Pain guide · Elbow pain

Exercises after a broken or dislocated elbow: the recovery stages and how to get your elbow straight again

Most adult elbow injuries are a break at the top of the radius (the radial head), a break in the point of the elbow (the olecranon), or a dislocation. Many heal without surgery, and the main long-term problem is usually not the bone but stiffness: straightening is the last movement to come back.

Your fracture team's plan comes first, and timings differ between hospitals. For most radial head fractures and simple dislocations, gentle movement starts within days; after a half-cast or an operation, it starts when your team says. This guide sets out the usual stages from NHS fracture leaflets, from the sling to full strength, with a 3D demo of each move, what trials found about early movement and surgery, and the warning signs.

4-stage exercise plan When to get help 36 sourcesUpdated 21 October 2026

When to get help first

Exercise is for pain that has been checked or is clearly mild and settling.

Get urgent medical help if

Go to A&E or call 999 if you've injured your arm and it is numb, tingling or has pins and needles; a bone is sticking out or a bad cut is bleeding heavily; or the arm or elbow has changed colour or shape, or is at an odd angle. Don't drive yourself.
Go to A&E: the hand is cold, white or purple, or the fingers are numb or won't move. The artery or nerves at the elbow may be injured. While you're recovering, if the feeling in your fingers gets much worse, or you lose feeling or can't move your fingers, contact your fracture clinic straight away, or go to A&E out of hours.
Call 999 or go to A&E: sudden, severe pain in a muscle of the forearm or hand, especially after an injury or when a cast or bandage feels too tight. It can be compartment syndrome.
While it heals, get help from NHS 111 the same day if the pain gets worse; your temperature is very high or you feel hot, cold or shivery; the cast or splint breaks or feels too tight or too loose; your fingers or hand feel numb, look swollen, or turn blue or white; or there is a bad smell or fluid coming from under the cast.
After an operation, oozing or pus from the wound: ask for an urgent GP appointment or get help from NHS 111. If you feel unwell or feverish and the wound looks infected, go to A&E.
Arm pain or swelling with breathlessness or chest pain: call 999 or go to A&E, and do not drive yourself. It can be a blood clot that has reached the lungs.
Throbbing pain and swelling in the arm, with red, blue or darker skin and swollen veins: ask for an urgent GP appointment or get help from NHS 111. It could be a blood clot.
Same day (NHS 111): after a fall or knock you can't fully straighten the elbow, or the injured arm is very painful, very swollen or bruised, or stiff and hard to move. In a large study, about half of people who couldn't fully straighten the elbow after an injury had a fracture.
Call 999: arm pain that comes on suddenly with pressure, heaviness, tightness or squeezing across your chest, especially with shortness of breath, sweating or feeling sick. It could be a heart attack.

See a doctor or physiotherapist if

Pain that is severe or hard to manage, or you're worried the elbow isn't improving: contact your fracture clinic. If you're struggling to get back to exercise or your usual activities, the fracture service can advise.
Pins and needles in the ring and little fingers that keep coming back or don't go away, or a weak or clumsy hand: tell your team. The ulnar nerve runs behind the elbow.
Pain that is getting worse instead of better, swelling with fingers that are hard to bend, skin that is shiny, red or very sensitive to touch, or a hand that doesn't feel like yours: contact your fracture clinic or physiotherapist promptly. These can be early signs of complex regional pain syndrome (CRPS), and early treatment helps.
You're 50 or over and broke your elbow in a fall from standing height or less: ask about a bone health check, and about a falls assessment if you fell.

Understand it

Three common adult injuries

The elbow is a hinge between the upper arm bone and the ulna, with the head of the radius turning beside it as you turn your palm up and down. A break in the top of the radius (a radial head or neck fracture) makes up about 20% of sudden elbow injuries, more often in women and in people aged 30 to 40. The American Academy of Orthopaedic Surgeons (AAOS) describes small cracks with the pieces still fitted together (type 1), slightly shifted breaks with a bigger piece (type 2), and breaks in many pieces, usually with ligament damage (type 3). In a study of 237 people, 185 had type 1 or 2 breaks, and only 2 of them had an operation.

