AC Arthritis ICD-10
- 715.11 (osteoarthritis shoulder region, localized, primary)
AC Arthritis Etiology / Epidemiology / Natural History
- Repetitive overhead activity or throwing may lead to repeated microtrauma in the AC joint with susequant arthritis.
- May occur after Grade 1 AC separations.
AC Arthritis Anatomy
- Diarthrodial joint which contains a meniscus.
- Mutiple anatomic variations.
- Allows approximatley 40° to 50° of rotation.
- see also Shoulder Anatomy.
AC Arthritis Clinical Evaluation
- Pain isolated to AC joint. ACJ palpation reproduces symptoms.
- Aggravated by use of arm above shoulder level, or reaching behind the back or across chest
- Cross-body Adduction Test: arm is maximally adducted with the arm in 90 of forward elevation. Pain localized to the AC joint indicates AC joint patholgy.
- Adduction, IR and extension isolates posterior AC facet problems
- Tenderness to A/P translation
- AC joint pain with impingement maneuvers
- O’Brien test (arm adducted, 90 forward elevation, thumb-up position causing ACJ pain) (O’Brien SJ, AM J Sports Med 1998;26;610-613).
- have pt hold are straight in front at shoulder level, forced horizontal adduction/abduction causes AC pain
- Evaluate for hx of AC joint separation, generalized OA, weight lifting (distal clavicle osteolysis), repetitive stress (gymnastics).
- Differential injections in subacromial space and AC joint at different office visits
AC Arthritis Xray / Diagnositc Tests
- AP, scapular lateral and axillary views show spurring, sclerosis, osteophyte formation and narrowing of AC joint
- AC joint best viewed with a Zanca view of clavicle.
- Weighted views indicated if instability is a concern.
- AC joint local anesthetic and corticosteriod injection often indicated to confirm diagnosis. Relief of symptoms after injection confirms AC joint pathology as the cause of symptoms.
AC Arthritis Classification / Treatment
- Non-operative: NSAIDS, physical therapy, activity modifications, ACJ injections
- Operative: open vs arthroscopic distal clavicle resection generally considered only after failure of 3-6months of non-operative treatment.
- See Distal Clavicle Resection Technique
- Must ensure pain is secondary to arthritis and not instability. If there is AC instability Ca ligament reconstruction +/-DCR is indicated
- Open excision may be indicated for patients with hypertrophic osetoarthritis.
AC Arthritis Associated Injuries / Differential Diagnosis
AC Arthritis Complications
- Instability(excessive resection)
- Continued symptoms (inadequate resection)
- Ectopic calcification
- Reactive bursitis
- Clavicle/acromion fracture
AC Arthritis Follow-up Care
- 71% excellent, 16.5% good, 12.5% failure (Levine WN Arthroscopy 1998;14:52-6).
- Post-op: sling as needed with pendulum ROM exercises.
- 1 week: Start PT focused on ROM and strengthening. AAROM, PROM. AROM, free weights start at 3 weeks. Avoid cross-body adduction for 6 weeks.
- 6 weeks: progressive sport specific activity.
- 3 months: Return to sport / full activities.
- IF in association with SAD, or RTC repair use those rehab protocols.
- Outcome measures: ASES score, pain scales.
AC Arthritis Review References