AcromioClavicular Joint Injury

Courtesy: Ali Noorani, Shoulder Surgeon, London, UK

ACROMIOCLAVICULAR JOINT INJURIES

Objectives

• ACJ Joint Anatomy & Stability
• Classification of ACJ Instability
• Management of Acute Injuries
• Management of Chronic Injuries
• Techniques for fixation

Stability

STATIC

• Every joint relies on Ligaments – acromioclavicular and coracoclavicular, bony Congruency and muscles around it in addition to a good functioning neurological system
• CC ligaments constitutes of conoid and trapezoid parts

DYNAMIC
– Deltotrapezial Fascia

Anatomy

AC Joint Anatomy
– Diarthrodal Joint – Variety of Movements
– Intra-articular Disc (meniscus)
– Surrounded by capsule
– Thickest superiorly
– Thinnest inferiorly

Age & Diagnosis of Shoulder Pathologies

– 10 to 30 years
Instability ( Glenohumeral Joint & AC Joint )
Internal & Secondary Impingement

– 30 to 50 years
Primary Impingement Syndrome
Frozen Shoulder
AC Joint Pain

– 50 to 80 years
Full Thickness Cuff Tears
Arthritis

AC Separations

• Prevalence of Type 3 or higher- 14.5/100k per year
• Incidence depends on activity: 32% of professional Rugby players, 9% to 12% of traumatic shoulder injuries
• Associated intra-articular pathology> 15 %

Classification of AC Joint Separation

Type I
Sprain of the joint

Type II

• Some disruption of the AC ligaments
• Non-surgical injury’s only requiring rest and NSAIDs

Type III

• Superior dislocation of the AC joint with ruptured AC and CC ligaments
• TO FIX OR NOT TO FIX?
• Remains Controversial

Type IV

• Posterior displacement

Type V

• Highly Elevated

Type VI

• Inferior displacement
• All require surgical intervention

 

Treatment:

• 1 & 2 – These are stable and may be treated conservatively
• 3 Usually Non Operative initially. Consider Operative for Sports ( Throwers/Contact)
• 4/5 – these are unstable and require surgical management
• 6 Rare but Fix it

Surgical Considerations for type 3

Two different approaches

1.Fix Acutely

• Heavy Laborers
• High level athletes
• Patients not willing to accept cosmetic deformity
• Trade bump for Scar

2. Conservative approach

• Rest
• Ice
• Anti-inflammatories
• Continued pain or fatigue for > 3months = Surgery
• Usually done with addition of biologic graft

Classification

• Flawed. Not a linear deformity but 3D Rotational Deformity
• X-rays can show dynamic improvement
• 4/5 is probably the same
• Examination more important than the X-ray in decision making
• Low intra and inter observer reliability for the Rockwood classification

Acute or Chronic ACJ

• Acute 6 weeks
• Aim for Reconstruction
• Allograft, Autograft or Synthetic Ligament +/- Additional Stability
  e.g Dog-Bone or Hook Plate

Surgical Treatment for Acute Injuries

• Address All Stabilisers of the Joint
• Periosteal sleeve avulsion of CC ligaments.
• Reduce Clavicle and hold it
• Stable e.g Dog Bone or Hook plate
• Repair Posterior Capsule of Joint
• Avoid resection of lateral end of clavicle. Remove IA Disc.
• Avoid further damage to Deltoid and Trapezius
• Mason-Allen repair of Deltotrapezial fascia

Surgical Treatment for Chronic Injuries

• Address All Stabilisers of the Joint
• Reconstruction of CC +/- AC ligaments & hold it stable e.g Dog Bone or Hook plate
• Repair Posterior Capsule of Joint
• Avoid resection of lateral end of clavicle. Remove IA Disc.
• Avoid further damage to Deltoid and Trapezius
• Mason-Allen repair of Deltotrapezial fascia

AC Joint Reconstruction

Important Considerations:

• Arthroscopic Technique (address associated pathology- 18% to 50% in reports)
• Open Technique Repairs the Deltotrapezial fascia and capsule
• Consider Combination
• Strength of construct
• Potential Complications

AC Joint Surgery

• Bosworth screw
• Weaver-Dunn
• Hook plate
• Tightrope
• Surgilig/Lockdown/Synthetic Ligament
• Auto or Allograft
• Arthrex Dog-Bone

ACCR Technique

• Anatomic Coracoclavicular Reconstruction
  “Mazzocca” technique
  Open technique for chronic AC reconstruction
  Graft under coracoid using fibre wires and screws

Current Challenges in AC Joint Repair

• Hook Plate provides good stability but need removal.
• Risk of Acromion Injury and Cuff Injury
• Lockdown (Double braided Polyethyleneterephthalate (PET))
• Corocoid Fracture
• Musculocutaneous Nerve Injury
• Mal-Reduction or Residual Instability
• AC Internal Brace

Anterior/Posterior Stabilization with

• AC Internal Brace in conjunction with CC ligament fixation

Acromion:

• 3.5 mm BioComposite’M SwiveLocke

Distal Clavicle:

• 4.75 mm BioComposite SwiveLock
• FiberTape

Rehabilitation after ACJ Fixation

No Hand behind back, cross arm adduction, Any elevation >90, Extension and abduction
Remove Plate 3-5 Months

Key Points

• Shoulder Girdle / Scapula Injury
• Grade less important than assessment
• Rehab very Important
• Address Static and Dynamic Stabilizers
• Acute needs Stability
• Chronic needs Stability & Augmentation