01Approach to the Critical Patient/attcp63

Immediate priorities

›Injury severity triage

›Low-energy isolated mechanism

›Sports or fall onto point of shoulder

›Likely isolated AC injury

›High-energy mechanism

›Motor vehicle collision

›Fall from height

›Screen for polytrauma and associated injuries

›If high-energy, apply trauma primary survey before focusing on shoulder

›ATLS ABCDE sequence

›Defer isolated-extremity workup until life threats cleared

›Airway and breathing threats

›Pneumothorax risk

›Ipsilateral chest wall impact

›Decreased breath sounds

›Tracheal or great-vessel proximity injury

›Posterior medial clavicle displacement

›Stridor or dysphagia

›If respiratory distress with chest trauma, immediate chest imaging

›Upright chest radiograph

›eFAST for pneumothorax

›Limb-threatening features

›Skin tenting by distal clavicle

›Type IV to VI marker

›Pressure necrosis risk

›Open injury

›Skin breach over joint

02History/hx75

Presentation pattern

›Core symptom complex

›Superior shoulder pain

›Localized to AC joint

›Worse with cross-body adduction

›Pain with overhead reaching

›Limits dressing and lifting

›Limits sport participation

›Visible deformity

›Step-off or prominent bump

›Clicking or popping sensation

›Onset and timing

›Acute onset at moment of trauma

›Immediate pain and swelling

›Functional loss from outset

›Insidious onset without trauma

›Consider distal clavicle osteolysis

›Common in weightlifters

Mechanism of injury

›Direct mechanisms

›Direct blow to lateral or superior shoulder

›Most common mechanism

›Arm adducted at impact

›Fall onto the acromion

›Point-of-shoulder contact

›Cycling fall pattern

›Indirect mechanisms

›Fall onto outstretched hand

03Physical Exam/exam62

Inspection and palpation

›Visual deformity assessment

›Step-off at AC joint

›Prominent elevated distal clavicle

›Compare with contralateral shoulder

›Swelling and ecchymosis

›Localized over AC joint

›Skin tenting in high-grade injury

›Posterior prominence

›Clavicle through trapezius suggests Type IV

›Inferior displacement suggests Type VI

›Palpation findings

›Point tenderness over AC joint

›Maximal directly over joint line

›Crepitus with motion

›Distal clavicle mobility

›Increased anteroposterior translation

›Vertical instability

Provocative and stability tests

›Piano key sign

›Downward pressure reduces deformity

›Springs back on release

›Indicates Type III or higher instability

›Cross-body adduction (Scarf) test

›Pain with passive horizontal adduction

›Sensitivity approximately 77%

›Localizes pain to AC joint

›O'Brien active compression test

04Differential Diagnosis/ddx39

Traumatic shoulder differentials

›Bony injuries

›Distal clavicle fracture

›ICD-10 S42.031A for displaced lateral clavicle fracture

›Neer Type II disrupts CC ligaments

›Coracoid fracture

›Associated with high-grade AC injury

›Point tenderness over coracoid

›Proximal humerus fracture

›Greater tuberosity tenderness

›Different deformity pattern

›Joint and soft-tissue injuries

›Glenohumeral dislocation

›Loss of normal shoulder contour

›Arm held in abduction and external rotation

›Sternoclavicular joint injury

›Medial clavicle tenderness

›Posterior dislocation airway risk

›Rotator cuff tear

›Weakness on specific testing

›May coexist with AC injury

Non-traumatic and chronic mimics

›AC joint pathology

›Distal clavicle osteolysis

›ICD-10 M89.51 osteolysis shoulder region

›Insidious onset in weightlifters

›Radiographic distal clavicle resorption

›AC joint osteoarthritis

05Laboratory Tests/lt24

Routine testing

›Isolated AC separation labs

›No routine labs indicated

›Diagnosis is clinical and radiographic

›Labs reserved for specific concerns

›Analgesia safety considerations

›Renal function before sustained NSAID use

›Bleeding history before NSAID

Infection workup

›Subacute or chronic presentation with infection signs

›Inflammatory markers

›CBC for leukocytosis

›ESR and CRP elevation

›Microbiology

›Blood cultures before antibiotics

›Joint aspirate culture if septic arthritis suspected

›If erythema warmth and fever, evaluate for septic AC joint

›Joint aspiration for cell count

›Crystal analysis to exclude gout

Preoperative labs

›Surgical candidates

›Standard preoperative panel

›CBC and electrolytes

›Coagulation studies per protocol

›Type and screen when indicated

›Reconstruction with graft

›Institutional protocol

06Diagnostic Tests/dt95

Scoring Systems

›Rockwood classification

›Type I

›Partial AC ligament tear with intact CC ligaments

›Normal CC distance

›Nonoperative sling management

›Type II

›Complete AC tear with partial CC tear

›Normal or slightly increased CC distance

›Nonoperative management

›Type III

›Complete AC and CC ligament tears

›CC distance increased up to 100% versus contralateral

›Controversial conservative versus surgical

›Type IV

›Clavicle displaced posteriorly through trapezius

›Variable CC distance

›Surgical management

