Shoulder Pain When Lifting Your Arm? Here's What's Going On

Reaching for something on a high shelf. Putting on a shirt. Lying on your side at night. When your shoulder hurts, these small daily movements become a struggle. If the pain has crept up slowly without any injury, you're dealing with one of the most common shoulder problems there is.
What is subacromial shoulder pain?
Most shoulder pain without an injury comes from the space at the top of the shoulder, under a bony arch called the acromion. The rotator cuff tendons and a small cushion called the bursa sit here. When they become irritated, it's called subacromial pain syndrome. You may have heard it called shoulder impingement.
This accounts for roughly half or more of all shoulder pain, and is most common in people over 40.
Common signs include:
- Pain on the outside of the shoulder
- A painful arc when lifting your arm out to the side, often between shoulder and head height
- Pain reaching overhead or behind your back
- Pain when lying on that side
- Weakness or a tired feeling in the arm
Do you need surgery or an injection?
Usually not. Research shows no convincing evidence that surgery works better than physiotherapy for this condition. Even a rotator cuff tear on a scan is not, on its own, a reason for surgery. Steroid injections are not recommended as a first step.
How physiotherapy helps
Supervised exercise is the first-line treatment, and hands-on therapy adds extra benefit. At Katasi Physiotherapy, your plan may include:
- Rotator cuff strengthening
- Shoulder blade control and posture exercises
- Manual therapy to ease pain and stiffness
- Sleep position advice
- Gradual return to gym, sport and overhead work
Most people need at least 12 weeks of consistent rehab, so we'll set clear goals and track your progress.
Book your assessment
Get your shoulder moving freely again. Book at Katasi Physiotherapy, Mogotio Road off Muthithi Road, Westlands. Call or WhatsApp 0705 717 353.
Source: Physiopedia – Subacromial Pain Syndrome
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