A shoulder that hurts is usually one of a small number of problems. Working out which one is what decides everything else — whether it settles on its own, whether an injection is worth doing, and whether an operation is ever on the table.
Most of what follows can be sorted out in a single visit, because the examination and the ultrasound happen in the same room, on the same day, with the surgeon who would do the treatment.
Rotator cuff or labrum? The difference that confuses everyone
This is the single most common question people arrive with, usually holding an MRI report that mentions both. They are two different structures doing two different jobs, and the distinction changes the treatment completely.
- The rotator cuff is muscle and tendon. Four muscles wrap the top of the upper arm bone, and their tendons attach onto it. Their job is to move the arm and to hold the ball centred in the socket while the bigger muscles do the heavy lifting. The cuff sits on the outside of the joint.
- The labrum is cartilage. It is a rim of fibrous cartilage around the edge of the socket itself, deepening what is otherwise a very shallow dish. Its job is stability — it is a bumper, not a mover. The labrum sits inside the joint.
So no, the labrum is not part of the rotator cuff. They are neighbours that get injured in different ways, by different people, at different ages.
How the two injuries actually differ
| Rotator cuff tear | Labral tear | |
|---|---|---|
| What it is | Tendon pulled partly or fully off the bone | Cartilage rim torn off the edge of the socket |
| Typical patient | Over 40, often no single injury — it wears | Younger, usually a specific event: a dislocation, a fall, or years of throwing |
| Main symptom | Pain reaching overhead, pain at night, weakness lifting | Catching, clicking, a shoulder that feels unstable or untrustworthy |
| Where it hurts | Outer upper arm, often halfway down | Deep in the joint, hard to point at |
| Best imaging | Ultrasound (moving, under load) or MRI | MRI, usually with contrast inside the joint |
| Can biologics help? | Yes for tendinopathy and partial tears — a real evidence base | No injection reattaches a detached labrum |
The complication is that plenty of shoulders have both, and one of them is causing the symptoms while the other is an incidental finding. A degenerative labral fray in a sixty-year-old shoulder with a painful cuff is almost never the problem. A labral tear in a twenty-two-year-old who dislocated playing football almost always is.
Sorting out which finding is driving your symptoms is the entire job of the first visit, and it is done by matching the history and the examination to the imaging — not by reading the report on its own.
Where to go next: rotator cuff tears · labral tears from instability and dislocation · SLAP tears at the biceps anchor.
Start with what is actually wrong
Find the description that sounds most like your shoulder.
- Rotator cuff pain, impingement and bursitis — it hurts reaching overhead and at night, there was no injury, and nobody has given you a firm diagnosis. Start here. It also explains why impingement, bursitis and tendinitis are largely one problem with several names.
- Rotator cuff tears — partial and full-thickness — a scan has found a tear and you want to know whether it needs repairing. Includes eight-year outcome data from this practice on treating partial-thickness tears without surgery.
- Shoulder instability, dislocation and labral tears — the shoulder has come out, or feels as though it might. Covers dislocation, Bankart tears and ligament injury, which are one problem under several names.
- SLAP tears and the Buford complex — a labral tear at the top of the socket, where the biceps anchors. Also covers the normal anatomic variant that is regularly mistaken for one on a scan.
- Rotator cuff re-tear — you have had a repair and the shoulder has gone backwards.
- Internal impingement — pain at the back of the shoulder in throwers and overhead athletes, at the extreme of the cocking position.
If none of those fit, that is useful information rather than a dead end. Shoulder pain is also referred from the neck, from the AC joint on the top of the shoulder, and from a frozen shoulder — and all three get mislabelled as rotator cuff problems for months at a time. Sorting that out is what the first visit is for.
What an assessment here actually involves
History and examination first, because they narrow the field faster than any scan. Then diagnostic ultrasound in the same visit, performed by the physician rather than booked out to a separate appointment somewhere else.
Ultrasound suits the shoulder unusually well. It shows the rotator cuff and bursa moving — in real time, under load, in the position that actually produces the pain — which a static scan of a shoulder lying still cannot do. It allows the sore shoulder to be compared directly against the other one. And when an injection is indicated, it turns that injection from a landmark-guided procedure into a directly visualised one.
The honest limit: ultrasound does not assess the labrum. That structure sits too deep inside the joint. Where a labral tear is the question, the study is an MRI, usually with contrast placed inside the joint. Both have their place and they answer different questions.
