Bone Dislocations

A dislocation involves complete loss of congruity between articular surfaces whereas a subluxation implies movement of the bones of the joint, but with some parts of the articular surface still in contact. Describe dislocations in terms of the displacement of the distal bone. For example, the most common shoulder dislocation is described as ' anterior, with the humeral head lying in front of the glenoid. Am to reduce dislocations as soon as possible in order to prevent neurovascular complications, d risk of reoccurrence and d pain. However, in general, aim to x-ray (to identify the exact dislocation ± associated fracture) before attempting a reduction.

Exceptions to this principle are

• Dislocations associated with considerable neurovascular compromise requiring urgent intervention (this includes some ankle fracture dislocations)
• Uncomplicated patellar dislocations
• Uncomplicated mandibular dislocations
• Some patients with (very) recurrent shoulder dislocations, where there may be longer - term concerns regarding radiation exposure
• Some patients with collagen disorders resulting in hypermobility ( e.g. Ehlers - Danlos syndrome ) and unusual / recurrent dislocations without significant trauma
• Pulled elbow ' in young children

APPROACH TO BONE DISLOCATIONS

Use analgesia / sedation / anesthesia appropriate to the dislocation and the individual circumstances. For example, patellar dislocations often reduce under Entonox, finger proximal interphalangeal joint (PIPJ) dislocations with LA digital nerve blocks, shoulder dislocations with IV analgesia dation, whereas posterior hip dislocations typically require manipulation under GA. Except in very exceptional circumstances, X - ray after manipulation to confirm adequate reduction and also to check for fractures which may not have been apparent on initial X – rays.