What Is Shoulder Pain?
Shoulder pain is the third most common musculoskeletal complaint after back and neck pain. The most frequent cause is rotator cuff-related shoulder pain — an umbrella term that includes what used to be called “impingement”, “tendinitis”, “bursitis” and partial cuff tears.
A second common picture is frozen shoulder (adhesive capsulitis), where pain is followed by progressive stiffness over months. Frozen shoulder almost always recovers, but the timeline is long — typically 18 months to 3 years.
Modern evidence has shifted away from quick surgery for most rotator cuff problems. Progressive exercise is the first-line treatment for both rotator cuff-related pain and frozen shoulder, with injections and surgery reserved for specific situations.
Common Causes
- Rotator cuff-related pain (Common): Pain on the outside of the upper arm, worse with overhead or behind-back movement. Often called impingement or tendinopathy.
- Frozen shoulder (Common): Painful loss of motion in all directions. Three phases: freezing, frozen, thawing — usually 18–36 months total.
- Acromioclavicular joint pain (Specific): Pain at the top of the shoulder where the collarbone meets the shoulder blade — often after a fall or with bench press.
- Labral tear (Specific): Pain with throwing or overhead activity, often with clicking or “dead arm” feeling.
- Calcific tendinopathy (Inflammatory): Sudden, severe shoulder pain caused by calcium deposits in the rotator cuff tendons.
- Referred pain (Referred): Neck, heart, gallbladder, and diaphragm problems can all refer pain to the shoulder.
Treatments
- Short-course NSAIDs for acute flares
- Subacromial or glenohumeral corticosteroid injection (selective use)
- Hydrodilatation for frozen shoulder
- Surgery (subacromial decompression, cuff repair) — selective indications
- Progressive loading program (heavy slow resistance has best evidence)
- Range of motion in frozen shoulder — pacing not forcing
- Manual therapy as adjunct to exercise
- Education on activity modification
- Return-to-sport or return-to-overhead-work programs
- Pacing strategies in chronic shoulder pain
- Sleep optimisation (shoulder pain disturbs sleep, which worsens pain)
- Stress and mood support — anxiety predicts persistence
Red Flags — When to Seek Care Now
- Shoulder deformity after trauma — possible fracture or dislocation
- Sudden, complete inability to lift the arm after injury
- Shoulder pain with chest pain, sweating, or shortness of breath (possible cardiac)
- Shoulder pain with fever, swelling, redness — possible infection
- Unexplained weight loss or known cancer with new shoulder pain
Dos and Don’ts
- Keep using the shoulder within tolerable pain
- Do progressive loading exercises — under guidance
- Sleep with a pillow under the affected arm to offload the joint
- Address neck and shoulder-blade mobility, not just the joint itself
- Be patient — rotator cuff recovery often takes 3–6 months, frozen shoulder longer
- Don’t use a sling for non-traumatic shoulder pain
- Don’t repeatedly seek injections without an exercise plan
- Don’t push painful end-range stretches in a frozen shoulder
- Don’t rush back into overhead loading too soon
Frequently Asked Questions
Why does my shoulder hurt at night?
Lying on the shoulder compresses inflamed tendons and bursa; the tendons also have lower blood flow at rest. Pillows under the arm and side-sleeping on the opposite side help most.
How long does frozen shoulder last?
On average 18–36 months from start to full recovery. Pain peaks early; stiffness peaks in the middle; motion gradually returns. Most people recover fully.
Is surgery better than exercise for rotator cuff problems?
For atraumatic rotator cuff-related shoulder pain, structured exercise produces similar long-term outcomes to surgery in most studies, with fewer risks. Surgery is more clearly indicated for full-thickness traumatic tears in active patients.
Educational use only. This content summarises peer-reviewed research and is not a substitute for personalised medical advice.