How Does a Broken Collarbone Heal, Week by Week

A broken collarbone follows a predictable biological repair sequence that unfolds over months, not weeks. Your body begins patching the break within hours of the injury, but full bone union for a midshaft clavicle fracture treated without surgery typically takes somewhere between 18 and 28 weeks.¹ That timeline surprises most people, who assume the sling comes off at six weeks and everything is back to normal. The reality is messier and more interesting, with distinct biological stages that each accomplish something different.

The First Few Days

Within minutes of the fracture, blood pools at the break site and forms a clot called a hematoma. This is not just incidental bleeding. The hematoma coagulates and forms a temporary scaffold that acts as a template for new bone formation.² Think of it as a rough framework that tells the repair cells where to go and what shape to build. The acute inflammatory response that drives this stage peaks in the first few days. Swelling, warmth, and throbbing pain are signs that your body is flooding the area with immune cells and signaling molecules to clean up damaged tissue and recruit the cells that will actually rebuild bone.

This is the phase where pain is at its worst. You are typically in a sling, and every small movement of the shoulder or arm reminds you the bone is broken. Sleeping is difficult because there is no comfortable position. Ice, over-the-counter pain relief, and keeping the arm immobilized are the main strategies. The good news is that this acute inflammation settles substantially within the first week, and each day is usually a little better than the last.

Weeks 2 and 3

Once the initial inflammation calms down, your body starts building a soft callus around the break. This is a rubbery mass of cartilage and new blood vessels that bridges the gap between the broken ends. It does not feel like bone yet. If you could see it on an X-ray at this point, it would look like a hazy cloud around the fracture. The soft callus is mechanically weak, which is why you still need the sling and should avoid lifting or reaching with the injured arm.³

Pain at this stage is noticeably less than during the first week. Many people describe it as a deep ache rather than sharp pain, and they start sleeping better. You can usually move your fingers, wrist, and elbow freely, and your doctor will encourage gentle pendulum exercises at the shoulder to prevent stiffness. But the break itself is still fragile. A fall or sudden jerk to the arm during this window can disrupt the soft callus and set healing back.

Weeks 4 Through 6

The soft cartilage callus gradually mineralizes and gets replaced by woven bone, a preliminary type of bone tissue that is stiffer than cartilage but not yet as organized or strong as mature bone. As this hard callus formation progresses and calcified cartilage gives way to woven bone, the fracture site becomes more solid and mechanically rigid.⁴ You can feel this happening in a literal sense: the bump over the fracture, which was soft and tender at first, starts feeling harder and less painful to the touch.

Around this time, many people begin weaning off the sling. Your doctor or physiotherapist may clear you for active range-of-motion exercises at the shoulder and light daily tasks. The fracture is far from healed, but it is stable enough that normal gentle use of the arm will not undo the repair. Lifting anything heavy, sports, and impact activities are still off-limits. The woven bone is strong enough to resist everyday forces but not strong enough for sudden loads.

Weeks 6 Through 12

This is the period most people think of as “healing.” The woven bone continues to solidify, and X-rays start showing a visible bridge of new bone across the fracture gap. In clinical terms, the fracture is approaching what surgeons call “union,” the point where the bone can bear normal loads without risk of re-fracture. For straightforward midshaft breaks, this is when many patients feel functionally normal for everyday tasks and begin guided strengthening exercises.

But the full picture is more conservative than patients expect. Research on nonoperatively managed midshaft clavicle fractures puts actual bony union at 18 to 28 weeks after the injury.¹ That means even at 12 weeks the bone is not truly finished healing. You may feel fine, and the fracture may look good on imaging, but the internal remodeling that turns temporary woven bone into the real thing is still underway. Pushing hard into contact sports or heavy overhead work before 12 weeks carries genuine risk.

