Impingement occurs when there is excessive friction between tissues. In the shoulder, it often happens when the space between the acromion (shoulder blade) and a group of tendons called the rotator cuff increases, leading to excessive rubbing.
Shoulder impingement is often a result of overuse. Frequently using the shoulder can cause the tendons of the rotator cuff to swell, decreasing the joint space. This makes the cuff rub against the acromion, leading to pain, irritation, and inflammation. Shoulder impingement can also be caused by bursitis (inflammation of the bursa). Bursa provides the lubrication for the cuff to slide freely during motion, so inflammation of this tissue leads to issues.
Risk factors include:
Jobs with overhead lifting
Age related (Increasingly common after age 50)
Previous injuries or structural issues of the shoulder
Sports like volleyball, swimming, tennis, and baseball, as well as occupations like construction, painting, and window washing may increase the risk of this injury. Inflammation or structural issues such as an abnormally shaped acromion can also contribute to impingement.
Signs and Symptoms
If you have pain, weakness, and stiffness at the shoulder joint, you may be experiencing impingement. This pain may be present during a variety of overhead activities, and may even ache at night. Impingement is related to a variety of conditions of the shoulder including bursitis and rotator cuff tendonitis. Dr. Urband will consider these other conditions in the diagnosis of your pain.
Your provider will take your medical history and provide a physical exam including assessing your range of motion. Additional imaging with X-ray, US or MRI may be useful to determine the underlying pathology. In some cases, an anesthetic injection into the acromioclavicular or bicipital groove may be used to provide additional diagnostic information of the underlying source of pain.
Treatment of impingement depends on three majors factors: the underlying pathology, the level or sport/activity and the severity of impingement.
Most patients with impingement symptoms can be treated non-operatively with activity modification, OTC topical and oral analgesics and anti-inflammatories and physical therapy. Other non-operative modalities such as therapeutic ultrasound, electrical stimulation, cold laser therapy and transcutaneous nerve stimulation may also be used.
Injury prevention through stretching and strengthening are the mainstay of treatment for athletes with impingement due to rotator cuff or biceps tendon pathology.
Surgical management may be considered after prolonged failure of non-operative measures or if instability of the shoulder is present. Diagnostic and therapeutic arthroscopy can be performed. Common surgical procedures that may be performed may include subacromial decompression, bursectomy or rotator cuff repair.
There are a few methods of surgery for this condition. Surgeons may widen the subacromial space so the rotator cuff no longer catches on bone. Your provider may also remove an inflamed part of the bursa, or perform an anterior acromioplasty, where part of the shoulder blade is removed. Surgery can be performed arthroscopically or via open surgery.