Articular cartilage is a tough layer that gives the ends of the bones a smooth shear-resistant bearing surface. Articular cartilage is also referred to as ‘hyaline’ cartilage.
The term chondral injury is often used for a defect that only involves the cartilage surface and osteochondral when it also involves the underlying bone. Chondromalacia is another term often used when articular cartilage becomes damaged.
Articular cartilage damage can range from acute traumatic defects with healthy surrounding cartilage to degenerative lesions seen after repeated trauma where surrounding cartilage is of less good quality and ultimately, at the other end of the spectrum, fully established knee osteoarthritis.
Symptoms & Diagnosis
You may experience activity-related pain and swelling. Mechanical symptoms such as catching and locking can occur especially if there are loose floating pieces of cartilage. Your knee may occasionally buckle or give way and you may hear crepitus on knee movements.
Clinical assessment may be supplemented with standing x-rays and a MRI scan. Sometimes, MRI scans may not reliably demonstrate articular cartilage defects and these are identified at knee arthroscopy. The mechanical alignment and stability of your knee is also assessed.
Articular cartilage lacks blood vessels, nerves and lymphatic tissue. Thus, it has a poor ability to self-repair post injury and treating cartilage injuries can be a challenge.
Treatment can depend on many factors including the location and size of the defect, your symptoms, limb alignment, stability and the presence of osteoarthritis.
Non-operative management can include physiotherapy-led rehabilitation, activity modification, injection treatments or an unloader brace.