The rotator cuff is a complex group of four muscles and their corresponding tendons surrounding the shoulder joint. These structures provide dynamic stability and facilitate the wide range of motion necessary for daily activities. A significant injury to one or more of these tendons can result in a specific diagnosis. This article defines the anatomy, causes, symptoms, and treatment pathways for a full thickness rotator cuff tear.
Understanding the Anatomical Severity
A full thickness tear represents a complete discontinuity, meaning a hole has formed that extends entirely through the tendon from the bursal side to the articular side. This is distinct from a partial thickness tear, which involves damage to the tendon fibers but does not breach the entire structure. The severity of a full thickness tear is often classified by its size, such as small, medium, large, or massive, which guides treatment decisions.
The rotator cuff is composed of four distinct tendons that attach the muscles to the humerus (upper arm bone). These include the supraspinatus, infraspinatus, teres minor, and subscapularis. The supraspinatus tendon, which assists in lifting the arm, is the most frequently injured structure in the shoulder. A full thickness tear typically involves the complete detachment of one or more of these tendons from their bony insertion point.
How Full Thickness Tears Happen
Full thickness tears can result from a single, high-energy event known as an acute traumatic injury. This often occurs during a sudden fall onto an outstretched arm or from forcefully lifting an unexpectedly heavy object. Shoulder dislocations can also stretch and tear the tendons, particularly in younger individuals. These acute tears usually require prompt medical attention due to the sudden onset of severe dysfunction.
The majority of full thickness tears, however, develop gradually over time due to chronic degeneration. This process is associated with the natural aging of the tendon tissue, which compromises its structural integrity and tensile strength. Repetitive overhead activities, such as certain sports or occupational tasks, accelerate this chronic wear and tear.
A contributing factor to degenerative tears is mechanical impingement, where bony growths called spurs develop beneath the acromion (outer part of the shoulder blade). These spurs rub against the rotator cuff tendons during arm movement, causing fraying and thinning over many months or years. This chronic mechanical abrasion eventually weakens the tendon fibers sufficiently for a full thickness rupture to occur with minimal force.
Identifying the Symptoms
The primary symptom experienced with a full thickness tear is a profound weakness, particularly when attempting to lift or rotate the arm. Patients often report an inability to actively raise the arm away from the side, a condition sometimes termed pseudoparalysis. This functional deficit occurs because the detached tendon can no longer transmit the necessary force from the muscle to the bone for movement.
Pain is another common complaint, frequently radiating down the arm toward the elbow. Severe night pain is particularly disruptive, often waking the individual or making sleeping on the affected side impossible. Furthermore, some individuals describe a distinct clicking, popping, or catching sensation within the shoulder joint during movement.
Management and Treatment Pathways
Before treatment begins, the severity of a full thickness tear must be confirmed, typically using magnetic resonance imaging (MRI) or ultrasound. These imaging modalities accurately determine the tear size, the degree of tendon retraction, and the quality of the muscle tissue remaining. This confirmation guides the subsequent management pathway, which is highly individualized.
Conservative treatment is often the initial approach for smaller, degenerative tears or when surgery presents too high a risk. Physical therapy focuses on strengthening the remaining rotator cuff muscles and the surrounding shoulder girdle musculature to compensate for the torn tendon. The goal is to maximize stability and improve functional range of motion.
Non-steroidal anti-inflammatory drugs (NSAIDs) can be used to manage pain and reduce inflammation. Corticosteroid injections provide short-term pain relief by reducing inflammation within the shoulder joint. However, these injections are used sparingly, as repeated use may potentially weaken the remaining tendon tissue. Non-operative strategies are appropriate only if the patient’s symptoms improve and functional deficits are tolerable.
Surgery is recommended when conservative measures fail after three to six months, or for large, acutely traumatic tears in active individuals. The primary surgical goal is the anatomical re-attachment of the torn tendon back to its original insertion point on the humerus. Reattaching the tendon re-establishes the functional connection between the muscle and the skeleton.
Most rotator cuff repairs are performed arthroscopically, using small incisions and specialized cameras and instruments. The surgeon uses sutures and anchors to secure the tendon firmly to the bone, promoting biological healing. Post-operative recovery is lengthy, beginning with immobilization (typically four to six weeks) to protect the repair site. This is followed by a structured physical therapy program that progresses from passive range-of-motion exercises to active strengthening over four to twelve months.