Dislocations Flashcards
Difference between dislocation and subluxation
Dislocation = complete joint disruption
Subluxation = partial dislocation (not fully out of joint)
Diagnosis of dislocations
Examination
Radiological diagnosis
deformity in anterior shoulder dislocation
Squared off shoulder
Locked in internal rotation
Mechanism of anterior shoulder dislocation
Fall on arm or shoulder
Forced abduction, external rotation and extension of arm
Blow to posterior shoulder
Appearance of posterior shoulder dislocation on x-ray
light-bulb appearance of humeral head
Mechanism of posterior shoulder dislocation
Rarer than anterior Humeral head forced posterior in adduction, internal rotation and flexion of arm 3E's = epilepsy, EtOH, electrocution Blow to anterior shoulder Imbalance in rotator cuff muscles
What does a posterior elbow dislocation look like on x-ray
olecranon prominent
Mechanism of posterior elbow dislocation
Fall onto extended arm with either hyperextension or posterolateral rotatory mechanism
Complications of posterior elbow dislocation
Stiffness
Instability
Ectopic ossification
Radio-ulnar joint disruption
what does a posterior hip dislocation look like on x-ray
femur head outside the acetabulum
Clinical picture of posterior hip dislocation
Leg short, flexed, internal rotation, adduction
Mechanism of posterior hip dislocation
Common in trauma due to large force required - i.e. MVA - hip flexed and knee pushed back by dashboard
complications of posterior hip dislocation
Sciatic nerve lacerated, stretched or compressed
Clinical picture of anteroposterior knee dislocation
loss of normal contour, extended
what are knee dislocations associated with
Ligamentous injuries - bicruciate (anterior and posterior cruciate ligaments) tears
