Pain Where the Collarbone Meets the Breastbone (SC Joint)

Pain where the collarbone meets the breastbone usually comes from the sternoclavicular (SC) joint. The common causes are a sprain from a fall or a blow to the shoulder, and wear-related arthritis from middle age on. Most mild SC sprains settle over 2 to 6 weeks. A rare backward (posterior) dislocation can press on the windpipe, food pipe or large blood vessels behind the joint. With trouble breathing or swallowing, that is an emergency.

The SC joint sits at the base of the front of the neck, one on each side of the notch at the top of the breastbone. It is the one bony joint that links the arm to the trunk, so it moves a little every time you shrug, reach or lift your arm overhead.

Key takeaways

Where it hurts: at the inner end of the collarbone, beside the notch at the top of the breastbone.
Common causes: sprains after a fall or blow, and arthritis in middle age and later. Infection and inflammatory joint disease are less common causes.
Typical course: mild sprains often settle in 2 to 6 weeks; more severe ligament injuries often take 6 to 12 weeks.
Forward dislocation: the more common type, leaving a visible bump, and usually managed without surgery.
Backward dislocation: rare, and an emergency if it causes trouble breathing, swallowing or a change in voice.

Where are you right now?

Just injured: read the emergency section first, then “Week by week”.
Weeks in and not settling: go to “If it isn’t going to plan”.
After an injection or surgery: injections are sometimes used for SC joint arthritis, and surgery is uncommon. Follow the plan from the doctor who treated you.
Getting back to work or sport: the “When can I…” table gives typical ranges.

Week by week

These stages describe a sprain, the most common SC joint injury. The SC joint is one of four joints that make up the shoulder complex, so most arm movements load it.

Days 0 to 7: pain at the joint with shrugging, reaching across the body and lying on that side. A sling for a few days may help if your doctor advises it. Cold packs can ease swelling.
Weeks 1 to 3: gentle movement with the arm below shoulder height. Avoid carrying heavy bags on that side, push-ups and reaching across the body.
Weeks 3 to 6: most mild sprains are much easier. Strengthening for the shoulder blade muscles usually starts.
Weeks 6 to 12: more severe sprains and forward dislocations keep improving. Pushing, overhead lifting and contact sport return gradually.
With arthritis: flares often settle over 2 to 6 weeks with fewer aggravating loads. A firm bump at the joint usually stays.

Where else this could be coming from

Broken collarbone: a broken collarbone is tender on the bone itself, usually along the middle. In teenagers and young adults, a break near the inner end can look like an SC dislocation, because the growth plate there is one of the last in the body to close, often not until the early to mid 20s.
The other end of the collarbone: a separated shoulder (AC joint sprain) hurts on top of the shoulder, at the outer end of the collarbone.
Costochondritis: irritation where the rib cartilages join the breastbone. The tender spots sit lower, beside the breastbone, usually around the second to fifth ribs.
Thoracic outlet syndrome: pressure on the nerves or vessels near the collarbone causes tingling, heaviness or color change in the arm with certain arm positions, rather than pain at one joint.
The heart: pain behind the breastbone with exertion, breathlessness or sweating can be heart-related, and it is not tender to press.

A small joint at the base of the neck carries the whole arm, every time you reach.

Is this normal?

“There is a bump that was not there before.” After a forward dislocation, or with arthritis, a bump often stays. It rarely affects how the arm works.
“It clicks when I lift my arm.” Clicking at the joint is common after a sprain and often becomes painless over time.
“It aches when I take a deep breath.” The breastbone and rib joints move as you breathe, so a mild ache can happen early on. Breathlessness is different, and belongs in the safety sections below.
“The two sides look different.” Mild differences between the two SC joints are common, especially in people who use one arm much more.

If it isn’t going to plan

It is week five. Carrying the grocery bag on that side still sends a sharp twinge to the base of your neck, and you feel it every time you reach for the seatbelt. The thought in your head is that it is such a small joint, it should have healed by now.

Small does not mean lightly loaded. The SC joint moves with nearly every arm movement, all day, so it rarely gets true rest. Ligaments also heal slowly, often over 6 to 12 weeks. Resting the arm calms pain for a while, but the joint is loaded again the moment you reach.

What a sore SC joint needs is less strain per movement: fewer heavy loads on that side for a while, and stronger shoulder blade muscles so the collarbone is not dragged forward with each reach. With arthritis, the same approach applies over a longer period.

If you are 6 weeks in and not clearly easing, get assessed by a doctor or a physical therapist. Ask:

Cause: is this a sprain, a loose joint or arthritis?
Imaging: would a scan help? A CT scan is often used because this joint is hard to see on a plain X-ray.
Stability: does the joint move more than it should?
Load: which tasks should I reduce for now, and which exercises should I start?

When can I…

Activity	Typical range
Sleep on that side	Often 2 to 6 weeks after an SC joint sprain
Drive	Often within 1 to 2 weeks, once you can turn the wheel and look over your shoulder
Reach overhead	Often 2 to 6 weeks
Lift	Light items within 1 to 2 weeks; heavy lifting or carrying on that side often 6 to 12 weeks
Desk work	Often within a few days
Manual work or sport	Often 6 to 12 weeks; contact sport after a dislocation often 3 months or longer

If you have had surgery, your surgeon’s protocol comes first.

Call your local emergency number or go to the emergency department if

Breathing or swallowing: trouble breathing, trouble swallowing, choking or a hoarse voice after a blow to the shoulder or chest.
A hollow at the joint: a dip where the inner end of the collarbone should be, after an injury.
Arm circulation: the arm swells, turns blue or pale, or goes cold or numb after an injury.
Chest symptoms: chest pain or pressure with breathlessness, sweating or nausea.

See a doctor today if

Hot, swollen joint: the joint is red, hot and swollen, especially with fever or feeling unwell.
A new bump after an injury: a bump at the joint with severe pain after a fall or blow.
Cannot use the arm: pain stops you moving the arm after an injury.

Get it checked soon if

Swelling without injury: the joint has swollen with no injury and it lasts more than 2 weeks.
No change: pain is not clearly easing after about 6 weeks.
Slipping: the joint feels as if it shifts out and back with arm movement.
Other joints: both SC joints or several other joints are swollen, with morning stiffness.