Rotator cuff tendinopathy is a painful, overloaded shoulder tendon, and it's the most common reason for pain on the outside of the upper arm when you lift, reach or lie on that side. For years it was blamed on poor posture or a bone "pinching" the tendon. The research has moved on: posture shows little link with shoulder pain, removing the "pinching" bone worked no better than a placebo operation in a UK trial, and exercise is the first-line treatment. Most people improve with a few months of consistent exercise.
Key takeaways
- Typical pain: an ache on the outside of the upper arm when lifting, reaching overhead or behind your back, and lying on that side at night.
- Posture probably isn't the cause. A 2016 review found no clear difference in upper-back posture between people with and without shoulder pain.
- Decompression surgery (shaving bone to "make space") was no better than a placebo operation in the UK CSAW trial.
- Exercise is the first-line treatment, with strong evidence. Hands-on therapy can help alongside it.
- Scans can mislead: rotator cuff changes become very common with age, even in shoulders that don't hurt.
What is rotator cuff tendinopathy?
The rotator cuff is a group of four muscles whose tendons wrap around the ball of the shoulder joint. They keep the ball centred while your bigger muscles move the arm. When a tendon is asked to do more than it's ready for, for example a new gym programme, a lot of overhead work, painting a ceiling or returning to swimming, it can become painful and less able to cope with load.
You may also hear it called shoulder impingement, subacromial pain or rotator cuff tendonitis. These labels overlap. The modern view is that the tendon is overloaded and sensitive, rather than simply being pinched.
Common signs:
- pain on the outside of the upper arm, often not in the joint itself
- a painful arc when lifting your arm out to the side
- pain reaching behind your back, putting on a coat or doing your hair
- night pain, especially lying on that side
- strength usually preserved, though it may feel weak because of pain
Myth 1: "Your posture is causing your shoulder pain"
It's one of the most repeated explanations, especially for desk workers. But a 2016 systematic review of 10 studies found moderate evidence of no significant difference in upper-back rounding between people with and without shoulder pain.
Sitting up straighter does let you lift your arm a little higher in the moment, but that came from single-session studies, and whether it matters long term is unclear.
What this means: if your shoulder hurts, fixing your posture is unlikely to be the answer on its own. Changing position often is fine and can feel better, but the main treatment is strengthening the tendon. See our post on desk pain and posture.
Myth 2: "A bone is pinching the tendon, so surgery will make space"
Subacromial decompression, shaving bone from the top of the shoulder to "make space", used to be one of the most common shoulder operations. The CSAW trial, run across 32 UK hospitals, tested it properly. It randomised 313 people with at least 3 months of pain who had already tried exercise and an injection to:
- decompression surgery
- a placebo operation (a keyhole look, with no bone removed)
- no treatment
At 6 months, the two surgical groups had almost identical results on a shoulder score. Both were slightly better than no treatment, but the difference wasn't large enough to be clinically important. The authors suggested the small benefit may have come from a placebo effect or post-operative physio, and said the findings question the value of this operation.
What actually helps: exercise first
A 2020 review of 16 systematic reviews made a strong recommendation for exercise therapy as the first-line treatment, improving pain, movement and function. Hands-on (manual) therapy was strongly recommended as an add-on in the early phase. There was moderate evidence that laser, shockwave, electromagnetic therapy and ultrasound don't help.
What the evidence doesn't tell us yet: the best type of exercise, the ideal dose and exactly how long it takes. That's why a good plan is adjusted to how your shoulder responds.
A progressive exercise plan
Do these 3 times a week. Discomfort up to 3–4/10 during exercise that settles within 24 hours is OK. If the shoulder is sorer the next morning, ease back.
| Stage | Exercises | Dose | Move on when… |
|---|---|---|---|
| 1. Settle | Static holds: push your hand out against a wall (rotation) or a doorframe (sideways) | 5 × 30–45 seconds, daily | Night pain and everyday pain are easing |
| 2. Strengthen | Band or cable rotation in and out, side raises to shoulder height, rows | 3 × 10–15 | Little next-day pain |
| 3. Load | Heavier rotation, raises above shoulder height, presses with a dumbbell | 3 × 6–10, adding weight | Comfortable through full range |
| 4. Return | Overhead lifting, throwing, swimming or racket sports, built up gradually | Over several weeks | Normal training without flare-ups |
Day to day:
- Keep using your arm for normal tasks. Complete rest tends to make the tendon less tolerant.
