Shoulder Flashcards
Shoulder dislocation investigations
- anterior dislocation X-rays: AP, trans-scapular, axillary views
- posterior dislocation X-rays: AP, trans-scapular, axillary; or CT scan
What joints make up the shoulder
glenohumeral,
AC,
sternoclavicular (SC),
scapulothoracic
Anterior shoulder dislocation mechanism
Abducted arm is externally rotated/hyperextended, or blow to posterior shoulder
Involuntary, usually traumatic; voluntary, atraumatic
Anterior shoulder dislocation clinical features
Pain, arm slightly abducted and externally rotated with inability to internally rotate
“Squared off” shoulder
Positive apprehension test: patient looks apprehensive with gentle shoulder abduction and external rotation to 90º as humeral head is pushed anteriorly and recreates feeling of anterior dislocation
Positive relocation test: a posteriorly directed force applied during the apprehension test relieves apprehension since anterior subluxation is prevented
Positive sulcus sign: presence of subacromial indentation with distal traction on humerus indicates inferior shoulder instability
Axillary nerve: sensory patch over deltoid and deltoid contraction
Musculocutaneous nerve: sensory patch on lateral forearm and biceps contraction
Anterior shoulder dislocation radiographic findings
Axillary View -Humeral head is anterior
Trans-scapular ‘Y’ View -
Humeral head is anterior to the centre of the “Mercedes-Benz”sign
AP View - Sub coracoid lie of the humeral head is most common
Hill-Sachs and Bony Bankart Lesions -
± Hill-Sachs lesion: compression fracture of posterior humeral head due to forceful impaction of an anteriorly dislocated humeral head against the glenoid rim
± bony Bankart lesion: avulsion of the anterior glenoid labrum (with attached bone fragments) from the glenoid rim
Anterior shoulder dislocation treatment
Closed reduction with IV sedation and muscle relaxation
Traction-countertraction: assistant stabilizes torso with a folded sheet wrapped across the chest while the surgeon applies gentle steady traction
Stimson: while patient lies prone with arm hanging over table edge, hang a 5 lb weight on wrist for 15-20 min
Hippocratic method: place heel into patient’s axilla and apply traction to arm
Cunningham’s method: low risk, low pain; if not successful try above methods
Obtain post-reduction x-rays
Check post-reduction NVS
Sling x 3 wk (avoid abduction and external rotation), followed by shoulder rehabilitation (dynamic stabilizer strengthening)
Posterior shoulder dislocation mechanism
Adducted, internally rotated, flexed arm
FOOSH
3 Es (epileptic seizure, EtOH, electrocution)
Blow to anterior shoulder
Posterior shoulder dislocation clinical features
Pain, arm is held in adduction and internal rotation; external rotation is blocked
Anterior shoulder flattening, prominent coracoid, palpable mass posterior to shoulder
Positive posterior apprehension (“jerk”) test: with patient supine flex elbow 90° and adduct, internally rotate the arm while applying a posterior force to the shoulder; patient will “jerk” back with the sensation of subluxation
Note: the posterior apprehension test is used to test for recurrent posterior instability, NOT for acute injury
Full NV exam as per anterior shoulder dislocation
Posterior shoulder dislocation radiographic findings
Axillary view - Humeral head is posterior
Trans-scapular ‘Y’ View - Humeral head is posterior to centre of “Mercedes-Benz” sign
AP view - Partial vacancy of glenoid fossa (vacant glenoid sign) and >6 mm space between anterior glenoid rim and humeral head (positive rim sign), humeral head may resemble a lightbulb due to internal rotation (lightbulb sign)
± reverse Hill-Sachs lesion (75% of cases): divot in anterior humeral head
± reverse bony Bankart lesion: avulsion of the posterior glenoid labrum from the bony glenoid rim
Posterior shoulder dislocation treatment
Closed reduction with sedation and muscle relaxation
Inferior traction on a flexed elbow with pressure on the back of the humeral head
Obtain post-reduction x-rays
Check post reduction NVS
Sling in abduction and external rotation x 3 wk, followed by shoulder rehabilitation (dynamic stabilizer strengthening)
Shoulder disloccation prognosis
• recurrence rate depends on age of first dislocation
• <20 yr = 65-95%;
20 40 yr = 60-70%;
>40 yr = 2-4%
Shoulder dislocation specific complications
- rotator cuff or capsular or labral tear (Bankart/SLAP lesion), shoulder stiffness
- injury to axillary nerve/artery, brachial plexus
- recurrent/unreduced dislocation (most common complication)
Shoulder passive ROM
Abduction 180o
Adduction 45o
Flexion 180o
Extension 45o
Internal rotation - level of T4
External rotation 40-45o
Factors causing shoulder instability
- Shallow glenoid
- Loose capsule
- Ligamentous laxity
Frequency of dislocation types
- Anterior shoulder > Posterior shoulder