A break in the point of the elbow (the olecranon), where the triceps attaches, is common in older people, and breaks that have shifted are often fixed with wires or a plate. In a dislocation, the joint comes out of place, usually after a fall on an outstretched hand. A simple dislocation damages ligaments without a major break; a complex one comes with fractures and often needs surgery. In US data, dislocations happened to about 5 in 100,000 people a year, and almost half happened during sport.

Sources 1, 2, 3, 4, 5, 6

How it's recognised

Pain, swelling, bruising and an elbow that won't straighten. In a study of 1,740 people with an elbow injury, about half of those who couldn't fully straighten the elbow had a fracture. Being able to straighten it fully made a fracture unlikely in adults, though it missed a few breaks of the point of the elbow. Only an X-ray shows for sure whether it's broken.

A cool, white or purple hand can mean the artery at the elbow is injured, and numb or weak fingers a nerve injury: both need A&E.

Sources 7, 5

How it's treated: your team's choice

Most radial head and neck fractures need only a sling for comfort for a few days, no cast, and sometimes no fracture clinic follow-up. NHS leaflets ask you to start moving straight away, and say moving it won't stop the fracture healing. Some shifted or shattered breaks need an operation to fix or replace the radial head.

After a simple dislocation is put back, one NHS service uses a sling for comfort, no cast, and a specialist review at 10 to 14 days to check the elbow is stable; the AAOS describes 1 to 3 weeks in a splint or sling. An olecranon fracture treated without an operation may go in a half-cast (backslab) with a sling, with a review at about 1 week. After an operation, one NHS hospital starts gentle movement on the day of surgery.

Sources 8, 9, 1, 10, 5, 11, 3

What recovery looks like

After a radial head fracture, the pain usually settles in 3 to 6 weeks and it can take months to feel normal; one NHS leaflet expects normal use by 6 to 8 weeks and healing in 6 to 12 weeks. A slight loss of straightening is common but rarely matters. In 237 people, 93% had good or excellent results at a year.

Dislocations usually heal in 6 to 12 weeks, and olecranon fractures in 6 to 8. In 110 adults seen about 7 years after a simple dislocation, function was good, but 56% still noticed some stiffness and 62% some pain, and 8% felt the elbow was a little unstable.

Sources 8, 9, 2, 10, 11, 12

Why stiffness matters

Straightening is usually the slowest movement to come back, and it may stay a little limited. Even the simplest fractures lose some movement, the AAOS says. Stiffness affects up to about half of people after an elbow injury, and losing half the elbow's range costs about 80% of the arm's usefulness.

Most daily tasks need the elbow to bend from about 30° to 130° and the forearm to turn about 50° each way. Some modern tasks need more: about 142° of bend to hold a phone to your ear, and more turning to type or open a door.

Sources 13, 1, 14, 15, 16

What helps, and how strong the evidence is

A simple dislocation does better moved earlyStrong evidence

In the FuncSiE trial, 100 adults with a simple dislocation either started moving the elbow within days or spent 3 weeks in plaster. At a year, arm function was the same. At 6 weeks the early group had less disability and more movement (an arc of 121° against 102°), and went back to work sooner (10 days against 18). Nobody's elbow came out again, and the 12 complications weren't linked to the treatment.

Average costs at a year were about half with early movement, though that difference could be chance. A review of 29 studies (5,765 people) found good or excellent results in 83% with early movement against 78% after 2 weeks or more of immobilisation.

Sources 17, 18, 19

Most radial head fractures heal well without surgeryStrong evidence

In a study of 237 people with radial head and neck fractures, 93% had good or excellent results at a year, and almost all of the simpler (type 1 and 2) breaks were treated without an operation. Older age, more complex breaks, more fragments and surgery went with worse results. NHS leaflets treat these breaks with a sling for comfort and early movement, often without follow-up.

Sources 2, 8, 9

When to start moving after a radial head fracture: a short sling may be bestMixed evidence

In a trial of 180 people with simple radial head fractures, 2 days in a sling and then movement gave better movement, strength and function than moving straight away or 7 days in a cast; moving straight away hurt more for the first 3 days. Breaks shifted more than 4 mm, or tilted more than 30°, did worse. A Cochrane review found too little good evidence to say exactly when movement should start.

Sources 20, 21

Draining the joint: not enough evidenceMixed evidence

Draining blood from the joint with a needle after a radial head fracture was tested in 2 small trials (108 people) of very low quality. It may ease pain straight away, but function at a year was about the same.

