Movements

Question 1

Movements allowed by ac joint

Answer 1

small glides of acromion on clavicle

Question 2

movements at sc joint

Answer 2

small glides to accommodate movement of scapula

• protraction: clavicle moves backwards at sc
• retraction: forwards at sc
• elevation: downwards at sc
• depression: upwards at sc
• rotation - clavicle rotates along axis

Question 3

Movements of scapula on thorax

Answer 3

> retraction: ‘bracing’ - pulling scapulae posteriorly around thorax
protraction: ‘rounding’ - pushing scapulae anteriorly around thorax
elevation: scapulae move superiorly
depression: scapulae move inferiorly
lateral rotation: arm above head - inferior angle moves laterally (away from spine0
medial rotation: arm back to side - inferior angle moves medially (towards spine)

Question 4

Elevation

Answer 4

Range: ~10cm upwards
limited by: costoclavicular ligament 
                 : tension in serratus anterior + pec minor
Muscles: upper fibres of trapezius
              : levator scapulae

Question 5

Depression

Answer 5

Range: ~ 2 cm downwards
limited by: interclavicular ligament
                 : intra-articular disc
Muscles: serratus anterior
              : pec minor
              : lower fibres of trapezius
\+gravity

Question 6

Protraction

Answer 6

Range: 5 cm anteriorly 
limited by: anterior sc ligament
                 : costoclavicular ligament
muscles: serratus anterior 
              : pec minor

Question 7

Retraction

Answer 7

Range: 2cm from neutral
limited by: posterior sc ligament
                 : costoclavicular ligament
mucles: rhomboids
            : middle trapezius

Question 8

medial rotation

Answer 8

limited by: interclavicular ligament
                : sternoclavicular ligaments (ant+post)
Muscles: rhomboids
              : levator scapulae
              : pectoralis minor

Question 9

lateral rotation

Answer 9

limited by: conoid ligament
muscles: upper + lower trap fibres
: serratus anterior