- Posterior hip > Anterior hip The glenohumeral joint is the most commonly dislocated joint in the body since stability is sacrificed for motion
Supraspinatus muscle attachments, nerve supply and function
Attachment
proximal - scapula
distal - greater tuberosity of humerus
Nerve supply - suprascapular nerve
Function - abduction
Infraspinatus muscle attachments, nerve supply and function
Attachment
proximal - scapula
distal - greater tuberosity of humerus
Nerve supply - suprascapular nerve
Function - external rotation
Teres minor muscle attachments, nerve supply and function
Attachment
proximal - scapula
distal - greater tuberosity of humerus
Nerve supply - axillary nerve
Function - external rotation
Subscapularis muscle attachments, nerve supply and function
Attachment
proximal - scapula
distal - lesser tuberosity of humerus
Nerve supply - subscapular nerve
Function - internal rotation and adduction
Spectrum of rotator cuff disease
Impingement
Tendonitis
Micro or macro tears
Rotator cuff disease etiology
• anything that leads to a narrow subacromial space
• most commonly, a relative imbalance of rotator cuff and larger shoulder muscles, allowing for superior translation and subsequent wear of the rotator cuff muscle tendons
■ glenohumeral muscle weakness leading to abnormal motion of humeral head
■ scapular muscle weakness leading to abnormal motion of acromion
• acromial abnormalities, such as congenital narrow space or osteophyte formation or Type III acromion morphology
- outlet/subacromial impingement: “painful arc syndrome”, compression of rotator cuff tendons (primarily supraspinatus) and subacromial bursa between the head of the humerus and the undersurface of acromion, AC joint, and CA ligament
- bursitis and tendonitis
- rotator cuff thinning and tear if left untreated
Rotator cuff disease clinical features
- insidious onset, but may present as an acute exacerbation of chronic disease, night pain, and difficulty sleeping on affected side
- pain worse with active motion (especially overhead); passive movement generally permitted
- weakness and loss of ROM, especially between 90°-130° (e.g. trouble with overhead activities)
- tenderness to palpation over greater tuberosity
• rule out
bicep tendinosis: Speed test;
SLAP lesion: O’Brien’s test
Rotator cuff disease investigations
- X-ray: AP view may show high riding humerus relative to glenoid, indicating large tear, evidence of chronic tendonitis
- MRI: coronal/sagittal, oblique and axial orientations are useful for assessing full/partial tears and tendinopathy ± arthrogram: geyser sign (injected dye leaks out of joint through rotator cuff tear)
- arthrogram: can assess full thickness tears, difficult to assess partial tears
Rotator cuff disease treatment
• non-operative
■ for mild (“wear”) or moderate (“tear”) cases
■ physiotherapy, NSAIDs ± steroid injection
• operative
■ indication: severe (“repair”)
■ impingement that is refractory to 2-3 mo physiotherapy and 1-2 corticosteroid injections
■ arthroscopic or open surgical repair (i.e acromioplasty, rotator cuff repair)
Screening out rotator cuff tears - questions for the bedside
- No night pan (SN 87.7%)
- No painful arc (SN 97.5%)
- No impingement signs (SN 97.2%)
- No weakness
Ruling in Rotator Cuff Tears – 98% probability of rotator cuff tear if all 3 of the following are present:
- Supraspinatus weakness
- External rotation weakness
- Positive impingement sign(s)
Jobe’s test examination and positive test
Supraspinatus: place the shoulder in 90° of abduction and 30° of forward flexion and internally rotate the arm so that the thumb is pointing toward the floor
Weakness with active resistance suggests a supraspinatus tear
Lift- off test
Subscapularis: internally rotate arm so dorsal surface of hand rests on lower back; patient instructed to actively lift hand away from back against examiner resistance (use Belly Press Test if too painful)
Inability to actively lift hand away from back suggests a subscapularis tear
Posterior Cuff Test
Infraspinatus and teres minor: arm positioned at patient’s side in 90° of flexion; patient instructed to externally rotate arm against the resistance of the examiner
Weakness with active resistance suggests posterior cuff tear
Neers Test
Rotator cuff impingement: passive shoulder flexion
Pain elicited between 130-170° suggests impingement
Hawkins-Kennedy Test
Rotator cuff impingement: shoulder flexion to 90° and passive internal rotation
Pain with internal rotation suggests impingement
Painful arc test
Rotator cuff tendinopathy: patient instructed to actively abduct the shoulder
Pain with abduction >90° suggests tendinopathy
Speed’s Test
Apply resistance to the forearm when the arm is in forwa d flexion with the elbows fully extended
Pain in the bicipital groove
O’Brien’s Test
SLAP lesion: forward flexion of the arm to 90 degrees while keeping the arm extended. Arm is adducted 10-15 degrees. Internally rotate the arm so thumb is facing down and apply a downward force. Repeat the test with arm externally rotated
