Arm tendonitis covers three zones: the biceps tendon at the front of the shoulder, the tendons at the outer or inner elbow, and the forearm tendons running to the wrist. All three respond to graded loading over about twelve weeks, and all three get worse with complete rest.
The word tendonitis promises inflammation. In a tendon that has hurt for more than a few weeks, biopsies find very little of it. What they find is disorganised collagen and a tissue that has failed to keep up with what was asked of it, and that changes the treatment completely.
Three zones, and how to tell them apart
Front of the shoulder
Biceps tendonitis. A deep ache at the front of the shoulder, worse lifting in front of you, carrying shopping, or reaching up to a high shelf.
Outer or inner elbow
Tennis elbow on the outside, golfer’s elbow on the inside. Provoked by gripping, wringing a cloth, or lifting a kettle with the palm down.
Forearm and wrist
The extensor and flexor tendons where they run towards the wrist. Typing, mouse work, trade tools and repeated twisting are the usual histories.
The arm is not one structure. Pain at the front of the shoulder that worsens when you lift something in front of you with the palm up points to the long head of the biceps tendon, which runs in a groove at the top of the arm bone and is loaded every time you lift forwards.
Pain on the outside of the elbow, provoked by gripping, is tennis elbow, which is the common extensor tendon where the muscles that lift the wrist anchor into bone. Most people who get it have never held a racket. On the inside of the elbow, the mirror image is golfer’s elbow, provoked by pulling and gripping with the palm down.
Further down, the forearm tendons themselves become sore with sustained keyboard and mouse work or with repetitive trade tasks, and where they cross into the hand they separate into the named conditions covered under wrist tendonitis. This is the group most often described as repetitive strain, and it is the group where changing the workstation matters more than any treatment.
| Movement that hurts | Likely tendon | First thing to change |
|---|---|---|
| Lifting a weight in front of you, palm up | Biceps, at the shoulder | Carry loads at your side, not in front |
| Gripping, or lifting a mug palm down | Common extensor, tennis elbow | Lift with the palm up, widen every handle |
| Wrist bending down against resistance | Common flexor, golfer’s elbow | Cut repetitive pulling and gripping loads |
| Mouse and keyboard after 20 minutes | Forearm extensors | Desk height, wrist position, breaks every half hour |
| Thumb side of the wrist, lifting a baby | De Quervain’s tenosynovitis | Change the lifting grip, consider a thumb splint |
Why complete rest backfires
What most people do, and what the evidence supports
The usual response
- Rest the arm completely until it stops hurting.
- Anti-inflammatories for weeks at a time.
- A support strap worn all day, indefinitely.
- An early steroid injection to clear it up.
- Return to the same task at the same intensity.
- Stretch hard into the painful spot.
What actually works
- Reduce the aggravating task, keep using the arm.
- Short course of pain relief to allow movement.
- A strap for specific heavy tasks only.
- Loading first; injection only if it stalls.
- Return graded over weeks, with the task modified.
- Load the tendon slowly and heavily instead.
The instinct is understandable. It hurts when you use it, so you stop using it, and for a fortnight things improve. What happens underneath is that the tendon, which maintains its structure in response to load, quietly loses capacity. Then normal life resumes, the demand returns to where it was, and the tendon is less able to meet it than before.
This is the mechanism behind the relapse pattern that so many people describe: better after three weeks off, sore again within a fortnight of going back, and worse each time round. Every cycle leaves the tendon weaker.
Relative rest is the alternative. Cut the specific aggravating action, keep everything else, and start loading the tendon deliberately within days rather than weeks. It feels counterintuitive and it is the single most evidence supported change you can make.
What a loading programme looks like for the arm
The first phase is isometric: hold a light weight or push against an immovable object for around 40 seconds, five times, with the joint still. It loads the tendon with almost no movement, is well tolerated even when things are irritable, and often reduces pain for a few hours afterwards.
The second phase is the one that changes the tissue. Slow heavy resistance means real load moved deliberately, roughly three seconds in each direction, two or three sessions a week. For tennis elbow that is wrist extension with a dumbbell or a weighted bar. For biceps tendonitis it is controlled curls and forward raises. For golfer’s elbow it is wrist flexion and gripping work.
