What can soreness tell you about the joint?

Why does the ache change from day to day?

The work placed on a joint changes through the day. A long walk asks more from a knee or hip. Overhead reaching loads the shoulder and its tendons, so soreness may rise after harder work.

A short rest can settle soreness, but too much rest may add stiffness. Gentle motion can help the joint loosen again. Warmth may help before movement, while cooling may soothe it later. Don't keep using either if the soreness increases.

Why doesn't the X-ray match the soreness?

An X-ray shows bones and spaces within the joint, including wear caused by arthritis. It can't measure how much the joint hurts today. Muscles, tendons, swelling, and old injuries also affect movement.

The clinician therefore uses the X-ray along with an exam. Your answers show which tasks hurt and how long soreness lasts. The exam finds lost motion, weakness, or a tender area. Both kinds of information help explain your trouble.

How does the cause change your care choices?

Care depends on which joint hurts and what caused the soreness. A tender tendon isn't the same as wear inside a knee. Early wear also differs from severe joint damage. The exam must identify the problem before you compare care.

Blood-based care may aim to keep your own joint working. QC Kinetix offers orthobiologics, clinic procedures in which medical providers prepare your blood and use it at the sore joint. That purpose is called joint preservation. Some studies found relief, while other careful studies found no added help.

Sources

1. The ESSKA-ORBIT European consensus on blood-derived orthobiologics graded 28 question-statement sets; only 9 of 28 had high-level scientific support. Three statements reached grade A: that there is enough preclinical and clinical evidence to support PRP use in knee OA; that clinical evidence shows effectiveness in MILD TO MODERATE knee OA (KL grade 3 or lower); and that PRP provides a longer effect than the short-term effect of corticosteroid with a safer profile. The panel regarded PRP as a valid and possible first-line injectable option for KL grades 1-3.

   Laver L, et al. — The use of injectable orthobiologics for knee osteoarthritis: A European ESSKA-ORBIT consensus. Part 1-Blood-derived products (platelet-rich plasma).. Knee Surgery, Sports Traumatology, Arthroscopy, 2024. DOI: 10.1002/ksa.12077.

2. The companion ESSKA-ORBIT consensus on cell-based therapy (77 experts, 22 countries, 27 statements) found only 5 of 27 statements reached recommendation level A or B; 22 were rated C or D. It concluded that cell-based therapy shows clinical benefit in pain and function up to 12 months for KL grades 1-3 with some benefit in selected KL 4, but that because of limited high-quality studies and NO clear superiority over other injectables it should be considered a SECOND-LINE option, after other non-operative treatment fails.

   de Girolamo L, et al. — The use of injectable orthobiologics for knee osteoarthritis: A formal ESSKA-ORBIT consensus. Part 2-Cell-based therapy.. Knee Surgery, Sports Traumatology, Arthroscopy, 2025. DOI: 10.1002/ksa.70001.

3. A phase III double-blind placebo-controlled trial of a SINGLE injection of culture-expanded autologous adipose-derived MSCs in 261 patients with KL grade 3 knee OA found significantly better VAS pain (25.2 vs 15.5 mm improvement; P=.004) and total WOMAC (21.7 vs 14.3; P=.002) at 6 months versus placebo, with no serious treatment-related adverse events - but MRI showed NO significant difference in cartilage-defect change between groups. Culture-expanded cells of this kind are a drug in the United States and are not available outside a trial.

   Kim KI, et al. — Clinical Efficacy and Safety of the Intra-articular Injection of Autologous Adipose-Derived Mesenchymal Stem Cells for Knee Osteoarthritis: A Phase III, Randomized, Double-Blind, Placebo-Controlled Trial.. American Journal of Sports Medicine, 2023. DOI: 10.1177/03635465231179223.