Pain or clicking in the glenohumoral joint in internal rotation but not external rotation
Acromioclavicular Joint pathology
subluxation or dislocation of AC joint
which ligaments attach clavicle to scapula
AC
CC
AC joint pathology mechanism
• fall onto shoulder with adducted arm or direct trauma to point of shoulder
AC joint pathology clinical features
- pain with adduction of shoulder and/or palpation over AC joint
- palpate step deformity between distal clavicle and acromion (with dislocation)
- limited ROM
AC joint pathology investigations ;
X-rays: bilateral AP, Zanca view (10-15° cephalic tilt), axillary
AC joint pathology treatment
• non-operative
■ sling 1-3 wk, ice, analgesia, early ROM and rehabilitation
• operative
■ indication: Rockwood Class IV-VI (III if labourer or high level athlete)
■ number of different approaches involving AC/CC ligament reconstruction or screw/hook plate insertion
AC joint pathology potential complications
pneumothorax or pulmonary contusion
Rockwood classification of AC joint separation and management of each
Grade 1
Joint sprain, absence of complete tear of either ligament
Non-operative
Grade II
Complete tear of AC ligament, incomplete tear of CC ligament, without marked elevation of lateral clavicular head
Non-op
Grade III
Complete tear of AC and CC ligaments, >5 mm elevation at AC joint, superior aspect of acromion is below the inferior aspect of the clavicle
Most non-operative, operative if labourer or high level athlete
Will heal with step deformity, although most fully functional in 4-6 mo
IV-VI
Based on the anatomical structure the displaced clavicle is in proximity to
Operative in most cases
Clavicle fracture incidence of types
proximal (5%), middle (80%), or distal (15%) third of clavicle
Clavicle fracture common population
children - unites rapidly without complications
Clavicle fracture mechanism
fall on shoulder (87%), direct trauma to clavicle (7%), FOOSH (6%)
Clavicle fracture clinical features
- pain and tenting of skin
* arm is clasped to chest to splint shoulder and prevent movement
Clavicle fracture investigations
- evaluate NVS of entire upper limb
- X-ray: AP, 45° cephalic tilt (superior/inferior displacement), 45° caudal tilt (AP displacement)
CT: useful for medial physeal fractures and sternoclavicular injury
Clavicle fracture treatment
• medial and middle-third clavicle fractures
■ simple sling x 1-2 wk
■ early ROM and strengthening once pain subsides
■ if fracture is shortened >2 cm, consider ORIF
• distal-third clavicle fractures
■ undisplaced (with ligaments intact): sling x 1-2 wk
■ displaced (CC ligament injury): ORIF
Clavicle fracture specific complications /associated injuries
- cosmetic bump usually only complication
- shoulder stiffness, weakness with repetitive activity
- Up to 9% of clavicle fractures are associated with other fractures (most commonly rib fractures)
- Majority of brachial plexus injuries are associated with proximal third fractures
- pneumothorax, brachial plexus injuries, and subclavian vessel (all very rare)
Frozen shoulder (adhesive capsulitis) definition
disorder characterized by progressive pain and stiffness of the shoulder, usually resolving spontaneously after 18 mo
Frozen shoulder (adhesive capsulitis) conditions associated with increased incidence
- Prolonged immobilization (most significant)
- Female gender
- Age >49 yr
- DM (5x)
- Cervical disc disease
- Hyperthyroidism
- Stroke
- MI
- Trauma and surgery
- Autoimmune disease
Frozen shoulder (adhesive capsulitis) mechanism
• primary adhesive capsulitis
■ idiopathic, usually associated with DM
■ usually resolves spontaneously in 9-18 mo
• secondary adhesive capsulitis ■ due to prolonged immobilization ■ shoulder-hand syndrome: CRPS/RSD characterized by arm and shoulder pain, decreased motion, and diffuse swelling ■ following MI, stroke, shoulder trauma ■ poorer outcomes
Frozen shoulder (adhesive capsulitis) clinical features
• gradual onset (weeks to months) of diffuse shoulder pain with:
■ decreased active AND passive ROM
■ pain worse at night and often prevents sleeping on affected side
■ increased stiffness as pain subsides: continues for 6-12 mo after pain has disappeared
Frozen shoulder (adhesive capsulitis) investigations
X-ray: AP (neutral, internal/external rotation), scapular Y, axillary
■ may be normal, or may show demineralization from disease
Frozen shoulder (adhesive capsulitis) treatment
• freezing phase
■ active and passive ROM (physiotherapy)
◆ NSAIDs and steroid injections if limited by pain
• thawing phase
■ manipulation under anesthesia and early physiotherapy
◆ arthroscopy for debridement/decompression
Stages of adhesive capsulitis
- Freezing phase: gradual onset, diffuse pain (lasts 6-9 mo)
- Frozen phase: decreased ROM impacting functioning (lasts 4-9 mo)
- Thawing phase: gradual return of motion (lasts 5-26 mo)
