Shoulder Instability

Question 1

Definition for what?

Anterior, posterior, inferior or multidirectional glenohumeral laxity due to traumatic or atraumatic pathology

Answer 1

Instability

Question 2

Definition for what?

humeral head partially slips out of socket with spontaneous reduction

Answer 2

Subluxation

Question 3

Definition for what?

humeral completely slips out of glenoid fossa with spontaneous reduction or sometimes requiring manual manipulation

Answer 3

Dislocation

Question 4

Two specific instability patterns have been described:

(a) _________ with a Bankart lesion that can be successfully treated with surgery
(b) ____________ that is commonly bilateral and is often successfully treated with rehabilitation and occasionally an inferior capsular shift (surgery)

Answer 4

a) TUBS - Traumatic unilateral dislocation

b) AMBRI - Atraumatic multidirectional instability

Question 5

________________________can create disruption in the dynamic stabilization of the glenohumeral joint resulting in instability, subluxations and or dislocations

Answer 5

Laxity, trauma or overuse

Question 6

Dx/Tx
Clinical Symptoms
(1) Patient with anterior instability will describe the sensation of the shoulder slipping
out of joint when arm is abducted and externally rotated
(2) Initial anterior dislocation is associated with trauma from a fall or forceful throwing motion
(3) Recurrent dislocations may occur simply by positioning arm overhead
(4) Patient with posterior dislocation will describe a force that is posteriorly directed
(5) Patient with multidirectional instability may have vague symptoms but usually related to activity
-(a) Ability to voluntarily dislocate shoulder is frequently associated with multidirectional instability and has a poor prognosis for surgical treatment
Physical Exam
(1) Visual
-(a) Joint disfigurement noted if arm is currently dislocated
-(b) Anterior dislocation- most common direction
—1) Patient supports arm in neutral position
-(c) Posterior dislocation- patient holds arm in adduction and internal rotation
(2) Palpation
-(a) General tenderness noted throughout shoulder
(3) ROM
-(a) Limited to no AROM or PROM if currently dislocated
-(b) Multidirectional instability will not limit ROM but humeral “clucking” is noted with flexion and abduction/adduction
-(c) If multidirectional instability is suspected patient should be checked for generalized ligamentous laxity
(4) Muscle Tests
-(a) Typically limited by pain or lack of joint motion
(5) Neurovascular Tests
-(a) Assess axillary, musculocutaneous, median, ulnar and radial nerve function
-(b) Assess radial pulse and capillary refill
(6) Special Tests
-(a) Positive Sulcus test with inferior laxity
-(b) Positive Apprehension test with anterior instability
-(c) Anterior/Posterior Drawer test - anterior/posterior laxity
-(d) Jerk test- posterior instability

Answer 6

Shoulder Instability
Treatment
(1) Reduce acute dislocations
-(a) Stimson technique- gravity assisted with patient lying on stomach
-(b) Longitudinal traction- elbow at 90 degrees flexion while longitudinal
traction is applied to the humerus. Gently rotate arm.
-(c) Valium maybe be required to relax muscle structures to allow for reduction
-(d) Re-evaluate axillary nerve function after reduction
(2) Immobilize arm in a sling in neutral rotation
(3) Light duty to include no active use of arm for 2-3 weeks
(4) Begin rotator cuff strengthening 2-3 weeks post reduction
(5) Physical therapy consult
(6) Orthopedic consult

Question 7

Referral Decisions/Red Flags

First time dislocations or evidence of neurovascular compromise require orthopedic evaluation for possible surgery

Answer 7

MEDEVAC

Question 8

Diagnostic Test

(1) ______ to include AP and axillary views- Rule out Hill-Sachs lesion with anterior dislocations
(2) ______ radiographs needed if posterior dislocation is suspected
(3) _____- needed to evaluate health or rotator cuff tendons, labrum (Bankart lesion) and other soft tissue structures

Answer 8

1) Radiographs
2) AP and axillary
3) MRI