The acromioclavicular (AC) joint is the small joint at the top of the shoulder where the collarbone (clavicle) meets the shoulder blade (acromion). Two common problems cause pain here: AC joint arthritis, wear of the joint cartilage that becomes more common with age or after an old AC separation, and distal clavicle osteolysis, a stress injury to the end of the collarbone seen mainly in weightlifters. Dr. Andrew Dold, a board-certified, fellowship-trained sports medicine surgeon in Frisco, Texas, treats both, starting with non-surgical care and, when needed, arthroscopic distal clavicle excision.
- Pain is felt on top of the shoulder and is worse reaching across the body, lifting overhead or bench pressing
- Activity changes, anti-inflammatory medicine and an injection into the joint help many patients
- An injection of numbing medicine also helps confirm that the AC joint is the source of pain
- For pain that persists, a small portion of the end of the collarbone can be removed arthroscopically
Causes
- Wear and tear (osteoarthritis): the cartilage gradually thins, and bone spurs can form
- Previous injury: an earlier AC joint separation or fracture near the joint can lead to arthritis later
- Distal clavicle osteolysis: repeated heavy loading, especially bench press, dips and overhead lifting, causes tiny stress fractures and bone breakdown at the end of the collarbone. It was first reported as a series in weight trainers in 1982.1
Symptoms
- Pain directly on top of the shoulder, which you can often point to with one finger
- Pain reaching across the body, such as fastening a seat belt or washing the opposite armpit
- Pain with bench press, push-ups, dips or overhead lifting
- Pain lying on the affected shoulder
- A bump or swelling over the joint
Diagnosis
Dr. Dold checks for tenderness over the AC joint and pain when the arm is brought across the body, and examines the rotator cuff and biceps, which often cause pain at the same time. X-rays show narrowing, spurs or bone loss at the end of the collarbone. An MRI may show swelling in the bone (common in osteolysis) and other shoulder problems.1 A diagnostic injection of numbing medicine into the AC joint can confirm the source of pain: if the pain goes away, the AC joint is the likely cause.
Treatment without surgery
- Activity changes: avoid or modify the painful lifts for a period, for example by narrowing the bench-press grip, limiting depth or switching exercises
- Ice and anti-inflammatory medicine, if safe for you
- Physical therapy to strengthen the shoulder and shoulder-blade muscles
- A cortisone injection into the AC joint to reduce pain
For osteolysis, avoiding the provocative movements, modifying weight-training technique, ice and anti-inflammatory medicine form the basis of initial treatment.1
Surgery: distal clavicle excision
When pain persists despite non-surgical treatment and the AC joint is confirmed as the source, Dr. Dold may recommend a distal clavicle excision: a small portion of the end of the collarbone is removed so the bones no longer rub, while the ligaments that keep the collarbone stable are preserved. It can be done arthroscopically through small incisions, and it can be combined with other procedures such as a rotator cuff repair.
In a systematic review of 17 studies, arthroscopic distal clavicle excision had success rates over 90%, more good or excellent outcomes than the open procedure and a faster return to activities, with similar long-term results. Results were less predictable when the joint was unstable from a previous injury.2
Recovery
After arthroscopic distal clavicle excision, most patients use a sling briefly for comfort and start moving the shoulder early, then progress with strengthening. Heavy pressing and overhead lifting are resumed gradually over the following months. Dr. Dold will give you a specific plan.
Why see Dr. Dold
- Board certified by the American Board of Orthopaedic Surgery, with subspecialty certification in Sports Medicine
- Sports medicine and arthroscopy fellowship at NYU Langone / Hospital for Joint Diseases; orthopedic residency at the University of Toronto
- Fellow of the American College of Surgeons (FACS), the American Academy of Orthopaedic Surgeons (FAAOS), the American Orthopaedic Association (FAOA) and the Royal College of Surgeons of Canada (FRCSC)
- Author of a SLAP repair book chapter (Springer, 2017) and research on shoulder suture anchors (KSSTA, 2013)
- Team physician and surgical consultant to Rugby Canada; has cared for professional athletes from the NFL, NBA, NHL, MLS, PGA Tour and Major League Rugby
- D Magazine Best Doctors (Collin County), 2019–2026 · Rated 4.9 on Google
Frequently asked questions
What is the difference between an AC separation and AC arthritis?
An AC separation is a ligament injury, usually from a fall. AC arthritis is wear of the joint cartilage, which can develop over time or after an old separation.
Why does my shoulder hurt when I bench press?
Bench press, dips and push-ups load the AC joint heavily. In weightlifters, this can cause distal clavicle osteolysis, a stress injury to the end of the collarbone.1
Will I have to stop lifting?
Usually not permanently. Modifying the painful lifts for a period, along with ice and anti-inflammatory medicine, is the first step.1
Does removing the end of the collarbone weaken the shoulder?
Only a small portion of bone is removed and the stabilizing ligaments are preserved. Success rates over 90% have been reported after arthroscopic excision.2
How long is recovery?
Most patients start moving the shoulder early after arthroscopic excision, with a gradual return to heavy lifting over the following months.
Do you accept my insurance?
Dr. Dold accepts most major insurance plans, including Medicare and Tricare. Please call 469-850-0680 to confirm your coverage.
Research cited on this page
- Schwarzkopf R, Ishak C, Elman M, et al. Distal clavicular osteolysis: a review of the literature. Bull NYU Hosp Jt Dis. 2008;66(2):94-101. PubMed
- Pensak M, Grumet RC, Slabaugh MA, et al. Open versus arthroscopic distal clavicle resection. Arthroscopy. 2010;26(5):697-704. PubMed
Medically reviewed by Andrew P. Dold, MD, FAOA, FAAOS, FACS, FRCSC. This page is general information, not medical advice. Individual results vary.