Source 22

Olecranon fractures from 75: surgery isn't clearly betterEmerging evidence

In a trial of 19 people aged 75 or over with a shifted break, 9 of the 11 who had an operation had complications, so the trial was stopped early; arm function at a year was about the same in both groups. In the SOFIE trial (60 people aged 75 or over, average age about 82, in 24 hospitals in Australia and New Zealand), a sling and early movement gave arm function at a year that was not clearly different from surgery: the scores leaned a little towards surgery, but the difference could be chance, and surgery gave better straightening.

A review found similar results with or without surgery in older people, and more repeat operations after surgery, and in 43 older people treated without surgery, function years later was good. Breaks that have shifted are often fixed with wires or a plate, and your surgeon will advise.

Sources 23, 24, 25, 4, 3

Stiffness: gentle stretching helps, forcing doesn'tEmerging evidence

A 2025 review of 9 studies (312 people) found that 3 small trials of gentle hold-relax stretching for early stiffness after an elbow injury reported worthwhile gains with no harms; splints for long-lasting stiffness also helped but caused more problems. A 2024 review found large benefits when therapy started straight after the elbow came out of a cast or sling, but the certainty was low to very low.

NHS leaflets advise gentle, frequent movement rather than forcing: forcing the elbow is unnecessary, can be painful and can delay recovery.

Sources 14, 26, 8, 27, 13

The usual exercises: consistent NHS advice, not trial-testedEmerging evidence

NHS fracture leaflets agree on the order: fingers, wrist and shoulder from day one; bending, straightening and turning the forearm from the first days if your team allows; a lying overhead straighten that lets gravity help; nothing heavier than a cup of tea for 6 weeks; then held stretches and strengthening once healed. This is consistent advice, but trials haven't compared these exact exercises.

Sources 10, 8, 9, 28, 3

Bone health and fallsStrong evidence

If you're 50 or over and broke your elbow in a fall from standing height, it may be a fragility fracture, a sign of weaker bones. The National Institute for Health and Care Excellence (NICE) asks for a fracture risk assessment for everyone 50 or over, and women past the menopause, after a fragility fracture, and a falls assessment for people who fell in the past year and needed treatment.

Sources 29, 30

How much pain is OK while you exercise?

Bearable, settling within 30 minutes to 2 hours, never forcedEmerging evidence

NHS fracture leaflets say some discomfort while you exercise is normal. It should be bearable and settle within about 30 minutes (one leaflet) or at most 2 hours (two others), and the elbow shouldn't become hot, inflamed or more swollen afterwards. In the first days, move into mild discomfort but not pain, and ease off for sharp or shooting pain.

Never force it: help from the other hand should be gentle. If pain doesn't settle, do shorter sessions more often, don't push into the pain, and review your painkillers. Stop any position that brings on pins and needles in the ring and little fingers.

Sources 8, 9, 3, 13, 28, 27

The exercise plan: 4 stages

Start at the first stage. Each move opens a full guide with a 3D demo.

Stage 1

The first days: fingers, wrist, shoulder and neck (as your team allows)

As your team allows, from the day of the injury. Use the sling for comfort, and take it off to wash, dress and exercise unless you have a half-cast (backslab). Rest the elbow for 1 to 3 days, but keep the fingers, wrist, shoulder and neck moving so they don't stiffen. Ice for up to 10 to 15 minutes at a time, wrapped in a towel. Lift nothing heavier than a cup of tea.

Ball squeeze demonstrated on the 3D figure

3D demoBall squeezeBeginner · Other / check instructions

Squeeze as hard as is comfortable, hold 5 s, 10 times, 4 to 5 times a day · A soft ball or rolled socks. An NHS leaflet's dose

Harder: Band finger extension

Tendon glides (hand tendon gliding exercises) demonstrated on the 3D figure

3D demoTendon glides (hand tendon gliding exercises)Beginner · No equipment

4 to 6 of each position, holding each 5 s, up to 4 times a day · An NHS hand-therapy leaflet's dose

Harder: Ball squeeze

Wrist & forearm flow demonstrated on the 3D figure

3D demoWrist & forearm flowBeginner · No equipment

Wrist bending and straightening, 10 times, 4 to 5 times a day · Leave out the palm turns while you're in a half-cast. An NHS leaflet's dose

Harder: Wrist flexor stretch

Breath reach demonstrated on the 3D figure

3D demoBreath reachBeginner · No equipment

5 slow breaths, lifting the arms as high as is comfortable, a few times a day · Support the injured arm with the other hand; the elbow can stay bent or in the sling

3D demoNeck CARsBeginner · No equipment

Gentle nods, turns and tilts, 5 of each, a few times a day · Editorial dose

Move on when: Your team says the elbow can move: within the first days for most radial head fractures and simple dislocations, when the half-cast comes off for an olecranon fracture treated without surgery, or straight after an operation if your surgeon allows.

