ACJ Dislocation

Type 3 ACJ Dislocation

Anatomy

 

Synovial joint with hyaline cartilage

 

Has fibrocartilage intra-articular disc

- complete or incomplete

- usually degeneration by 4th decade

 

Clavicle may lie superior to acromion in normal population

 

Acromioclavicular Ligaments

 

ACJ capsule

- strongest superiorly

- horizontal / AP stability

 

Coracoclavicular Ligaments / CCL

 

Primary restraint to superior translation

- primary suspensory ligament of upper limb

 

Trapezoid Ligament (anterolateral)

- anterolateral on coracoid

- inserts trapezoid ridge also anterolateral to conoid

- almost horizontal in sagittal plane

- primary restraint to axial compression

 

Conoid Ligament (posteromedial)

- arises postero-medial to trapezoid

- inverted cone

- inserts conoid tubercle

- apex of posterior clavicular curve

- junction lateral & medial 2/3

- lies vertically

- primary restraint to superior and anterior translation

 

Delto-trapezial fascia

- dynamic stabiliser

 

Motion at ACJ

 

Only small 5-8o

- 40o at SC joint

- motion is at scapulo-thoracic joint rather than ACJ

 

Aetiology

 

Usually direct force onto adducted shoulder joint

- clavicle remains in normal position

- arm falls down

 

Examination

 

Usually clinically obvious

 

Grade 3 ACJGrade 3 ACJ

 

Allman grades I-III 1967 / Rockwood modified 1989 Classification

 

I     ACJ sprain

 

II    ACJ Disrupted & CCL intact / sprained

 

ACJ Dislocation Grade 2

 

III  Rupture ACJ & CCL 

- displaced > 100% of clavicular width

 

Grade 3 ACJ Dislocation

 

IV   Into trapezius

- can be easily missed

- need axillary lateral

 

Type IV ACJ APType IV ACJ Axillary LateralType IV ACJ

 

V     High dislocation > 1 x clavicle width

- disrupted trapezius & deltoid

- end of clavicle subcutaneous

 

ACJ Dislocation Type 5

 

VI    Subcoracoid dislocation

 

X-rays

 

Zanca view

- specific for ACJ

- 10ocephalad, 50% voltage

 

Stress views

- occasionally used

- hold weights in each arm

- bilateral xray

 

Normal 

- 50% overriding clavicle

- 2% under riding

- 29% incongruent

- joint width 0.5-7 mm

 

Management

 

Type I

 

Symptoms 7-10 days

- RICE

- Avoid heavy stress & contact sport till FROM & no pain to palpation

- 2/52

 

Type II

 

Sling 2/52

- avoid heavy lifting, contact sports 8-10/52 to allow ligament healing

- OT if Persistent pain

        

Chronic Symptomatic I & II

- trapped capsular ligament / loose articular cartilage / detached meniscus

- excision outer end clavicle if continued symptoma

 

Acute Type III

 

RCT Operative vs Non-Operative

 

Tamaoki et al Cochrane Database 2010

- meta-analysis of 3 RCT

- operative v non operative

- multiple fixation techniques

- no obvious advantage in operative group

- RCT insufficient to decide merit of operative management

 

Surgical Indications

 

Rockwood

- heavy labourer

- < 25 years undecided on career

- not in athlete (will just destroy repair when next falls)

 

Options

 

1.  Hook plate

- reduction of ACJ

- hook under posterior acromion

- allows CC ligaments to heal

- must be removed

- but can mobilise the shoulder at 4-6 weeks with implant in situ

 

Clavicle Hook Plate

 

Gstettner et al J Should Elbow Surg 2008 

- acute injuries

- hook plate or non operatively, patient choice

- 57 v 30

- hook plate removed after 3 months

- 1 hook plate cut up through acromion (still good result)

- 3 superficial infections

- slightly improved constant scores in surgical group

- similar ROM

- improved pain and power scores

 

Risks

- acromial cut out

- clavicle fracture

 

Clavicle Hook Plate Fracture

 

2.  Reconstruction

 

Chronic Symptomatic Grade III

 

Excision distal clavicle

 

Poor results

- convert long high riding clavicle to short high riding clavicle

 

Reconstruction Options

- Phemister technique

- Weaver Dunn

- CCL augmentation (anchors / tightrope)

- CCL Reconstruction

- combinations

 

1.  Phemister technique

 

Technique

- open reduction of ACJ

- 2 x K wires across ACJ

- suture repair AC and CC ligaments

 

Calvo J Should Elbow Surg 2006

- Phemister v Non operative

- similar rates of deformity (i.e. non anatomic reduction) 

- less radiographic OA in non surgically treated cases

- may be that K wires further damage joint

- similar functional results in each

- recommend non operative treatment

 

2.  Weaver Dunn Reconstruction

 

Concept

- reconstruction of CC ligament with coraco-acromial ligament (CAL)

- CA ligament left attached to coracoid

- excise 1.5 (2.5cm original recommendation) lateral clavicle

- CAL taken off anterior acromion with bone fragment

- transferred from acromion to clavicle end / intra-osseous suture repair

 

Supplement with

- hook plate

- Bosworth Screw

- anchor / sutures

- Lars Ligament / Hamstring / allograft

 

3.  CCL Augmentation

 

Technique

- 5 mm anchor with sutures about clavicle

- tightrope constructs

- Bosworth screw

 

Weaver Dunn with Twinfix AnchorACJ Reconstruction TightropeACJ Reconstruction Tightrope

 

4.  CCL Reconstruction

 

Technique

- pass allograft / autograft / LARS around coracoid

- pass around clavicle and suture or

- can pass through drill holes and secure with screws

- second technique risks clavicle fracture

 

Results

 

Tauber et al J Should Elbow Surg 2007

- 12 revision cases of failed Weaver Dunn

- autogenous ST in figure 8 configuration

- through drill holes in clavicle, around coracoid, then over clavicle

- augmented with Bosworth / TBW removed at 3/12

- 4 weeks immobilised, then ROM to 90o for another 8 weeks

- good results, one clavicle fracture from wire

 

Complications 

- intra-operative fracture coracoid

- failure repair (10 - 20%)

- recurrent deformity common in surgical groups

- clavicle fracture (due to sutures or metal work)

- ACJ OA

- continued pain

- posterior dislocation (due to non intact AC ligament)

- NV damage

 

Type IV, V, VI

 

Most recommend surgery

- hook plate / reconstruction acutely

- reconstruction late

 

Technique Weaver Dunn + Augmentation / Reconstruction

 

Approach

- 45o beach chair

- sabre incision over ACJ

- split fascia transversely along the clavicle and onto acromion

- must skeletalise distal end of clavicle to beyond former insertion of conoid and trapezoid

- expose anterior aspect of acromion

- resect 1 cm of distal clavicle with microsagittal saw

- find the CA ligament which will run from anterior acromion down to coracoid

- often a great deal of scar tissue in this area from injury

- expose the coracoid laterally and carefully medially

- take off anterior 5mm of acromion and carefully peel CAL off the underlying SSC

- will need to release some of CAL from coracoid to get sufficient length

 

Reduction / Reconstruction

- reduce clavicle down with preferred technique

- 5mm anchor / tightrope / allograft / autograft / Lars ligament through drill holes

- cross graft at clavicle so gives front to back stability as well as superior / inferior

- place drill holes through distal clavicle

- use 2 fibre wire to weave through CAL under bony fragment

- secure with intra-osseous sutures

 

Post op

- sling for 6/52

- no contact sports for 6/12

 

Post Weaver Dunn with Lars Ligament