Written by Shamaine Soh, Principal Hand Occupational Therapist at Phoenix Rehab, AHPC A1302343D.Clinically reviewed by Nigel Chua, Principal Hand Occupational Therapist & Director, AHPC A1300362Z.Last reviewed 7 October 2026.
A distal biceps rupture is the biceps tendon torn off the radius, the forearm bone, just below the elbow crease, usually when a heavy load forces a bent elbow straight. Most people feel a pop, then see bruising at the front of the elbow and find turning the palm up weak. See a doctor the same day.
Key takeaways
- A distal biceps rupture is the biceps tendon torn off the radius just below the elbow crease. It usually happens when a heavy load forces a bent elbow straight.
- The usual signs are a pop, bruising at the front of the elbow and forearm, the biceps bunched up toward the shoulder, and weakness turning the palm up.
- The elbow often still bends, because the brachialis muscle underneath bends it too. Turning the palm up is the movement that gives the tear away.
- Surgeons find the tendon easier to reattach early. After about 2 weeks it tends to scar and pull back up the arm.
- A doctor confirms the tear and decides on a scan, and a surgeon decides on the repair. After a repair, a hand therapist runs the brace, the protected movement and the strength work to your surgeon’s protocol.
What is a distal biceps rupture?
The biceps starts as two heads at the shoulder and ends as one tendon at the elbow. That tendon dives into the front of the elbow crease and attaches to a bump on the radius, the forearm bone on the thumb side. Its main jobs are turning the palm up, which doctors call supination, and helping to bend the elbow.
A second muscle, the brachialis, sits under the biceps and bends the elbow whichever way the palm faces. So when the biceps tendon comes off the bone, you can usually still bend the elbow. Turning a screwdriver, a door knob or a key is where the weakness shows.
The reverse Popeye sign
With the tendon gone from the radius, the muscle belly pulls up toward the shoulder. The front of the upper arm can look hollow just above the elbow, with the biceps bunched higher than on the other arm. A tear at the shoulder end does the opposite: the bulge drops low in the arm, the Popeye sign. A sheet of tissue from the tendon to the forearm, the bicipital aponeurosis, can hold the muscle down even when the tendon is off, so a small change in shape does not rule a tear out.
Complete and partial tears
In a complete tear the whole tendon has come off the bone. In a partial tear some fibers still hold. A partial tear often shows as an ache at the front of the elbow and pain or weakness turning the palm up, with no pop and no change in shape. A surgeon decides whether a partial tear is protected and loaded back in stages or repaired.
How it happens, in the order to check
1. Catching or stopping something heavy
A box slipping off the top of a stack. The end of a sofa as the person on the other end lets go. A gas cylinder tipping. The biceps is working hard to hold the elbow bent, and the load forces it straight.
2. Lowering a heavy weight in the gym
The slow lowering of a heavy curl. The underhand arm of a mixed-grip deadlift. A failed muscle-up or a rope climb. See gym injuries and CrossFit injuries.
3. Lifting at work with the elbow bent
A sack of cement, a pallet corner, a toolbox lifted from the van floor. The same mechanism, often on a working day when the arm was already tired.
Distal biceps tears happen mostly in men in their 30s to 50s, usually in the dominant arm.2 Most people remember the exact moment.
The hook test
Doctors use the hook test to check whether the tendon is still attached. O’Driscoll and colleagues described it in 2007.1 You can try a gentle version once at home, so you know what to ask about. Skip it if the elbow looks out of place or the forearm is swelling fast.
- Sit with the injured elbow bent to a right angle, resting on a table, palm turned up.
- Tighten the biceps a little, as if starting to turn a key palm up.
- With the index finger of your other hand, come in from the outer side of the elbow crease, the thumb side, and try to hook the finger under a firm cord running down into the crease.
- Do the same on the other arm, so you know what normal feels like for you.
On a healthy arm you can hook a finger under the tendon like a bowstring. If there is no cord to hook from the outer side, the tendon may have come off the bone. Doctors hook from the outer side.1 From the inner side you can catch the aponeurosis instead and mistake it for the tendon. If hooking the cord hurts, that can point to a partial tear.
The test gives you a clue, and a doctor should confirm it. Whether you need an ultrasound or an MRI is a decision for your doctor.
Distal biceps rupture, long head rupture, brachialis strain, tennis elbow, golfer’s elbow or UCL sprain?
