Cartilage Repair
Treatment of cartilage injuries depends on many factors. There is the cartilage injury itself plus other issues such as alignment and stability of the joint including potentially patella instability and injuries to other structures in the knee.
Fixation of cartilage injury:
If the cartilage fragment has bone attached to it especially if the injury is acute, it may be possible to fix it back to its original position with metal screws and absorbable bone tacks (internal fixation). The procedure may be done arthroscopically or in combination with a mini-open procedure.
Debridement and marrow stimulation:
Small, loose fragments of cartilage may be removed from the joint and the edges of cartilage from where the injury has occurred are smoothed to a stable margin. If there is a small, full thickness area of cartilage loss, tiny holes in the underlying bone can be made which can allow bone marrow to create a type of fibrocartilage to coat and fill in the defect. This procedure is usually performed arthroscopically.
Cartilage regeneration procedures:
These procedures attempt to enhance cartilage growth in areas of larger cartilage defects. They may include marrow stimulation and/or using the patient’s own healthy cartilage from the surrounding part of the knee to put back into the defect and covering it with scaffold.
Osteochondral implantation procedures:
When there are larger areas of cartilage with underlying bony defects, a block of bone with overlying cartilage can be fashioned and fit into the defect and heal into the underlying bone. The osteochondral block can come from the patient’s own knee (autograft) or from a specially treated donor cadaveric knee (allograft).
Treatment of Osteochondritis Dissecans (OCD)
Initially treatment is non surgical the majority of the time. These include pain relief, activity modification and bracing. Investigations such as Xray, CT and MRI will help to determine if the OCD is stable, healing or unstable. If the OCD does not heal or continues to cause symptoms despite non surgical treatment, usually surgery involves arthroscopic assessment and treatment of the OCD.
OCD drilling – If the OCD is stable, then making tiny holes into the underlying bone marrow can stimulate healing of the OCD.
OCD fixation – When the OCD is unstable, it may be possible to fix the lesion in place with screws and/or bone tacks. This can usually be achieved arthroscopically.
OCD removal – If the OCD is unstable and not large enough to be internally fixed, it may be removed. This is sometimes combined with a marrow stimulation procedure to encourage ingrowth of fibrocartilage. Where there is a larger OCD defect, cartilage regeneration or osteochondral implantation procedures may be appropriate.