Where PRP and orthobiologics genuinely help
This field has a marketing problem, so it is worth being specific about which shoulders these treatments suit.
- Rotator cuff tendinopathy and partial-thickness tears — where the tendon is degenerative or partly torn but still attached. This is the best-supported indication in the shoulder, and it is what the eight-year data from this practice is drawn from.
- The irritable structures around a bigger problem — an inflamed biceps tendon, a thickened bursa, an AC joint that has become the pain generator.
- Augmenting a surgical repair — an active area of research rather than a settled one, and it should be described that way.
And where they do not. No injection reattaches a labrum that has come off the rim of the socket, and none closes a full-thickness tear across a gap. Those are mechanical problems. Any clinic implying otherwise is describing a result the published literature does not support.
The detail is on the PRP and orthobiologics for the shoulder page, including what the injections involve and what they cost.
When surgery is the right answer — and when it is not
Some shoulders need an operation. A large traumatic cuff tear in an active patient, a recurrent dislocator with bone loss, a shoulder that has failed a proper rehabilitation programme — those are real indications and the results are good.
Plenty of others do not. The clearest example is the operation most often offered for impingement: when arthroscopic subacromial decompression was tested against a placebo operation in randomised trials, it did not outperform the placebo. That result is worth knowing before anyone books you a date.
Don Buford, M.D. is a board-certified orthopedic surgeon with more than 26 years in practice and over 2,000 rotator cuff repairs performed, and he also performs the ultrasound and the injections personally. That combination is the point: a practice that only injects has one answer available, a practice that only operates has a different one, and someone who does both has no structural reason to steer you either way.
Common questions
Is the labrum part of the rotator cuff?
No. They are two different structures. The rotator cuff is four muscles and their tendons, sitting on the outside of the joint, and its job is to move the arm and hold the ball centred. The labrum is a rim of fibrous cartilage around the edge of the socket itself, inside the joint, and its job is stability rather than movement. They are neighbours that get injured in different ways, by different people, at different ages — and plenty of shoulders have findings in both, with only one of them causing the symptoms.
How do I know which shoulder problem I have?
Most shoulder pain sorts into a small number of patterns. Pain reaching overhead and at night with no injury usually points at the rotator cuff and the bursa. A shoulder that has come out, or feels as though it might, points at instability. Deep pain at the front with catching in overhead athletes points at the biceps anchor. What settles it is examination plus ultrasound in the same visit, because several of these look identical on paper and behave very differently under load.
Do I need an MRI before my first visit?
Usually not. An MRI on a painful shoulder frequently finds changes that are also present in shoulders that do not hurt, and an incidental finding can push treatment in the wrong direction. Examination plus ultrasound answers most questions on the day. An MRI earns its place when surgery is genuinely being considered, when there has been real trauma, or when a labral tear is the question — because ultrasound cannot assess the labrum.
Can PRP or stem cell injections fix my shoulder?
It depends entirely on what is wrong. For rotator cuff tendinopathy and partial-thickness tears, orthobiologics have a genuine evidence base, and this practice has published eight-year outcome data on exactly that. For a labrum detached from the rim of the socket or a full-thickness tear across a gap, no injection reattaches tissue, and any clinic implying otherwise is describing a result the literature does not support. Getting the diagnosis right is what makes the difference.
Is my shoulder pain actually coming from my shoulder?
Not always, and this is missed regularly. Pain is referred into the shoulder from the neck, and pain on the top of the shoulder usually comes from the AC joint rather than the rotator cuff. A frozen shoulder gets mislabelled as impingement for months at a time — the giveaway is loss of passive external rotation, which someone has to test for deliberately. Ruling these in or out changes the treatment more often than people expect.
Will I be told I need surgery?
Only if you do. Some shoulders need an operation and the results are good — a large traumatic cuff tear in an active patient, a recurrent dislocator with bone loss, a shoulder that has failed proper rehabilitation. Plenty of others do not. The operation most often offered for impingement did not outperform a placebo operation when it was tested in randomised trials, and that is worth knowing before anyone books you a date.
Who performs the ultrasound and the injection?
Don Buford, M.D., a board-certified orthopedic surgeon, performs both personally, in the same visit as the examination. Because the same physician offers the injection and the operation, the recommendation is not limited to whatever happens to be on the menu.
