Muscles & MovementMuscles & MovementMovement Studies 2009/10

MS 2009/10

Learning OutcomesLearning OutcomesDescribe the different types of muscle

attachment

Explain how muscles can contribute to movement and stability

Perform movement analyses in terms of:

◦ the functional relationship of relevant muscles

◦ the type of muscle contraction◦ the ‘range’ a muscle is working in/through

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MusclesMusclesWhat do we need

muscles for?

Think of 3 roles muscles have in the body

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Skeletal MuscleSkeletal MuscleAre all skeletal muscles the same

shape?

How does the structure of skeletal muscle relate to its function?

Palpate the following muscles on yourselves and try and determine what they feel like

Are they the same shape/thickness?MS 2009/10

a c

b d

e

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Muscular AttachmentsMuscular Attachments

Going back to our muscle examples what do you think they attach to?

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Muscular AttachmentsMuscular Attachments 1. Tendons

E.g. Achilles tendon

E.g. Biceps tendon

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Muscular AttachmentsMuscular Attachments

II. Aponeuroses

Sheets of collagen- connective tissue providing muscular attachment

E.g. External Oblique

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Muscular AttachmentsMuscular Attachments

III. Deep Fascia

Compact collagen

fibresMore uniform

direction

E.g Tensor fascia latae

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Muscle attachmentsMuscle attachmentsIV. Fleshy

Muscle directly into bone

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Muscle ActionMuscle ActionFor each of the

joints listed name the key muscle groups which perform the movements at that joint with their approximate location and an example

E.g. the hip flexors are located on the anterior surface of the hip joint and thigh and include iliopsoas

Hip

Knee

Ankle

Shoulder

Elbow

Wrist

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Hip◦ Flexors, extensors,

abductors, adductors,rotators

Knee◦ Flexors, extensors

Ankle◦ Dorsiflexors,

plantarflexors, invertors, evertors

Shoulder◦ Flexors, extensors,

abductors, adductors, rotators

Elbow◦ Flexors, extensors

Wrist◦ Flexors, extensors,

deviators

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Muscle ActivityMuscle Activity

What happens to a muscle when it is activated?

Shortens?

Lengthens?

Stays the same?

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ConcentricConcentricMuscle tension

exceeds resistance and it shortens the muscle

Speed of muscle fibre shortening depends on resistance

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EccentricEccentricMuscle tension is

less than the resistance causing the muscle to lengthen whilst working

Tension developed is less than the resistance

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IsometricIsometricMuscle does not

change in length

Tension produced never exceeds resistance

Which muscle group is working hardest in this example?

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Muscle ContractionMuscle ContractionWhy are there different types of

muscle contraction?

Straighten your leg while sitting: Which muscles are working?

◦ What sort of muscle work is occurring in the quadriceps and hamstrings?

◦ Where might isometric muscle contraction be happening?

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Analysis of MovementAnalysis of Movement

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Look at each other walking:Analyse the movement in terms of:

◦ Identifying the main muscles working at the hip and knee during gait

◦ Identifying the type of contraction in each muscle group i.e. concentric, eccentric, or isometric

Muscle FunctionMuscle FunctionAs you raise your

leg to place your foot on a step several different muscles are working

Are they all functioning in the same way?

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Group Action of MusclesGroup Action of MusclesMuscles work in groups not singly

A number of muscles are active during any movement

It is this group action which results in co-ordinated movement

Muscles can be divided by function into prime movers/agonists, antagonists or fixators

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Functional muscle groupsFunctional muscle groupsPrime

mover/agonistA muscle or muscle

group which contracts to bring about movement

AntagonistsA muscle or muscle

group which opposes the prime mover and relaxes and lengthens progressively to control movement

FixatorsMuscles which

work to steady the origin of the prime mover

SynergistsSpecial form of

fixator

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Muscle RangeMuscle Range

MS 2009/10‘Musculoskeletal Assessment’ Clarkson

Ranges of biceps muscle Ranges of biceps muscle workworkHold arm out straight and then

move hand to shoulder?

Where in range is your biceps muscle?

Take your arm back out to 90º now where in range are your biceps?

Now straighten fully – where in range are your biceps

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Ranges of iliopsoas* muscle Ranges of iliopsoas* muscle workwork• Iliacus and psoas major work

together functionally iliopsoas

Sit on a plinth—where in range is your iliopsoas?

Lean forwards—where in range is your iliopsoas?

Stand up and straighten fully—where in range is your iliopsoas?

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IMPORTANCE OF MUSCLE IMPORTANCE OF MUSCLE RANGERANGEWhy is it important to know

where in range a muscle is working?

Inner range – often weak

Middle range – often used for muscle testing

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TasksTasksThere are four tasks for you to

work through

Divide into 5 groups

Use the texts available

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Task 1Task 1Sit down from standing

Which lower limb muscle group is predominant in producing this movement?

How would you describe the type of muscle contraction in this muscle group?

What is the function of this muscle group?

In which range is the muscle group contracting at the start of the movement?

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Task 2Task 2Stand on your left leg and flex your

right knee

Which muscle group produces knee flexion?

Which muscle group is working as an antagonist?

What type of muscle contraction describes the right iliopsoas activity?

How would you classify the iliopsoas function in this case?

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Task 3Task 3In standing raise your right foot on

to a small step.

In which range are the quadriceps working the knee?

In which range are the hamstrings working at the knee?

Where in range do the quadriceps exert the greatest force?

Which muscles are working as stabilisers?

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Task 4Task 4

During a normal gait cycle look at dorsiflexion of the ankle

Where in range do the dorsiflexors contract concentrically?

Classify the type/s of contraction and function of the dorsiflexors that occur during the cycle?

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Muscle AssessmentMuscle AssessmentPhysios assess

muscles for strength, length and control –these skills will be taught in NMS1

One means of grading muscle power is the Oxford or MRC grading scale

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Oxford/MRC grading scaleOxford/MRC grading scaleGrade Muscle Activity

0 No contraction

1 Flicker/trace contraction

2 Active movement with gravity eliminated

3 Active movement against gravity

4 Active movement against gravity and resistance

5 Normal powerMS 2009/10

ConclusionConclusionMake sure you are happy that the

learning outcomes have been met

Familiarise yourself with the main muscles of the hip and knee and how their attachments vary – relate this to their function

Use your bones to determine where the muscles attach

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