L35 - Functional Anatomy for ExRx Part 2

• Muscle fibre direction matters!

  • Most muscles oriented mainly in same direction (from origin to insertion) = parallel
  • Where for more important (eg rectus femoris) got bipennate
  • Go in 2 directions
  • Muscle fibres are therefore shorter
  • More muscle fibres therefore can produce more force
• Movements:

  • Movements mostly work with for ExRx as occur where large muscle groups are:
  • Flexion/Extension
  • Abduction/Adduction
  • Medial/Lateral Rotation
• The shoulder:

  • Wide ROM
  • Muscles involved with shoulder joint
  • Deltoid
  • Pectoralis major
  • Lattissimus dorsi
• Deltoid:

  • Abductor of the arm at the shoulder joint
  • Anterior: flexor & medial rotator of the humerus
  • Posterior: extensor & lateral rotator
• Pectoralis major

  • Adductor of the shoulder
  • Medial rotator of the shoulder
  • Assist with deep breathing
  • When humerus is fixed - helps expand chest, enlarging cavity for lungs
  • Triangular muscle, base vertical midline of sternum (5-6 rib), to anterior of humerus
  • Upper most fibres (from clavicle)
  • Lower most fibres (from thorax/midline)
  • Insertion on anterior part of humerus
  • Also internal medial rotation
  • Draws arm across the body (eg throwing ball, moving something from one side to another)
• Latissimus dorsi:

  • Extension
  • Adduction
  • esp when hands above head
  • Like pulling a blind (up → down to body)
  • Medial rotation
  • Moving arm around to back
  • Like when tying up dress at back
  • Attaches to posterior part of humerus so also shoulder muscle (origin of lower back & thorax, wraps around trunk & diverges to posterior part of humerus)
• Rectus abdominis:

  • Flexion of the trunk
  • From 5/6th rips and xiphoid process (bottom of sternum) to base of pelvis/pubis
  • Muscle fibres interrupted at 3 intervals, transverse bends of very fibrous tissue (tenuous intersections)
  • eg when getting up from bed
  • When body in air, rectus abdominis also supports front of pelvis (to stay one nice line)
  • Functional exercise = running & jumping exercises
• Functional activities of the shoulder joint:

  • Reach up to a high shelf → reaching up exercises
  • Push open a door → pushing exercises
  • Reach behind → reaching behind exercises
  • Turn over a page of a newspaper on a table → turning of the arm exercises
  • Can be done with a weight to mimic this
  • Pull open a drawer → pulling exercises
• Functional activities of the abs:

  • Sitting up from lying
  • Lifting the head from lying
  • Sitting up from lying while turning the trunk (involves cross abs)
• Functional Exercises:

  • Functional activities difficult
  • Functional training means multiple joints, multiple muscles, multiple planes
  • When a client needs to functionally train (can be a similar movement mimicking it)
  • Functional movement = mimic specific thing client needs to practise
  • eg squats mimic sitting down & standing up from a chair
• The elbow:

  • Hinge joint
  • Muscles involved are:
  • Biceps brachii
  • Triceps brachii
• Biceps brachii:

  • Flexion of the elbow
  • Concentrically flex elbow
  • Eccentrically controls lowering of forearm (to stop overextension)
  • works with triceps
  • Supinator of the forearm
  • Using flexion & supination = opening a door knob or screwing with a screwdriver
  • No attachment to humerus
  • 2 tendons originate at scapular & inserts at medial shaft of radius (just below elbow)
• Tricep brachii:

  • Extensor of the elbow
  • All involve medial head
  • Other 2 heads only added when acting against resistance
  • eg extend arm while pushing above, or pushing up form a chair (eg tricep dips) → pectoralis major also used
  • Adduct the arm
  • Inferior of glenoid cavity, shaft of humerus, insert of ulna (via 1 tendon)
• Functional shoulder/arm exercises:

