When you tear your rotator cuff, one or more of the tendons connecting your shoulder muscles to your upper arm bone become partially or fully detached. The result is a deep, dull ache in the shoulder, noticeable weakness when lifting or rotating your arm, and pain that often gets worse at night. What happens next depends on the size and type of the tear, but the shoulder does not simply heal on its own the way a cut on your skin would.
The Four Muscles That Hold Your Shoulder Together
Your rotator cuff is a group of four muscles and their tendons that wrap around the ball of your shoulder joint, holding it snugly in its socket while still allowing a wide range of motion. The supraspinatus runs along the top of your shoulder blade and connects to the top of your upper arm bone; it handles lifting and rotating your arm and is the most commonly torn of the four. The infraspinatus and teres minor attach along the back of the shoulder blade and help you rotate your arm outward. The subscapularis sits on the front side and lets you hold your arm away from your body.
Together, these muscles do more than move your arm. They actively stabilize the joint during every push, pull, and overhead reach. When even one tendon tears, the balance of forces around the joint shifts, and the remaining muscles have to compensate.
Partial Tears vs. Full-Thickness Tears
Not all rotator cuff tears are the same. In a partial tear, the tendon is damaged but still attached to the bone. Think of it like a rope that’s fraying but hasn’t snapped. The tendon becomes thinner than normal at the injury site, which weakens it and causes pain but still allows some function.
A full-thickness tear means part or all of the tendon has detached from the bone. If only a portion has pulled away, it’s considered a full-thickness incomplete tear. If the entire tendon separates, it’s a full-thickness complete tear, essentially leaving a hole in the tendon. Full-thickness tears are more likely to cause significant weakness and loss of motion, and they carry a higher risk of long-term structural changes in the shoulder.
What It Feels Like Day to Day
The hallmark symptom is a dull ache deep in the shoulder, not a sharp surface-level pain. It tends to worsen at night, partly because lying on the affected side compresses the injured tissue and partly because the shoulder settles into positions that put tension on the torn tendon. Many people find that sleep disruption is one of the most frustrating parts of living with a tear.
During the day, you’ll likely notice weakness when lifting your arm, especially overhead or out to the side. Everyday tasks become difficult: combing your hair, reaching behind your back to tuck in a shirt, grabbing something off a high shelf. The arm may feel heavy or sluggish rather than acutely painful during these movements. Some people also notice a crackling sensation when they move the shoulder.
What Happens Inside an Untreated Tear
A torn rotator cuff tendon cannot reattach itself to bone. If the tear goes unaddressed, two changes begin inside the shoulder, and both are difficult to reverse.
The first is fatty infiltration. Shortly after a tendon tears or the tear worsens, fat begins replacing normal muscle tissue in the affected muscle. Research published in JSES International found that this fatty replacement happens in the early phase after a tear, sometimes before the muscle has visibly shrunk. Over time, the muscle itself starts to atrophy. Even when a tear doesn’t get larger, the muscle volume continues to decrease gradually. In people with massive tears, this loss is measurable in the supraspinatus and the infraspinatus/teres minor group. Once a muscle fills with fat and shrinks, surgical repair becomes less likely to succeed because the tissue quality is too poor to hold a repair.
The second long-term consequence is a condition called cuff tear arthropathy. Normally, the rotator cuff keeps the ball of the upper arm bone centered in the socket. Without that stabilizing force, the ball migrates upward and grinds against the bony arch above it (the acromion). Over months and years, both surfaces erode. The cartilage wears away, the bone roughens, and the shoulder develops a severe form of arthritis that progressively destroys the joint. This condition does not improve on its own and, once advanced, may require a specialized joint replacement rather than a standard repair.
Many Tears Cause No Symptoms at All
Here’s something that surprises most people: a large number of rotator cuff tears are completely painless. A mass screening study of one village found that the prevalence of tears rose steadily with age, from about 11% in people in their 50s to nearly 37% in those in their 80s. Among people over 60 who had tears, roughly two-thirds had no symptoms whatsoever. Their shoulders functioned well enough that they never knew anything was wrong.
This doesn’t mean tears are harmless, but it does mean that a tear found on imaging isn’t automatically a crisis. The decision about whether to treat a tear, and how aggressively, depends on your symptoms, the size and location of the tear, how active you are, and whether the tear is getting worse over time.
How a Tear Is Diagnosed
Diagnosis usually starts with a physical exam. Your doctor will test your shoulder’s range of motion and strength in specific positions designed to isolate each rotator cuff muscle. Weakness or pain during these movements points toward a tear, but imaging confirms it.
Both MRI and ultrasound are highly accurate for detecting full-thickness tears. A large meta-analysis in the British Journal of Sports Medicine found that MRI, ultrasound, and MRI with contrast dye all performed similarly, with sensitivity between 90% and 91% and specificity between 93% and 95%. In practical terms, if you have a full-thickness tear, there’s about a 90% chance the scan will catch it, and a very low chance of a false alarm. Your doctor may choose one over the other based on availability and cost. Ultrasound has the advantage of being done in the office in real time, while MRI provides a more detailed picture of the surrounding structures.
Recovery Without Surgery
For partial tears and some full-thickness tears in less active individuals, physical therapy is often the first approach. The goal is to strengthen the remaining rotator cuff muscles and the surrounding shoulder blade muscles so they compensate for the damaged tendon. A study following 37 patients with partial tears treated conservatively found that 91% were still satisfied with their results roughly four years later. That’s a strong success rate, though it works best when the tear is small, the muscle quality is still good, and the patient commits to the exercise program.
Physical therapy for a rotator cuff tear typically focuses on restoring range of motion first, then gradually building strength. You can expect the process to take several months. Pain management during this time usually involves anti-inflammatory medications and sometimes a corticosteroid injection to calm the inflammation enough to participate in therapy.
What Surgical Repair and Recovery Look Like
Surgery is generally recommended for full-thickness tears in active people, tears that haven’t improved with several months of physical therapy, or tears caused by an acute injury. The most common procedure reattaches the torn tendon to the bone using small anchors, typically done arthroscopically through a few small incisions.
Recovery is slow because tendons heal to bone gradually. You’ll wear a sling for the first two to three weeks and start physical therapy about one week after surgery. For the first six to ten weeks, therapy focuses on gentle range-of-motion exercises to prevent stiffness while the repair heals. Strengthening exercises don’t begin until after that initial healing window. The full physical therapy program typically lasts three to four months, and most people continue improving for up to a year. Returning to heavy overhead work or sports usually takes six months or longer.
The timing of surgery matters. Because fatty infiltration and muscle atrophy begin early and worsen over time, delaying repair too long can reduce the quality of the remaining tissue. A tear that would have been straightforward to fix at three months may be much harder to repair at two years, especially if the muscle has significantly atrophied or filled with fat.