Mosaicplasty includes implantation of multiple cartilage plugs where in the defect size is large.
Osteochondral Allograft Transplantation
An allograft is considered when the cartilage defect is much bigger that cannot be covered with an auto-graft. This procedure is typically done by an open incision. For this procedure, a tissue graft is taken from a cadaver donor, prepared and sterilized in a laboratory. Then the tissue is checked for any possible transimission of diseases. It is shaped to fit the exact contour of the defect and then press fit into place.
Mosaicplasty type osteochondral autograft transplantation procedure.
Similar to micro-fracture, Drilling, stimulates the production of healthy cartilage. With the use of an arthroscope and a surgical drill, multiple small holes are done through the injured area in the sub-chondral bone. The healing response is created by penetrating into the sub-chondral bone .
Disadvantages: - Less precise than micro-fracture heat from the drill may cause potential injury to adjacent tissues
Normal healthy articular cartilage in the knee (left). A large cartilage defect in the knee joint surface (center). During microfracture, an awl is used to penetrate the defect (right)
Abrasion arthroplasty is fairly similar to drilling. High speed burrs are used instead of drills or wires, to remove the damaged cartilage and reach the subchondral bone.
Bone Marrow Aspirate Concentrate
This is a minimally invasive procedure where in the fluid is taken from bone marrow. This fluid contains stem cells that can help the healing of some bone and joint conditions. These Stem cells help with bone healing, cartilage repair and new blood vessel growth, thus helping to treat various conditions like Bone marrow removal from the pelvis of a patient delayed union or nonunion of bone fractures, cartilage damage, osteonecrosis, chronic tendon problems or chronic wounds. This method is avoided in patients who have malignancy or infection.
Bone marrow removal from the pelvis of a patient
Brief Description of Procedure
The procedure is done under local/ general anesthesia. A needle is used to remove bone marrow from within the bone.
Common site for the marrow aspirate is pelvis usually on the same side as that of foot or ankle procedure.
The sample of bone marrow is taken and then run down in a centrifuge , which seperates the cells, resulting in a high concentrated liquid, rich in stem cells.This high concentrated liquid is then injected directly into the cartilage surgery site.
The treatment options for articular cartilage injuries
Some patients with an articular cartilage injury improve with conservative treatment. The treatment includes exercises, use of anti-inflammatory medications (NSAIDs). The exercise may include a program you can do at home or formal physical therapy. Depending on the extent of the damage, some patients get better with these treatments and do not require surgery. If patients do not get better with conservative therapy, or have a large articular cartilage lesion, surgery may be necessary.
Surgical treatment of articular cartilage injuries
The surgery for articular cartilage injuries depends on the extent of the damage. There are several surgical options, and which procedure is best depends on several factors. These factors include the patient´s age and activity level, the size of the lesion, and the chronicity (age) of the lesion.
Surgical options include
- Smoothing of the lesion and removing loose edges only (debridement)
- Techniques to stimulate scar cartilage to grow into the lesion (microfracture)
- Techniques to replace the lesion with new cartilage (osteochondral autografts,
osteochondral allografts, or autologous chondrocyte implantation).
Debridement of the articular cartilage
Debridement is performed by using small arthroscopic instruments, such as a mechanical shaver, to smooth the cartilage edges. This is performed so that there are no loose edges to irritate the joint, and to prevent the area of damage from expanding.
The microfracture technique
Microfracture is a technique to attempt to repair damaged articular cartilage. Small holes are made in the denuded bone in order to allow blood and marrow healing elements into the area of missing cartilage. This technique allows scar cartilage (fibrocartilage) to fill the area where the cartilage is missing. This technique is easy to perform and can create good results in a lot of patients. However, since the cartilage is scar cartilage, it may not be as durable as other techniques to restore cartilage defects. Microfracture can be performed during an arthroscopy, and no other incision or surgery is needed.
An osteochondral autograft is a technique to take a small piece of cartilage and bone from one area of the knee and put it in the area that the cartilage is missing. The cartilage is taken from an area in the knee that having minimal stress, so it is thought that patients do not have symptoms due to piece of cartilage loss.This technique can be very effective for small areas of cartilage damage in weight bearing areas. An osteochondral autograft can often be performed by arthroscopic techniques, but sometimes requires an open incision on the knee.
Autologous chondrocyte implantation (ACI)
Autologous chondrocyte implantation (ACI formerly referred to as autologous cartilage transplantation or ACT) is an approach that has been used to treat defined, symptomatic knee cartilage defects.
The aim of this treatment is to enable the regeneration of hyaline or hyaline like cartilage, thereby restoring normal joint function.
ACI comprises a series of procedures.
- Chondrocytes are harvested arthroscopically from the edge of the affected knee joint.
- The cells are cultured for a few weeks to expand the cell population .
- Then, in a second surgical procedure, the cultured chondrocytes are implanted into areas denuded of cartilage
by disease or injury. Each damaged area is carefully debrided and covered with a periosteal tissue flap or a
collagen membrane, beneath which the autologous cells are injected.