Osteochondral lesions of the knee occur in adolescent athletes with some regularity. A shearing force across the joint causes the cartilage to pull away through its full thickness. Planting the foot on the ground and twisting over the knee is the main mechanism of injury. The force of it may pull away a piece of the underlying bone with the cartilage.
This is a fairly common injury among adolescent athletes. The frequency of this problem does not mean we have the perfect treatment worked out yet. Until recently, the fragments were just removed. That type of treatment at least reduces the pain and stops the knee from giving way or locking up on you.
But it may not be ideal. Leaving a gaping hole in the cartilage sets the patient up for a potential problem years down the road. The defect fills in with a mixture of fibrous cartilage. Since the injury is located on the weight-bearing surface, constant pressure over the area causes further breakdown. Eventually, a degenerative arthritis develops.
Pain, swelling, and knee locking are common symptoms with osteochondral fractures. Leaving the injury untreated isn’t usually an option. Today, scientists are studying better ways to treat the problem.
One possibility is internal fixation of the fragments. Tiny rods made of polyglycolic acid are placed between the torn fragment(s) and the bone. The rods are small bioabsorbable rod-shaped implants. During the healing process, the polyglycolic acid is absorbed and replaced by living tissue.
Only short-term and medium-term results have been reported. But the outcomes look promising. Patients have normal looking X-rays and MRIs as the cartilage heals. There may not even be any thinning of the cartilage when viewed on closer inspection.
Cartilage repair technology is still being developed. A special fibrin glue is also being used in some experiments. This is not available everywhere. Eventually, it may be possible to repair the torn fragments and restore full function of the knee.