Beyond Week 12

The final phase of healing, called remodeling, is the longest and the least visible. Your body slowly tears down the bulky woven bone callus and replaces it with organized lamellar bone, the strong, layered bone tissue that makes up a healthy adult skeleton. This process is driven by the coordinated activity of bone-building cells and bone-resorbing cells working in tandem over a span of several months.⁵

You will not feel this remodeling. By this point, most people have returned to their full range of activities. But if you run your fingers along the collarbone, you will probably still feel a noticeable bump where the fracture was. That bump is the remnant of the hard callus. Over the following months and even into the next year, remodeling gradually reshapes it. In adults, the bump often shrinks but never completely disappears. In children and teenagers, whose bones are still growing, the remodeling process is more aggressive and the bump tends to flatten more completely.

That Bump on the Collarbone

The hard lump that forms at the fracture site worries a lot of people. It can be quite prominent, especially if the broken ends were displaced or overlapping. The bump is made of callus tissue, the same woven bone your body built to bridge the gap. It is not a sign that something went wrong. It is actually a sign that healing is proceeding normally. The more displaced the fracture, the more callus the body produces, and the bigger the bump.

During the remodeling phase, the bump slowly shrinks as woven bone gets replaced by lamellar bone that better matches the original contour of the clavicle.⁵ In younger patients, the result can be nearly invisible after a year or two. In adults over 30, a permanent palpable ridge is common. It is cosmetic, not functional, and it does not affect the strength of the healed bone. If the appearance bothers you, that is worth discussing with your surgeon, but from a healing standpoint the bump means the bone did its job.

What Slows Healing Down

Not every collarbone fracture follows the textbook timeline. Some breaks heal quickly and uneventfully, while others drag on or fail to unite altogether. A study examining risk factors for nonunion in conservatively managed midshaft clavicle fractures found three independent predictors: smoking, fracture displacement, and comminution (the fracture being shattered into multiple fragments rather than a clean break).⁶ Among those, the severity of displacement was the strongest risk factor, and smoking roughly quadrupled the odds of the fracture failing to heal.

The smoking effect is something surgeons consistently emphasize. Nicotine constricts blood vessels and reduces blood flow to the fracture site, starving the healing cells of oxygen and nutrients right when they need them most. If you smoke and break your collarbone, quitting or at least pausing during the healing window is one of the most impactful things you can do. Vaping nicotine likely has a similar effect, though the research specifically on vaping and fracture healing is thinner.

Other factors that influence the pace of healing include age, nutrition, and whether you have underlying conditions like diabetes or osteoporosis. Younger patients heal faster because their bone turnover is naturally higher. Adequate protein and calcium intake supports callus formation, though mega-dosing supplements has not been shown to speed things up. And certain medications, particularly long-term corticosteroids and some anti-inflammatory drugs, can interfere with the inflammatory phase that kicks off the whole repair cascade.²

When Surgery Becomes Part of the Picture

Most clavicle fractures are treated without surgery. A sling, pain management, and time are enough for the vast majority of midshaft breaks. But certain fracture patterns push the equation toward surgical fixation with a plate and screws or an intramedullary nail. Severely displaced breaks, where the two ends are not in contact with each other at all, have a harder time healing on their own because the hematoma scaffold cannot bridge a wide gap effectively. Fractures with significant comminution also carry higher nonunion risk.⁶

Fractures near the outer end of the collarbone, close to the shoulder joint, are a separate category. These so-called lateral or distal clavicle fractures behave differently from midshaft ones because of how the ligaments attach in that area. They tend to have higher nonunion rates with conservative treatment, and surgeons are more inclined to operate. If your break is in this zone, the week-by-week healing pattern is similar biologically, but the clinical timeline and treatment recommendations may differ.

When surgery is performed, the biological healing phases remain the same. The bone still goes through inflammation, soft callus, hard callus, and remodeling. What the plate does is hold the broken ends in perfect alignment, allowing the repair to proceed with less callus bulk and better mechanical stability from day one. Surgically fixed fractures often allow earlier return to motion, but the bone itself is not healed faster. You still need to respect the biological clock.

