Your knee usually gets sore for a clear reason

Arthritis often causes stiffness after rest

Knee osteoarthritis is the common kind of arthritis. It slowly thins the cartilage covering your knee bones. Your knee may feel stiff when you stand.

It'll loosen after several steps.

Extra activity can raise soreness later. Poor sleep may make the ache feel stronger. That doesn't always mean the knee has new damage.

Catching or sharp pain needs an exam

A meniscus is a firm pad inside your knee. It spreads pressure between the bones. A worn or torn pad may catch during turns.

Touch alone can't tell you the cause.

An exam checks motion, swelling, strength, and balance. A locked knee isn't a normal flare. Fast swelling after an injury also needs prompt care.

Newer treatments don't help every knee

Research doesn't agree on whether blood-based care helps you walk or climb stairs more easily. One strong test found it worked no better than salt water. Your knee still needs its own review.

Nerve care uses heat or cold on small nerves.

It aims to stop soreness signals, not repair the joint. The studies reported no serious harm, but results varied. QC Kinetix's Chandler team offers platelet-rich plasma (PRP), a regenerative treatment made by drawing and spinning your blood before placing the prepared part in your knee.

Sources

1. In the 68-week STEP 9 trial, 407 participants with obesity (mean BMI 40.3) and moderate knee OA with at least moderate pain were randomized 2:1 to once-weekly semaglutide 2.4 mg or placebo alongside diet and activity counselling. Weight change was -13.7% vs -3.2%, and WOMAC pain improved -41.7 vs -27.5 points (both P<0.001). Gastrointestinal adverse events drove discontinuation in 6.7% vs 3.0%.

   Bliddal H, Bays H, Czernichow S, et al. — Once-Weekly Semaglutide in Persons with Obesity and Knee Osteoarthritis.. New England Journal of Medicine, 2024. DOI: 10.1056/NEJMoa2403664.

2. A 2026 systematic review and meta-analysis of eight sham-controlled RCTs (n=627) found genicular nerve ablation (radiofrequency or cryoneurolysis) reduced knee OA pain versus sham at 12 weeks (MD -1.65; 95% CI -2.57 to -0.74) and improved WOMAC function (MD -11.37), with high heterogeneity (I2 83-91%) and no serious adverse events reported. The population studied was patients INELIGIBLE for arthroplasty.

   Pain Medicine authors — Efficacy and safety of genicular nerve ablation techniques for knee osteoarthritis: a systematic review and meta-analysis of sham-controlled randomized trials.. Pain Medicine, 2026. DOI: 10.1093/pm/pnaf140.

3. A 2026 Cochrane review searching from 2010 to January 2025 found only ONE randomised trial (100 participants, Denmark) comparing knee arthroplasty with non-surgical treatment. Low-certainty evidence indicated TKA may reduce pain at one year by a clinically important margin (MD 17.60, 95% CI 8.25 to 26.95) and may improve function by an amount that might not be clinically important (MD 12.40), with probably no clinically important difference in health-related quality of life.

   Cochrane Musculoskeletal Group — Total and partial knee arthroplasty versus non-surgical interventions of the knee for moderate to severe osteoarthritis.. Cochrane Database of Systematic Reviews, 2026. DOI: 10.1002/14651858.CD015378.pub2.

4. A systematic review and meta-analysis of 32 trials classified PRP by total deliverable platelets and found all dose bands beat hyaluronic acid, with the moderate-dose band (5-10 billion platelets) showing the largest effect (SMD 1.48) and the low (1-5 billion) and high (>10 billion) bands moderate effects (SMD 0.47 and 0.68) — evidence that dose, not brand, drives reported differences.

   PM&R authors — Platelet-rich plasma outcomes in knee osteoarthritis are associated with the amount of total deliverable platelets: A systematic review and meta-analysis.. PM&R, 2026. DOI: 10.1002/pmrj.13455.

