Shoulder dislocation occurs commonly in which direction?
Ref: Apt ex's System of Orthopaedics and Fractures, 8th ed.Explanation:Shoulder DislocationA dislocated shoulder occurs when the humerus separates from the scapula at the glenohumeral joint.The shoulder joint has the greatest range of motion of any joint in the body and as a result is particularly susceptible to dislocation and subluxation.Approximately half of major joint dislocations seen in emergency departments are of the shoulder.Partial dislocation of the shoulder is referred to as subluxation.ClassificationAnterior (forward)Over 95% of shoulder dislocation cases are anterior.Most anterior dislocations are sub-coracoid.Sub-glenoid, subclavicular, and. very rarely, intrathoraeic or retroperitoneal dislocations may occurAnterior dislocations are usually caused by a direct blow to or fall on an outstretched arm.The patient typically appears holding their arm externally rotated and slightly abducted.It can result in damage to the axillary artery and axillary nerve (C5, C6).Damage to the axillary nerve results in a weakened or paralysed deltoid muscle.As the deltoid atrophies unilaterally, the normal rounded contour of the shoulder is lost. A patient w ith injun to the axillary nerv e will have difficulty in abducting the arm from approximately 15deg away from the body.The supraspinatus muscle (supplied by suprascapular nerve) initiates abduction from a fully adducted position (the first 15 degrees).Posterior (backward)Posterior dislocations are occasionally due to electric shock or seizureCaused by strength imbalance of the rotator cuff muscles.Patients typically present holding their arm internally rotated and adducted, and exhibiting flattening of the anterior shoulder and a prominent coracoid process.Often goes unnoticed, especially elderly & unconscious trauma patient.Inferior (downward) (luxatio erecta)Inferior dislocation is the least likely form, occurring in less than 1% of all shoulder dislocation cases.This condition is also called luxatio erecta because the arm appears to be permanently held upward or behind the headIt is caused by a hyper abduction of the arm that forces the humeral head against the acromion. High incidence of vascular, neurological, tendon, and ligament injuries.
Anteriorly
Superiorly
Postriorly
Medially
Dislocation of Shoulder