Dislocations

Question 1

What is the difference between a dislocation and a sublaxation?

Answer 1

Dislocation refers to the complete dissociation of articulating joint surfaces whilst sublaxations occur when the articulating surfaces are partially in contact

Question 2

How does a dislocation occur?

Answer 2

Joint stability depends on the interaction between passive, active and neural subsystems. When the force applied to a joint exceeds capabilities of active subsystems (or when compromised) loads are transferred to passive subsystem. Excessive load placed on passive subsystem causes a joint to abnormally translate or luxate

Question 3

Compare dislocations of major joints (shoulder and hip)

Answer 3

Shoulder dislocations are more common and 95% occur anteriorly (i.e., throwing action). Hip dislocations are rare due to stability of hip joint and generally occur posteriorly (90%)

Question 4

What are the mechanisms of sternoclavicular joint injury?

Answer 4

Anterior dislocations are more common

Question 5

What is pubic symphysis diastasis?

Answer 5

A dislocation of the pubic fibrocartilaginous joint occurring as a result of forceful impacts (i.e., horse riders landing on saddle with high vertical force). Causes damage to stabilizing ligaments