shoulder dislocations Flashcards
also known as
glen-humeral dislocationa
classified as either
traumatic or atraumatic
traumatic shoulder dislocations
anterior shoulder dislocations are much more common accounting for 95% of cases while posterior dislocations only account for around 5%
why do traumatic anterior shoulder dislocations occur
due to an excessive external rotatory force or falling onto the back of shoulder
what do anterior shoulder dislocations often cause
detachment of the anterior glenoid labrum resulting in a bankart lesion
what else can anterior shoulder dislocations also cause
the posterior humeral head to impact on the anterior glenoid which causes and importation fracture of the posterior humeral head called a hill-sachs lesion
what is a bankart lesion
anterior shoulder dislocation which results in the detachment of the anterior glenoid labrum
what is a hill-sacks lesion
fracture of the posterior humeral head due to importation of the posterior humeral head on the anterior glenoid
what can anterior shoulder dislocations damage
the axillary nerve as it can be stretched as it passes through the quadrangular space
what other structures can be damaged in anterior shoulder dislocations
sometimes can even compress other nerves of the brachial plexus and/or the axillary artery
presentation of anterior shoulder dislocation
- loss of symmetry
- loss of roundness of the shoulder
- arm held in adducted position supported by patients unaffected arm
what is the principal sign of damage to the axillary nerve
loss of sensation in the regimental badge area
what has to be done before and after x-rays so you don’t get sued
neurovascular assessment must be carried out and documented in the notes
what is more rare but can occur in anterior shoulder dislocations
fractures of the surgical neck and greater tuberosity of the humerus
diagnosis of shoulder dislocations
x-rays
management of anterior shoulder dislocations
- closed reduction under sedation or anaesthesia
- neurovascular assessment before and after this procedure
- redo x-rays to confirm reduction
- patient is placed in a sling for 2-3 weeks allowing the capsule to heal and then physiotherapy is commence
who sometimes presents with delayed anterior shoulder dislocations
alcoholics
whats the issue in delayed presentations of anterior shoulder dislocations
it may be impossible to reduce shoulder using closed reduction so they may need open reduction
when would an anterior shoulder dislocation need surgery
- fractures of the greater tuberosity usually resolve with closed reduction but if not then requires an open reduction internal fixation procedure (ORIF)
- fractures of the surgical neck of the humerus nearly always require surgery
what is the risk of recurrent dislocation predicted by
the age of the patient at the time of initial dislocation
risk of recurrent dislocation in patients under 20
80%
risk of recurrent dislocation in patients over 30
20% and this further reduces with age
management of recurrent dislocations
bankart repair which involves re-attaching the torn labrum and capsule
posterior shoulder dislocations cause
caused by a posterior force on an adducted and internally rotated shoulder, more common in people who have seizures or have been electrocuted
in whom may bilateral shoulder dislocations occur
epileptics who have had a seizure
how common are posterior shoulder dislocations
much less common than anterior shoulder dislocations and only account for 5% of shoulder dislocations
clinically you can… in posterior shoulder dislocations
the humeral head can be palpated posteriorly
whats the issue with posterior shoulder dislocations
often misdiagnosed on x-rays as its much less obvious than anterior shoulder dislocations
classical x-ray sign in posterior shoulder dislocations
light bulb sign there the excessively internally rotated humeral head looks symmetrical like a light bulb on AP view
management of posterior shoulder dislocations
is the same as for anterior shoulder dislocations
- x-ray
- closed fixation
- sling for 2-3 weeks
- physiotherapy
atraumatic shoulder dislocations
occur in patients with marked ligamentous laxity (familial ligamentous laxity) or due to connective tissue disorder (marfans and ehlers danlos syndrome)
what to atraumatic shoulder dislocations tend to be
multi-directional which may or may not be painful
what is management of atraumatic shoulder dislocations
physiotherapy to strengthen the rotator cuff muscles
in posterior shoulder dislocations what extra x-ray view should you obtain
oblique view