  • Reaching forwards
  • Protraction of the scapula: serratus anterior, pectoralis major
  • Flexion of the shoulder: deltoid (anterior fibres), pectoralis major (clavicular fibres), coracobrachialis
  • Extension of the elbow: triceps
• Functional shoulder/arm exercises:

  • Pulling back towards the body
  • Retraction of the scapula: rhomboids, trapezius (middle fibres)
  • Extension of the shoulder joint: deltoid (posterior fibres), latissimus dorsi
  • Flexion of the elbow: biceps brachii, brachialis
• Functional shoulder/arm exercises:

  • Reaching across the body
  • Protraction of the scapula: serratus anterior, pectoralis major
  • Flexion, abduction & medial rotation: deltoid (anterior fibres), pectoralis major, subscapularis
  • Extension of the elbow: triceps
• Functional shoulder/arm exercises:

  • Reaching behind the body
  • Retraction of the scapula: rhomboids, trapezius (middle fibres)
  • Extension & lateral rotation: deltoid (posterior fibres), infraspinatus, teres minor
  • Extension of the elbow: triceps
• Functional shoulder/arm exercises:

  • Lifting the trunk of the arms
  • Depression of the scapula: trapezius (lower fibres), pectoralis minor
  • Extension & adduction: latissimus dorsi, teres minor
  • Extension of the elbow: triceps
• The hip:

  • Has ROM but less than shoulder, as is a more stable joint
  • Long muscles that cross over 2 joints can only work efficiently across 1 joint at a time (eg hamstrings & rectus femoris)
  • Hamstrings: can only extend hips heaps when knee in flexion (such as during running)
  • Abductors & adductors important for gait
• Gluteus maximus:

  • Extension of the hip
  • esp after hip been flexed
  • Such as squats
  • eg stepping stool or running
  • 1 of the largest muscles in the body
  • Used from sitting to standing, or going up stairs
  • Origin from posterior corner of iliac crest & inserts laterally over posterior part of hip joint & attaches to femur
  • Iliotibial (IT) band if lose muscle mass really bad hanging on IT band
• Functional hip exercises:

  • Transfer of body from lying to sitting
  • Transfer of the body from sitting to standing
  • Flexion: leg swing in walking & lifting the foot on to the step above in climbing stairs
  • Extension: raises the body from sitting to standing & up on to the step above in climbing stairs
  • Propulsion (exerting forces on the ground to propel the body) such as in walking, jumping or climbing stairs
• The knee:

  • Involves patella which is important for allowing quads to have more force by having a longer arm/leverage
  • Muscles involved
  • Quadriceps femoris
  • Hamstrings
  • Triceps surae
  • gastrocnemius (for knee)
  • soleus (not involved in knee)
• Quadriceps femoris:

  • Extensor of the knee
  • Involves 4 muscles on anterior side of thigh
  • Most superficial in midline
  • Vastus medialis, vastus intermedius (deep under rectus femoris), vastus lateralis
  • Rectus femoris only one that crosses hip joint (involved in hip flexion)
  • Rest origin from femur & all attach to tibia
  • Important for stability of knee joint
• Hamstrings:

  • Flexor of the knee
  • Lift foot off the floor
  • Biceps femoris (short head on femur), semitendinosus, & semimembranosus (rest attach to hip) attach to medial side of tibia except biceps femoris to fibula
• Calf muscle = Triceps surae:

  • Plantar flexion of the ankle
  • Raises heel off from ground
  • Flexion of the knee (gastrocnemius only)
  • Involves gastrocnemius (posterior of femur one above each condyle) crosses knee joint so used in flexion of knee
  • Soleus origin below knee
  • Both match up to form one of the strongest tendons in body (Achilles tendon)
  • Attaches to posterior calcaneus
• Functional leg exercises:

  • The knee flexes when the leg is lifted up to the next step in climbing stair, & when sitting in a crouched position or cross legged
  • Sitting & standing up (squat)
  • Push off when walking (calf raises)
  • Spring & lift (calf muscles)
  • Walking, running & jumping