The shoulder is a complex ball-and-socket joint that allows for an extraordinary range of motion. Stability is maintained by the rotator cuff, a group of muscles and tendons. Rotator cuff injuries are common, often leading to significant pain and disability. Understanding the nature of a full-thickness tear is the first step toward effective treatment and recovery.
Anatomy and Defining a Full Thickness Tear
The rotator cuff is composed of four muscles—the supraspinatus, infraspinatus, teres minor, and subscapularis—and their corresponding tendons that surround the head of the humerus (upper arm bone). These four structures stabilize the shoulder joint, keeping the humerus centered in the socket, and allow the arm to rotate and lift. The supraspinatus tendon is the most frequently injured, playing a primary role in lifting the arm away from the body.
A full-thickness rotator cuff tear is a complete discontinuity of the tendon, meaning the tissue has been severed all the way through its thickness. This results in a complete separation of the tendon from its attachment point on the bone, often creating a hole or gap. This type of tear is distinct from a partial-thickness tear, where the tendon is damaged but remains connected to the bone. The complete separation significantly impairs the tendon’s ability to transmit force, leading to pronounced weakness and functional loss.
Common Causes and Risk Factors
Full-thickness rotator cuff tears result from two primary mechanisms: acute trauma or chronic degeneration. An acute tear occurs suddenly, often due to a traumatic event such as falling onto an outstretched arm or lifting a heavy object with a jerking motion. Acute tears cause immediate, intense pain and rapid loss of function.
The more common cause is chronic degeneration, where the tendon gradually wears down over time. Age is the most significant factor, with the prevalence of tears increasing dramatically in individuals over 40.
Chronic degeneration is influenced by several risk factors:
- Repetitive overhead activities, common in sports like baseball pitching or occupations like painting, which place constant stress on the tendons
- Reduced blood supply to the tendons, particularly with age, which weakens tissue and hinders its ability to repair damage
- Smoking
- A family history of shoulder problems
Recognizing the Symptoms and Confirming Diagnosis
The symptoms of a full-thickness tear commonly include pain, weakness, and restricted movement in the shoulder. Pain often intensifies when trying to lift or rotate the arm, and it is worse at night, particularly when lying on the affected side. Some people also report a grinding, clicking, or crackling sensation (crepitus) when moving the shoulder.
Diagnosis begins with a thorough physical examination, assessing the range of motion and testing the strength of the rotator cuff muscles. The physician may perform specialized tests, such as the drop-arm test, which can indicate a significant tear in the supraspinatus tendon. Imaging studies are then used to confirm the diagnosis and determine the tear’s severity.
X-rays can show associated bone spurs or arthritis, but they cannot visualize the soft tissues of the rotator cuff. Magnetic Resonance Imaging (MRI) is the most accurate imaging modality for confirming a full-thickness tear, as it clearly shows the extent of tendon separation and retraction from the bone. Ultrasound is also a reliable, non-invasive option for visualizing the tendon and confirming the injury’s full thickness.
Treatment Pathways
The approach to treating a full-thickness rotator cuff tear depends on several factors, including the patient’s age, activity level, tear size, and symptom duration. Initial management often involves non-surgical options, especially for chronic tears in individuals with lower physical demands. Non-surgical treatment focuses on reducing pain and improving function by strengthening surrounding muscles to compensate for the torn tendon.
This conservative management includes rest and activity modification to avoid painful overhead movements. Physical therapy is a central component, involving specific exercises to improve the flexibility and strength of the remaining rotator cuff and scapular muscles. Nonsteroidal anti-inflammatory drugs (NSAIDs) can help manage pain and inflammation. A corticosteroid injection into the shoulder joint may be used to provide temporary pain relief, especially if pain interferes with sleep or physical therapy participation.
When non-surgical treatments fail, or for acute tears in younger, active patients, surgical repair is often recommended. The goal of surgery is to reattach the torn tendon back to its original site on the humerus using sutures and anchors. The most common technique is an arthroscopic repair, which involves making small incisions and using a miniature camera and instruments. This procedure results in minimal trauma to the surrounding tissue.
Surgical Techniques
An open or mini-open repair may be necessary for very large or complex tears, involving a larger incision and a brief detachment of a shoulder muscle to gain better access. Surgery is typically favored for large tears, tears caused by trauma, or in patients whose work or sport requires a high degree of overhead function.
Recovery and Long-Term Outlook
Recovery from a full-thickness rotator cuff tear is a lengthy process that requires commitment to rehabilitation. Following surgery, the arm is immobilized in a sling for four to six weeks to protect the newly repaired tendon while it heals to the bone. During this initial phase, the patient begins passive range of motion exercises, where a therapist moves the arm without the patient engaging the muscles, to prevent stiffness.
The transition to active motion, where the patient moves the arm independently, typically starts around six to eight weeks post-surgery. Strengthening exercises are introduced gradually, often between eight and twelve weeks, as tendon-to-bone healing progresses. Full recovery, including the return to vigorous activities and sports, can take six to twelve months, depending on the tear size and the individual’s healing capacity.
Adherence to the prescribed physical therapy protocol is the most important factor determining a successful outcome. The long-term prognosis after surgical repair is favorable, with success rates often exceeding 90% for small to medium tears. However, factors such as large tear size, poor tendon quality, advanced age, and smoking can increase the risk of the tendon re-tearing. Even with a re-tear, many patients still experience reduced pain and improved function compared to their pre-operative state.