Did you know that 45% – 65% of all shoulder pain cases are caused by shoulder impingement? Additionally, 50% of people with shoulder pain report persistent symptoms after 3 years. Many people are living with chronic shoulder pain potentially due to shoulder impingement. Shoulder impingement is a condition that results from a structural narrowing of the subacromial space. The subacromial space is the space between the bones of the shoulder (head of humerus and acromion) and the ligament holding them together (coracoacromial ligament). A narrowing of this space causes the tendons of the shoulder muscles (rotator cuff) and these structures to touch. Friction from the rotator cuff tendons rubbing can become extremely painful and cause shoulder impingement.
Inside the subacromial space, you can find several structures including the tendons and muscles of the rotator cuff, as well as the subacromial bursa. Bursa are fluid-filled sacs that reduce friction between bone and soft tissues. Shoulder impingement usually develops when the rotator cuff becomes injured or irritated during movements like shoulder abduction, forward flexion, and internal rotation. This irritation is often accompanied by swelling. This swelling causes the already small space between the acromion and the rotator cuff to become even smaller. The rotator cuff is then more likely to rub on the acromion. This rubbing causes more swelling which promotes further narrowing of the subacromial space.
Bone spurs can also develop and contribute to shoulder impingement. These spurs alter the shape of the acromion and make it more likely to rub against the rotator cuff. Some people may also have an acromion that is not flat due to genetics. This can predispose one to have a higher likelihood of getting a shoulder impingement.
There are 3 main stages of shoulder impingement:
- Stage 1: This stage is characterized by swelling and hemorrhage due to overuse of the shoulder.
- Stage 2: This stage is characterized by more fibrosis and potentially irreversible tendon changes to the rotator cuff.
- Stage 3: This stage includes a possible rupture and tear of the tendons due to chronic and long-standing fibrosis.
Risk factors of shoulder impingement include:
- Participation in overhead sports that involve rotation of the shoulder joint like swimming, baseball, volleyball, and tennis.
- Having an acromion that is “hooked” in shape. This is a genetic defect that can cause Stage 1 impingement.
- Constant manual labor in overhead positions. Those who work as carpenters, hairdressers, painters, and window washers should take heed to use equipment to help wherever possible.
- Those who partake in heavy lifting very often.
- An infection near the shoulder area.
- Fluoroquinolone antibiotics
Now that we have covered the risk factors of shoulder impingement, let’s discuss what are the symptoms of this condition:
- Pain: Shoulder impingement syndrome is usually accompanied by pain when:
- The arm is raised in an overhead position
- When the arm is lifted or lowered or with reaching
- When you try to reach behind the back
- The pain may move from the front of the shoulder to the side of the arm
- Pain with laying on your arm
- The pain may worsen at night and affect your ability to sleep
- There may be tenderness at the front of the shoulder
- Weakness and/or stiffness: This can develop over weeks and months as the condition progresses.
- Increased age, especially in people over 60
If you are experiencing these symptoms, you can visit your doctor or a licensed healthcare professional. The clinician will take a detailed medical history and ask you questions about the types of activities you perform at work or for recreation. They will also ask if you had any previous shoulder injuries. Lastly, they will ask how long you’ve had shoulder pain, and what makes your arm feel better or worse. After this history is taken, the clinician will then physical examine your shoulder where they test the shoulder’s range of motion and strength. They will also examine the shoulder for any tender areas. If impingement is suspected, the doctor may also request diagnostic studies such as:
- Imaging tests such as X-rays to check for the presence of bone abnormalities (like bone spurs), MRIs, and ultrasounds.
- Injections of painkillers or anesthetics into the subacromial space. If the pain is reduced with the injection of these analgesics, it will assist in solidifying if the condition is shoulder impingement.
Once it is confirmed that you are suffering from shoulder impingement, your clinician will develop a treatment plan that may contain routine injections of corticosteroids into the subacromial space. Physiotherapy will also be recommended as a licensed physio can prescribe exercises to strengthen the shoulder and improve flexibility. Here are some things you can do, however, to avoid this condition and stop shoulder impingement syndrome today!
- Avoid repetitive, overhead activities: Those with jobs that require them to make repetitive overhead motions like construction workers should opt to use equipment, like dollies and rolling carts, whenever possible.
- Kick the smoking habit: Smoking is bad for your health overall. It restricts blood flow and prevents your body from getting proper nutrition.
- Avoid heavy lifting: Frequent heavy lifting also increases the chances of getting this condition due to overuse and overload of the shoulder muscles. Be sure to get assistance in a 2 person lift when needed and to utilize correct lifting techniques as appropriate.
- Control inflammation with rest and ice: You can use the R.I.C.E. method which has been shown to reduce rates of inflammation.
- Engage in balance training of the shoulder: A licensed physiotherapist can prescribe exercises that both strengthen the shoulder and improve its flexibility.
- Practice good posture: Bad posture can cause a misalignment of the joints and potentially cause shoulder impingement to develop.
Feel free to incorporate these tips in your daily life to keep those joints healthy for a lifetime.