Ask three things: how it started, where it hurts, and whether turning the palm up is weak.
| Condition | How it started | Where you feel it | Turning the palm up | What it needs first |
|---|---|---|---|---|
| Distal biceps rupture | One moment: a heavy load forcing a bent elbow straight, often with a pop | Front of the elbow crease, with bruising into the forearm. The biceps bunches up toward the shoulder | Weak and painful | A doctor the same day. A surgeon decides on repair |
| Long head biceps rupture (at the shoulder) | A pop at the front of the shoulder lifting, often in older adults | Front of the shoulder, bruising down the upper arm. The bulge drops low in the arm (Popeye) | Often only a little weaker | A doctor soon. Often managed without surgery |
| Brachialis strain | Built up over weeks of pulling, curls or climbing, or a twinge with no pop | Deep at the front of the elbow, under the biceps. Shape unchanged | Usually comfortable. Bending against load with the palm down aches | Loading the muscle back in stages |
| Tennis elbow | No injury. It comes on over weeks of gripping | Outside of the elbow | Normal. Gripping and lifting a kettle hurt | Assessment and graded loading |
| Golfer’s elbow | No injury. Pulling, gripping and curling volume | Inside of the elbow | Normal. Gripping and turning the palm down hurt | Assessment and graded loading |
| Inner elbow ligament sprain (UCL) | Throwing, or a fall onto an outstretched hand | Inside of the elbow, worst at the point of release in a throw. See the throwing arm in baseball and softball injuries | Normal | A doctor if it followed a fall or the elbow feels unstable |
Why the first weeks matter
Once the tendon lets go of the radius, the biceps keeps pulling on it and nothing pulls back. Surgeons find the tendon end easier to bring back to the bone within about 2 weeks of the injury. After that it tends to scar where it has retracted, and bringing it back to its attachment gets harder.2
Leaving a complete tear unrepaired has a measured cost. In a 1985 study, three people treated without surgery lost, on average, 40% of their strength turning the palm up and about 30% of their elbow bending strength, measured at follow-up.3 The study was small. A 2010 review concluded that healthy, active people do better with early repair, with more strength turning the palm up and, to a lesser degree, bending the elbow.2
Not everyone has the tendon repaired. Some people with lighter demands on the arm choose not to, and that is a reasonable decision made with a surgeon. Hand therapy has a part either way.
Early or late, the decision about the tendon belongs to an orthopedic or hand surgeon, and the route to one is your GP, a polyclinic, or the emergency department. Hand therapy cannot reattach a tendon, and nothing on this page replaces that visit. Ask the doctor one question: is the biceps tendon still attached at the elbow?
Distal biceps rupture treatment: who does what
- A doctor (your GP, a polyclinic doctor or the emergency department) examines the arm, runs the hook test, decides on an ultrasound or an MRI, and refers you to a surgeon.
- An orthopedic or hand surgeon reattaches the tendon to the radius, and decides what is possible for a partial or a late tear.
- A hand therapist takes over after the repair: the brace or splint, the protected movement your surgeon’s protocol allows, the swelling and the scar, then strength and the return to lifting. For a partial tear, or an arm a surgeon has decided not to repair, the hand therapist runs the loading in stages.
After the repair
Many surgeons use a hinged elbow brace or a splint that limits how far the elbow straightens in the first weeks, opened up in steps. Your surgeon’s protocol sets the range and the weeks. At Phoenix a custom thermoplastic splint is molded at the visit when your surgeon wants one.
Two nerves run close to the repair. The lateral antebrachial cutaneous nerve carries feeling on the thumb side of the forearm, so numbness or tingling there is worth reporting. The posterior interosseous nerve lifts the fingers and thumb, so trouble straightening the fingers or lifting the thumb needs your surgeon the same day. Nerve irritation is a recognized complication of the repair.2 We check both at every visit.
In the Phoenix Recovery Protocol the work after a repair starts at Calm & Protect: the brace, the wound, swelling control and the exact movements your protocol allows. Move & Mobilize opens the brace in steps and brings back full straightening and turning the palm both ways. Rebuild & Strengthen loads the biceps once your surgeon allows it; strengthening usually starts from around 8 to 12 weeks. Return & Perform tests the tasks themselves: the bar, the cement bag, the screwdriver, the child lifted from the car seat. Heavy lifting is usually not before 4 to 6 months, on your surgeon’s protocol. See hand therapy after surgery.
What we measure
- The hook test, written down. If it points to a torn tendon and you have not seen a doctor, we write to your doctor that day. There is nothing to rehabilitate until a surgeon has decided about the tendon.
- Elbow range. How far the elbow straightens and bends, in degrees, against the other arm.
- Forearm turning range. Palm up and palm down, in degrees.
- Turning strength and bending strength. Palm-up turning and elbow bending, against the other arm, once your surgeon allows load. These are the two numbers that decide the return to lifting.
- Grip. In kilograms, on both hands.
- Sensation and the scar. Feeling along the thumb side of the forearm, finger and thumb lifting, and how the scar moves.
Tested, not dated. The plan moves on when the measures say so.
What you can do this week
- Write down the date, the time and what you were lifting, and take that to the doctor.