›Type V

›CC distance increased 100% to 300%

›Severe superior displacement

›Surgical management

›Type VI

›Clavicle displaced inferiorly under acromion or coracoid

›Rare and associated with severe trauma

›Surgical management

›ISAKOS subclassification of Type III

›Type IIIA stable

›No overriding on cross-arm adduction view

›Favors conservative management

›Type IIIB unstable

›Clavicle overrides acromion

›Favors surgical consideration

›Diagnostic adjuncts

›Diagnostic AC joint injection

›Lidocaine confirms joint as pain source

›Useful in chronic or equivocal cases

MRI

›Role in AC separation

›Not routinely indicated acutely

›Diagnosis usually radiographic

›Reserve for equivocal cases

›Problem-solving indications

›CC ligament integrity in equivocal injury

›Concomitant SLAP or rotator cuff injury

›Chronic AC joint pain evaluation

›Findings

›Ligament discontinuity and edema

›Distal clavicle marrow edema in osteolysis

›Limitations

›Cost and availability

›Not needed for clear high-grade injury

›ACR Appropriateness Criteria reserve for selected cases

CT

›Role in AC separation

›Rarely needed

›Reserved for complex patterns

›Not first-line for grading

›Indications

›Complex fracture characterization

›Preoperative planning

›Coracoid or glenoid involvement

›Findings

›Three-dimensional displacement assessment

›Associated fracture delineation

›Considerations

›Radiation exposure

›Limit in young athletes

›Use only when radiograph insufficient

Ultrasound

›Point-of-care ultrasound

›CC ligament assessment

›Sensitivity approximately 89% versus MRI

›Specificity approximately 90% versus MRI

›Bedside AC joint evaluation

›Joint widening and step-off

›Dynamic comparison with contralateral side

›Advantages

›No radiation

›Rapid ED adjunct

›Limitations

›Operator dependent

›Requires musculoskeletal expertise

›Adjunct rather than definitive grading tool

Radiographs

›First-line imaging

›Standard views

›AP shoulder

›Axillary lateral to detect posterior displacement

›Zanca view with 10 to 15 degree cephalic tilt

›Comparison imaging

›Contralateral side for CC distance

›Increased CC distance indicates higher grade

›Specialized views

›Cross-body adduction (Alexander) view

›Distinguishes Type IIIA from IIIB

›Demonstrates clavicle overriding acromion

›Weighted stress views

›Historically used and now falling out of favor

›Delphi consensus finds AP and axillary sufficient

07Disposition/dispo42

Discharge versus consultation

›ED discharge candidates

›Type I to III injuries

›Sling and analgesia provided

›Orthopedic follow-up within 1 to 2 weeks

›Neurovascularly intact

›Normal distal pulses

›Intact axillary nerve function

›In-ED orthopedic consultation

›High-grade injury

›Type IV to VI

›Skin tenting at risk of necrosis

›Open injury or neurovascular compromise

›Wound over joint

›Diminished pulses or progressive deficit

›Associated fractures requiring urgent care

›Displaced clavicle fracture

›Coracoid fracture

Admission and observation

›Admission indications

›Polytrauma

›Concurrent injuries requiring inpatient care

›Hemodynamic concerns

›Failed reduction of high-grade dislocation

›Persistent skin compromise

›Operative timing planning

›Observation role

›Generally not required

08Treatment/t90

Analgesia

›Multimodal pain control

›First-line oral analgesia

›Acetaminophen 650 to 1000 mg PO every 6 hours, maximum 4 g per day

›Ibuprofen 400 to 600 mg PO every 6 to 8 hours

›Naproxen 250 to 500 mg PO every 12 hours

›Topical options

›Topical NSAID for localized pain

›Adjunct to oral analgesia

›Opioid use

›Use sparingly if at all

›Short course only for severe pain

›NSAID precautions

›Short-course use does not impair ligament healing

›Avoid prolonged use

›Reassess renal and GI risk

›Avoid in contraindicated patients

›Renal impairment

›Active peptic ulcer disease

Immobilization and ice

›Sling immobilization

›Sling for comfort

›Typically 2 weeks

›Jones strapping offers no clear advantage over sling

›Ice application

›15 to 20 minutes several times daily

›Reduces swelling in acute phase

›Activity modification

›Avoid overhead and cross-body loading

›Protect healing ligaments

›Limit lifting on affected side

Grade-specific management

›Types I and II nonoperative

›Conservative protocol

›Sling 2 weeks then early gentle ROM

›Pendulum exercises as pain allows

›Progressive rehabilitation

›ROM then scapular stabilization

›Rotator cuff strengthening then sport-specific conditioning

›Return-to-activity criteria

›Pain-free with full ROM

›Symmetric strength

›Type III individualized

›Initial conservative trial for most

›Sling 2 weeks then rehabilitation

›Up to 80% have good outcomes without surgery

›Early surgical referral candidates

›High-demand athletes and overhead workers

›Military personnel

›Type IIIB unstable injuries

›If conservative treatment fails after 3 to 6 months, surgical reconstruction

›Persistent pain and dysfunction

›Scapular dyskinesis

