Types of shoulder Dislocation: Shoulder dislocation 1. Anterior 2. Posterior 3. Luxatio erecta (inferior dislocation)
Anterior Dislocation: head is dislocated anterior to the glenoid Most common among all dislocations of shoulder Mostly traumatic MOI: happens in hyperabduction and external rotation Posterior dislocation: head is dislocated posterior to glenoid Most frequent cause is epilepsy, electric shock, electroconvulsive therapy MOI: flexion, adduction and internal rotation Luxatio erecta: head is quite inferior to the glenoid Occurs due to holding an object while vertical fall Shoulder in hyperabduction at the time of presentation Recurrent dislocation: It could be in any direction: ant/post/inferior Acute anterior dislocation Mechanism of injury: 1. Direct contact 2. Anteriorly directed force in an abducted and externally rotated shoulder Clinical features: 1. Pain, swelling over shoulder 2. Inability to use arm 3. Arm held in slight abduction and external rotation Specific signs in a DISLOCATED shoulder A: Axillary concavity reduced B: Bryant s test: anterior axillary fold is at lower level when compared to normal side C: Callaway s test: Increased anteroposterior diameter of axilla C: Contour of shoulder lost due to flattening
D: Duga s test: inability to touch opposite shoulder H: Hamilton ruler test: a ruler placed on lateral aspect of arm touches the acromion. (it fails to touch on normal side) H: Hollow posterior aspect I: Increased length of arm compared to normal side. R: Regimental badge sign: loss/decrease in sensation over axillary nerve distribution area over upper lateral aspect of arm Essential pathological lesion in a traumatic anterior dislocation of shoulder is 1. Bankart lesion: detachment of anteroinferior labrum with capsule 2. Hill Sach s lesion on posterolateral aspect of head of humerus Diagnosis: 1. Plain xray of shoulder: AP and axillary view 2. MRI to detect Bankart and hill sach s lesion Treatment of acute anterior dislocation: Reduction of dislocation in sedation/ga Various manoeuvres for reduction 1. Kocher s method: traction-counter traction method 2. Hippocratic method: Leg in axilla method 3. Stimson s method: Gravity method
Kocher s method: Quite popular Uses traction-counter traction method with following sequence TEAI: traction-countertraction----external rotation---adduction---internal rotation Can led to fracture of humerus due to rotational stress Hippocratic method: The examiner pushes his leg into the axilla (countertraction) of patient and pulls arm towards himself (traction). Now almost obsolete Stimson s method: Used in patients who present with old unreduced anterior dislocation of shoulder between 3-6 weeks Patients is asked to lie prone on the couch and weight is applied over his forearm which acts like traction. Edge of bed is like counter traction Complications of shoulder dislocations 1. Associated fracture of greater/lesser tuberosity/shaft/neck of humerus 2. Axillary nerve palsy 3. Rotator cuff tear in elderly patients 4. Recurrent dislocation
Recurrent Anterior dislocation Recurrent anterior dislocation is not uncommon C/F: 1. Apprehension test 2. Relocation-release test Investigation: 1. MRI of shoulder 2. CT scan to assess the glenoid bone loss and Hill sachs size Treatment of recurrent anterior dislocation 1. Arthroscopic / open Bankart repair: the torn anteroinferior labrum is resutured onto the glenoid margin arthroscopically 2. Latarjet Procedure: The tip of coracoid (2cm) is taken off from coracoid along with the attachment of coracobrachialis and short head of biceps and is fixed onto the anterior glenoid margins with two screws. It is performed when the anteroposterior diameter of glenoid is eroded more than 21%
Procedures of historical importance 1. Puttiplatt procedure Double breasting of subscapularis It prevents dislocation by limiting ER of shoulder 2. Bristow s procedure: Similar to Latarjet. Here tip of coracoid is fixed with single screw over glenoid margin. Latarjet is preferred over Bristows. Recent advances: Remplissage is performed for large hill sachs lesions. It is a procedure wherein the tendon of Infraspinatus is sutured over the large Hill sachs defect to prevent engagement of Hill sachs lesion with glenoid margin.