Shoulder impingement syndrome accounts for 44 to 65% of all consultations for shoulder pain. If you feel pain when you raise your arm between 60 and 120 degrees, you may be one of the thousands of Quebecers affected each year.

Here's the good news: impingement syndrome responds very well to conservative treatment. Your shoulder is more adaptable than you think, and 70% of people see significant improvement with physical therapy.

You will discover what really causes this syndrome, how to recognize it, and how physical therapy can help you regain a pain-free shoulder.

What is shoulder impingement syndrome?

Impingement syndrome occurs when the rotator cuff tendons and subacromial bursa become trapped in the subacromial space—the area between the head of the humerus and the acromion (the part of the shoulder blade that forms the roof of the shoulder).

Imagine this space as a narrow tunnel through which your tendons pass every time you raise your arm. When this space narrows or the structures become inflamed, repeated friction causes irritation and pain.

The rotator cuff is a group of four muscles that stabilize the shoulder. The tendons most commonly affected are those of the supraspinatus and infraspinatus. The subacromial bursa acts as a cushion between the acromion and the tendons, reducing friction.

Impingement syndrome particularly affects people aged 40-60. Now that you understand the structures involved, let's look at how to differentiate this syndrome from other shoulder problems.

How can you tell the difference between impingement syndrome and other shoulder problems?

Impingement syndrome describes a mechanical problem (subacromial compression), while rotator cuff tendinopathy describes a problem with the tendon tissue. Repeated impingement can cause tendinopathy, and vice versa—the two often coexist.

Subacromial bursitis is often a consequence of impingement syndrome. Repeated irritation of the bursa causes it to become inflamed and thickened, further reducing the available space.

Capsulitis (frozen shoulder) is characterized by severe loss of mobility in all directions, whereas snapping syndrome causes pain in a specific arc without major loss of passive mobility.

Each condition requires a tailored approach. Let's now explore the characteristic symptoms.

What are the symptoms of shoulder impingement syndrome?

The most telling symptom is the painful arc: pain when you raise your arm between 60 and 120 degrees. Paradoxically, the pain often decreases beyond 120 degrees, once the compressed structures are out of the pinching zone.

The pain is located at the front or top of the shoulder and may radiate to the elbow. It is described as a pinching sensation during movement. At rest, it may be absent in the early stages but becomes constant in chronic cases.

Nighttime pain is particularly common. Many report waking up at night, especially when sleeping on the affected shoulder.

Typically painful tasks:

• Wash or dry your hair
• Put your hand behind your back (fasten your bra, take out your wallet)
• Store items high up
• Put on a coat
• Playing sports with your arms raised (tennis, volleyball, swimming)

The syndrome develops gradually over several weeks or months. Sudden pain after trauma suggests an acute tear.

If you recognize these symptoms, you are probably wondering what is causing them.

What REALLY causes shoulder impingement syndrome?

Many believe that impingement syndrome is caused by a "hooked" acromion or a "lack of natural space"—an anatomy that cannot be changed. This view is discouraging because it suggests that you are doomed by your bone structure.

Here's the reality: although anatomy plays a role (30% have a hooked acromion), the majority of impingement syndromes are caused by functional factors that can be modified with the right treatment.

Your shoulder blade must move in sync with the humerus. If the shoulder blade does not move correctly—due to weak muscles (lower trapezius, serratus anterior) or tight muscles (pectoralis minor)—the subacromial space is reduced and the tendons become pinched. It's like a door with misaligned hinges: it rubs against the frame.

The rotator cuff muscles center the head of the humerus in the joint. If some are weakened (supraspinatus, external rotators) while others are tense (deltoid, pectoralis major), the head of the humerus migrates upward and reduces the space.

A loss of flexibility in the posterior joint capsule forces the head of the humerus to migrate forward and upward, increasing subacromial compression.

A posture with the head thrust forward and rounded shoulders tilts the shoulder blade forward, reducing the subacromial space. If you work at a computer for long periods of time, this posture can contribute significantly to this problem.

Approximately 30% have an acromion whose shape naturally reduces the space. However, this does not necessarily mean that the syndrome will develop—only if other functional factors are added.

If your syndrome were solely due to your bone anatomy, there would be nothing you could do without surgery. But since the majority of cases are primarily functional, you can improve your condition by correcting muscle imbalances, posture, and movement patterns—exactly what physical therapy does.

You are not "broken." Your shoulder needs to relearn how to move properly.

How is shoulder impingement syndrome diagnosed?

The diagnosis is based on clinical assessment by a qualified professional. Your physical therapist can make this diagnosis without first consulting a doctor.

Questions about: onset and progression of symptoms, activities that cause or relieve pain, nighttime pain, work and sports activities.

Specific tests reproduce the characteristic pain:

• Neer test: Passively raise your arm in internal rotation.
• Hawkins-Kennedy test: Arm bent at 90 degrees then turned inward
• Painful arc test: Actively raise the arm to identify the painful area.

Assessment of muscle strength, joint mobility, and scapular movement analysis.

Clinical evaluation is usually sufficient. Imaging is recommended if: no improvement after 12 weeks of physical therapy, suspicion of complete tear, recent trauma.

Important: Many asymptomatic individuals show abnormalities on imaging. Their presence does not mean that they are causing your pain.

Now let's see what physical therapy can do.

What is the physiotherapy treatment for snapping syndrome?

Physical therapy is the first line of treatment, with a 70% success rate. The approach restores normal function by addressing the functional causes.

For a comprehensive guide, see our article on physical therapy for shoulder pain.

