One of these works faster. The other tends to still be working later.

PLATELET-RICH PLASMA OR CORTICOSTEROID

This is the comparison that matters most, because a corticosteroid injection is what almost everyone is offered first, and because the two treatments do opposite things to tissue.

They are not two versions of the same idea

A corticosteroid injection suppresses. It powerfully inhibits the inflammatory cascade, reducing pain within days. PRP provokes. It delivers growth factors intended to restart a repair process, and the first thing you feel is more pain, not less.

Everything else follows from that difference. If you understand nothing else about the choice, understand that one treatment turns a signal down and the other turns it up, and that these are appropriate in different situations.

The crossover, and why it is so consistent

Across lateral epicondylitis, plantar fasciitis and knee osteoarthritis, comparative trials keep producing the same shape:

• Weeks 2–8. Corticosteroid clearly ahead. Faster, larger early relief.
• Around 3 months. The lines cross.
• 6–12 months. PRP ahead, and the gap widening.
• Beyond a year. In several tendon studies the steroid group has ended up worse than untreated controls.

That last point is the uncomfortable one. In chronic tendinopathy the tissue is not inflamed — it is degenerate and failing to repair. Suppressing what little repair signaling remains buys eight excellent weeks at the cost of the tendon’s own attempt to heal.

What repeated corticosteroid does over time

• Cartilage. Repeated intra-articular injection is associated with cartilage volume loss. In a joint you intend to keep for twenty more years this is a poor bargain.
• Tendon. Reduced tensile strength and an association with rupture. This is why steroid is avoided in and around the Achilles.
• Fat pad. Atrophy in the heel, which is permanent and leaves less natural cushioning than you started with.
• Skin. Depigmentation and subcutaneous atrophy at superficial sites.
• Blood glucose. A systemic rise for days to weeks, which matters considerably in diabetes and is often not mentioned.

When cortisone is the better choice

It genuinely often is, and a page that pretended otherwise would not be useful.

• A genuinely inflammatory condition — crystal arthropathy, inflammatory arthritis, a hot bursitis. Here suppression is the correct mechanism, not a compromise.
• When you need to be functional for a specific fixed event in the next month.
• As a diagnostic tool — a well-placed injection that abolishes pain tells you where the pain is coming from.
• Severe pain preventing any rehabilitation at all, where a window is needed before the work can start.
• When cost is decisive. Corticosteroid is covered by insurance and PRP is not, and pretending that is irrelevant would be dishonest.

When PRP is the better choice

• Chronic degenerative tendinopathy — where there is no inflammation to suppress and the problem is a stalled repair
• Someone who has already had one or two steroid injections that worked briefly and then did less
• A joint you want to protect over years rather than get through a season
• Diabetes, where the glycemic effect of steroid is a real cost
• Around the Achilles and other high-consequence tendons, where steroid risk is elevated

The one-two-three pattern to watch for

A recognizable sequence brings a lot of people here. The first steroid injection works beautifully for three months. The second works for six weeks. The third barely registers, and now the tendon is thinner on ultrasound than it was two years ago.

That is not bad luck and it is not the tendon getting worse on its own. Each injection suppressed the repair a little further while relieving the symptom, and the underlying degeneration continued unopposed. If you recognize that sequence in your own history, it is the strongest single argument for changing mechanism rather than repeating one.

Cost, honestly

Corticosteroid injection is covered. PRP is not, and it costs more per treatment. We do not publish prices on this website and we will not tell you what your insurer will do — a we do not bill insurance. Call and ask, and you will get a straight answer from someone who can see your case.

What we say about the economics: the relevant comparison is not one injection against another. It is a course of treatment plus rehabilitation against a repeating series of injections that each work for less time in a tissue that is quietly deteriorating.

Can you have both?

Sequentially, yes, and it is a reasonable plan in a specific situation: a tendon or joint too painful to load at all is a tendon that cannot do the rehabilitation PRP depends on. A steroid injection can open that window. What we avoid is mixing corticosteroid into the PRP preparation itself, because suppressing the inflammatory response is precisely what undermines the treatment.

Allow a reasonable interval — typically several weeks — between a steroid injection and PRP at the same site, so the suppression has worn off before the provocation arrives.

Why the same trial keeps producing arguments

If the crossover is so consistent, why does the debate continue? Three reasons worth knowing, because they explain why you will find confident claims in both directions.

Follow-up length decides the winner. A trial that stops at eight weeks reports that corticosteroid is superior. The same trial run to twelve months reports the opposite. Both are accurate descriptions of different questions, and headlines rarely say which was asked.

PRP is not a standardized product. Platelet concentration varies several-fold between systems, leukocyte content is frequently unreported, and activation methods differ. Pooling those trials into one estimate averages across interventions that are not really the same treatment, which flattens real effects toward the middle.

The control arm is not inert. A saline injection into a degenerate tendon still involves a needle passing through it repeatedly, and that fenestration is itself therapeutic. Trials comparing PRP against saline are often comparing two active treatments and reporting the difference as nothing.

None of this makes the comparison unknowable. It means the honest summary is directional rather than precise: for chronic degenerative tissue, provoking repair ages better than suppressing inflammation, and the size of that advantage depends on details most trials do not report.

Choosing between the two

Will cortisone ruin my joint?

One injection, no. Repeated intra-articular injections are associated with cartilage loss, which is a cumulative concern. Risks and side effects.

I have already had three steroid shots. Is PRP still worth it?

Often yes, and that history is itself an argument for changing mechanism. Candidacy.

Which works faster?

Cortisone, clearly, for the first two months. Then the picture reverses. Recovery timeline.

Can I have cortisone first and PRP later?

Yes, with an interval between them, and sometimes that is the right sequence. What to expect.

Related reading

• PRP compared with hyaluronic acid
• PRP for knee osteoarthritis
• Risks and side effects
• How PRP works

The two curves differ in shape, not just in height.