Supraspinatus Tendinosis and Tears

The tendon. The supraspinatus is one of the four rotator cuff tendons. It runs from the top of the shoulder blade, under the bony point of the shoulder (the acromion), to the top of the arm bone, and helps lift the arm and keep the ball of the joint centred in its socket. A thin sac, the subacromial-subdeltoid bursa, lies over it and lets it glide.

Tendinosis, tendinopathy, tendinitis. Reports use these words for much the same thing. On ultrasound the tendon looks thicker than usual, with darker, less orderly patches, and the report may say thickened, hypoechoic or heterogeneous. On MRI it shows brighter signal than a healthy tendon. In both, there is no gap running through it. The words describe the picture, not how much the shoulder hurts or how strong it is.

The words that come with it. These are the terms you are most likely to see beside it.

These findings are common in shoulders that do not hurt. In 51 men aged 40 to 70 with no symptoms in either shoulder, ultrasound showed a thickened bursa in 78 percent, wear in the AC joint in 65 percent, supraspinatus tendinosis in 39 percent and a bursal-sided partial tear of the supraspinatus in 22 percent. Ninety-six percent had at least one finding (Girish et al., 2011).

They become more common with age. Pooling 30 studies and 6,112 shoulders, rotator cuff abnormalities were found in 9.7 percent of people aged 20 and younger and in 62 percent of those aged 80 and older, and the rise with age was similar whether or not people had symptoms (Teunis et al., 2014). The authors concluded that cuff changes are a common part of normal aging, which makes it hard to tell from a scan whether a finding is new or is the cause of the pain.

Full-thickness tears are no exception. When 664 adults in one village had both shoulders scanned with ultrasound, 22.1 percent had a full-thickness tear: none in their 20s to 40s, 10.7 percent in their 50s and 36.6 percent in their 80s. About two in three of those tears caused no symptoms (Minagawa et al., 2013).

The size of a tear is not a pain score. In 393 people with a painful full-thickness tear that came on without an injury, no measure of how severe the tear was (its size, how far it had pulled back, or wasting of the muscle) was linked with how much it hurt (Dunn et al., 2014).

The report does not set the plan on its own. A 2022 Canadian guideline on rotator cuff disorders starts with the history and the examination, and says imaging is needed only in select circumstances (Lafrance et al., 2022). What changes the plan is usually the story: a sudden loss of strength after a fall or a heavy pull needs prompt medical assessment (see the warning signs above), and a shoulder that is stiff in every direction, even when someone else moves it, points to a frozen shoulder rather than the tendon.

• Gradually, over months. The story I see most often. Tendon changes build slowly with age, and pain tends to start when overhead work, lifting, a new sport or a busy spell increases faster than the shoulder is used to. Reaching up, reaching behind the back and lying on that side are the usual complaints. The rotator cuff page covers this pattern in detail.
• After a fall or a sudden pull. A sudden loss of strength after an injury can mean the tendon has torn through, whether or not it had changes before. This story does not start with exercise. It follows the warning signs on this page, and the conversation about a surgical opinion comes early, particularly for younger and active people.
• A calcium deposit. Calcium can collect inside the tendon and later break down and clear. In a trial that followed 48 people with calcific tendinitis for five years, the deposit had gone completely in most of them, whichever of the two treatments they had (de Witte et al., 2017).
• Something nearby. Because tendon changes are so common, a scan of a shoulder that hurts for another reason will often show them too. Pain from the neck, the AC joint or a stiffening joint can sit alongside them, and the examination sorts out which one is driving the pain.

The guideline and the trials agree on the first steps for tendinosis, a thickened bursa and partial tears. Full-thickness tears are where they differ.

• Exercise and education first. The 2022 guideline recommends an active, task-based rehabilitation program of exercise and education for adults with rotator cuff disorders. It does not recommend subacromial decompression for tendinopathy, and it sees surgery as appropriate for selected people with a full-thickness tear (Lafrance et al., 2022).
• Surgery to make more room. In the CSAW trial, 313 people with at least three months of pain and no full-thickness tear, who had already tried exercise and at least one steroid injection, were randomised to decompression, a placebo operation (an arthroscopy with nothing removed) or no treatment. Decompression did no better than the placebo operation, and both were only slightly better than no treatment, by too little to matter (Beard et al., 2018).
• Small tears that came on gradually. In 180 shoulders of people over 55 with a small supraspinatus tear and no injury behind it, physiotherapy alone, bone removal with physiotherapy, and tendon repair with both gave similar function, pain and satisfaction after about six years. Ten of the shoulders that were not repaired at first had a repair later (Kukkonen et al., 2021).
• Small to medium full-thickness tears. In 103 people with a full-thickness tear up to 3 cm, those whose tendon was repaired had better shoulder function, less pain and more pain-free movement at 15 years than those who started with physiotherapy, 15 of whom had a repair later. General health scores did not differ. In the tears treated with physiotherapy only, the average size had roughly doubled, from about 16 to 32 mm front to back (Moosmayer et al., 2024).
• Steroid injections. Across 11 trials in 726 people with rotator cuff tendinosis, a steroid injection eased pain a little more than a placebo injection at 4 to 8 weeks, but not at three months, and repeat injections did no better than one (Mohamadi et al., 2017). The guideline lists injections among the options that may ease pain in the short term (Lafrance et al., 2022).
• Calcium deposits. In a trial of 48 people with calcific tendinitis, needling the deposit under ultrasound to break it up and wash it out (barbotage), along with a steroid injection, gave better results at one year than the injection alone. At five years the two groups were similar, though fewer people in the needling group had needed further treatment (de Witte et al., 2017). These procedures are done by a doctor.
• What that means. For tendinosis, a thickened bursa, partial tears and small tears that came on gradually, exercise-based rehabilitation is the usual first step. A full-thickness tear is a more individual decision. After an injury with sudden weakness, or in a younger, active person, I refer early for a surgical opinion. For a small tear that came on gradually in someone over 55, starting with rehabilitation is a reasonable option, with a surgical opinion if the shoulder is not improving, because repair can offer an advantage for some tears over the long term.

I start with how the pain began and what it stops you doing. A gradual start alongside more overhead work, lifting or sport points one way; a sudden loss of strength after a fall or a heavy pull points another, and that story follows the warning signs on this page before anything else. I ask about sleep, work and sport, and what you need the shoulder to do again.

On examination I compare how far you can lift the arm with how far it moves when I lift it for you, because a shoulder that is stiff both ways points to a stiff joint, such as a frozen shoulder or arthritis, rather than the tendon. I test the strength of each part of the cuff, look for a painful arc as the arm lifts out to the side, check the AC joint and screen the neck, which can send pain to the same area. Then I read the report alongside what I have found. I cannot order imaging; when further imaging would change the plan, I flag it to your family doctor and refer you.

For tendinosis, a thickened bursa and partial or gradual tears, the plan is usually strengthening for the cuff and the shoulder blade muscles, starting with static holds if moving the arm hurts, with the overhead work that flares it trimmed for a time and then rebuilt. I also suggest sleep positions that take load off the shoulder. If pain is too high to load the shoulder at all, an injection through your doctor is an option to discuss. Progress is measured in strength and in what you can do, not by repeating the scan. If a full-thickness tear, or a large partial tear, stays weak or painful or is not improving after a fair course of rehabilitation, I refer you through your family doctor for a surgical opinion, and rehabilitation after a repair follows your surgeon’s protocol.