Anatomy - Muscles and Movement

Question 1

What are the three types of muscle?

Answer 1

Smooth, cardiac and skeletal muscle. Slide 2

Question 2

What is the order of muscle structure, layer by layer?

Answer 2

Skeletal muscle
Fascicle
Muscle fibre
Myofibril
Actin and myosin. Slide 3

Question 3

Why does skeletal muscle appear ‘striped’ when viewed histologically?

Answer 3

From the overlapping of actin and myosin. Slide 4

Question 4

What has happened histologically when a muscle is strained?

Answer 4

Some muscle fibres have been torn. Slide 4

Question 5

There are 5 types of skeletal muscle, what are they?

Answer 5

Flat, fusiform, circular, pennate and quadrate. Slide 5

Question 6

What does longer muscle fibres allow to happen?

Answer 6

It has a greater potential range of shortening. Therefore a greater potential range of movement produced at the joint. Slide 5

Question 7

What is a flat skeletal muscle and an example?

Answer 7

With aponeurosis (sheet of fibrous tissue) it is muscle fibres which run parallel. e.g. external oblique muscle. Slide 5

Question 8

What is a fusiform skeletal muscle and an example?

Answer 8

It is a spindle shaped muscle, round thick muscle belly which tapers at the end, e.g. biceps brachii. Slide 5

Question 9

What is a circular skeletal muscle and an example?

Answer 9

It is circular muscle, e.g. orbicularis oculi. Slide 5

Question 10

What is a pennate skeletal muscle and an example?

Answer 10

It is feather like muscle e.g. deltoid. Slide 5

Question 11

What is a quadrate skeletal muscle and an example?

Answer 11

It is 4 sided and square shaped, e.g. rectus abdominus. Slide 5

Question 12

How do skeletal muscles move joints?

Answer 12

They have to span the joint and cross it. Slide 6

Question 13

Do muscles always connect to bone at insertion or origin?

Answer 13

No. Slide 7

Question 14

Do tendons which are attached to muscle, contract?

Answer 14

No. Slide 8

Question 15

What is an aponeurosis?

Answer 15

A flattened tendon, usually with flat muscles and attach to soft tissue rather than bone. Slide 8

Question 16

What does longus and brevis mean?

Answer 16

Longus - long

Brevis - short. Slide 10

Question 17

What part of the deltoid muscle extends the shoulder?

Answer 17

The posterior fibres move the shoulder back. Slide 11

Question 18

What part of the deltoid muscle abducts the shoulder?

Answer 18

The middle fibres. Slide 11

Question 19

What part of the deltoid muscle flexes the shoulder?

Answer 19

The anterior fibres. Slide 11

Question 20

What does the articular surface of a bone determine?

Answer 20

Determines the possible movement of that joint e.g. shoulder can circumduct due to shallow socket of the glenoid fossa in the scapula. Slide 12

Question 21

What are the clinical aspects of skeletal muscle?

Answer 21

Testing ability to move, muscle itself and nerves supplying it - can be tested by asking patient to carry out moves or reflexes. Slide 13

Question 22

What are the two main reflexes for skeletal muscle?

Answer 22

Stretch reflex and the flexion withdrawal reflex. Slide 14

Question 23

What is the flexion withdrawal reflex?

Answer 23

When we touch something that is potentially dangerous. Slide 14

Question 24

What are the deep tendon reflexes?

Answer 24

Biceps jerk, triceps jerk, knee jerk and ankle jerk. Slide 15

Question 25

How are the deep tendon reflexes tested?

Answer 25

A tendon hammer applies a brief sudden stretch to the muscle VIA its tendon. Slide 15

Question 26

What are the deep tendon reflexes doing when being tested?

Answer 26

Protecting the muscle against overstretching. Slide 15

Question 27

How do the deep tendon reflexes work?

Answer 27

Sensory nerve detects stretch. The synapse in the spinal cord communicates this to the motor nerves. Then the motor nerve passes the message for the muscle to contract. Slide 16

Question 28

What is the neuromuscular junction?

Answer 28

The synapse at the end of the motor neuron and the skeletal muscle. Slide 16

Question 29

What does a normal stretch reflex indicate is functioning normally?

Answer 29

The muscle, sensory nerve, motor nerve, spinal cord connections between the two neuromuscular junctions. Slide 17

Question 30

What are descending controls from the brain for during stretch reflexes?

Answer 30

Prevents a full leg kick, and a large reaction.

Question 31

What is muscle paralysis?

Answer 31

It is a muscle without a functioning more nerve supply, it cannot contract and would result in reduced tone (floppy feeling). Slide 18

Question 32

What is muscle spasticity?

Answer 32

Has an intact and functioning motor nerve, however the descending controls from the brain are not working. So it would have increase tone (feel tight). Slide 18

Question 33

What is muscle atrophy?

Answer 33

When the muscle 'wastes' away and muscle fibres shrink. This is due to inactivity. Slide 19

Question 34

What is hypertrophy?

Answer 34

Opposite of atrophy. The skeletal muscles enlarge. Slide 20

Question 35

Where are skeletal muscles found?

Answer 35

In the deep fascia with tough fibrous connective tissue covering it. Slide 21

Question 36

How is the muscle positioned in the deep fascia?

Answer 36

Separated into compartments by an invaginated deep fascia forming an intermuscular septum.

Question 37

What is the positives and negatives about the compartmentalisation of muscle?

Answer 37

They usually have a similar function and if there is an infection, it won't spread. However if there is an infection it tends to spread upwards throughout the compartment. Slide 22

Question 38

What are the 3 compartments in the thigh?

Answer 38

Anterior, medial and posterior. Slide 23

Question 39

What are the 3 compartments in the leg?

Answer 39

Anterior, posterior and lateral. Slide 23

Question 40

What are the 2 compartments of the arm?

Answer 40

Anterior and posterior. Slide 24

Question 41

What are the 2 compartments of the arm?

Answer 41

Anterior and posterior. Slide 24

Question 42

What is compartment syndrome?

Answer 42

Since the fascia creates an enclosed space, if there is a swelling or bleeding there, it creates pressure and affects the nerves and muscles. Slide 25

Question 43

How do you treat a compartment syndrome?

Answer 43

Preform a fasciotomy, which relieves the pressure. Slide 25

Question 44

Are the muscles that preform coughing, gagging, sneezing etc.. skeletal or smooth muscle?

Answer 44

Skeletal, you are still in control. Slide 26

Question 45

What details do you need to know for each muscle?

Answer 45

Name, attachments, main actions, nerve supply and how to clinically test it. Slide 27