The ends of the femur, tibia, and undersurface of the patella (kneecap) – the knee bones – are capped with a smooth surface, which is called articular cartilage. Cartilage protects the ends of bone. It can withstand a significant amount of impact and is significantly smoother than ice, which allows smooth motion in the knee joint. An articular cartilage injury (or “chondral” injury) may occur following a twisting injury to the knee, a direct blow to the knee, or wear and tear as a one ages. Small pieces of articular cartilage can break off and float around in the knee as loose bodies, causing locking, catching and/or swelling.
- Knee swelling
- Instability with walking, turning and pivoting
- Catching or locking in the knee
Diagnosis And Treatment
Dr. Keller considers each patient’s symptoms, as well as a detailed physical examination, x-rays, and usually and MRI of the knee to make the diagnosis. MRI is a very important part of the evaluation because many cartilage injuries are associated with bone injury and bone swelling. Dr. Keller can identify bone swelling and injury on an MRI, but usually not on x-rays.
Some patients with cartilage injuries can be treated with a combination of activity modification and a focused physical therapy program. Physical therapy focuses on maintaining knee range of motion and strengthening certain muscle-tendon unit that provide stability to the knee, such as the quadriceps and hamstrings. Other options for non-surgical management include oral anti-inflammatories, activity modification, as well as injections. There are several types of injections that may help alleviate symptoms, including steroid injections, visco-supplementation injections, and platelet-rich plasma (PRP) or stem cell injections.
Some patients with persistent symptoms or larger defects may require surgery. When patients sustain an injury to articular cartilage and the bone underneath the cartilage, they require a certain type of treatment. Other patients with isolated cartilage injuries can be treated with different techniques. In those patients who have larger, more advanced damage to articular cartilage in one part of the knee, the best surgical option is usually partial knee replacement. In those patients with advanced cartilage damage (“arthritis”) in multiple areas in the knee, the best surgical option is total knee replacement.