- Do the hook test once. Curling a dumbbell or lifting a bag to check tells you nothing new.
- Rest the arm in a comfortable position, and use a cold pack wrapped in a cloth for 10 to 15 minutes at a time.
- Take off a watch or a tight bracelet on that side. Bruising and swelling can spread down the forearm.
- Keep the fingers and wrist moving, so the hand does not stiffen while you wait.
- After a repair: wear the brace as instructed, including at night if your surgeon says so. Do not test your strength, and do not carry what your protocol has not allowed yet.
- Pain relief and anti-inflammatory medication are a decision for your doctor or pharmacist.
Is this normal?
Usually expected: after the injury, bruising that spreads down the forearm over the first week and turns yellow as it fades. After a repair, swelling for weeks, an elbow that does not fully straighten while the brace limits it, a tight scar across the elbow crease, and a small numb patch near the scar that shrinks week by week.
Worth getting checked: turning the palm up that is still weak a week after a pop at the elbow. After a repair, numbness along the forearm that is spreading or not shrinking, or an elbow that is not straightening further from one month to the next.
When to see a doctor first
- Call 995 for arm pain with chest pain, breathlessness or sweating, or a wound that is bleeding heavily and firm pressure does not slow it.
- Go to the emergency department now if the forearm is swelling fast and feels tight, with pain far out of proportion to the injury or a hand that is going numb. Also if the elbow looks out of place after a fall, or the hand turns cold, pale or blue.
- See a doctor the same day for a pop at the front of the elbow with bruising, weakness turning the palm up, or a change in the shape of the biceps. After a repair, contact your surgeon the same day if you feel a sudden give or pop and lose strength, if you cannot straighten the fingers or lift the thumb, if the brace breaks, or if the wound is red, leaking or more painful, or you have a fever.
- See a doctor soon for an ache at the front of the elbow with pain or weakness turning the palm up that is still there two weeks on, even with no pop, which can be a partial tear. Also for a pop at the front of the shoulder with a new bulge low in the arm, covered in biceps tendonitis and long head tears.
Where are you with this right now?
1. The tendon is there, and it is settling
The hook test finds a firm cord on both arms, turning the palm up is as strong as the other side, and the ache at the front of the elbow is easing week by week. That is more likely a strained muscle behaving as expected. Brachialis strain covers loading it back. You do not need us for this, and we would rather say so.
2. It has been weeks, and turning the palm up is still weak
It went while you lowered the end of a sofa. The elbow still bent, so you called it a strain. Three weeks on, the bruise has faded.
The screwdriver goes to the other hand. So does the door key, the jar lid and the bowl of soup carried palm up. The deadlift bar has stayed on the rack, and at work someone else lifts the boxes on your side.
Waiting for it to settle made sense for a strain. A tendon off the bone has nothing to settle, and in your own weeks the turning has not come back.
The bruising is gone. Has anyone measured how strongly that forearm turns palm up?
That question goes to a doctor first, through your GP, a polyclinic or the emergency department, even weeks later. A surgeon sets out what is still possible for a late tendon. If you cannot tell a strain from a tear, one Assessment & Treatment with a hand therapist answers it: we run the hook test, measure turning strength against the other arm, and if the tendon has gone, we write to your doctor that day.
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3. You have had the repair, or you have a date
The surgeon puts the tendon back on the radius. The weeks after decide how the elbow straightens and how strongly the forearm turns. See hand therapy after surgery. Your surgeon’s protocol takes precedence.
If it is months on and the elbow still stops short of straight, or the palm-up turn is still weak against the other arm, the Stalled Recovery Review is three weeks with the same hand therapist. The first visit measures range and turning strength. The next two measure how they respond.
All of it runs on the same four stages. The Phoenix Recovery Protocol explains what each stage works on and what you have to meet to move up. No referral needed to start.
Next step
Find out which stage you are in
Pain is the first thing to leave. Movement and strength are the last things trained back, and most people stop before that part is done. One Assessment and Treatment is a single 45-minute appointment at $230, nett, no GST. Your therapist finds what is actually limiting you, treats it in the same appointment, and you leave with your current stage and a written plan.
Prefer to phone? Each of our five clinics has its own number on the clinics page. No referral needed to book.
Related reading
Sources: 1. O’Driscoll SW, Goncalves LB, Dietz P. The hook test for distal biceps tendon avulsion. Am J Sports Med. 2007;35(11):1865-1869. 2. Sutton KM, Dodds SD, Ahmad CS, Sethi PM. Surgical treatment of distal biceps rupture. J Am Acad Orthop Surg. 2010;18(3):139-148. 3. Morrey BF, Askew LJ, An KN, Dobyns JH. Rupture of the distal tendon of the biceps brachii. A biomechanical study. J Bone Joint Surg Am. 1985;67(3):418-421.
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