Knee Cartilage Damage: Treatment Options Explained

Why does cartilage damage matter — and why is it hard to heal?

The articular cartilage lining the ends of your knee bones (femur, tibia, and the back of the kneecap) has almost no blood supply. Because cartilage cells cannot easily migrate to an injury site the way they can in soft tissue, spontaneous healing is limited. Even small, focal defects can progress over years if not managed.

Cartilage problems in the knee come in two main forms: - Chondromalacia patellae: Softening and breakdown of the cartilage on the back of the kneecap, common in younger active people and often related to alignment or overuse. - Focal chondral defects: Localized full-thickness or near-full-thickness damage, often from a traumatic event or osteochondritis dissecans (a condition in which a fragment of bone and cartilage partially detaches).

What non-surgical treatments are available?

For focal defects and chondromalacia, non-surgical management is almost always the appropriate starting point and works well for many patients, particularly those with smaller lesions and no mechanical symptoms (locking or giving-way) 1Ref 1Brophy RH, Fillingham YA (2022).AAOS Clinical Practice Guideline Summary: Management of Osteoarthritis of the Knee (Nonarthroplasty), Third Edition.Non-surgical management of knee cartilage conditions including physical therapy as cornerstone; hyaluronic acid injection not recommended due to inconclusive evidence.

Physical therapy is the cornerstone. Strengthening the quadriceps and hip muscles reduces abnormal forces across the joint. Improving lower-limb alignment and movement mechanics can meaningfully reduce symptoms from patellar chondromalacia.

Activity modification: Reducing high-impact loading (running on hard surfaces, deep squatting, jumping) gives the cartilage relief from repeated stress.

NSAIDs (anti-inflammatory medications): Short courses can reduce pain and swelling, though they do not repair the cartilage. They carry gastrointestinal and cardiovascular risks with prolonged use and should be used at the lowest effective dose for the shortest period 2Ref 2MedlinePlus / U.S. National Library of Medicine (2024).Ibuprofen: MedlinePlus Drug Information.NSAID safety considerations including GI and cardiovascular risks with regular use; recommendation to use at lowest effective dose for shortest period.

Intra-articular injections: Corticosteroid injections offer temporary pain relief. Hyaluronic acid injections have mixed evidence; the 2022 AAOS knee osteoarthritis guideline does not recommend hyaluronic acid injections due to inconclusive overall evidence 1Ref 1Brophy RH, Fillingham YA (2022).AAOS Clinical Practice Guideline Summary: Management of Osteoarthritis of the Knee (Nonarthroplasty), Third Edition.Non-surgical management of knee cartilage conditions including physical therapy as cornerstone; hyaluronic acid injection not recommended due to inconclusive evidence. Platelet-rich plasma (PRP) injections are increasingly used but remain investigational.

When is cartilage repair surgery considered?

Cartilage repair is generally considered when a focal defect is causing significant symptoms, the defect is large enough that non-surgical management is insufficient, and there is no widespread arthritis throughout the joint (which would make restoration futile).

An orthopedic surgeon will assess: - Defect size and depth on MRI — small defects may respond to less invasive procedures; larger ones may require more complex reconstruction - Patient age and activity level — younger, more active patients are typically better candidates for restoration procedures - Presence of malalignment — correcting a knee alignment problem (high tibial osteotomy) is sometimes done alongside cartilage repair to redistribute load - Presence of diffuse arthritis — widespread cartilage loss throughout the joint is better addressed by knee replacement than by focal repair

What surgical options exist for cartilage repair?

There is a spectrum of procedures, roughly ordered from less to more complex:

Bone marrow stimulation (microfracture): Small holes are drilled through the bone beneath the defect to release stem cells that form fibrocartilage. Faster recovery but fibrocartilage is less durable than native hyaline cartilage. Best for smaller defects.

Osteochondral autograft transfer (OATS / mosaicplasty): Plugs of bone and cartilage are harvested from a lower-load area of your own knee and transplanted to the defect. Provides native cartilage but is limited by donor availability for larger lesions.

Osteochondral allograft transplantation (OCA): Cadaveric donor cartilage-and-bone plugs fill the defect. Best suited for larger lesions (often >6 cm²). A systematic review of 1,993 patients found OCA produced clinically meaningful Lysholm score improvements (+30.5 points), comparable to other restoration techniques 3Ref 3Nassar JE, Guerin G, Keel T, Russo R, Familiari F, Tollefson LV, LaPrade RF (2025).Autologous chondrocyte implantation, matrix-induced autologous chondrocyte implantation, osteochondral autograft transplantation and osteochondral allograft improve knee function and pain: A systematic review and meta-analysis.All four cartilage restoration techniques (ACI, MACI, OAT, OCA) produce clinically meaningful Lysholm score improvements at mean 57-month follow-up in 1,993 patients; MACI +29.4, OAT +39.7, OCA +30.5 points.

Matrix-induced autologous chondrocyte implantation (MACI): A two-stage procedure in which a biopsy of healthy cartilage is cultured in a laboratory, then re-implanted on a collagen scaffold. MACI produced Lysholm score improvements of +29.4 points in the same systematic review — comparable to OATS (+39.7) and OCA (+30.5) — with all techniques exceeding clinically meaningful thresholds for pain and function at a mean follow-up of nearly five years 3Ref 3Nassar JE, Guerin G, Keel T, Russo R, Familiari F, Tollefson LV, LaPrade RF (2025).Autologous chondrocyte implantation, matrix-induced autologous chondrocyte implantation, osteochondral autograft transplantation and osteochondral allograft improve knee function and pain: A systematic review and meta-analysis.All four cartilage restoration techniques (ACI, MACI, OAT, OCA) produce clinically meaningful Lysholm score improvements at mean 57-month follow-up in 1,993 patients; MACI +29.4, OAT +39.7, OCA +30.5 points.

An orthopedic surgeon with experience in cartilage restoration — typically a sports medicine orthopedist — can evaluate your MRI and help determine which path fits your situation. Gale can help you connect with that specialist.