5. A 2026 network meta-analysis of 21 RCTs (2,254 patients) found both leukocyte-poor and leukocyte-rich PRP significantly improved 6-12 month WOMAC function versus placebo (MD -10.54 and -13.20 respectively) and both were superior to hyaluronic acid, with leukocyte-poor PRP ranked first (P-score 0.96) — a materially more favourable read of PRP than the RESTORE trial, which is why this corpus presents both.

   Journal of Orthopaedic Surgery and Research authors — Leukocyte-rich versus leukocyte-poor platelet-rich plasma and hyaluronic acid for knee osteoarthritis: a systematic review and network meta-analysis.. Journal of Orthopaedic Surgery and Research, 2026. DOI: 10.1186/s13018-026-06689-4.

6. A meta-analysis of 28 RCTs (3,246 knee OA patients) reported PRP gave pain relief comparable to hyaluronic acid with better functional improvement, no significant difference versus corticosteroid as monotherapy, and better pain and function than physical or exercise therapy; the authors also reported better outcomes in KL grade I-II knees, i.e. earlier disease.

   European Journal of Medical Research authors — Efficacy and safety of platelet-rich plasma injections for the treatment of knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials.. European Journal of Medical Research, 2025. DOI: 10.1186/s40001-025-03253-4.

7. A prospective longitudinal study of 64 patients with acute medial meniscus posterior root tear managed non-operatively found 76.6% continued non-operative care and only 23.4% converted to surgery (median 6 months). Pain fell from 7.6 to 1.3 on an 11-point scale within 6 months and stayed there — even though structural degeneration on MRI progressed. Symptoms and structure moved in opposite directions.

   Knee Surgery, Sports Traumatology, Arthroscopy authors — Clinical improvement despite structural degeneration after nonoperative treatment of medial meniscus posterior root tear: A prospective longitudinal study.. Knee Surgery, Sports Traumatology, Arthroscopy, 2026. DOI: 10.1002/ksa.70570.

8. A phase II multicentre RCT randomized 60 knee OA patients to three weekly PRGF injections or 100 million cultured autologous bone marrow mesenchymal stromal cells plus PRGF. No adverse effects were reported. VAS pain improved significantly in the BM-MSC+PRGF arm (5.3 to 3.5, p=0.01) but not in the PRGF-alone arm (5.0 to 4.5, p=0.389) at 12 months — a positive signal at small scale, in an unblinded active-control design.

   Lamo-Espinosa JM, et al. — Phase II multicenter randomized controlled clinical trial on the efficacy of intra-articular injection of autologous bone marrow mesenchymal stem cells with platelet rich plasma for the treatment of knee osteoarthritis.. Journal of Translational Medicine, 2020. DOI: 10.1186/s12967-020-02530-6.

9. The RESTORE trial randomized 288 adults aged 50+ with symptomatic mild-to-moderate medial knee OA to three weekly leukocyte-poor PRP injections or saline placebo. At 12 months, pain change was -2.1 vs -1.8 points (difference -0.4; 95% CI -0.9 to 0.2; P=.17) and medial tibial cartilage volume change was -1.4% vs -1.2% (P=.81). 29 of 31 prespecified secondary outcomes showed no significant between-group difference. The authors concluded the findings 'do not support use of PRP for the management of knee OA.'

   Bennell KL, Paterson KL, Metcalf BR, et al. — Effect of Intra-articular Platelet-Rich Plasma vs Placebo Injection on Pain and Medial Tibial Cartilage Volume in Patients With Knee Osteoarthritis: The RESTORE Randomized Clinical Trial.. JAMA, 2021. DOI: 10.1001/jama.2021.19415.

10. FDA states verbatim: 'None of these products have been approved for the treatment of any orthopedic condition, such as osteoarthritis, tendonitis, disc disease, tennis elbow, back pain, hip pain, knee pain, neck pain, or shoulder pain.' The only FDA-approved stem cell products in the United States are blood-forming (hematopoietic progenitor) cells derived from umbilical cord blood, approved only for disorders of blood production. There are currently NO FDA-approved exosome products.

    U.S. Food and Drug Administration — Consumer Alert on Regenerative Medicine Products Including Stem Cells and Exosomes. FDA (Center for Biologics Evaluation and Research), 2020.