Follow along: a timer, a cue and the next move, one step at a time.

Stage 2

Get the elbow moving (as your team allows)

As your team allows. Little and often: bend, straighten and turn the forearm every 2 to 3 hours, into mild discomfort but not pain, never forced. Straightening comes back last, so give it the most attention; the lying overhead straighten in the notes below lets gravity help. For 6 weeks, lift nothing heavier than a cup of tea, and don't push up through the hand on chair arms or doors.

Elbow bend and straighten (elbow range of motion) demonstrated on the 3D figure

3D demoElbow bend and straighten (elbow range of motion)Beginner · No equipment

10 times, 3 to 4 times a day, holding each end for 5 to 10 s · The other hand can help gently. An NHS leaflet's dose

Harder: Dumbbell biceps curl

3D demoWrist & forearm flowBeginner · No equipment

Palm up and palm down with the elbow tucked at your side and bent to a right angle, 10 times, 3 to 4 times a day · A mild stretch, not pain. NHS leaflets' dose

Harder: Wrist flexor stretch

Table slide (seated forward reach) demonstrated on the 3D figure

3D demoTable slide (seated forward reach)Beginner · A bench or box

10 slow slides, 3 times a day, letting the forearm slide forward so the elbow straightens · Used after an olecranon operation in an NHS leaflet; the dose is the move page's

Easier: Pendulum exercise (Codman's pendulum) · Harder: Overhead lat stretch at a bench

3D demoBall squeezeBeginner · Other / check instructions

Hold 5 s, 10 times, 4 to 5 times a day

Harder: Band finger extension

Move on when: Your team says the bone or ligaments have healed enough for stretching and light loading, often at about 6 weeks, and the elbow moves a little further each week.

Follow along: a timer, a cue and the next move, one step at a time.

Stage 3

Stretch towards full range (often from about 6 weeks, as your team allows)

As your team allows, once the fracture has healed. Hold the ends of the range for longer, with gentle pressure from the other hand and gravity helping you straighten, never forcing. Work most on whatever is missing: most daily tasks need about 30° to 130° of bend and some turning of the forearm each way. Gentle swimming can start 4 to 6 weeks after an olecranon operation if your surgeon agrees.

3D demoElbow bend and straighten (elbow range of motion)Beginner · No equipment

Hold 30 s at each end with gentle pressure from the other hand, 3 times a day · An NHS leaflet's hold

Harder: Dumbbell biceps curl

3D demoWrist & forearm flowBeginner · No equipment

Palm up and palm down with a 5 s hold at each end, 10 times, 3 times a day · An NHS leaflet's dose

Harder: Wrist flexor stretch

3D demoTable slide (seated forward reach)Beginner · A bench or box

10 slides with a 10 to 20 s hold at the far end, 1 to 3 times a day · The move page's dose

Easier: Pendulum exercise (Codman's pendulum) · Harder: Overhead lat stretch at a bench

Overhead Triceps Stretch demonstrated on the 3D figure

3D demoOverhead Triceps StretchBeginner · No equipment

3 gentle holds of 20 to 30 s · For bending. Skip it if it brings on tingling in the ring and little fingers. Editorial dose

Harder: Overhead lat stretch at a bench

Wrist circles demonstrated on the 3D figure

3D demoWrist circlesBeginner · No equipment

10 slow circles each way, once or twice a day · Editorial dose

Harder: Wrist flexor stretch

Move on when: The elbow is close to its new full range, or still improving week by week, and your team says it can take load.

Follow along: a timer, a cue and the next move, one step at a time.

