What is the mechanism of injury for a shoulder dislocation?
Mechanism of injury — An anterior shoulder dislocation is usually caused by a blow to the abducted, externally rotated, and extended arm (eg, blocking a basketball shot). Less commonly, a blow to the posterior humerus or a fall on an outstretched arm may cause an anterior dislocation.
How does posterior shoulder dislocation occur?
Posterior shoulder dislocations usually result from forceful contractions of the internal rotators that occur during seizures and electrical shock. This mechanism can force the humeral head posteriorly, out of its normal alignment and behind the glenoid. Less commonly, posterior shoulder dislocations follow trauma.
Which mechanisms for shoulder dislocation are examples of indirect force?
Posterior Shoulder Dislocation There is an indirect force applied to the humerus that combines flexion, adduction, and internal rotation. This is usually the result of one falling on an out stretched hand (FOOSH injury), MVA, or seizures.
What is the mechanism of injury for a dislocation?
When the bones that make up a joint slide out of place, it can cause the tendons, ligaments, and muscles around the joint to tear. It may also sometimes cause bones to break. Your doctor may recommend surgery to repair these injuries. Some severely dislocated joints can damage nerves and blood vessels around the joint.
What is a posterior dislocation of the shoulder?
Posterior dislocations also known as Reverse Hill-Sachs lesion are those in which the humeral head has moved backward toward the shoulder blade and they attribute to 4% of all shoulder dislocations.
What was the mechanism of injury?
Mechanism of injury (MOI) is the force or forces that cause injury when applied to the human body. Forces have characteristics such as speed, size and direction.
What forms the posterior shoulder?
The scapula or shoulder blade is the bone that connects the clavicle to the humerus. The scapula forms the posterior of the shoulder girdle. It is a sturdy, flat, triangular bone. The scapula provides attachment to several groups of muscles.
Which direction does the shoulder usually dislocate?
The shoulder joint is the most frequently dislocated joint of the body. Because it moves in several directions, your shoulder can dislocate forward, backward or downward. The most common variety is a forward (anterior) dislocation.
What is recurrent dislocation of shoulder?
Recurrent dislocation implies having repeated dislocations of the shoulder. Patients with a tendency for recurrent (repeated) dislocation or subluxation are said to have an unstable shoulder or shoulder instability (unstable shoulder).
Where is the posterior shoulder?
Posterior shoulder instability, also known as posterior glenohumeral instability, is a condition in which the head of the humerus (upper arm bone) dislocates or subluxes posteriorly from the glenoid (socket portion of the shoulder) as a result of significant trauma.