• Reduce pain and inflammation
• Restore range of motion
• Correct muscle imbalances
• Improve neuromuscular control
• Change postural habits
• Prevent recurrence

Joint mobilization to restore mobility and reduce pain. Relaxation of tense muscles (pectoralis minor, upper trapezius). Capsular stretching for posterior capsule flexibility.

Studies show that manual therapy combined with exercises yields better results than exercises alone.

Pendulum exercises, gentle stretching, basic scapular mobility, temporary avoidance of very painful movements.

Strengthening of the rotator cuff in pain-free areas, strengthening of the scapular muscles (lower trapezius, serratus anterior), neuromuscular control exercises.

Weight-bearing exercises, specific functional exercises, progression to overhead movements, prevention of recurrence.

How to temporarily modify activities, compensatory strategies, good work posture and sleep, appropriate balance of activities.

Significant improvement in 6 to 12 weeks. Chronic cases require more time.

Factors accelerating recovery: early consultation, adherence to exercises, modification of aggravating activities.

If there is no response after 3 to 6 months of proper physical therapy: corticosteroid injection, thorough medical evaluation.

Remember that 70% improve with physical therapy alone. Patience and consistency in exercising are your best allies.

What exercises can you do at home for snapping syndrome?

Home exercises are essential. Here are some basic exercises, but consult a physical therapist who will tailor the program to your situation.

Lean forward, placing your healthy hand on the table. Let your sore arm hang freely. Make small circles in each direction (10 repetitions). Swing forward and backward, then left and right. Frequency: 3-4 times a day.

Forearm against door frame (elbow at 90 degrees). Move your foot slightly forward, turn your body in the opposite direction. Hold for 30 seconds, repeat 3 times. Frequency: 2-3 times per day.

Lie on your painful side with your arm at a 90-degree angle in front of you. With your other hand, gently push your hand down. Hold for 30 seconds and repeat three times. Frequency: twice a day.

Elastic band at elbow height. Elbow pressed against the body, bent at 90 degrees. Pull the elastic band outward. 3 sets of 12-15 repetitions. Frequency: once a day, 5-6 days/week.

Elastic band in front of you at chest height. Pull your elbows back and bring your shoulder blades together. 3 sets of 12-15 repetitions. Frequency: once a day.

Stand facing the wall, arms in a "soccer goal" position. Slide your arms up along the wall. 3 sets of 10 repetitions. Frequency: once a day.

A physical therapist will identify the exercises that are most important for your situation.

How can shoulder impingement syndrome be prevented?

Prevention is based on simple but effective strategies.

Regular strengthening of the rotator cuff (2-3 sessions/week with elastic bands). Strengthening of the scapular muscles (lower trapezius, serratus anterior). Stretching of the anterior muscles (pectoralis minor, pectoralis major).

At work: monitor at eye level, armrests to support arms, frequent breaks (every 30-45 minutes).

General posture: "grow" steadily—chin tucked in, shoulder blades slightly down and back. This position optimizes subacromial space.

Lifting objects overhead: raise your shoulders slightly before lifting. Sports involving repeated overhead movements: adequate warm-up, appropriate technique, gradual progression in volume (10% rule).

Avoid sleeping on the painful shoulder or placing your arm under the pillow. When sleeping on your side, place a pillow between your arms to support your upper shoulder. Ensure your neck is well supported.

Gradual progression if resuming activity after a break. Respect pain signals: slight stiffness after new activity = normal. Pain persisting for more than 24 hours = too much.

Thoracic mobility: extensions on foam roller, thoracic rotations. Posterior capsule mobility: sleeper stretch 2-3 times/week, even after recovery.

What is the prognosis for shoulder impingement syndrome?

The prognosis is generally good with appropriate treatment.

Approximately 70% of people treated with physical therapy report significant improvement.

Syndrome aigu (<3 mois) : Amélioration notable en 4-6 semaines. Récupération complète en 8-12 semaines. Pronostic excellent.

Chronic syndrome (>6 months): Significant improvement in 8-12 weeks. Full recovery in 3-6 months or more. Good prognosis, but slower.

If left untreated, chronic irritation can progress according to Neer's model:

This increase highlights the importance of early treatment, before permanent damage occurs.

Approximately 40% report persistent or recurring symptoms after 3 years. However, this rate often reflects: incomplete recovery, return to aggravating activities without modification, absence of a maintenance program.

People who complete the full program and now do maintenance exercises have a much lower relapse rate.

Most impingement syndromes resolve with proper conservative treatment. The key is patience, consistency in exercises, and collaboration with a physical therapist.

You don't have to live with this pain. Your shoulder can heal and regain full function.

When should you seek medical advice for shoulder impingement syndrome?

Consult if:

• Persistent shoulder pain lasting >7–10 days despite rest
• Characteristic painful arc (60-120 degrees)
• Nighttime pain that regularly wakes you up
• Pain limiting daily activities

In Quebec, you do not need to see a doctor before consulting a physical therapist.

Consult a doctor immediately if:

• Shoulder pain with chest pain, shortness of breath (call 911)
• Pain after significant trauma
• Sudden and marked loss of strength
• Persistent numbness in arm and hand
• Pain with fever, chills, redness, or intense heat
• History of cancer

• No improvement after 12 weeks of physical therapy
• Progressive worsening despite treatment

The longer you wait, the more likely the syndrome is to become chronic. If you are unsure, consult your doctor.

To explore all treatment options, check out our comprehensive guide to shoulder pain.