The third phase adds speed, range and the specific demands of your job or sport. A plasterer needs overhead endurance, a climber needs grip at end range, a violinist needs sustained fine control. Returning to the task in one step is where people relapse.
Twelve weeks is the realistic unit. Symptoms usually improve within three or four, which is precisely when most people stop, and stopping at week four is the commonest reason the same elbow is sore again in the spring.
The injection question
Corticosteroid injections into a painful arm tendon work impressively in the short term. Within a fortnight most people report substantial relief, and that is not in dispute.
The problem shows up later. In a randomised trial of lateral elbow tendinopathy, participants who received a corticosteroid injection had markedly better outcomes at four weeks, and markedly worse outcomes at one year, with lower rates of complete recovery and far more recurrences than those who did not receive one. The early benefit was real and it was borrowed.
That does not make injections useless. Used once, to open a window in which someone who cannot begin rehabilitation because of pain can actually start it, an injection is a defensible tool. Used repeatedly, as the treatment itself, it is how tendons end up worse three years later.
Work, tools and the things that keep reloading it
For the forearm and elbow group, the treatment that matters most is not what you do for twenty minutes a day, it is what you do for the other eight hours. A mouse held with a bent wrist, a keyboard too high, a tool with a thin handle, a task that requires the same rotation four hundred times a shift.
- Widen every handle. A fatter grip on tools, pens and utensils reduces the force the extensor tendons have to generate for the same task.
- Lift with the palm up. Carrying a kettle or a shopping bag palm down loads the tennis elbow tendon directly. Turning the hand over removes most of it.
- Fix the wrist angle. The forearm tendons are least loaded when the wrist is close to neutral, which usually means lowering a desk or raising a chair.
- Break the repetition. A two minute change of task every half hour does more than a long break at lunchtime, because it interrupts the accumulation.
- Use a strap tactically. A forearm band worn for a heavy afternoon can help. Worn all day for months it becomes a way of avoiding the loading that would fix the problem.
Things that slow tendon healing
Tendon adaptation is metabolic as well as mechanical, and several everyday factors blunt it. Poorly controlled blood sugar is strongly associated with tendon problems across the body. Smoking reduces tendon blood supply. Raised cholesterol shows a consistent association. Age slows the whole process, which is why a 55 year old elbow takes longer than a 25 year old one for the same insult.
Sleep also deserves a specific mention, because tendon pain disturbs it and poor sleep raises pain sensitivity, which is a loop worth interrupting deliberately rather than tolerating.
The general inflammatory background is part of the picture too, without being the whole of it, and it is measurable: a high-sensitivity CRP reads the range an ordinary blood test rounds away. If you are adding something alongside the loading programme, judge a bioavailable anti-inflammatory formula on how much of the active compound is absorbed rather than on the milligrams claimed, and treat a supplement aimed at tendon pain as support for the exercises. Nothing you swallow rebuilds tendon capacity. Only load does that.
Who to see, and how quickly
For a straightforward upper limb tendon problem, physiotherapy is the service you want, and in much of England you can self refer without seeing a GP first. Check your local NHS musculoskeletal service, since the route differs between areas. Going private buys speed rather than a different assessment: any registered provider will do the same physical examination and set the same kind of programme.
That assessment is short. The physiotherapist watches you move, tests strength against resistance in each direction, presses the tendon, and asks what changed in the weeks before it started. Imaging is rarely needed at this stage, because ultrasound frequently shows tendon changes in arms that have never hurt, and finding one does not tell you it is the cause of your pain.
Bring the history with you. The date it started, the activities that changed in the month before, whether there was a specific injury or a gradual build up, and which movement reproduces it. Most arm tendon problems are overuse problems in the literal sense: the demand rose faster than the tissue adapted, and the causes are almost always visible in that four week window before symptoms began.
A GP appointment is also worth having if the arm is affecting your work, since occupational adjustments are far easier to arrange with a letter than without one.
When to get it checked
- Sudden severe pain with a visible bulge or change in the shape of the muscle, which can mean a ruptured tendon.
- Real weakness rather than pain limited movement, particularly if it is progressing.
- Pins and needles, numbness, or pain spreading in a band down the arm, which points to a nerve.
- A red, hot, swollen joint, or arm pain with fever.
- No improvement after twelve weeks of a properly followed loading programme.
