Orthopaedics: Shoulder

Shoulder

Shoulder Dislocation

·                 the glenohumeral joint is the most commonly dislocated joint in the body since stability is sacrificed for motion

Prognosis

·                 recurrence rate depends on age of 1st dislocation: <20 yrs = 65-95%; 20-40 yrs = 60-70%; >40 yrs = 2-4%

Specific Complications

·                 tuberosity fracture, glenoid rim fracture (Bankart lesion), humeral head impaction (Hill-Sachs lesion)

·                 rotator cuff or capsular tear, shoulder stiffness

·                 injury to axillary nerve/artery, brachial plexus

·                 recurrent/unreduced dislocation (most common complication)

ANTERIOR SHOULDER DISLOCATION (>90%)

Mechanism

 • abducted and externally rotated arm or blow to posterior shoulder

Clinical Features

·                 pain

·                 arm held in slight abduction, external rotation; internal rotation is blocked

·                 "squared off" shoulder

·                 +ve apprehension test: apprehension with shoulder abduction and external rotation to 90° since humeral head is pushed anteriorly and recreates feeling of anterior dislocation

·                 +ve relocation test: a posteriorly directed force applied during the apprehension test relieves apprehension since anterior subluxation is prevented

·                 +ve sulcus sign: presence of subacromial indentation with distal traction on humerus indicates Inferior shoulder instability

·                 neurovascular exam including:

o       axillary nerve (sensory patch over deltoid and deltoid contraction)

o       musculocutaneous nerve (sensory patch on lateral forearm and biceps coutraction)

Investigations

 • x-rays: AP, trans-sapular, axillary

X-Ray Findings

·                 dislocation

o       axillary view: humeral head is anterior

o       trans-scapular view: humeral head is anterior to the centre of the "Mercedes-Benz sign"

·                 ± Hill-Sachs lesion: divot in posterior humeral head due to forceful impaction of an anteriorly dislocated humeral head against the glenoid rim {Figure 15)

·                 ±bony Banbart lesion: avulsion of the anterior glenoid labrum (with attached bone from the glenoid rim

Treatment

·                 closed reduction with IV sedation and muscle rel.uation

·                 2methods

o       traction-countertraction: assistant stabilizes torso with a folded sheet wrapped across the chest: while the MD applies gentle steady traction (see Figure 14)

o       Stimson: while patient lies prone with arm hanging over table edge, hang a 5lb weight on wrist fur 15-20 min

·                 obtain post-reduction .x-rays

·                 check post-reduction neurovascular status (NVS)

·                 sling x 3 weeks, followed by shoulder rehabilitation

POSTERIOR SHOULDER DISLOCATION (5%}

·                 up to 60-8096 are missed on initial presentation due to poor physical cum and radiographs

Mechanism

·                 adducted, Internally rotated, flexed arm

·                 fall on an outstretched hand (FOOSH)

·                 3 E's (epileptic seizure, EtOH, electrocution)

·                 blow to 81112rior shoulder

Clinical Features

·                 arm is held in adduction and internal rotation; external rotation is blocked

·                 anterior shoulder flattening, prominent coracoid, palpable mass posterior to shoulder

·                 posterior apprehension ("jerk") test with patient supine, 8eJ: elbow and adduct, internally rotate the arm while applying a posterior force to the shoulder; patient will "jerk"' back with the sensation of subluxation

Investigation

·                 x-rays: AP, trans-scapular, axillary

X-Ray Findings

·                 dislocation

o       AP view: partial vacancy of glenoid fosaa (vacant glenoid sJgn) 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)

o       axillary view: humeral head is posterior

o       trans-scapular view: humeral head is posterior to centre of"Mercedes-Benz signo

·                 reverse Hill-Sachs lesion (7596 of cases): divot in anterior humeral head

·                 reverse bony Bankart lesion: avulsion of the posterior glenoid labrum from the bony glenoid rim

Treatment

·                 closed reduction: inferior traction on a flexed elbow with pressure on the back of the humeral head

·                 obtain post-reduction x-rays

·                 check post-reduction neurovascular status

·                 sling 3 weeks, followed by shoulder rehabilitation

Rotator Cuff Disease

·                 rotator cuff consists of 4 muscles that act to stabilize humeral head within the glenoid  fossa

