Subchondral sclerosis is a term used to describe increased bone density just beneath a joint’s cartilage surface. It is most often reported as an imaging finding on X-ray, CT, or MRI. It commonly appears in joints affected by osteoarthritis, including the knee. It helps clinicians describe how a joint is responding to stress, cartilage loss, or altered load-bearing.

Osteophytes are bony outgrowths that form along the edges of a joint. They are often called “bone spurs,” although they are part of the bone itself. They most commonly develop in joints affected by osteoarthritis, including the knee. Clinicians use the presence and location of Osteophytes as a clue to joint stress and degeneration.

Joint space narrowing is a term used in medical imaging reports to describe a reduced gap between two bones in a joint. It is most commonly discussed when reviewing weight-bearing X-rays of the knee, hip, or hand. In simple terms, it can suggest that the “cushion” of cartilage or meniscus in that joint is thinner or less effective. Clinicians use it as one piece of information when evaluating arthritis, injury effects, and joint degeneration.

Cartilage loss describes thinning, softening, or breakdown of joint cartilage. In the knee, it most often refers to damage to the smooth cartilage covering the femur, tibia, and patella. It is commonly discussed in osteoarthritis, sports injuries, and post-traumatic joint changes. Clinicians use the term to describe a structural finding that may relate to pain, stiffness, and reduced function.

Cartilage degeneration is the gradual breakdown and loss of smooth joint cartilage. It is commonly discussed in knee pain, arthritis, and sports injury care. It describes a tissue change rather than a single test or procedure. Clinicians use the term to explain symptoms, imaging findings, and treatment options.

Chondromalacia patellae is a term for softening and breakdown of cartilage on the underside of the kneecap. It is commonly discussed in the setting of front-of-knee pain and patellofemoral (kneecap–thighbone) problems. Clinicians use it in exams, imaging reports, and arthroscopy findings to describe cartilage changes.

Patellofemoral osteoarthritis is arthritis that affects the joint between the kneecap (patella) and the thigh bone (femur). It involves wear and breakdown of joint cartilage and related changes in the bone and soft tissues around the kneecap. It is commonly discussed in orthopedic clinics, sports medicine, physical therapy, and radiology reports for knee pain. This overview is informational and not medical advice.

Lateral compartment osteoarthritis is arthritis that mainly affects the outer (lateral) side of the knee joint. It involves gradual wear and inflammation in the compartment between the femur (thigh bone) and tibia (shin bone). It is commonly discussed in orthopedic clinics when knee pain is worse on the outside of the knee. It is also used in imaging reports and rehab plans to describe where knee arthritis is most active.

Medial compartment osteoarthritis is wear-and-tear arthritis focused on the inner side of the knee joint. It affects the medial tibiofemoral compartment, where the femur meets the tibia. It is commonly discussed in orthopedic clinics, physical therapy, and sports medicine when evaluating knee pain and stiffness. It is also used in imaging reports to describe where arthritis changes are most prominent.

Tricompartmental osteoarthritis is knee osteoarthritis that affects all three compartments of the knee joint. It is a diagnostic term commonly used in orthopedic clinics, radiology reports, and physical therapy documentation. It helps describe the overall pattern of cartilage wear and joint change across the whole knee. It is often discussed when comparing non-surgical care with knee replacement options.