Frequently asked questions
How do I get rid of tendonitis in my arm?
Reduce the task that provokes it without stopping using the arm, then load the tendon deliberately. Start with isometric holds, progress to slow heavy resistance work two or three times a week, and give it twelve weeks. Pain relief and a strap make that possible but do not do the work. Complete rest is the commonest mistake: an unloaded tendon loses capacity and relapses when normal life resumes.
What does tendonitis in your arm feel like?
A localised ache you can point to with one finger, tender when you press it, and reliably reproduced by one specific movement. It is stiff and sore first thing, eases as you warm up, and is worst a few hours after the aggravating activity rather than during it. Pain that spreads in a band with pins and needles is a nerve, not a tendon.
Why am I prone to tendonitis?
Usually because of a change in load rather than a weakness in you. A new job, a new tool, a house move, a training programme started too quickly. Beyond that, age reduces how fast tendons adapt, and diabetes, raised cholesterol, smoking and some antibiotics all affect tendon tissue. Recurrence is most often explained by the last episode never being loaded back to full capacity.
How to heal tendonitis faster?
There is no shortcut past the tissue timeline, but you can avoid the things that lengthen it. Do not rest completely, do not chase a steroid injection early, do not return to the full task in one step, and do not stop the exercises when the pain goes. Sleep, protein intake and controlling blood sugar all support tendon adaptation, which is a metabolic process and not purely mechanical.
Is arm tendonitis the same as tennis elbow?
Tennis elbow is one type of it. The term arm tendonitis covers biceps tendonitis at the shoulder, tennis elbow on the outside of the elbow, golfer’s elbow on the inside, and the forearm tendons running towards the wrist. They share a mechanism and a treatment principle but not a location, and the movement that provokes the pain tells you which one you have.
Should I have a steroid injection for arm tendonitis?
Rarely as a first step. In a randomised trial of tennis elbow, patients given a corticosteroid injection were doing worse at one year than those who were not, with less complete recovery and considerably more recurrences, despite feeling much better in the first few weeks. An injection can be a reasonable way to make rehabilitation possible when pain blocks everything, but it works against you as a standalone treatment.
When should I see a GP about arm tendonitis?
If it has not improved after two to three weeks of reducing the aggravating activity, if it is stopping you working, or if there is real weakness rather than pain limited movement. In much of the UK you can self refer to NHS physiotherapy without seeing a GP first, which is usually the faster route for a straightforward tendon problem. Sudden severe pain with a visible change in the shape of the muscle needs same day assessment.
What to take away
Find the single movement that reproduces your pain exactly, and the single finger point where it lives. Those two things identify the tendon, and they take a minute. If there is no single point, and the ache is broad, burning and worst after a spell of sitting still, you are more likely dealing with fascia than with tendon.
Then change one thing at work today, and start isometric holds tonight. Twelve weeks from now the difference will be between a tendon that has been rested and a tendon that has been rebuilt.
Sources
Khan K.M., Cook J.L., Kannus P. et al. (2002). Time to abandon the “tendinitis” myth. British Medical Journal, 324(7338), 626-627. DOI: 10.1136/bmj.324.7338.626
Cook J.L., Purdam C.R. (2009). Is tendon pathology a continuum? A pathology model to explain the clinical presentation of load-induced tendinopathy. British Journal of Sports Medicine, 43(6), 409-416. DOI: 10.1136/bjsm.2008.051193
Coombes B.K., Bisset L., Brooks P. et al. (2013). Effect of corticosteroid injection, physiotherapy, or both on clinical outcomes in patients with unilateral lateral epicondylalgia: a randomized controlled trial. JAMA, 309(5), 461-469. DOI: 10.1001/jama.2013.129
Beyer R., Kongsgaard M., Hougs Kjaer B. et al. (2015). Heavy slow resistance versus eccentric training as treatment for Achilles tendinopathy. American Journal of Sports Medicine, 43(7), 1704-1711. DOI: 10.1177/0363546515584760
Sivrika A.P., Papadamou E., Kypraios G. et al. (2023). Comparability of the effectiveness of different types of exercise in the treatment of Achilles tendinopathy: a systematic review. Healthcare, 11(16), 2268. DOI: 10.3390/healthcare11162268
