# What to know when worn cartilage leaves a joint sore *Cartilage Explained | Regenerative Medicine Peoria* > A plain regenerative medicine Peoria guide to cartilage wear, morning stiffness, helpful movement and reasons to get a joint checked. ## What to notice after you've been sitting Your first steps may feel stiff, then loosen as you cross the kitchen. Later, stairs or a long walk might bring the ache back. Cartilage is the smooth, slippery layer over the bone ends inside your joint. It helps those bone ends move against each other with less rubbing. ## What to do when the joint starts stiff Begin with gentle bends and a slow walk before asking much of the joint. There's no call for a hard workout just to learn whether motion helps. Some stiffness after sitting can come with ordinary wear. Soreness that turns sharp, catches the joint, or changes your walk needs an exam. Stronger muscles can carry more of the work around the sore joint. They won't replace worn cartilage, but they may make daily movement easier. ## What to change when activity brings the ache back Shorten the activity instead of stopping all movement. Flatter ground, fewer stairs, or a lower reach may let the joint settle sooner. On a Sunrise Mountain descent, your knee stays bent and works harder than it did on the climb, so a shorter outing may leave less soreness when you get home. You don't have to quit the trail. Notice whether the ache lasts for hours or changes the way you walk. If you aren't back to normal by morning, the activity may be too much. ## When to have the joint looked at Call the doctor when several days of small changes haven't eased the ache. Say where it hurts and show which movements make it worse. The exam matters because similar aches can have different causes. Earlier X-rays, therapy notes, and the names of your medicines can save time. After a fall, get prompt care if the joint won't work or weakness begins. Sudden heat, swelling, and fever together mean you need urgent help. ## Sources 1. A concise review of mesenchymal stem cells for functional cartilage tissue engineering sets out the underlying problem: articular cartilage is avascular and has very limited intrinsic repair capacity, which is precisely why engineered and cell-based approaches are being pursued - and why building tissue that matches native articular cartilage in composition and mechanical function remains an unsolved engineering problem rather than a delivered clinical product. Tan AR, et al. — [Concise Review: Mesenchymal Stem Cells for Functional Cartilage Tissue Engineering: Taking Cues from Chondrocyte-Based Constructs.](https://pubmed.ncbi.nlm.nih.gov/28177194/). *Stem cells translational medicine*, 2017. DOI: 10.1002/sctm.16-0271. 2. The SUMMIT randomized trial treated 144 patients (mean age 33.8, mean lesion 4.8 cm2) with at least one symptomatic focal cartilage defect (Outerbridge III/IV, >=3 cm2) of the femoral condyle or trochlea. Matrix-applied characterized autologous cultured chondrocytes (MACI) improved KOOS pain (37.0 to 82.5) and function significantly more than microfracture (pain 35.5 to 70.9) at 2 years, with histological and MRI assessment of the repair tissue. This is what a positive cartilage-repair trial looks like - in young patients with a discrete hole, not a worn joint. Saris D, et al. — [Matrix-Applied Characterized Autologous Cultured Chondrocytes Versus Microfracture: Two-Year Follow-up of a Prospective Randomized Trial.](https://pubmed.ncbi.nlm.nih.gov/24714783/). *The American journal of sports medicine*, 2014. DOI: 10.1177/0363546514528093. 3. Eighty patients with a single symptomatic chronic femoral condyle cartilage defect were randomized to autologous chondrocyte implantation or microfracture and followed 14-15 years. No significant difference in clinical scores emerged at long-term follow-up; there were 17 failures in the ACI group versus 13 in the microfracture group and more total knee replacements after ACI (6 versus 3). Fifty-seven percent of surviving ACI patients and 48% of surviving microfracture patients had radiographic early osteoarthritis (KL >=2). Knutsen G, et al. — [A Randomized Multicenter Trial Comparing Autologous Chondrocyte Implantation with Microfracture: Long-Term Follow-up at 14 to 15 Years.](https://pubmed.ncbi.nlm.nih.gov/27535435/). *The Journal of bone and joint surgery. American volume*, 2016. DOI: 10.2106/JBJS.15.01208. 4. MACI (autologous cultured chondrocytes on a porcine collagen membrane, Vericel; STN BL 125603) IS an FDA-LICENSED cell therapy - and its approved indication is narrow and specific: repair of symptomatic, single or multiple FULL-THICKNESS cartilage defects OF THE KNEE, with or without bone involvement, in adults. It is not approved for osteoarthritis. The existence of one licensed cartilage cell therapy for focal defects is the sharpest available way to show what a licensed 'regeneration' product actually looks like, and how far it is from an injection for a worn joint. US Food and Drug Administration, Center for Biologics Evaluation and Research — [MACI (autologous cultured chondrocytes on porcine collagen membrane)](https://www.fda.gov/vaccines-blood-biologics/cellular-gene-therapy-products/maci-autologous-cultured-chondrocytes-porcine-collagen-membrane). *FDA*, 2024. ## What to ask about your sore joint Take your questions, health history, and earlier X-rays or scans. You'll want clear answers about the exam, likely relief, cost, and follow-up. Talk to the clinic team: --- What the soreness may mean and what you can do next. Straight talk about lasting joint soreness, simple care, urgent symptoms and treatment choices in Peoria, Arizona. Useful information on joint soreness, simple care, warning signs and local choices in Peoria. This site is owned by the owners of the QC Kinetix Phoenix-area clinics. © 2026 Peoria Joint Material. Educational information only; not a diagnosis or medical advice.