Clavicle and acromioclavicular joint

«I came off my bike and now there is a lump on top of my shoulder»

A lump or pain at the top of the shoulder after a fall, typical in cycling and contact sports. When it is treated without surgery and when operating helps.

Book a consultation See treatments

Treated by Dr. Ricardo Aveledo, shoulder subspecialist certified by the Royal College of Surgeons. Consultation and surgery in Tenerife · Hospital Quirónsalud View CV

Do any of these sound familiar?

If two or three sound familiar, this fits the picture.

A visible lump or step at the top of the shoulder
Pain localised right on top, not deep inside the joint
Pain when bringing the arm across the chest
Discomfort sleeping on that side or carrying a rucksack
Pain doing dips, bench press or press-ups
A sense of instability or of something moving when you press on it

Worth having it assessed soon if you also notice

Skin over the lump that is tight, white or about to break: the clavicle may be threatening the skin and needs urgent assessment.
Tingling or loss of strength in the arm or hand.
Difficulty breathing after the injury: go to A&E.

The acromioclavicular joint links the end of the clavicle to the acromion, at the top of the shoulder. It is what gets injured in falls onto the shoulder.

Two different injuries in the same place

Pain at the top of the shoulder after a fall usually means one of two things, and although they hurt in the same place they are not the same.

A clavicle fracture is the bone broken, almost always in its middle third. It is one of the commonest fractures in the human body and the classic cycling injury: fall onto the shoulder, immediate pain and often an obvious lump.

An acromioclavicular dislocation is separation of the joint where the clavicle meets the acromion. The bone is intact, but the ligaments holding it down have torn, and the clavicle is left raised. This produces the very characteristic step at the top of the shoulder.

The grades of acromioclavicular dislocation

The classification is not a technicality: it directly determines whether surgery is used.

Grades I and II. The ligaments are stretched or partially torn. There is barely a step. Conservative treatment, with very good results.

Grade III. Complete tear of the coracoclavicular ligaments, with an obvious step. This is the grade that generates most debate. Most are treated without surgery with a good functional result, and surgery is considered in athletes, manual workers, or where the conservative result is unsatisfactory.

Grades IV, V and VI. Severe displacement, with the clavicle displaced backwards, markedly raised, or locked under the coracoid. Here surgery is the usual indication.

A technique Dr. Aveledo has published on

Reconstruction of the acromioclavicular joint is one of Dr. Aveledo’s lines of work. He is first author of Independent Arthroscopic-Assisted Acromioclavicular Ligament Reconstruction: A Novel Technique, published in Techniques in Shoulder & Elbow Surgery in 2019, and co-author of a biomechanical study of the same repair published in Shoulder & Elbow in 2020.

The underlying idea of that technique is to reconstruct the acromioclavicular ligaments independently as well as the coracoclavicular ones, to give better control of horizontal stability — backward displacement of the clavicle — which is one of the known causes of residual pain when only vertical stability is reconstructed.

How the diagnosis is confirmed

01
Examination and palpation

The exact site of pain and the characteristic step are usually enough to point to the diagnosis, and to grade the separation of the joint.
02
X-ray

Confirms whether there is a clavicle fracture and how displaced it is, or whether this is an acromioclavicular dislocation. Sometimes taken holding a weight to grade it better.
03
Grading

In acromioclavicular dislocation the grade (I to VI) directly determines treatment: low grades are not operated on and high grades almost always are.

What can be done, and in what order

Surgery is not the starting point. It is proposed when it beats not operating, and the reasoning is explained.

First option

Treatment without surgery

This resolves most minimally displaced clavicle fractures and low-grade acromioclavicular dislocations. The step may remain, but the shoulder works.

When: A minimally displaced clavicle fracture, or a grade I to III acromioclavicular dislocation in someone without high shoulder demand.

What it involves

Sling for several weeks, with no need for figure-of-eight bandages, which have shown no advantage
Early movement of the elbow and hand, and of the shoulder as soon as pain allows
Progressive physiotherapy to restore the scapulohumeral rhythm
X-ray checks in fractures, to confirm union is progressing

If needed

Surgery

Either the bone is stabilised or the ligaments holding the clavicle in place are reconstructed.

When: Markedly displaced or shortened fractures, or fractures threatening the skin; grade IV to VI dislocations; and grade III in athletes or manual workers.

What it involves

Clavicle fixation with an anatomical plate and screws, in markedly displaced or shortened fractures
Reconstruction of the coracoclavicular ligaments in high-grade dislocations
Arthroscopically assisted independent ligament reconstruction, a technique Dr. Aveledo has published on in Techniques in Shoulder & Elbow Surgery
Simultaneous arthroscopic assessment of the joint, which allows associated injuries to be found

How long will this take?

These timings correspond to clavicle fixation or ligament reconstruction. With conservative treatment, union times are similar. These are approximate ranges.

Wk 0–4

Wk 4–10

Wk 10–16

Wk 16–24

Protection First 4 weeks

Sling. Elbow and hand movement from day one, and shoulder movement below horizontal as tolerated.
Full movement Weeks 4–10

The sling is discarded and full range is regained. Return to driving and desk work, usually between weeks three and six.
Strength Weeks 10–16

Progressive strengthening, including overhead loading. Staged return to the gym.
Contact sport and cycling Weeks 16–24

Sports with a risk of falling onto the shoulder, once union is complete and strength restored.

Frequently asked questions

I have been left with a lump — will it go?

If it is an acromioclavicular dislocation treated without surgery, the step usually stays: the clavicle remains slightly raised. It is a cosmetic matter more than a functional one, because most of these shoulders work normally and without pain. If the lump is bony callus from a healed fracture, it tends to remodel and shrink over the months.

Does a broken clavicle need surgery?

Most do not. Surgery is used where displacement is large, where there is significant shortening, where the skin is threatened, where the fracture has several fragments, or where it fails to unite. In all other cases healing without surgery is the norm.

Can I get back on the bike?

Yes. Indoor turbo training resumes early, as soon as pain allows and you can hold the bars comfortably. Road riding, with the risk of falling it involves, waits until union is complete, at around three months.

Does the plate have to come out afterwards?

Not routinely. It is removed if it is troublesome, and the clavicle is a very superficial bone, so it is not unusual for a plate to be uncomfortable under a rucksack or a seatbelt. If it is removed, that is usually after a year, once union is complete.

What exactly is the acromioclavicular joint?

It is the small joint where the outer end of the clavicle meets the acromion, at the very top of the shoulder. Short, very strong ligaments hold it. When you fall sideways onto the shoulder, those ligaments absorb the blow, and if they tear the clavicle is left raised relative to the acromion: that is the step you can see and feel.

Often confused with

An assessment with Dr. Aveledo

Consultations at Hospital Quirónsalud Tenerife, Vida Puerto de la Cruz and Quirónsalud Santa Cruz.

Book a consultation Take the shoulder test