AC Joint separation – Direct force by far most common mechanism of Acromioclavicular Separation Treatment ■ Fall onto point of shoulder AC Joint separation ( acromioclavicular joint) traumatic injury
■ Acromion gets driven downward and clavicle is stabilized by sternoclavicular (SC) ligaments
■ Sequence of ligamentous injuries: acromioclavicular (AC) ligaments, coracoclavicular (CC) ligaments, deltoid and trapezial muscle attachments, skin
■ Inferior dislocation (type VI separation) likely caused by downward force on clavicle
■ Injury may also be caused by indirect force with humeral head being driven into acromion
➣ Will cause no damage to CC ligaments

■ A common athletic injury

➣ Football
➣ Hockey
➣ Lacrosse
➣ Bicycling (esp. mountain biking)
➣ Snowboarding

■ Motorcycle accidents

➣ Tend to be complex with associated injuries
■ Patients report pain, swelling at AC
■ Chronically may have deformity, clicking, pain

Physical exam of Acromioclavicular Separation

■ Inspection of deformity
➣ Rule out posterior buttonholing of clavicle through deltotrapezial fascia
■ Neurovascular and rotator cuff strength exam
6 Acromioclavicular Separation
■ Palpation of AC and CC regions
■ Cross-body adduction
■ Injuries to rule out acutely
➣ Clavicular shaft fracture
➣ Acromion and coracoid fractures
➣ Brachial plexus injuries
➣ SC joint injuries
➣ Pneumothorax
➣ Scapulothoracic dissociation

physiotherapy management in Fractures

■ Chronically must rule out other sources of pain

➣ SLAP tear
➣ Cervical radiculopathy
➣ Rotator cuff tear

Studies of Acromioclavicular Separation & Treatment

■ Preferably done standing
■ AP (Zanca view)
➣ 15◦ cephalic tilt to avoid superimposition of AC joint on scapula
➣ Reduced exposure needed as in AP view of glenohumeral joint
■ Axillary view
➣ Rule out posterior displacement of clavicle
➣ Rule out coracoid and acromion fractures
➣ Film other side if questionable
■ Standing AP view of both shoulders
➣ Measure CC distances and calculate % increase on affected side
➣ CC distance normally 1.0–1.3 cm
■ Weighted views
➣ Help distinguish type II from type III
➣ Not needed, as they seldom change treatment plan or decision
to perform surgery
■ MRI
➣ Can delineate ligamentous injury and arthritis, useful for surgical planning

Differential diagnosis

■ Lateral clavicle fracture
■ Periosteal sleeve fracture
■ Bipolar AC separation + SC joint injury
■ Combined AC separation + coracoid process fracture
■ Glenohumeral joint dislocation

Type and grades of Acromioclavicular Separation & Treatment

Acromioclavicular Joint separation and shoulder separation grades

■ Classification system based on injury to AC and CC ligaments and severity and direction of displacement of clavicle
➣ Grade I Acromioclavicular Joint separation: Sprain of AC ligaments; CC ligaments intact; no increase in CC distance
➣ Grade II Acromioclavicular Joint separation: Disruption of AC ligaments and sprain of CC ligaments; increase in CC distance <25%; weighted views would show equal CC distances

➣ Grade III Acromioclavicular Joint separation : Disruption of AC and CC ligaments; CC distance 25–100%; deltotrapezial fascia is intact

➣Grade IV Acromioclavicular Joint separation : Disruption of AC and CC ligaments; clavicle is posteriorly displaced into deltotrapezial fascia; may not have significant superior displacement

➣ Grade V Acromioclavicular Joint separation: Disruption of AC and CC ligaments; marked superior displacement of clavicle with CC distance of 100–300%; torn deltotrapezial fascia

➣Grade VI Acromioclavicular Joint separation: Disruption of AC ligaments +/− CC ligaments; inferior displacement of clavicle in either subacromial (CC ligaments intact) or sub coracoid (CC ligaments disrupted) location; subcoracoid dislocation associated with severe injury, rib fractures, and clavicle fracture

■ Treatment AC Joint separation

➣ Types I and II

✅ Ice and sling for comfort for 1–2 weeks

✅ Return to activity when full pain-free range of motion present

✅ May take longer in type II injuries

✅ Kenny Howard brace – presses down on clavicle and pushes arm upwards

✅ Must be worn 24 hours a day

✅ Can cause skin breakdown over clavicle and anterior interosseous nerve palsy

✅ Pts w/ type II may develop persistent symptoms in future secondary to posttraumatic degeneration, osteolysis of distal clavicle, loose cartilage fragments, or unstable meniscus