SPECTRUM OF DISEASE: IMPINGEMENT. TENDONITIS, MICRO OR MACRO TEARS

Etiology

·                 compression of rotator cuff tendons (primarily supraspinatus) and subacromial bursa between the head of the humerus and the acromion; leads to bursitis. tendonitis and. If left untreated. can lead to rotator cuff thinning and tear

·                 anything that leads to a narrow subacromial space

 1. glenohumeral muscle weakness leading to abnormal motion ofhumeral head

 2. scapular muscle weakness leading to abnormal motion of acromion

 3. acromial abnormalities such as congenital narrow space or osteophyte formation

Clinical Features

·                 night pain and difficulty sleeping on affected side

·                 pain worse with active motion

·                 weakness and loss of range of motion (e.g. trouble with overhead activities)

·                 tenderness to palpation over greater tuberosity

Table 7. Rotator Cuff Special Tests

lnvestigations

·                 X-rays: AP view may show high riding humerus relative to glenoid, evidence of chronic tendonitis

·                 MRI: coronal/sagittal oblique and axial orientati.Oil8 are useful for assessing full/partial tears and tendinopathy, ± arthrogram: geyser sign (injected dye leaks out ofjoint through rotator cuff tear)

·                 arthrogram: see full thickness tear, difficult to assess partial thickness tears

Treatment and Prognoais

·                 mild ("wear")

o       treatment is non-operative (physiotherapy, NSAIDs)

·                 moderate ("tear")

o       non-operative treatment± steroid Injection

·                 severe ("repair")

o       impingement that is refractory to 2-3 months physio and 1-2 injecti0118

o       may require surgical repair, i.e. acromiopiasty, rotator cuff repair

Acromioclavicular (AC) Joint Pathology

·                 2 main ligaments attach clavicle to scapula; acromioclavicular (AC) and coracoclavicu1a (CC) lig8lllents

Mechanism

·                 fall onto shoulder with adducted arm (fall onto tip of shoulder)

Clinical Features

·                 palpate step deformity between distal clavicle and acromion (with dislocation)

·                 pain with adduction of shoulder and/or palpation over AC joint

·                 limited ROM

Investigations

·                 x-rays: AP, Zanca view (10-lSo cephalic tilt), axillary± stress views (10 lb weight in patient's hand)

Treatment

·                 non-operative (most-common): sling 1-3 weeks, ice, analgesia

·                 operative

o       indicati0118: AC and CC ligaments are both tom and/or clavicle displaced posteriorly

o       procedure: excision ofclateral clavicle with ACJCC ligament reconstruction

Clavicular Fracture

·                 incidence proximal (5%), middle (80%), or distal (IS%) third of clavicle

·                 common in children (unites :rapidly without complications)

Mechanism

·                 fall on shoulder (8796), direct trauma to clavicle (7%}, FOOSH (696)

Clinical Features

·                 pain and tenting of skin

·                 arm is clasped to chest to splint shoulder and prevent movement

Treatment

·                 evaluate neurovascular status of entire upper limb

·                 proximal and middle third clavicular fractures

o       sling X 1-2 weeks

o       early ROM and strengthening once pain subsides

o       if ends overlap >2 cm. consider ORIF

·                 distal third clavicular fractures

o       undisplaced (with ligaments intact): sling x 1-2 weeks

o       displaced (CC ligament injury): ORIF

Speciflc Complications (see General Fracture Complications)

·                 cosmetic bump usually only complication

·                 shoulder stiffness, weakne511 with repetitive activity

·                 pneumothorax. injuries to brachial plexus and subclavian vessel (all very rare)

Frozen Shoulder (Adhesive Capsulitis)

Definition

·                 disorder characterized by progressive pain and lrti1fneas of the shoulder usually resolving spontaneously after 18 months

Mechanism

·                 primary adhesive capsulitis

o       idiopathic, usually ast1ociated with diabetes mellitus

o       may resolve spontaneously in 9-18 months

·                 secondary adhesive capsulitis

o       due to prolonged immobilization

o       shoulder-hand syndrome -type of chronic regional pain syndrome (reflex sympathetic dystrophy) characterized by arm and shoulder pain, decreased motion and diffuse swelling

o       following myocardia infarction, stroke, shoulder trauma

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 months after pain has disappeared

Investigations

·                 x-nys may be normal, or may show demineralization from disease

Treatment

·                 active and passive ROM (physiotherapy)

·                 NSAIDs and steroid injections if limited by pain

·                 MUA (manipulation under aneathesia) and early physiotherapy

·                 arthroscopy for debridement/decompression