Stage 4

Strengthen (often from about 6 to 12 weeks, as your team allows)

As your team allows. Rebuild strength with light weights 2 to 3 times a week, adding a little at a time, and keep the stretches going. After an olecranon operation, start triceps work only when your surgeon allows. One NHS leaflet allows contact sport 6 weeks after a radial head fracture; another says no racquet or contact sport until the elbow is pain-free, supple and strong. These doses are editorial.

Dumbbell biceps curl demonstrated on the 3D figure

3D demoDumbbell biceps curlBeginner · A dumbbell

0.5 to 2 kg, 2 to 3 sets of 10 to 15, slowly

Easier: Seated dumbbell curl · Harder: Incline inner biceps curl

Dumbbell triceps kickback demonstrated on the 3D figure

3D demoDumbbell triceps kickbackBeginner · A dumbbell

Light, 2 sets of 10 to 15 · After an olecranon operation, only when your surgeon allows

Harder: Dumbbell skull crusher (lying triceps extension)

Dumbbell forearm rotation demonstrated on the 3D figure

3D demoDumbbell forearm rotationBeginner · A dumbbell + A bench or box

A light hammer or a dumbbell held at one end, 2 to 3 sets of 10 to 15

Easier: Wrist-extensor eccentrics · Harder: Forearm plank

Reverse wrist curl demonstrated on the 3D figure

3D demoReverse wrist curlBeginner · A dumbbell + A bench or box

Light, 2 to 3 sets of 10 to 15, 2 to 3 times a week

Easier: Wrist-extensor eccentrics · Harder: Plate pinch

Wall push-up demonstrated on the 3D figure

3D demoWall push-upBeginner · A wall

2 sets of 10 · Once the elbow straightens comfortably and your team allows weight through the arm

Harder: Push-up

Farmer's carry demonstrated on the 3D figure

3D demoFarmer's carryBeginner · A dumbbell + A kettlebell

Light, 3 carries of 20 to 30 m

Harder: Suitcase carry

Move on when: Everyday tasks are pain-free and your strength is close to the other side. Then build back to sport gradually.

Follow along: a timer, a cue and the next move, one step at a time.

What to change for now

Typical timings, which your team may change

These come from NHS leaflets, and they differ. Your own team's timings come first.

Sling: for comfort, usually a few days and up to about 2 weeks; take it off to wash, dress and exercise. A half-cast for an olecranon fracture stays on until the fracture clinic reviews it.
Moving the elbow: from the first days for most radial head fractures and simple dislocations; when your team says after a half-cast or an operation.
Lifting: nothing heavier than a cup of tea for about 6 weeks, and no pushing up through the hand.
Swimming: gently, 4 to 6 weeks after an olecranon operation, if your surgeon agrees. Swimming is good exercise as the elbow recovers.
Contact sport: from 6 weeks after a radial head fracture in one NHS leaflet; another says wait until the elbow is pain-free, supple and strong.
Driving: not in a sling. Drive once you can turn the wheel and do an emergency stop without pain or hesitation, and check with your insurer.

Sources 8, 9, 28, 10, 11, 3, 13

The lying overhead straighten (written steps)

Two NHS leaflets use this to help the elbow straighten, with gravity doing some of the work. Start when your team says the elbow can move.

1. Lie on your back with a pillow under your head.
2. Raise the injured arm so the elbow points at the ceiling, and support the upper arm with your other hand.
3. Slowly straighten the elbow, as if pointing at the ceiling.
4. Slowly lower the hand back towards the pillow, bending the elbow as far as is comfortable.
5. Repeat 10 times, 4 to 5 times a day. If your shoulder won't allow this position, lie with the arm resting by your side and bend and straighten the elbow there.

Sources 10, 8

Move the elbow, not the shoulder

It's easy to let the shoulder or body do the work. One NHS leaflet suggests watching the crease at the front of the elbow open and close as you exercise, and stopping each repetition where it stops moving.

