ACJ Osteoarthritis

Aetiology

 

Post-traumatic

Idiopathic

 

4 patterns 

 

1. OA with osteophytes 

-  contribute to impingement

 

ACj OAACJ OA copy

 

2. Osteolysis

 

Area of distal clavicle resorption

- due to repetitive microtrauma

- typically weight lifters or manual workers

 

ACj OsteolysisACJ osteolysis

 

3. RA

 

4. Hyperparathyroidism

 

Symptoms

 

Anterosuperior shoulder pain

- difficulty sleeping on affected side

 

Localised to ACJ

 

Signs

 

ACJ OA Clinical Photo

 

Visible deformity / swelling / osteophytes

 

Tenderness to direct palpation

- must compare to ensure other side is not tender

- may have bilateral ACJ OA)

 

Cross body adduction stress test

 

Shoulder cross body adduction

 

Chronopoulos et al. JBJS Am 2004

- 35 patients with isolated ACJ lesions

- cross body adduction stress test sensitivity of 77%

https://pubmed.ncbi.nlm.nih.gov/15090381/

 

Diagnosis

 

LA + Cortisone

- inject into joint

- diagnostic / therapeutic

 

DDx

 

Intrinsic

- shoulder impingement / rotator cuff tear / calcific tendonitis

 

Extrinsic

- cervical root C4/5

- shoulder tip pain from abdominal pathology

 

Xray

 

Zanca view

- AP 10° cephalic tilt with 50% penetration 

 

ACJ OA Inferior Clavicle Osteophyte

 

MRI

 

ACJ OA MRI

 

Stein et al. J Should Elbow Surg 2001

https://pubmed.ncbi.nlm.nih.gov/11408899/

 

Grade I: Normal

Grade II: Capsular distension, bone marrow oedema, mild joint narrowing

Grade III: Capsular distension, joint space narrowing, marginal osteophytes

Grade IV:  Markedly abnormal ACJ with large osteophytes

 

Bone Scan

 

ACJ OA Hot Bone ScanHot ACJ Bone Scan

 

Management

 

Issues

 

1.  Isolated ACJ pathology

 

2.  MRI diagnosed ACJ OA in the setting of rotator cuff tears

 

Wang et al. CORR 2018

- meta-analysis of distal clavicle resection in patients undergoing rotator cuff repair

- 3 RCTs with 208 patients

- no difference in outcome scores

https://pubmed.ncbi.nlm.nih.gov/30334833/

 

Non-operative

 

Most patients respond well

NSAIDs

Activity modification

Physiotherapy

Steroid injection

 

Operative

 

Indications for surgery

 

Isolated ACJ pathology

- x-ray and MRI evidence of degenerative change at ACJ

- tenderness at ACJ

- pain relieved by LA and cortisone injection to ACJ

- failure of non operative treatment

 

Aim

 

Resect sufficient distal clavicle to prevent abutment

 

Options

 

1.  Open excision distal clavicle resection

2.  Arthroscopic distal clavicle resection

 

Hohmann et al Arch Orthop Trauma Surg 2019

- systematic review of 4 studies and 319 patients

- no difference in outomes

https://pubmed.ncbi.nlm.nih.gov/30637505/

 

Open distal clavicle resection

 

Post Open ACJ Excision

 

Technique

- incision centered over the ACJ

- minimal takedown of deltopectoral fascia and anterior deltoid

- incise ACJ capsule longitudinally in midline

- elevate subperiosteally and repair later for stability

- resect 1 cm of distal clavicle only so as to not destabilise clavicle

- must leave conoid / trapezoid ligaments intact

 

Arthroscopic Distal Clavicle Resection

 

Snyder Vumedi Video

https://www.vumedi.com/video/arthroscopic-mumford-procedure-and-subacromial-decompression/

 

Advantage

- minimal incisions

- preserves superior AC ligament and deltoid

- low risk of infection

 

Disadvantage

- potential inadequate resection

- particularly superior and posterior

 

Technique

 

1.  Identify distal clavicle

- camera posterior portal, electrocautery lateral portal

- remove bursa in subacromial space

- follow anterior acromion medially with cautery

- identify the distal clavicle (push down on clavicle repetitively)

- clean and identify clavicle anterior and posterior

 

2.  Anterior portal

- placed just at lateral aspect of distal acromion

- in line with AC joint

- remove anterior then posterior clavicle

- must remove full thickness of distal clavicle superiorly / be able to visualise superior AC ligament

- must not leave posterior edge

- can place camera in lateral portal to enhance view

 

ACJ OA 3 Anterior CannulaACJ OA 3 Anterior cannulaACJ OA Debridement 1ACJ OA Debridement 2

Post Arthroscopic ACJ resection