Returning to Sports and Physical Work

This is the question that matters most to many patients, and the honest answer is that it depends on the sport. Light aerobic activities like walking and stationary cycling can usually resume within a few weeks, since they place no direct load on the collarbone. Swimming, which involves repetitive overhead motion and water resistance against the arm, typically waits until around 8 to 10 weeks or until you have full pain-free range of motion. Contact sports and overhead strength work are the last to return, often not cleared until 12 weeks at the earliest, and sometimes longer if healing has been slow.

The tricky part is that how you feel is an unreliable guide. The collarbone can feel fine for daily tasks while still being at risk for re-fracture under high loads. Imaging and a clinical exam by your surgeon or physiotherapist are better indicators than pain levels. If you are cleared to return based on imaging showing solid callus and you have regained full strength and range of motion, re-fracture rates are low. Jumping back early because the sling is annoying and you feel “pretty good” is how people end up back at the start of the timeline.

For manual laborers, return to full duties follows a similar logic. Light desk work can resume within a week or two of the injury for most people. Jobs involving lifting, climbing, or overhead reaching require a longer wait, typically 8 to 12 weeks, and sometimes more depending on the demands of the job and the severity of the fracture. Having a conversation with your employer about modified duties during healing is usually more productive than trying to tough it out and risking a setback.

Nonunion and What It Means

A fracture that has not healed after six months is generally classified as a nonunion. This does not mean the bone stopped trying to heal. It means the repair process stalled somewhere along the way, usually during the transition from soft callus to hard callus, and the gap between the ends remains filled with fibrous tissue rather than bone. Nonunion of the clavicle is not common overall, but it is more frequent in displaced, comminuted fractures in adult smokers.⁶

Nonunion is typically painful. You feel an ongoing ache or a grating sensation at the fracture site when you move the arm, even months after the injury. If X-rays confirm that the gap has not closed and the bone ends have started to round off rather than bridging, surgery is usually recommended. The procedure involves freshening the bone ends, adding bone graft, and fixing the fracture with a plate. Outcomes from nonunion surgery are generally good, but the total recovery timeline resets and adds several more months.

Recognizing nonunion early matters. If you are at four or five months after a clavicle fracture and still having significant pain with use of the arm, that warrants imaging and a specialist opinion. Waiting passively beyond six months does not improve the odds of spontaneous union and can make the eventual surgery more complex.

Why Children Heal Faster

Clavicle fractures are common in children, often from playground falls or sports collisions. The healing timeline in kids is dramatically faster than in adults. A school-age child’s collarbone fracture may be clinically stable in three to four weeks and fully remodeled within a few months. The reason is that a child’s periosteum, the fibrous membrane wrapping the bone, is thicker and more metabolically active than an adult’s. It produces callus more rapidly and in greater volume relative to the size of the bone. Children also have the advantage of active skeletal growth, which drives the remodeling phase harder and reshapes the callus more completely.

Parents often worry about the large bump that forms at the fracture site in a child’s collarbone. In a five-year-old, that bump can look alarming, as if the bone healed crooked. But in nearly all cases, the bump remodels away over the following year or two, leaving little or no visible trace. The younger the child, the more completely the body erases the evidence. By adolescence, the remodeling capacity begins to slow, and healing timelines start to approach adult ranges. A sixteen-year-old’s clavicle fracture behaves more like an adult’s than a six-year-old’s.

1
PubMed Central. Nonoperative Treatment of Midshaft Clavicle Fractures in Adults
2
PubMed Central. Bone Healing and Inflammation: Principles of Fracture and Repair
3
NCBI Bookshelf. Fracture Healing Overview
4
PubMed Central. THE BIOLOGY OF FRACTURE HEALING – Section: Mineralization and Resorption of the Cartilaginous Callus
5
ScienceDirect. Bone fracture healing in mechanobiological modeling: A review of principles and methods – Section: 2. Biology of Bone Healing
6
Elsevier Masson SAS. Intrinsic and extrinsic risk factors for nonunion after nonoperative treatment of midshaft clavicle fractures