A partial rotator cuff tear in St. Louis can usually be treated without surgery, and surgery stays the exception for a tear that keeps growing. At our office we place platelet-rich plasma (PRP) right into the frayed tendon under ultrasound. Then we pair it with rehab and metabolic repair, so the tendon rebuilds instead of wearing thinner.
A partial-thickness tear is a rope with some of its strands cut. The rope still holds, so you can still lift your arm. But every overhead reach, and every night spent lying on that shoulder, pulls on the strands that are left. Leave it alone and the load shifts onto fewer fibers. Those fibers fail sooner, and a partial tear walks toward a full one.
The usual answer is a cortisone shot into the bursa. It quiets the pain for a few weeks. But it does nothing to rebuild the rope. And steroid slows the cells that make new collagen. You feel better while the tendon gets weaker. Most patients were never told they were making that trade.
The rotator cuff is four small tendons. They hold the ball of the shoulder in its socket while the big muscles move the arm. The supraspinatus, on top, takes the most abuse. A partial tear means the tendon is damaged on the joint side, the bursa side, or inside it, without a hole all the way through.
Typical signs:
Ultrasound in the exam room shows us the tear, how deep it is, and the state of the bursa. If the picture does not match the story, we order an MRI.
Partial tears are the common case, and they are the ones we treat. Conservative care matches surgery for partial-thickness cuff tears, which are about twice as common as full-thickness ones. Eubank and colleagues, reviewing 28 level-1 trials in 2024, put the numbers plainly: “Studies have shown partial-thickness rotator cuff tear (PTRCT) prevalence to be twice that of full-thickness tears.” A 2026 meta-analysis by Ricker and colleagues pooled 33 studies and 1,818 patients and found that what surgery added “remained below the minimal clinically important differences (MCID), indicating limited clinical relevance.” So we treat these tears with PRP placed into the tendon, graded loading and metabolic repair, and we work to avoid surgery on them.
Tendon has a poor blood supply. And the cuff has a stretch near where it attaches with the worst supply of all. Healing there runs on a thin trickle of nutrients. Three forces then decide whether that trickle wins:
The tear is where it hurts. The terrain is why it does not close.
We draw your blood and spin it in an FDA-cleared device to gather the platelets. Platelets are the repair workers. They release growth signals that call in new cells, start new collagen and build blood supply. Under ultrasound we place them into the torn part of the tendon, and into the bursa when it is involved. A tendon injection is only as good as its aim, and blind needles miss.
The evidence lines up with the biology. A 2026 pooled analysis of ten randomized trials covered 591 patients with cuff tendon damage or partial tears. It found cortisone and PRP equal in the first three months. By six months, PRP pulled ahead on pain and shoulder function, with fewer side effects. A randomized trial measured tears on MRI. PRP placed in the tear shrank it by about 3 mm over six months. Steroid in the bursa did not change tear size. The effect is real and modest. That is why the injection never travels alone.
For larger or older tears, bone marrow concentrate brings the general contractor. These cells organize the repair crew instead of only sending signals. More on the options is on our PRP injections page and the orthobiologics hub.
The procedure is done under local numbing. You are awake, there is no sedation, and most patients drive themselves home. Expect soreness for about 48 hours. That soreness is the repair workers starting the job. Protect the area for the first few days and follow the rehab plan.
The number of injections depends on need. Some people feel better in three weeks. Others need a second or third treatment, based on how the tissue responds. You can’t make a carrot grow faster than it grows. Collagen rebuilds on a calendar of months.
The injection is not the treatment. It is what makes the treatment possible. Lifestyle and behavior work is 40 to 50 percent of our protocol:
If your shoulder is also stiff, rule out the diabetic shoulder. It travels with the same metabolic terrain.
Dr. Padda is a licensed physician and surgeon, and surgery has a place. Some cases belong with a surgeon: a full tear from an injury in an active person, real weakness, or a tear that keeps growing on imaging. Orthobiologics are the bridge between failed conservative (non-surgical) care and the operating room. If we can rebuild the tendon, you keep it. If we can’t, you go to surgery with a healthier cuff than one softened by repeated steroid.
More on this condition from Dr. Padda on YouTube:
Strengthening the cuff itself is part of conservative care; see the band external rotation exercise for shoulder pain from our physiotherapy program.
Many can. Healing depends on how deep the tear is, the tendon’s quality, your metabolic health and how the shoulder is loaded. PRP, structured rehab and metabolic repair give the tendon its best odds.
Early on they work about the same. At six months, pooled trials favor PRP for pain and function, with fewer side effects. Steroid also slows collagen making in the tendon you are trying to save.
Soreness lasts about 48 hours. Many patients notice change within three to six weeks. The tendon keeps rebuilding for months.
No. We use local anesthetic, you stay awake, and most patients drive themselves home.
PRP is not billed to insurance. HSA and FSA funds are generally eligible.
Lying on the shoulder squeezes the cuff against bone. Blood flow to the tendon drops when the arm is still. The pain then breaks the sleep the tendon needs to repair.
A partial tear is a window. Use it while the tendon is still there to rebuild. Over 90% of our accepted case-study patients see significant improvement. That is a figure from our own patients, not a trial outcome, and individual results vary. Request the orthobiologics guide above, or call our office at 4477 Woodson Rd in St. Louis at (314) 481-5000. We will tell you plainly whether your shoulder is a candidate.
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