✅ Treat with distal clavicle excision +/− CC stabilization

✅ Distal clavicle excisions fare poorly if grade II injury present

➣ Type III

✅ Operative vs. nonoperative treatment remains controversial

✅ Literature unclear on the matter, but careful review reveals that recent trend is to opt for nonoperative treatment 8 Acromioclavicular Separation

✅ Patients treated nonoperatively recover sooner, with no difference in strength or pain

✅ Exceptions to this are in overhead laborers and perhaps throwing athletes

✅ Nonoperative treatment
Sling for 2–4 weeks

✅ Early pendulum and ROM exercises

✅ Begin strengthening at 4–6 weeks

✅ Avoid contact sports for 4–8 weeks

➣ Types IV and V

✅ Operative treatment recommended

✅ Early (first 2 weeks) surgery results are better than late surgery

✅ Type IV tends to be more painful

✅Type V symptomatology generally relative to degree of displacement

➣ Type VI

✅ Operative treatment recommended

✅ Excision of distal clavicle facilitates reduction

✅ Operative treatment

✅ Acute indications are grades IV, V, and VI separations

➣ Relative indications include grade III separations in overhead laborers

➣ >30 operative techniques described
➣ Transfer of coracoacromial ligament with or without CC fixation
(Weaver-Dunn)
✅ Distal clavicle may or may not be resected
✅ Late AC joint degeneration avoided with resection
✅ CC fixation achieved with suture or synthetic material through a drill hole in the clavicle
✅ Placing cerclage around clavicle causes abnormal anteriorization of clavicle and potential for material to cut through clavicle
✅ Avoid use of permanent synthetic tapes (Dacron or Mersilene) due to foreign body reaction and late infection

➣ CC fixation

✅ Screw placed through clavicle into coracoid
✅ Biomechanically strong
✅ Perform in conjunction with repair of ligaments when done acutely
✅ Requires removal at 8 weeks
✅ Technically difficult
✅ Easy to drill into coracoid but often screw can “blow out” the coracoid
✅ May abnormally anteriorize the clavicle

➣ AC fixation

✅ Kirschner wires across AC joint
✅ Can be done percutaneously without repair of CC ligaments or open with repair
✅ Violates joint and can lead to arthritis
✅ Requires second procedure for hardware removal
✅ Pins can migrate!
✅ Never use smooth pins

➣ Dynamic muscle transfer
✅ Transfer of coracoid with short head of biceps to clavicle
✅ Exchange of a dynamic constraint for a static one
✅ Half have continued aching
✅ Risk of injury to musculocutaneous nerve

■ Rehabilitation
➣ Sling for 6 weeks
➣ Daily pendulum exercises started at week 1
➣ No active forward flexion or abduction for 6 weeks
➣ No lifting of any kind for 6 weeks
➣ Start progressive active range of motion and strengthening at 6 weeks

Disposition
N/A

Prognosis

■ Nonoperative treatment of grade III injuries appears to be equivalent to surgery
➣ Earlier return with nonoperative treatment
■ Non operated athletes may return to play when range of motion full and strength normal
■ Operatively treated athletes should avoid contact for 6 months
■ Complications of surgery
➣ Loss of reduction
➣ Infection
➣ Deltoid dehiscence
➣ Calcification of CC ligaments (not a problem; seen also in non operative treatment)

➣ Erosion of fixation through clavicle
➣ Foreign body reaction to synthetic tapes

Caveats and Pearls

■ Results of surgery done within a few weeks of injury are superior to those done chronically
■ Grade IV separations don’t always have superior displacement
■ No need for aggressive rehabilitation
■ A small amount of superior displacement can be expected after reconstruction
■ Conoid ligament (medial) controls vertical stability
■ Trapezoid ligament (lateral) controls axial load of joint
■ Superior and posterior AC ligaments control anterior-posterior
■ Only 5–8◦ of motion at AC joint
➣ Clavicle does rotate 40–50◦ with full elevation of shoulder
➣ Upward rotation of clavicle is combined with downward rotation of the scapula, controlled by CC\ ligaments (synchronous scapulo clavicular rotation)
➣ AC or CC fixation has little effect on shoulder motion