Shoulder Dislocation Flashcards
Most common sequelae of anterior shoulder dislocations
Bankart lesions
What are Bankart lesions
detachment of the antero-inferior labrum from the glenoid rim, accompanied by detachment of the inferior glenohumeral ligament from its glenoid origin.
Described as a bony when the glenoid rim itself fractures in lieu of a labral detachment.
What is a Hill-Sachs lesion
osteochondral depression in the posterior humeral head caused by impaction of the head on the anterior glenoid during anterior dislocation. If severe, may contribute to recurrent instability.
Most common type? Anterior or posterior? Why?
Dislocations in the anterior direction are by far the most frequently occurring, representing up to 90% of all shoulder dislocations. Posterior dislocations are significantly less common and may be more insidious in presentation.
Inferior dislocations are aka?
Luxatio erecta
occurs when the arm is forced into a frozen hyperabducted state—sometimes referred to as the “Superman” position because of its likeness to the superhero’s famous flight stance. With the humeral head forced inferiorly, deltoid and other muscular attachments pull the arm into extreme abduction. Neurovascular compromise almost always accompanies this type of dislocation.
Static stabilizers of shoulder
passively support the humeral head in the glenoid
Shoulder dynamic stabilizers
rotator muscles and periscapular musculature.
Most important static stabilizer of shoulder
glenohumeral ligaments, particularly the anterior band of the inferior glenohumeral ligament.
Typical injury
involves one falling on a shoulder that is in extension, external rotation, and abduction
Tests for anterior instability
apprehension test
patient is placed in the supine position and asked to place their arm in a comfortable position. The arm is then gradually externally rotated and abducted by the examiner
Relocation test
performed concurrently with a positive apprehension test: When the patient begins to exhibit guarding, a posteriorly applied force should relieve the sensation of impending dislocation.
Test to asses anterior and posterior instability
load and shift test
examiner applies an axial load on the elbow to drive the humeral head into the glenoid fossa and simultaneously applies an anterior and posterior force on the humeral head with the remaining hand. Translation of the humeral head 0 to 1 cm in either direction is considered mild, whereas translation of greater than 2 cm or translation beyond the glenoid rim is considered severe
Recommended xray view
Velpeau axillary radiograph
patient leans backward over an x-ray cassette and angling the caudally directed beam downward from above the shoulder.
Pathognomonic radio graphic finding for anterior glenohumeral dislocation
Hill-Sachs lesion
Xray view to see Hill-Sachs lesion
Stryker notch
patient places the palm of the hand of the affected extremity on the crown of the head and beam is directed toward the coracoid process.
Management (non operative)
Stimson technique
attaching weights to the affected extremity with the patient in the prone position. The gentle traction overcomes muscular spasm over a period of time and allows for reduction to occur.
Hippocratic maneuver and traction-countertraction techniques
achieve reduction by combining traction with internal and external rotation movements. The most significant difference between these techniques is the method of countertraction: In the Hippocratic maneuver, the practitioner places his or her foot in the patient’s axilla to stabilize the body while he or she is pulling the affected arm. In the traction-countertraction method, an assistant provides countertraction by pulling on a sheet wrapped around the patient’s body from under the axilla.
