Shoulder Injury: Rotator Cuff Tear - Acute Conditions and Injuries of the Shoulder Joint

The shoulder joint allows the arm to move in multiple directions, making it a highly complex joint. In addition to the shoulder blade and the humerus, the clavicle also plays an important role in the stability and mobility of the shoulder joint. The rotator cuff is responsible for many of these movements.

The rotator cuff is a group of four muscles, known as the rotators. The rotators extend from the scapula to the humerus. Their tendons wrap around the head of the humerus like a cuff. This allows them to rotate the arm.

At the same time, simultaneous contraction of these muscles can press the head of the humerus into the glenoid cavity and stabilize the joint. In addition to enabling movement in various directions, the rotator cuff is therefore also responsible for shoulder stability.

Naturally, this dual role places high stress on the tissue. The rotator cuff is susceptible to damage from both

• brief, intense stress spikes during sports or a fall, as well as
• long-term, highly repetitive stress in everyday life.

A rotator cuff tear is a common condition affecting the shoulder. It refers to a tear in the rotator cuff (ICD code: S46/M75.1).

Typically, the most common injuries involve the tendon, which transmits the force of the moving muscle to the static bone.

These problems range

• from swelling and bruising of the tendons to
• small surface tears
• to complete tears of multiple muscle tendons.

Illustration of the rotator cuff of the shoulder © logo3in1 | AdobeStock

Degeneration and tears of the rotator cuff are therefore usually the reasons for shoulder surgery.

Since many rotator cuff tears do not cause symptoms, they often go undetected. As a result, it is impossible to say with absolute certainty how often such tears occur.

Rotator cuff tears are extremely rare before the age of 40. Their frequency increases with age. One study identified a rotator cuff tear in over 80% of people over the age of 80.

Signs of wear and tear and accidents are the most common causes of a rotator cuff tear. In some cases, there is also an injury to the acromioclavicular joint, which can cause similar symptoms.

The rotator cuff often tears after a fall onto an arm extended backward. If the impact is particularly severe, this can also result in injuries to the elbow or forearm. Such accidents account for 70% of cases and are the most common cause of tears without signs of wear and tear.

However, rotator cuff tears resulting from pre-existing degenerative damage are more common overall. Degenerative changes refer to signs of wear and tear. Overuse of the shoulder due to repeated overhead movements can also lead to a tear over time.

There are also mixed forms in which patients with pre-existing degenerative damage experience a minor accident. This exacerbates the existing defect and triggers symptoms.

Shoulder dislocation in patients over 40 years of age leads to a rotator cuff tear in 40 to 70 percent of cases.

Although the symptoms of a rotator cuff tear are quite distinct, the intensity of pain varies greatly. A large proportion of rotator cuff tears cause no symptoms, particularly in the case of minor degenerative tears. With these slowly developing tears, the shoulder has had enough time to adapt to the problem. Affected individuals often complain of limited shoulder mobility, especially during everyday activities.

Acute massive tears, on the other hand, cause very pronounced symptoms.

The most common shoulder symptoms associated with a rotator cuff lesion are pain, especially during overhead activities. However, the key symptoms of a tendon tear are night pain and reduced strength.

The diagnosis of a rotator cuff tear consists of

• a targeted medical history,
• a clinical examination, and
• imaging studies

.

The clinical examination includes

• assessment of active and passive range of motion in all degrees of freedom and
• isometric strength testing.

In addition, there are specific functional tests. These allow the individual muscles of the rotator cuff to be tested in isolation. However, the reliability of all rotator cuff functional tests can be significantly compromised by pain during the examination.

X-rays in three planes are considered the standard diagnostic tool for pathological changes in the rotator cuff. For this,

• an X-ray with correct adjustment of the joint space,
• the axial view, and
• the Y-view.

Based on these images, changes in the bony joint can be assessed.

Ultrasound examination enables a quick and cost-effective assessment of the rotator cuff. It allows for the diagnosis of simple degenerative changes and complete rotator cuff tears with a high degree of accuracy. At the same time, it is possible to evaluate the long biceps tendon for stability and associated inflammation.

In recent years, magnetic resonance imaging (MRI) has established itself as extremely helpful in shoulder diagnostics. Its accuracy is further enhanced by the intra-articular administration of contrast agents in what is known as contrast-enhanced MR arthrography.

Computed tomography (CT), on the other hand, no longer plays a significant role in rotator cuff diagnostics. Magnetic resonance imaging has largely replaced it. In isolated cases, a CT scan is still used to assess fatty degeneration of the muscle. In cases of unclear findings or persistent symptoms, a specialist in orthopedics should be consulted to determine the exact cause.

The choice of the appropriate treatment depends on the severity of the injury and the individual findings. Treatment options are determined by a variety of factors. These are analyzed in detail and depend on the findings. There is no standardized treatment approach.

Criteria for determining treatment include:

• the patient’s age,
• Cause of the tear,
• the patient’s activity level,
• Type of tear,
• size of the tear,
• tendon quality, and
• muscle quality.

These criteria give rise to numerous treatment options that can be applied depending on the individual case.

In many cases, conservative, non-surgical treatment is a good choice and can yield good results. This can be supported by biological methods such as ACP. Especially in cases of slowly developing, degenerative rotator cuff defects, treatment initially focuses on conservative methods.

However, if no significant improvement occurs within three months, surgery may be necessary.

Rotator cuff tears tend to enlarge over time. Therefore, the success of conservative treatment is usually not permanent. Half of the patients develop new symptoms within 3–5 years and then require surgery.

The treatment of choice for rotator cuff tears today is anatomical reconstruction. It can be performed via

• an open procedure,
• minimally invasive open, or
• purely arthroscopic suturing

.

Due to improved range of motion and reduced tissue trauma, the purely arthroscopic procedure is becoming increasingly prevalent.

The prognosis for healing after a tendon suture depends on the size of the tear. Small tears heal with a high degree of certainty. Moderate and large rotator cuff tears have lower healing rates, ranging from 70 to 80 percent.

However, there are now a number of surgical options available to stimulate biological healing in these cases.

Below is an overview of the procedure for a minimally invasive surgery to treat a rotator cuff tear:

Follow-up care for a rotator cuff tear depends on the type of treatment. After an anatomical reconstruction, the arm must be immobilized for 2–5 weeks. During this time, the tendon can heal and attach to the bone. A simple sling may be sufficient for immobilization. During this time, passive range-of-motion exercises are permitted under the guidance of a physical therapist.

Consistent physical therapy is crucial for restoring shoulder function and achieving long-term stable mobility. Starting in the 7th week after surgery, active range-of-motion exercises and exercises in a pool are possible. In addition, extensive exercises to center the humeral head are required. The total rehabilitation period lasts approximately 12 to 16 weeks.

The restoration of the ability to work after a rotator cuff tear or shoulder dislocation depends heavily on the nature of the job and the level of physical activity involved. Light physical activities that do not involve overhead movements are possible starting from the 5th to 7th week after surgery. Overhead activities are not permitted before the 13th week after surgery. The rehabilitation period is extended overall.

Overhead sports activities should not be resumed until at least 6 months after surgery.

1. What is a rotator cuff tear?
A rotator cuff tear is a tear in one or more of the tendons of the rotator cuff in the shoulder joint. These tendons connect the muscles of the shoulder blade to the upper arm bone and provide stability and mobility to the shoulder.