4. RESTORE, the largest and most rigorously blinded placebo-controlled PRP trial in knee OA (n=288, participant-, injector- and assessor-blinded), gave three weekly injections of a commercial leukocyte-poor PRP or saline. At 12 months the change in knee pain was -2.1 vs -1.8 points (difference -0.4; 95% CI -0.9 to 0.2; P=.17) and the change in medial tibial cartilage volume was -1.4% vs -1.2% (difference -0.2%; P=.81). Twenty-nine of 31 prespecified secondary outcomes showed no between-group difference. The authors concluded the findings do not support the use of PRP for knee OA.

   Bennell KL, 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.

5. The largest head-to-head trial of cell-based orthobiologics to date randomised 480 patients with KL II-IV knee OA across four arms: autologous bone marrow aspirate concentrate, autologous adipose stromal vascular fraction, allogeneic umbilical cord tissue-derived MSCs, and a corticosteroid injection control. At 12 months NONE of the three orthobiologic injections was superior to another or to the corticosteroid control on either co-primary endpoint (VAS pain, KOOS pain), and none of the four groups showed a significant change in MRI osteoarthritis score from baseline. No procedure-related serious adverse events were reported.

   Mautner K, et al. — Cell-based versus corticosteroid injections for knee pain in osteoarthritis: a randomized phase 3 trial.. Nature Medicine, 2023. DOI: 10.1038/s41591-023-02632-w.

6. The 2025 Cochrane review of stem cell injections for knee osteoarthritis pooled 25 randomised trials (1,341 participants) and found that, compared with placebo injection, stem cell injection MAY slightly improve pain (1.2 points better on a 0-10 scale, 7 studies, 445 participants) and function (14.2 points better on a 0-100 scale, 7 studies, 432 participants) up to six months - both rated LOW-certainty evidence, downgraded for indirectness (cell source, preparation and dose varied across studies) and suspected publication bias, since up to three larger RCTs were conducted and withdrawn before reporting results. Radiographic progression was not assessed in any included study.

   Whittle SL, et al. — Stem cell injections for osteoarthritis of the knee.. Cochrane Database of Systematic Reviews, 2025. DOI: 10.1002/14651858.CD013342.pub2.

7. A Bayesian network meta-analysis of 48 Level I-II randomized trials (9,338 knees) with a minimum 6-month follow-up ranked the four commonest intra-articular injections. HA and PRP both significantly improved pain versus placebo; HA, PRP and BMAC all significantly improved function versus placebo. SUCRA rankings were PRP 91.54, BMAC 76.46, HA 53.12, corticosteroid 15.18 and placebo 13.70 - corticosteroid ranked barely above placebo at six months and beyond.

   Jawanda H, et al. — Platelet-Rich Plasma, Bone Marrow Aspirate Concentrate, and Hyaluronic Acid Injections Outperform Corticosteroids in Pain and Function Scores at a Minimum of 6 Months as Intra-Articular Injections for Knee Osteoarthritis: A Systematic Review and Network Meta-analysis.. Arthroscopy, 2024. DOI: 10.1016/j.arthro.2024.01.037.

8. A network meta-analysis restricted to LARGE randomized trials (at least 100 patients per group; 57 RCTs, 22,795 participants, 18 intra-articular interventions) found treatment effects were consistently larger in the 35 high-risk-of-bias trials than in the 22 low/unclear-risk trials. In the main analysis excluding high-risk trials, triamcinolone had the highest probability of exceeding the minimal important difference at weeks 2 and 6; hyaluronic acid had no effect on pain (SMD -0.04, 95% CrI -0.19 to 0.11, 11 trials) but higher odds of dropouts due to adverse events (OR 2.01) and of serious adverse events (OR 1.86). The effects of 16 of the 18 interventions were smaller than the MID and most were consistent with placebo effects.

   Pereira TV, et al. — Effectiveness and safety of intra-articular interventions for knee and hip osteoarthritis based on large randomized trials: A systematic review and network meta-analysis.. Osteoarthritis and Cartilage, 2025. DOI: 10.1016/j.joca.2024.08.014.

9. FDA states verbatim of stem cell products, stromal vascular fraction (adipose-derived cells), umbilical cord blood, Wharton's jelly, amniotic fluid and exosome products: '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, and 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.