›Types IV to VI surgical

›Orthopedic operative management

›Reduction and ligament reconstruction

›Urgent if skin compromise

›Surgical techniques

›CC ligament reconstruction with autograft or allograft

›Hook plate fixation

›Suture-button or arthroscopic-assisted techniques

Rehabilitation and return to sport

›Postsurgical rehabilitation

›Early phase

›Sling 2 to 4 weeks then pendulum exercises

›Active ROM at 4 to 6 weeks

›Strengthening phase

›Resisted exercises at 6 weeks

›Return to sport at approximately 4.5 to 6 months

›Return-to-sport data

›Operative outcomes

›Pooled return-to-sport rate 91.5%

›85.6% return to pre-injury level

›Mean time to return approximately 5.7 months

›Nonoperative timeline

›Mean return approximately 52 days

›Faster than operative mean of 127 days

›Return criteria

›Pain-free with full ROM

›Symmetric strength and sport-specific testing

Adjunct considerations

›Corticosteroid injection

›Reserved for chronic AC pain or osteoarthritis

›Diagnostic and therapeutic

›Not standard in acute traumatic setting

›Procedural cautions

›Avoid in suspected infection

›Limit repeat injections

›Nutrition for healing

›Adequate protein and calories

›Supports tissue repair

›Maintain hydration during rehabilitation

›Bone health

›Adequate calcium and vitamin D

›Address metabolic bone disease

09Special Populations/sp51

Pregnancy

›Imaging approach

›Radiographs with shielding

›Shoulder is remote from uterus

›Minimal fetal exposure with abdominal shielding

›Avoid unnecessary CT

›Use ultrasound adjunct when feasible

›MRI without contrast if advanced imaging needed

›Analgesia safety

›Acetaminophen first-line

›Preferred analgesic in pregnancy

›Avoid exceeding maximum dose

›NSAID avoidance

›Avoid after 20 weeks gestation

›Risk of oligohydramnios and ductal closure

›Opioids minimized

›Short course only if essential

›Neonatal withdrawal risk near term

Geriatric

›Modified clinical approach

›Lower-energy mechanisms cause injury

›Ground-level falls

›Osteoporotic distal clavicle

›Concurrent fracture risk

›Distal clavicle fracture more likely

›Screen for proximal humerus fracture

›Treatment considerations

›Conservative management favored

10Background/b56

Epidemiology

›Frequency and burden

›Proportion of shoulder injuries

›Approximately 9% of all shoulder injuries

›Up to 40% in elite contact-sport athletes

›Demographic distribution

›Male predominance

›Peak age 20 to 49 years

›Grade distribution

›Vast majority are Types I to III

›Types IV to VI are uncommon

›Outcomes data

›Type III nonoperative outcomes

›Up to 80% have good outcomes without surgery

›No significant functional difference versus surgery at one year

›Distal clavicle osteolysis incidence

›Approximately 6% after AC separation

›Overuse form in weightlifters

Pathophysiology

›Ligamentous anatomy

›Acromioclavicular ligaments

›Provide horizontal stability

›Torn first in injury progression

›Coracoclavicular ligaments

›Conoid and trapezoid components

›Provide vertical stability

›Injury progression

›Sequential ligament failure

11Patient Discharge Instructions/pdi24

copy discharge instructions

›Diagnosis explanation

›You have a separated shoulder at the AC joint

›Most separations heal without surgery

›A visible bump may remain and usually does not affect function

›Home care

›Wear the sling for comfort for about 2 weeks

›Apply ice for 15 to 20 minutes several times a day

›Take acetaminophen and anti-inflammatory medication as directed

›Begin gentle pendulum movements as pain allows

›Activity guidance

›Avoid heavy lifting and overhead reaching until cleared

›Avoid contact sports until pain-free with full motion and normal strength

›Follow the prescribed rehabilitation progression

›Return to ER red flags

›Worsening deformity or new step-off

›Increasing pain despite treatment

›Numbness tingling or weakness in the arm or hand

›Skin over the bump turning pale or breaking down

›Inability to move the shoulder after initial improvement

›Fever wound redness or drainage after surgery

›Follow-up

›Orthopedic or sports medicine follow-up within 1 to 2 weeks

›Type I may follow up with primary care

›Keep scheduled reassessment appointments

12References/r12

Guidelines and key sources

›Clinical guidance

›Simon LM et al, Acute Shoulder Injuries in Adults, American Family Physician 2023

›ACR Appropriateness Criteria Acute Shoulder Pain 2024 Update

›Team Physician Consensus Statement on musculoskeletal injuries 2024

›Evidence and systematic reviews

›Cochrane review of surgical versus conservative treatment of AC dislocation 2019

›Berthold DP et al, Current Concepts in AC Joint Instability, BMC Musculoskeletal Disorders 2022

›Systematic reviews of return to sport after AC injury

›Coding standards

›ICD-10 S43.50 series acromioclavicular joint sprain

›ICD-10 M89.51 osteolysis shoulder region

›SNOMED CT acromioclavicular joint injury disorder concept

Evidence & Review

Evidence & Review