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Obtaining a history of the mechanism of injury is helpful.
Avulsion fractures may accompany dislocations. The alignment of these fractures
is usually improved with the reduction of the dislocation. The same is true of vessel or
nerve impairment associated with a dislocation. When a major long bone fracture (e.g.,
femur or humerus) accompanies a dislocation in the same area, the dislocation may not
even be diagnosed in view of the more apparent major fracture. In these cases, splinting
of the fracture is the main concern. The dislocation, for all practical purposes, is a
secondary issue, and usually not amenable to reduction by ordinary means.
A. Shoulder: Anterior-inferior dislocations of the shoulder joint account for over 95% of
shoulder dislocations. The mechanism of injury is usually external rotation and
abduction. The problem is often recurrent and the patient can identify the dislocation
quite readily. The patient will usually stabilize the shoulder in the most comfortable
position, but cannot bring the involved extremity across the chest to a position of rest.
The upper arm is held away from the body in various positions and cannot be brought
into a sling-type position. This differentiates a dislocation from a fracture of the humerus,
in which the patient usually splints the upper arm against the chest wall for comfort.
Check circulation, motor and sensory function to the hand, and also sensory function
along the outer aspect of the shoulder (axillary nerve), and document findings.
Posterior dislocations of the shoulder are not common and tend to occur mainly
with electrical injuries or tonic-clonic seizures. In this instance, the upper arm and
forearm are held across the anterior chest wall and attempts at externally rotating the
upper arm away from the chest are restricted and painful. The diagnosis is often difficult
to make.
One method for reduction of an anterior shoulder dislocation is steady traction
with the arm abducted 90 degrees, pulling straight from the body with counter-traction
provided in the region of the axilla by an assistant. Muscle relaxation through massage
can enhance attempts at relocation and is appropriate. Be sure to pad the axilla and the
antecubital region to protect nerve and vascular structures during traction.
A second method is to place the patient prone and let the arm hang down toward
the ground with 10 to 15 pounds of weight secured to the hand. This method may be slow
and relaxation is critically important, but the muscles will generally fatigue in time, and
manual assistance by manipulation of the shoulder is helpful.
After reduction, immobilize the shoulder with sling and swathe.
B. Elbow: Look for obvious deformity when compared to the uninvolved side and
restricted flexion and extension of the joint. Most commonly, the olecranon dislocates
toward the rear and a bony prominence shows posteriorly.
Apply slow, steady traction to the forearm in a partially flexed position with
counter-traction applied to the upper arm by an assistant. The patient's ability to fully flex
the elbow is a sign of reduction. The joint may be displaced medially or laterally and may
require side pressure for realignment. After reduction, immobilize in a sling and swathe.
If reduction is not possible, splint in the position found.
C. Wrist: Wrist dislocations are very difficult to differentiate from a fracture, and often
difficult to reduce. Splint immobilization is the treatment of choice (see wrist fracture).