Impingement syndrome (subacromial impingement syndrome) refers to compression of muscles, tendons or nerves under the acromion, the so-called subacromial space. Clinically indicative is night pain and pain at rest, often in combination with pain on movement, in a certain functional area of the shoulder.
This results in dysfunction of the shoulder joint because this range of motion is avoided. Rest, painkillers and targeted physiotherapy can alleviate the initial symptoms of impingement syndrome. However, further clarification is required, as there are several causes that lead to this widespread syndrome. Surgery, if necessary, can prevent permanent joint stiffness.
The key region is the subacromial space, i.e. the space between the humeral head (the “ball”) and the acromion (the “shoulder roof”). This is where the tendons of the rotator cuff cap, which sits on the shoulder ball like a cap, normally glide. This gliding is made possible by a large fish bladder-like bursa, which changes as part of a non-specific inflammation - i.e. it increases in thickness and stores more fluid. This causes the typical symptoms!
The following forms of impingement have been proven:
In the early stages, impingement syndrome is characterized by an acute onset of pain. At rest, it only manifests itself discreetly, but it intensifies during strenuous activities, especially if these are performed above the head. In many cases, patients can identify a triggering event. Extraordinary strain during activities above the head or the influence of cold are often associated with the onset of pain. The pain in impingement syndrome is described as being deep in the joint, but also on the side of the upper upper arm. In addition, lying on the affected side is described as extremely uncomfortable. In all cases, the cause is non-specific inflammation of the bursa.
The inflammation of the bursa can lead to adhesions and adhesions, which further increase the painful restriction of movement.
A relieving posture also often leads to muscle atrophy due to the lack of movement, which further reduces the function of the shoulder joint.
The late stage is a stiff, painful shoulder. The function of the shoulder is severely restricted and the quality of life is significantly reduced.
Around 10% of the population suffer from shoulder impingement syndrome. Athletes who perform overhead movements with their arms, such as handball and volleyball players, swimmers, javelin throwers and bodybuilders, are most frequently affected. This painful shoulder condition is just as common in people who perform overhead work.
The general principle for impingement syndrome is: the earlier treatment begins, the better the chances of recovery. Depending on the stage of degeneration (wear and tear) and the associated symptoms, various conservative treatment methods can be considered: rest, painkillers and targeted physiotherapy can alleviate the initial symptoms of impingement syndrome. Shock wave therapy can also alleviate the pain.
If conservative treatment does not improve the symptoms within six months or if the condition of the tendon worsens, surgery is often the only way to alleviate the symptoms. This surgical procedure is known as subacromial decompression.
Dr. Martin Schwarz, MSc, Prim. a.D.
Specialist for trauma surgery,
Specialist in Orthopedics and Traumatology Shoulder Center Vienna
Surgery for shoulder, knee and sports injuries