Rotator Cuff Tear

The rotator cuff is a group of four tendons (supraspinatus, infraspinatus, teres minor, and subscapularis) that wrap around the humeral head and hold it centered in the glenoid. They are the muscles that let you raise, rotate, and control the arm with precision. When one tears, the arm loses its coordinated pull and the shoulder can no longer position itself reliably against gravity. Most tears involve the supraspinatus, the tendon that runs across the top of the joint, and range from partial fraying to complete detachment from the bone.

Tears divide into two patterns. Acute tears follow a single event: a fall onto the arm, a heavy lift, or a shoulder dislocation in a younger patient. Degenerative tears accumulate over years as the tendon thins and frays under repeated use, typically in middle-aged and older adults. After age 60, a torn rotator cuff seen on imaging often represents normal wear rather than a true injury, which is why the symptoms and the findings must be interpreted together.

The supraspinatus (the tendon that runs across the very top of the shoulder) passes through a narrow channel between the ball of the arm bone below and the bony shelf of the acromion above. Every time you lift your arm, the tendon gets briefly squeezed in that channel. Years of this gradual pinching (impingement), combined with the normal wear of aging, can thin and weaken the tendon until a relatively small force tears what is left.

Tear size matters a great deal for decisions about treatment. Small tears behave very differently from large ones where the tendon end has pulled far back into the shoulder and the muscle above has thinned and filled with fat. Your age, how active you are, and which arm is involved all factor into whether repair or non-operative care makes more sense. MRI gives the clearest picture of all of those things.

• Pain on the outer shoulder and upper arm, often worse at night and with overhead activity
• Weakness lifting your arm away from your body or reaching overhead
• Difficulty sleeping on the affected side
• Pain reaching behind your back (tucking a shirt, fastening a bra, grabbing a seatbelt)
• A grinding or popping sensation with shoulder movement

Your provider tests each tendon by asking you to move your arm in specific directions against gentle resistance; weakness in a particular movement pattern points to which tendon has torn. When you are weak far beyond what the pain alone would explain, that suggests a structural tear rather than inflammation.

Plain X-rays check whether the ball of the humerus has ridden upward (a sign of a large longstanding tear) and look for bone spurs or calcium deposits. MRI is the main imaging test: it shows how thick the tear is, how far the tendon end has pulled back, and how much the muscle has thinned, all of which help decide whether repair is the right move.

The thing most patients are surprised to hear: structured physical therapy is the starting point for most rotator cuff tears, including many complete ones. Most people who commit to a genuine course of therapy get lasting relief without surgery, even when imaging still shows the tear. The measures below are usually introduced in order, each added on top of the one before rather than instead of it.

The First-Line Plan

When Surgery Comes Into Play

Surgery comes into play for complete tears in active patients where the weakness is limiting daily life, for tears that have not improved after a real effort at therapy, and for large tears that are at risk of getting worse if left alone. In patients with very large tears that can no longer be repaired and arthritis in the joint, a reverse shoulder replacement can restore overhead function by using a different set of muscles (the deltoid) rather than relying on the damaged cuff.

The Procedures We Consider

After rotator-cuff repair, recovery is deliberately slow; tendon healing to bone takes time, and rushing it puts the repair at risk. The early phase uses a sling with gentle, passive motion only; active use of the arm is held back until healing is established. Active-assisted and then active motion come next, followed by progressive strengthening. Return to overhead work, heavy lifting, and sport is the final phase and depends on how the repair has healed.

Structural healing rates depend on tear size, tissue quality, and patient age. Many patients feel well even when imaging shows incomplete healing; symptomatic outcomes often exceed structural outcomes. Your OSI provider advances you through each phase based on exam and comfort, not on a fixed calendar.

External patient-education references and related OSI pages for additional background:

• AAOS OrthoInfo, patient education library
• OSI glossary, orthopedic terminology in plain language