Source 3

Positions to swap, and why

Habit or position	Why it matters	Instead
Keeping the arm in the sling all day for weeks	The sling is for comfort; the elbow, wrist and shoulder stiffen in it.	Take it off to wash, dress and exercise, and wean off it as the pain allows.Try: Elbow bend and straighten (elbow range of motion)
Forcing the elbow straight, or letting someone push it	NHS leaflets say forcing is unnecessary, can be painful and can delay recovery.	Gentle, frequent sessions, and let gravity help you straighten it lying down.Try: Table slide (seated forward reach)
Carrying shopping or lifting more than a cup of tea in the first 6 weeks	NHS fracture leaflets set that limit while the elbow heals.	The other hand, and small, light loads.
Pushing up through the hand on chair arms or doors, especially after an olecranon operation	It loads the healing bone and the triceps attachment.	Stand up using your legs, and push doors with your body or the other hand.Try: Sit to stand from a chair
Long holds with the elbow fully bent, or leaning on it, if the ring and little fingers tingle	It squeezes the ulnar nerve behind the elbow.	Shorter holds, and don't lean on the elbow.
Driving in a sling	NHS leaflets say not to.	Wait until you're out of the sling and can turn the wheel and stop suddenly without pain.
Push-ups before the elbow straightens comfortably	They load the elbow at full straightening, the last movement to come back.	Wall push-ups once your team allows weight through the arm.Try: Wall push-up
Racquet or contact sport too soon	NHS leaflets say wait until the elbow is pain-free, supple and strong, or about 6 weeks after a radial head fracture.	Walking meanwhile, and gentle swimming once your team allows.Try: Treadmill walking

Routines to follow

Wrist and forearm routine

Wrist mobility and forearm strength for desk work, climbing, push-ups and handstands.

10 minBeginner7 movesA wall, A dumbbell

Grip strength workout: squeezes, curls, carries and hangs

A 20-minute grip session: warm up the wrists and fingers, train the hand and forearm muscles, then carry and hang to load your grip the way everyday life does.

20 minBeginner10 movesOther / check instructions, A band

Joint care workout: move and strengthen every joint

A 25-minute session for healthy joints: slow circles to take every joint through its range, then a strength circuit for hips, knees, ankles, shoulders and grip.

25 minBeginner13 movesA wall, A bench or box

More moves for this area

Questions people ask

How long does a broken elbow take to heal?

Most radial head fractures and dislocations heal in about 6 to 12 weeks, and an olecranon fracture in about 6 to 8. It can take months to feel normal, and straightening is usually the last movement to come back.

When should I start moving my elbow?

For most radial head fractures and simple dislocations, within the first few days, as your fracture team advises; NHS leaflets say moving it won't stop it healing. After a half-cast or an operation, start when your team says.

What exercises help after a broken elbow?

Start with finger, wrist and shoulder movements, then gentle bending, straightening and forearm turning every few hours, and a lying overhead straighten that uses gravity. Once it has healed, longer held stretches and light strengthening.

Why can't I straighten my elbow after a fracture?

Losing some straightening is very common after an elbow injury, and it's the slowest movement to return. Gentle, frequent stretching helps, and most people end up with enough movement for daily life. If it stops improving, ask about physiotherapy.

Do I need surgery for a broken elbow?

Most radial head fractures heal without it. Olecranon fractures that have shifted are often fixed, but from about 75, trials found similar function at a year without surgery. Your fracture team will advise on your break.

How long will I need a sling?

Usually only for comfort, for a few days and up to about 2 weeks; take it off to wash, dress and exercise. A half-cast for an olecranon fracture stays on until the fracture clinic reviews it.

How long does a dislocated elbow take to recover?

It usually heals in 6 to 12 weeks. In a trial of 100 adults, those who started moving it within days were back at work in about 10 days, against 18 after 3 weeks in plaster. Some stiffness for months is common.

Is it normal for my elbow to hurt when I exercise?

Some discomfort is normal; it should be bearable and settle within 30 minutes to 2 hours. If it doesn't, or the elbow gets hot or more swollen, do shorter, more frequent sessions and don't push into the pain.

When can I drive after a broken elbow?

Not while you're wearing the sling. You can drive once you can turn the wheel and do an emergency stop without pain or hesitation, and your insurer agrees.

When can I go back to the gym or sport?

Keep lifting to a cup of tea for the first 6 weeks. One NHS leaflet allows contact sport from 6 weeks after a radial head fracture, and another says to wait until the elbow is pain-free, supple and strong. Build up weights gradually from there.

Related exercise guides

Elbow joint guide

Other pain guides

Sources

Exercise education, not a diagnosis or treatment plan. It is written from the guidelines and studies listed above; review by a clinician is pending. If your pain follows an injury, is severe, is getting worse, or comes with any warning sign listed on this page, get it assessed. Health disclaimer.