Acromioclavicular osteoarthritis -Quick review card

ACROMIOCLAVICULAR OSTEOARTHRITIS is acommon and potentially debilitating shoulder condition most common disorder of the AC joint seen in middle aged individuals ( more common with age ) more commonly in males common in weight lifters ( weight lifters shoulder ) can be (1 ) primary ie no underlying cause (2 ) secondary which is associated with an underlying cause as Rh arthritis AC joint arthritis can happen due to
○ degeneration of the intra-articular disc ○ post-traumatic arthropathy ○ distal clavicle osteolysis ○ inflammatory arthropathy ○ septic arthritis ( rare ) ○ joint instability ○ impingement repeated microtrauma can also cause AC jt OA often overlooked AC jt OA can cause subacromial impingement , hence can be associated with RC lesions and subacromial bursal inflammation risk factors for AC jt OA include age , h/o IV drug use (haematogenous seeding ) , past surgery , prior jt disease , intra-articular inj , rheumatoid arthritis , diabetes , immune deficiency , alcoholism & sickle cell anaemia

anterior and superior shoulder pain pain and limitations involving overhead and cross body movements / occupational activities pain -when lying on the affected shoulder made worse by pressing motion ( e,g bench press , push ups ) popping , clicking , grinding or catching sensation on movement presentation can also be with non-specific complaints of pain located in the neck , shoulder and / or arm local tenderness on palpation – not specific for condition ( low specificity ) , distal clavicle prominence

often an incidental finding in an asymptomatic patient on XR / MRI plain radiograph ( first line )
○ normal AP views / Zanca view
○ findings consistent with degenerative disease include sclerosis , osteophytes , subchondral cysts & joint space narrowing
○ XR changes can also be seen in normal people ie radiological prevalence is very common & can reach 90 % in asymptomatic people > 30 Ultrasound/ CT/ MRI ( specialist options ) XR/ MRI provide best information of AC jt anatomy / pathology.

diagnosis can be challenging differentiating from other conditions which can lead to similar symptoms can be difficult 
○ cervical spine disorders| ○ symptomatic os acromiale○ rotator cuff injury ○ subacromial impingement diagnosis is made on basis of history , clinical examination and some specific tests (cross arm test, O’Brien test ) and diagnostic LA injection ( LA inj into the AC jt should ease symptoms ) and can also be therapeutic
○ inj’s are difficult to perform and US guidance can improve the chances of reaching the intra-articular space
○ a lack of response suggests an alternative diagnosis.

Management – oral analgesics activity modification & physical therapy ( 1st line )
- refer for physiotherapy immobilization corticosteroid injection and local anaesthetic- can provide good short term relief and act as helpful diagnostic test but long term benefit is not seen

most cases can be managed conservatively surgical treatment is considered when conservative management fails and patient has continued pain / loss of shoulder function distal clavicular excision ( DCE ) open / arthorscopic most common complication of surgical intervention is persistent pain due to over or under – resection.

REFERENCES

1. Compagnoni, Riccardo et al. “Management of Acromioclavicular Osteoarthritis in Rotator Cuff Tears: A Scoping Review.” Joints vol. 7,4 199-204. 14 Jun. 2021, doi:10.1055/s-0041-1730378
2. Mall NA, Foley E, Chalmers PN, Cole BJ, Romeo AA, Bach BR. Degenerative Joint Disease of the Acromioclavicular Joint: A Review. The American Journal of Sports Medicine. 2013;41(11):2684-2692. doi:10.1177/0363546513485359
3. Precerutti, Matteo et al. “Acromioclavicular osteoarthritis and shoulder pain: a review of the role of ultrasonography.” Journal of ultrasound vol. 23,3 (2020): 317-325. doi:10.1007/s40477-020-00498-z
4. Chaudhury, Salma et al. “Managing acromio-clavicular joint pain: a scoping review.” Shoulder & elbow vol. 10,1 (2018): 4-14. doi:10.1177/1758573217700839
5. Menge TJ, Boykin RE, Bushnell BD, Byram IR. Acromioclavicular osteoarthritis: a common cause of shoulder pain. South Med J. 2014 May;107(5):324-9. doi: 10.1097/SMJ.0000000000000101. PMID: 24937735. ( Abstract )