The shoulder is one of the largest and most complex joints in the body, where many muscles act to provide the widest range of motion of any part of the body. This flexibility is also what makes the shoulder prone to instability and injury.
The shoulder joint is formed where the humerus (upper arm bone) fits into the scapula (shoulder blade), like a ball and socket. The clavicle (collarbone) extends across the front of the shoulder from the sternum to the scapula and helps stabilize the shoulder’s movements.
WHAT IS SHOULDER IMPINGEMENT?
Shoulder impingement is a common cause of shoulder pain. The rotator cuff sits under the top of the shoulder, which is called the acromion. If you have shoulder impingement, your rotator cuff catches or rubs against the acromion. When you lift your arm to shoulder height, the space between the acromion and rotator cuff narrows, which increases pressure. The increased pressure irritates the rotator cuff, leading to impingement.
WHAT ARE THE SYMPTOMS OF SHOULDER IMPINGEMENT?
Symptoms of shoulder impingement include:
- Pain in your shoulder when you lift your arm overhead or backward
- Pain that goes from the front of your shoulder to the side of your arm
- Shoulder / arm muscle weakness
- Pain that gets worse at night
WHAT ARE THE CAUSES AND RISK FACTORS OF SHOULDER IMPINGEMENT?
Many cases of shoulder impingement are due to overuse. Repeated use of the shoulder can make the tendons in your shoulder swell, leading them to “catch” on your upper shoulder bone.
Risk factors of shoulder impingement include:
- Playing sports that require repeated overhead shoulder motions eg. Tennis, swimming, weightlifting
- Occupations that involve heavy lifting and repeated arm movement eg. Painting, construction work
- If you have previously experienced shoulder injuries
- Having an abnormally-shaped acromion
WHAT IS THE DIAGNOSIS OF SHOULDER IMPINGEMENT?
Your Doctor will first check on the medical history of the injury, before conducting a physical examination of your shoulder. Your doctor will then ask you to do a series of motions using your shoulder while checking for any unusual movement. This will also help your doctor rule out other conditions, such as a pinched nerve.
Imaging tests such as an x-ray may be ordered to rule out arthritis or to check for bone changes, such as a spur, which could lead to impingement.
WHAT ARE THE TREATMENT OPTIONS FOR SHOULDER IMPINGEMENT?
At Cove Orthopaedic Clinic, nonsurgical treatments are always the first line of treatment. This includes:
- Resting at home
Avoid strenuous exercise, overhead activities or any movements that make the pain worse.
- Application of ice packs on your shoulder to reduce pain or swelling
Over-the-counter or prescription non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen may be prescribed by your doctor to relieve pain and swelling of the shoulder joint.
The aim of physiotherapy is to rebuild strength and restore motion to your shoulder. Your physiotherapist will give you a series of gentle stretching exercises, which can also be done at home.
- Steroid injections
Should the above methods not work, a corticosteroid such as cortisone can be injected into the bursa beneath the acromion can relieve pain
Should these nonsurgical methods fail to relieve pain, surgery may be recommend. The aim is to widen the space around your rotator cuff, so that it can move freely without catching or rubbing on your bone. This is done via minimally invasive arthroscopic surgery, or open surgery.
- Minimally invasive arthroscopic surgery
Two or three small puncture wounds around your shoulder, and small surgical instruments are inserted into your shoulder. Your doctor will examine your shoulder using a fibreoptic scope connected to a television camera, where he guides the small instruments using a video monitor and removes bone and soft tissue. Most of the time, the front edge of the acromion is removed along with some of the bursal tissue.
- Open surgical technique
This involves a small incision made in the front of your shoulder, allowing your doctor to see the acromion and rotator cuff directly.
In advanced cases of shoulder impingement, you also experience a rotator cuff tear, which requires surgery as well.
RECOVERY AFTER SURGERY
Similar to most shoulder surgeries, your arm will be put in a sling to keep the shoulder in place. Your doctor will let you know when you can remove the sling and start using the arm.
Shoulder impingement usually takes about three to six months for it to completely heal, but more severe cases can take up to a year to heal.