Frozen Shoulder vs. Rotator Cuff Tear: How to Tell Them Apart
Frozen Shoulder vs. Rotator Cuff Tear: How to Tell Them Apart
Quick summary
- Frozen shoulder (adhesive capsulitis) affects an estimated 2–5% of the general population, more often women, typically between ages 40 and 65 (Kelley et al., 2013).
- The single most useful clinical clue: in frozen shoulder, both active movement AND passive movement (someone else moving your arm for you) are restricted roughly equally, because the joint capsule itself has tightened — whereas rotator cuff problems typically show specific strength deficits with better-preserved passive motion.
- A simple clinical test — gentle pressure over the coracoid process at the front of the shoulder — was found to distinguish adhesive capsulitis from rotator cuff tears with about 96% sensitivity and 89% specificity (Carbone et al., 2009).
- Rotator cuff tears are surprisingly common even in people with zero shoulder symptoms — up to roughly 39% on ultrasound in some asymptomatic populations — so a tear showing up on a scan doesn't automatically explain someone's pain (Reilly et al., 2006).
"I can't lift my arm" can mean two very different things. Frozen shoulder and a rotator cuff tear can both leave someone struggling to raise an arm overhead, but the underlying problem, and the right way to manage it, are quite different. The good news is that a few specific clinical findings do a reasonably good job of separating the two.
Two Very Different Problems That Can Look Similar
Frozen shoulder, or adhesive capsulitis, is a condition where the capsule surrounding the shoulder joint becomes inflamed and progressively thickens and tightens, physically restricting how far the joint can move in every direction. It affects an estimated 2–5% of the general population, is more common in women, and most often develops between the ages of 40 and 65 (Kelley et al., 2013).
A rotator cuff tear, by contrast, is damage to one or more of the tendons that stabilise and move the shoulder joint. Depending on the tear's size and location, it can cause pain and weakness with specific movements, most often lifting the arm out to the side or overhead, without necessarily restricting the joint's overall capacity to move when someone else guides it.
The Single Most Useful Clinical Clue: Active vs. Passive Motion
Clinical guidelines highlight one distinction above most others: in frozen shoulder, both active range of motion (how far you can move your own arm) and passive range of motion (how far your arm moves when a clinician carefully guides it, with your muscles relaxed) are restricted to a similar degree, because the capsule itself has physically tightened. In a rotator cuff tear, shoulder strength is typically reduced in specific, predictable patterns tied to which tendon is affected, while passive motion is often much better preserved than active motion, since the joint itself usually isn't mechanically restricted (Kelley et al., 2013).
A Simple Test That Discriminates Well: The Coracoid Pain Test
One specific physical exam finding has been studied directly for this purpose: applying gentle digital pressure to the coracoid process (a bony prominence at the front of the shoulder) and comparing the pain response there to pain at the AC joint and the front-side of the subacromial area. In a study comparing people with adhesive capsulitis against those with rotator cuff tears, calcifying tendonitis, shoulder arthritis, AC joint arthropathy, and symptom-free controls, this "coracoid pain test" identified adhesive capsulitis with around 96% sensitivity and, when compared specifically against rotator cuff tears, about 89% specificity — meaning it was quite good at correctly ruling frozen shoulder in or out (Carbone et al., 2009).
Why a "Tear" on a Scan Doesn't Always Explain Your Pain
It's worth knowing that rotator cuff tears show up on imaging surprisingly often in people who have no shoulder symptoms at all. One study using ultrasound in symptom-free shoulders found a total tear prevalence (full- and partial-thickness combined) of close to 39%, and a separate MRI-based sample found around 26% (Reilly et al., 2006). This doesn't mean tears are unimportant, but it does mean a tear identified on a scan needs to be matched against the actual clinical picture — the specific pain pattern, strength testing, and motion findings — rather than assumed to be the full explanation on its own.
Practical Signs Worth Noting
- Can someone else move your arm further than you can move it yourself? If passive motion is clearly better than active motion, that leans toward a rotator cuff issue rather than frozen shoulder.
- Is movement restricted in every direction, including behind your back? A global, all-direction restriction is more typical of frozen shoulder.
- Is there specific weakness with certain movements rather than overall stiffness? Targeted weakness patterns point more toward the rotator cuff.
- How did it start? Frozen shoulder often develops gradually without a clear injury, while rotator cuff tears are sometimes, though not always, linked to a specific strain or injury.
- Don't assume a scan result is the full story — rotator cuff tears are common findings even in shoulders with no pain, so imaging needs to be interpreted alongside a proper physical assessment.
Struggling to lift or move your shoulder and not sure why?
A hands-on assessment comparing your active and passive movement, strength, and specific pain responses can help clarify what's actually driving your symptoms.
Frequently Asked Questions
How can I tell if I have frozen shoulder or a rotator cuff tear?
The key clinical clue is whether someone else can move your arm further than you can move it yourself. In frozen shoulder, both active and passive movement are restricted to a similar degree because the joint capsule itself has tightened. In a rotator cuff tear, passive motion is often noticeably better than active motion, with specific strength deficits instead.
How common is frozen shoulder?
Frozen shoulder (adhesive capsulitis) is estimated to affect 2-5% of the general population, more commonly women, typically developing between ages 40 and 65.
Does a rotator cuff tear on a scan mean that's definitely causing my pain?
Not necessarily. Research has found rotator cuff tears on imaging in a large proportion of shoulders with no symptoms at all, up to around 39% on ultrasound in one study. A scan finding needs to be matched against your actual symptoms and physical exam findings rather than assumed to be the automatic explanation for pain.
Is there a specific physical test that distinguishes frozen shoulder from a rotator cuff tear?
Yes. A study found that pressing on the coracoid process at the front of the shoulder and comparing the pain response to other areas correctly identified adhesive capsulitis with around 96% sensitivity and about 89% specificity against rotator cuff tears.
References
- Kelley, M.J., Shaffer, M.A., Kuhn, J.E., et al. (2013). Shoulder pain and mobility deficits: Adhesive capsulitis. Journal of Orthopaedic & Sports Physical Therapy, 43(5), A1–A31.
- Carbone, S., Gumina, S., Vestri, A.R., & Postacchini, R. (2009). Coracoid pain test: A new clinical sign of shoulder adhesive capsulitis. International Orthopaedics, 34(3), 385–388. https://doi.org/10.1007/s00264-009-0791-4
- Reilly, P., Macleod, I., Macfarlane, R., Windley, J., & Emery, R.J.H. (2006). Dead men and radiologists don't lie: A review of cadaveric and radiological studies of rotator cuff tear prevalence. Annals of The Royal College of Surgeons of England, 88(2), 116–121. https://doi.org/10.1308/003588406X94968
