. This increased compliance may slow the rate of force development in the muscle, affecting the time necessary to decelerate a moving limb. Choice A is partially correct, but the decreased elastin makes the tendon less compliant, not more compliant. Choice C is incorrect because decreased tendon compliance would actually lead to less time necessary to decelerate a moving limb because the tendon would not be able to store as much energy. Choice D is incorrect because decreased tendon compliance would result in smaller strains at any given force, not larger strains.

Question 9

Our muscle strength tends to peak between age 20 and 30 then plateaus until around age 50 where strength begins to decline. The strength loss between ages 20 and 70 has been estimated to be around, what percentage?

Accepted Answer

Muscle strength begins to decline around age 50 and the strength loss between ages 20 and 70 has been estimated to be around 30%.

Question 10

When there is a direct impact to a muscle, that muscle experiences a large compression force as it is compressed between the impacting object and the underlying bone. What is this type of direct impact injury called?

Accepted Answer

A contusion is a direct impact injury to a muscle caused by compression between an impacting object and underlying bone. A sprain is a stretching or tearing of ligaments, a bruise is a discoloration of the skin caused by bleeding underneath, and a hematoma is a swelling of blood within tissue.

Question 11

A muscular strain occurs when the load applied to a muscle exceeds the tissue tolerance and is most often associated with eccentric muscle activity. What two factors are positively correlated with the magnitude of tissue damage?

Accepted Answer

The number of fibers being contracted while under passive stretch and the rate of loading of the eccentric force are positively correlated with the magnitude of tissue damage in muscular strains. The other options (B and C) do not have a direct correlation with tissue damage in muscular strains. Option D is incorrect as there is a correlation between tissue damage and certain factors.

Question 12

A fatigued muscle has a reduced capacity for energy absorption during the early stages of muscle stretching, as compared to non-fatigued muscle (Mair et al., 1996)Thus, a fatigued muscle will_______ to absorb the same amount of energy.

Accepted Answer

A fatigued muscle has a reduced capacity for energy absorption during the early stages of muscle stretching, meaning it will not be able to absorb the same amount of energy as a non-fatigued muscle. This leads to the muscle undergoing greater lengthening as it cannot withstand the same level of force. So, choice C is the best answer.

Question 13

An intramuscular contusion is most problematic because the build up of fluid within the muscle sheath can lead to increased pressure within the muscle, known as?

Accepted Answer

Compartment syndrome is a condition where there is increased pressure within a muscle compartment, which can lead to decreased blood flow to the muscles and nerves within that compartment. In the case of an intramuscular contusion, the build up of fluid within the muscle sheath can contribute to compartment syndrome. Strain refers to a muscle or tendon injury, DOMS (delayed onset muscle soreness) refers to muscle soreness that occurs 24-72 hours after exercise, and contusion refers to a muscle bruise. None of these fully explain the potential consequences of an intramuscular contusion.

Question 14

It has been hypothesised that the hamstrings are most susceptible to injury during which phase of running.

Accepted Answer

The terminal swing phase of running is when the hamstrings are most vulnerable to injury due to the high eccentric demands of the muscle. During this phase, the hamstrings act to slow down the swinging leg before foot strike, which requires them to lengthen while under tension. This combination of lengthening and tension puts the hamstrings at risk for strain or tear injuries.

Question 15

This condition and may be caused by the muscles of the tensor fascia lata or gluteus maximus translating back and forth over the greater trochanter.

Accepted Answer

The condition of the muscles of the tensor fascia lata or gluteus maximus translating back and forth over the greater trochanter is known as snapping hip. Runners hip and jumpers hip are not terms commonly used to describe this condition. Trick hip is not a recognized medical term.

Question 16

As the knee reaches full extension the tibia externally rotates to lock the knee into the meniscus, the ACL acts to resist hyperextension and becomes taught. What is the common anatomical term for this phenomenon?

Accepted Answer

The screw home mechanism is the common anatomical term for the phenomenon where the tibia externally rotates to lock the knee into the meniscus as the knee reaches full extension. The ACL also acts to resist hyperextension and becomes taught during this process.

Question 17

Which knee ligament protects the knee against valgus directed forces and consists of three layers; superficial, deep, and posterior.

Accepted Answer

The MCL (medial collateral ligament) is located on the inner side of the knee and protects against valgus (side-to-side) forces. It consists of three layers: superficial, deep, and posterior. The ACL (anterior cruciate ligament) protects against anterior translation of the tibia and is located in the center of the knee. The PCL (posterior cruciate ligament) protects against posterior translation of the tibia and is located in the back of the knee. The LCL (lateral collateral ligament) is located on the outer side of the knee and protects against varus (side-to-side) forces.

Question 18

Jumper's knee is a common tendinopathy in volleyball, basketball and netball caused by chronic overuse of the __________.

Accepted Answer

Jumper's knee is caused by chronic overuse of the quadriceps muscles, particularly the patellar tendon. The other muscles listed are not directly involved in this condition.

Question 19

The knee is a simple hinge joint that is subject to compression and shear forces during everyday activities. Which of the following anatomical facts regarding the knee joint is correct?

Accepted Answer

The popliteus muscle is responsible for initiating flexion of the knee by unlocking it from the extended position.

Question 20

The bone-patellar tendon-bone graft is considered the gold standard in ACL reconstruction but it does have its disadvantages, which include:

Accepted Answer

The bone-patellar tendon-bone graft can cause anterior knee pain and discomfort when kneeling, which may last for a year or more.

Quiz 2: Njuries in Sport: How the Body Behaves Under Load