What to check before PRP and when not to wait

What to try and what to bring

Try steady exercise, lighter activity, a brace, or safe medicine first. If extra weight strains a knee or hip, losing some can ease its work. Exercise won't show much after only a few days. It needs to build strength without leaving a lasting flare. Your doctor or therapist can change it when the soreness rises.

Write down which care helped and which didn't. Take old reports and a complete medicine list. Include therapy, braces, and past joint shots. Name the sore movement and the ache's usual length. For stairs, say whether going up or down feels worse.

Tell the doctor if you take blood thinners or bruise easily. Don't stop those medicines by yourself. An infection or a blood problem can make a planned shot unsafe.

When to seek care without waiting

Get prompt care for a hot, badly swollen joint. Fever or feeling ill makes it more urgent. A hard fall, a new bend, or trouble standing also needs quick care. These signs can mean infection or a broken bone.

New weakness or numbness with back soreness needs fast help. Get urgent help if you lose bladder or bowel control. If a pop leaves an arm or leg useless, don't wait. Calf swelling after being still can mean a blood clot.

These problems need an exam now. They aren't reasons for a visit scheduled days later.

Sources

1. The ESSKA-ICRS consensus applied the RAND/UCLA appropriateness method to 216 clinical scenarios for intra-articular PRP in knee OA. Only 84 scenarios (38.9%) were rated appropriate, 9 (4.2%) inappropriate and 123 (56.9%) uncertain. PRP was judged appropriate in patients aged 80 or under with KL grade 0-III osteoarthritis AFTER failed conservative non-injective or injective treatment; it was NOT considered appropriate as a first treatment, nor in KL grade IV (bone-on-bone) osteoarthritis, where 91.7% and 87.5% of scenarios respectively were uncertain.

   Kon E, de Girolamo L, Laver L, et al. — Platelet-rich plasma injections for the management of knee osteoarthritis: The ESSKA-ICRS consensus. Recommendations using the RAND/UCLA appropriateness method for different clinical scenarios. Knee Surgery, Sports Traumatology, Arthroscopy, 2024. DOI: 10.1002/ksa.12320.

2. The American Academy of Physical Medicine and Rehabilitation convened a technical expert panel that ran a structured literature review (2023, updated through June 2025) and a modified Delphi process, and issued five evidence-based clinical recommendations plus 11 consensus-based best practices for PRP in knee osteoarthritis. The statement is explicit that orthobiologic therapies 'remain an evolving area of practice' and that robust, dose-dependent randomized controlled trials are still needed to establish PRP's clinical effects.

   Borg-Stein J, Jayaram P, Colorado BS, et al. — AAPM&R guidance statement on platelet rich plasma for knee osteoarthritis. PM&R, 2026. DOI: 10.1002/pmrj.70144.

3. A study training predictive models on imaging features found that neither radiographic grading (IRF) nor MRI-based MOAKS scoring predicted patient pain or symptoms in knee osteoarthritis - the best model reached an R-squared of only 0.28, and predictive performance got WORSE as symptoms got more severe. An X-ray grade is not a prediction of how much someone hurts, and it is not on its own a reason to treat or not treat.

   Hill BG, Eble S, Moschetti WE, et al. — The Discordance Between Pain and Imaging in Knee Osteoarthritis. Journal of the American Academy of Orthopaedic Surgeons, 2025. DOI: 10.5435/JAAOS-D-24-00509.

4. A systematic review of patient dissatisfaction after total knee arthroplasty found dissatisfaction turned mainly on pre-operative expectations, the degree of improvement in knee function, and pain relief after surgery, with fewer associations in socioeconomic or surgical domains. Joint replacement is a very good operation that does not satisfy everyone, which is why the timing conversation is a real conversation and not a formality.

   Gunaratne R, Pratt DN, Banda J, et al. — Patient Dissatisfaction Following Total Knee Arthroplasty: A Systematic Review of the Literature. The Journal of Arthroplasty, 2017. DOI: 10.1016/j.arth.2017.07.021.

5. The 2019 ACR/Arthritis Foundation osteoarthritis guideline makes STRONG recommendations for exercise, weight loss in people with overweight or obesity, self-management programmes, tai chi, cane use, tibiofemoral bracing, topical and oral NSAIDs and intra-articular glucocorticoid injections for knee OA. Its conditional recommendations cover balance exercises, yoga, CBT, acupuncture, thermal modalities, radiofrequency ablation, acetaminophen, duloxetine and tramadol. Anything offered before a course of the strongly recommended options is being offered out of order.

   Kolasinski SL, Neogi T, Hochberg MC, et al. — 2019 American College of Rheumatology/Arthritis Foundation Guideline for the Management of Osteoarthritis of the Hand, Hip, and Knee. Arthritis & Rheumatology, 2020. DOI: 10.1002/art.41142.

6. PATH-2 randomised 230 adults with acute Achilles tendon rupture managed non-surgically to PRP or a placebo dry-needle injection across 19 UK hospitals, with a central laboratory confirming the PRP was of good quality with the expected growth-factor content. At 24 weeks there was no detectable difference in muscle-tendon function (limb symmetry index 34.7% versus 38.5%; adjusted mean difference -3.9%; 95% CI -10.5% to 2.7%) or in any secondary outcome or adverse-event rate.

   Keene DJ, Alsousou J, Harrison P, et al. — Platelet rich plasma injection for acute Achilles tendon rupture: PATH-2 randomised, placebo controlled, superiority trial. BMJ, 2019. DOI: 10.1136/bmj.l6132.