Shoulder Impingement Syndrome is a term used to describe pain and inflammation in the front and outside of the shoulder, which is a result of repetitive micro-traumas to the rotator cuff (supraspinatus tendon), biceps tendon, or subacromial bursa. All of these structures are considered to be “soft” tissue.  In an efficient shoulder, when the arm is lifted overhead, the head of the humerus moves lower within the joint, providing more space for the soft tissue structures to move and slide.  In an inefficient shoulder, this lowering of the humeral head does not occur, and the soft tissues may”impinge” upon, or rub against, the bony/ligamentous coracoacromial arch (formed by a ligament running between the coracoid process and the acromion of the scapula at the top of the shoulder).  Over time this can cause inflammation and degeneration of these structures.  Poor posture, shoulder instabiity, rotator cuff weakness, previous injury, bony deformities, and overhead sports can all increase the likelihood of developing shoulder impingement.

History and Symptoms

Posterior (back) view

• Usually not traumatic, although impingement can occur secondary to other shoulder injuries
• Usually a gradual onset; pain may have been present off-and-on for months or years
• Less commonly new activities can cause onset of pain
• Associated with prolonged overhead activities
• Pain in the front and the outside of the shoulder (sometimes pain may radiate down the arm)
• Pain with lying on the shoulder
• Pain with moving the arm up, out the side, or reaching behind (usually there is a painful arc of motion between ~80-120 degrees)
• Pain is usually sharp in nature and relieved upon cessation of activity

Conservative Treatment

• Ice: icing post-activity helps decrease inflammation and pain
• NSAIDs (Non-Steroidal Anti-Inflammatory Drugs): such as Advil or Aleve.  Always check with your physician before using medication
• Rest/Activity Modification: rest is a critical component of treatment in order to decrease the inflammation incurred through repetitive, exacerbating motions (such as overhead activity).  However, rest in isolation will not solve the structural or biomechanical issues causing the impingement.  These will…
• Transverse Friction Massage: transverse friction massage increases blood flow to the (otherwise hypovascular) rotator cuff tendons, and also increases the mobility and integrity of the tendons.
  
• Rotator Cuff Strengthening: because of pain and/or disuse, the rotator cuff muscles often become inhibited and weak.  This perpetuates the impingement process.

1. Standing Shoulder Internal Rotation: Attach an elastic band to a doorknob (like a Theraband).  Hold one end in your hand.  Stand with your elbow tucked against your side,  your elbow bent to 90 degrees, and your hand facing straight ahead.  Slowly rotate your forearm to your stomach.  Relax and slowly return to the starting position.  External rotation can also be performed using an elastic band.
2. Side-lying Shoulder External Rotation: Lie on your side with your top elbow tucked against your side and your elbow bent to 90 degrees. Slowly rotate your forearm up towards the ceiling, keeping your elbow firmly against your side.  Lower slowly back to the starting position.  Progress to using light dumbells (less than 5 lbs.)
3. Shoulder Scaption: Begin by gently squeezing your shoulder blades together.  This is called “setting your scapulas”.  Holding your shoulder blades together (gently), raise your arm to shoulder height with your thumb facing up.  Make sure your elbows are straight. The angle of this motion should be about 30 degrees to the outside of straight ahead.  This exercise can also be progressed using light dumbells.

• Physical Therapy: A good PT can address posture, muscle strength/coordination, shoulder joint mobility, and other factors related to shoulder impingement that you may not be able to address on your own.