- Reduce long periods of overhead work or reaching while it's sore.
- At night, try lying on the other side with a pillow hugged in front of you to support the sore arm.
Should I get a scan?
Usually not at first. A 2014 review of 30 studies (6,112 shoulders) found that rotator cuff changes become more common with age, rising from about 10% in people aged 20 and under to 62% in people aged 80 and over, and similar patterns appeared in people without symptoms. The authors concluded that rotator cuff degeneration is a common part of normal ageing.
So a scan report saying "tendinosis" or even a "partial tear" doesn't necessarily explain your pain. Imaging is more useful if you've had a significant injury and suddenly can't lift your arm, or if you're not improving with good rehab.
How long does it take?
Recovery varies a lot. Tendons adapt slowly, so plan to keep up the programme for at least 12 weeks, and longer if the pain has been there for many months. Night pain is often the first thing to improve.
When to see a physio, GP, 111 or 999
Call 999 if shoulder or arm pain comes with chest pain, breathlessness, sweating or feeling sick, as it can be a sign of a heart problem.
See a GP urgently or call 111 if:
- you suddenly can't lift your arm after a fall or injury
- the shoulder looks deformed after an injury
- it's hot, red and swollen and you have a fever
- you have unexplained weight loss, or constant pain that doesn't change with movement
See a physio if the pain hasn't improved in 2–3 weeks, is waking you at night, or is stopping you working, training or sleeping.
How we help at Athos Physio
Our clinic is inside F45 Manchester NQ, at 77 Piccadilly. We'll check whether the pain is coming from the rotator cuff, the joint or your neck, explain what's going on, and build a custom rehab and strengthening plan around your work, gym or sport. Hands-on treatment can help settle pain early on. You don't need a GP referral, and we work with Bupa, WPA, Vitality and Aviva. Book an appointment, or read about shoulder pain physio in Manchester.
FAQs
What is the fastest way to heal rotator cuff tendinopathy?
There's no shortcut, but the most reliable approach is a progressive strengthening programme started early, alongside reducing the activities that flare it. Passive treatments like ultrasound or laser haven't been shown to help. Expect to keep it up for at least 12 weeks.
Should I rest a sore rotator cuff?
Not completely. Complete rest makes the tendon less able to cope with load. Reduce what clearly aggravates it, such as heavy overhead lifting, but keep using the arm and start gentle strengthening.
Do steroid injections help?
An injection can reduce pain in the short term and make it easier to exercise. On its own it doesn't strengthen the tendon, so it works best as part of an exercise-based plan.
Can I still go to the gym with shoulder pain?
Usually, yes, with changes. Keep training your legs and core, and adjust upper-body exercises to a pain-free range and load. Your physio can help you swap aggravating exercises for ones that build the shoulder back up.
This article is general information, not a substitute for an individual assessment.
Sources
- Pieters L, et al. An update of systematic reviews examining the effectiveness of conservative physical therapy interventions for subacromial shoulder pain. J Orthop Sports Phys Ther 2020;50(3):131–141. https://doi.org/10.2519/jospt.2020.8498
- Beard DJ, et al. Arthroscopic subacromial decompression for subacromial shoulder pain (CSAW): a multicentre, pragmatic, parallel group, placebo-controlled, three-group, randomised surgical trial. Lancet 2018;391(10118):329–338. https://doi.org/10.1016/S0140-6736(17)32457-1
- Barrett E, et al. Is thoracic spine posture associated with shoulder pain, range of motion and function? A systematic review. Man Ther 2016;26:38–46. https://doi.org/10.1016/j.math.2016.07.008
- Teunis T, et al. A systematic review and pooled analysis of the prevalence of rotator cuff disease with increasing age. J Shoulder Elbow Surg 2014;23(12):1913–1921. https://doi.org/10.1016/j.jse.2014.08.001
Related: Rotator cuff injury · Shoulder impingement · Shoulder pain physio · Strength training in physio · All conditions we treat
Reviewed by Nick Chatziviltsos, PgDip, HCPC-registered physiotherapist (PH114351).