Rotator Cuff Tear After a Car Accident: Why Your Shoulder Still Hurts

A rotator cuff tear after a car accident happens when the shoulder is loaded hard against the belt, the door or the wheel. Many of these tears are partial. Most should start with an exam, an ultrasound and guided rehab, not surgery. Platelet-rich plasma (PRP) is one option when a partial tear stops healing.

Here is the part nobody tells you. The tear is often not what keeps you from lifting your arm six months later. The stiff, guarded shoulder you built to protect it is. Pain makes you stop moving. Stillness makes the joint capsule tighten. A tight capsule makes every reach hurt more. So you move even less. That loop, not the tear alone, is what we break first.

How does a car crash tear the rotator cuff?

The rotator cuff is four small tendons. They hold the ball of the shoulder in its socket. They were built to steer the arm, not to stop a body moving at 30 miles an hour.

In a crash, a few things load them past their limit in a fraction of a second:

• Bracing. You grip the wheel and lock your arms just before impact. The force runs up your arms into both shoulders.
• The seat belt. It does its job by stopping your chest. The shoulder under the strap takes a sudden, hard load.
• The door. In a side impact, the arm or shoulder hits the door frame.
• The reach. Turning to catch a phone, a bag or a child in the back seat puts the tendon in its weakest position.

Pain is not always loud on day one. Adrenaline and a sore neck can hide it. Many people notice the shoulder days later, when they try to put on a coat or sleep on that side. Night pain and weakness when lifting the arm out to the side are the classic clues.

Was the tear already there before the crash?

This is the first question an insurer asks, so it is worth knowing the answer. Tendon wear is common with age. A pooled study of more than 6,000 shoulders found cuff changes in about 10% of people age 20 and under and in 62% of people 80 and over, with or without pain. So an MRI finding by itself cannot date a tear.

What helps tell old wear from new injury is the story around the scan. Did you lift, sleep and work without trouble before the crash? Did pain start soon after? Does the exam match the image? Does the MRI show fresh swelling around the tendon? A shoulder that worked fine for years and then failed after a crash is a change in function, and function is what matters. Our page on proving an aggravated pre-existing condition walks through how that is written up.

What treatment comes first for a torn rotator cuff?

Standard injury care comes first, and it works for many people. The plan usually looks like this:

• A hands-on exam and an ultrasound in the office, so we can see the tendon move.
• A sling for days, not weeks. Longer than that and the shoulder starts to freeze.
• Rehab that trains the shoulder blade and the cuff together, not just the sore spot.
• Short courses of anti-inflammatory medicine if your stomach and kidneys allow it.

A cortisone shot can calm a bad flare so you can sleep. Repeated cortisone into a torn tendon is a trade we rarely make, because it calms pain without helping the tendon heal.

Long-term studies of rotator cuff tears show that rehab-first care does about as well as surgery for partial tears. Full-thickness tears in younger, active people are different. Surgery tends to do better there, and waiting too long can let the torn tendon pull back. If your tear needs a surgeon, we say so early and send you to one.

Where does PRP fit for a rotator cuff tear?

PRP is made from your own blood. We draw it, spin it and concentrate the platelets. The platelets carry growth signals that tell a slow-healing tendon to restart repair. It is one tool, used when a partial tear has stalled despite good rehab.

In a review of 11 controlled trials, PRP for partial tears did better than placebo for pain and shoulder function at every follow-up point. It also beat other non-surgical care at two to three months and again after six months. That is the window where you want a tendon to hold.

How it is done matters as much as what is injected. We place PRP under ultrasound, so it goes into the torn part of the tendon and not the space next to it. Results depend on the platelet dose that actually gets delivered, and on the rehab around it. For a larger partial tear, bone marrow concentrate is sometimes discussed instead. The number of injections follows how the tendon responds, not a preset package.

The visit itself is simple. We use local anesthetic. You stay awake, and most people drive themselves home. Expect a sore shoulder for about 48 hours.

PRP also has a role when surgery is needed. In a 2026 review of repairs, leukocyte-poor PRP added at surgery lowered the chance of the repair tearing again. That choice belongs to the surgeon who does the repair.

How does a shoulder tear affect your injury claim?

A shoulder hurt in a crash is often missed, because the neck gets the attention. If the shoulder is not in the early records, someone will later argue it came from something else. Tell every provider about the shoulder from the first visit.

PRP is usually not covered by health plans. That is a coverage decision, not a verdict on whether it works, as we explain in not covered is not the same as not proven. HSA and FSA funds can generally be used for it. If PRP becomes part of your plan, the record has to show why, and our page on documenting orthobiologic care for a claim lists what that record needs.

What should you do this week?

Do not wait for the shoulder to “settle down” in a sling. Keep it moving within what it allows. Write down what you could do before the crash and what you cannot do now. Get an exam that includes an ultrasound. And look at what your body is healing with. A tendon repairs itself from the same blood sugar and inflammation level as the rest of you, which is why we check the metabolic terrain before an orthobiologic. The shoulder you protect too long becomes the shoulder you lose.

Related reading: whiplash injury care, what the orthobiologic guidelines say after an injury and why ultrasound guidance matters for an injection.

All orthobiologic care: Our orthobiologics and PRP injections page lists every injury we treat with PRP, bone marrow concentrate and microfragmented fat.

Frequently asked questions

Can a rotator cuff tear heal without surgery?

Many partial tears improve without surgery when rehab, time and, in some cases, PRP are used well. A full-thickness tear in a young, active person is more likely to need a surgeon, and we refer early when that is the case.

How long after a car accident can shoulder pain start?

It can start right away or show up over the next few days, once the adrenaline wears off and you try normal tasks again. Report it as soon as you notice it so it is in your record.

Do I need an MRI for a rotator cuff tear?

Not always at first. An office ultrasound can show many cuff tears and lets us watch the tendon move. An MRI helps when a full-thickness tear is suspected or when surgery is being weighed.

Is a PRP injection in the shoulder painful?

We numb the skin and the path with local anesthetic, and you stay awake. Most people feel pressure during the injection and soreness for about two days after.

Will my health insurance pay for PRP?

Most health plans do not cover PRP. HSA and FSA funds can generally be used. In an injury claim, the charge is often handled through the claim; we explain the options before scheduling.

Where is Injury Experts located?

Accident and Injury Experts is at 4477 Woodson Rd, Suite 202, St. Louis, MO 63134, next to Lambert International Airport, with parking at the door. Call (314) 887-5866. Directions and hours are on our contact page.

Medically reviewed by Dr. Gurpreet Singh Padda, MD, MBA, MHP. Board Certified in Anesthesiology, Pain Medicine, Interventional Pain Management, Addiction Medicine, and Obesity Medicine. Last reviewed October 3, 2026.