The three procedures listed below (autologous chondrocyte transplantation [ACT], osteochondral allograft transplantation, and osteochondral autograft transplantation [OATS/mosaicplasty] of the knee) , are considered medically necessary when the specific inclusion criteria are met.

• Autologous chondrocyte transplantation (ACT)
  Autologous chondrocyte transplantation of the knee (27412, 27599, S2112) is medically necessary for the repair of symptomatic, cartilaginous defects of the femoral condyle (medial, lateral, or trochlear) caused by acute or repetitive trauma in individuals who have had an inadequate response to a prior arthroscopic or other surgical repair procedure and who meet all of the following criteria:

ACT involves the culture of healthy chondrocytes that have been harvested from the patient's own knee.  The charges for the culturing component of the procedure (J7330) should be submitted as part of the facility expense.

• Osteochondral allograft transplantation
  Osteochondral allograft transplantation of the knee (27415, 29867) is medically necessary when all of the following criteria are met:

• Osteochondral autograft transplantation (OATS/mosaicplasty)
  Osteochonral autograft transplantation (27416, 29866) of the knee is medically necessary when all of the following criteria are met:

Autologous chondrocyte transplantation, osteochondral allograft transplantation, and osteochondral autograft transplantation of the knee are considered not medically necessary when any of the following conditions are present:

These procedures are considered not medically necessary when the specific criteria are not met or when performed to repair chondral defects of other body areas (e.g., osteochondral autograft of the talus [ankle], 28446).  A participating, preferred, or network provider cannot bill the member for the denied service.

Description

Hyaline cartilage is a flexible, elastic tissue that covers the articular surface of the knee and allows smooth articulation of the joint.  Focal chondral (cartilage) defects of the knee, either due to trauma or other conditions such as osteochondritis dissecans, often fail to heal on their own and may be associated with pain, loss of function, disability, and the long-term complication of osteoarthritis.  These manifestations can severely impair an individual's activities of daily living and adversely affect quality of life.  Procedures intended primarily to achieve symptomatic relief of chondral defects include debridement (removal of debris and diseased cartilage), lavage (saline washout of the knee), and physical medicine (rehabilitation).  There are other procedures that are intended to repair the articular surface.  The ideal joint resurfacing technique would eliminate symptoms, restore normal biomechanics of the knee joint, and prevent the long-term emergence of osteoarthritis and the necessity for total knee arthroplasty.  Various methods of cartilage resurfacing have been investigated to achieve symptomatic relief and repair the articular surface.  These include marrow-stimulation techniques such as subchondral drilling, microfracture, and abrasion arthroplasty, all of which are considered standard therapies and attempt to restore the articular surface by inducing the growth of fibrocartilage into the chondral defect.  Fibrocartilage, however, does not share the same biomechanical properties as articular hyaline cartilage.  Fibrocartilage is generally considered less durable and mechanically inferior to articular cartilage.  Debridement and rehabilitation may be performed in conjunction with any of these conventional cartilage repair procedures as well. 

In contrast, autologous chondrocyte transplantation (ACT) attempts to regenerate articular cartilage in the affected area and thereby restore function.  ACT is the implantation of autologous cultured chondrocytes that have been harvested from a non-weight-bearing area of the patient’s knee.  These healthy chondrocytes are then grown in a culture medium.  Weeks later, the chondral defect is surgically removed.  The area is covered with a small bone flap and the cultured chondrocytes are transplanted under the bone flap. 

Osteochondral allograft and autograft transplantations are also used in the treatment of individuals with symptomatic, disabling articular cartilage injury or disease in order to improve joint function and decrease pain.  Osteochondral allograft transplantation involves the transplantation of a carefully-fitted graft of fresh or cryopreserved articular cartilage and attached subchondral bone to a damaged region of the articular surface of a joint.  The graft tissue for an allograft is obtained from a donor.  The goal is to provide viable chondrocytes and supporting bone that will be sufficient to maintain the cartilage matrix, and thereby relieving pain and reducing further damage to the articular surface of the joint.  Osteochondral allografting can provide significant relief of pain and improved joint function for individuals with joint cartilage defects.  There is some degree of concern, however, that cryopreservation may decrease the viability of cartilage cells.  Additionally, allografts can be difficult to obtain and there is concern regarding the transfer of infectious diseases from the donor.  For these reasons, autologous osteochondral transplantation has become an option in order to increase the survival rate of the grafted cartilage and to eliminate the risk of disease transmission.  Autologous osteochondral transplantation involves the harvesting of graft tissue from various non-weight-bearing sites in the patient’s own knee.  Autologous grafts may be limited by the small amount of available tissue area within the joint.  In an effort to extend the amount of available donor tissue, multiple, small osteochondral cores may be harvested from multiple sites in the knee.  These grafts are then transplanted into the area involving the cartilage defect in order to restore the articular surface of the bone. 

Mosaicplasty and the osteochondral autograft transplantation system, or (OATS®) procedure are two forms of autologous osteochondral grafting.  The mosaicplasty procedure consists of harvesting cylindrical bone-cartilage grafts and transplanting them into focal chondral or osteochondral defects in the knee.  After excision of the chondral lesion, an abrasion arthroplasty is performed to refresh the bone base of the chondral defect.  Multiple individual osteochondral cores are harvested from the donor site, typically from a peripheral non-weight-bearing area of the femoral condyle.  The grafts are press-fit into the lesion in a mosaic-like fashion within the same-sized drilled recipient tunnels.  The use of multiple grafts in the mosaicplasty technique allows more tissue to be transplanted and permits contouring of the new joint surface.  The resultant surface consists of transplanted hyaline cartilage and fibrocartilage arising from the abrasion arthroplasty.  The fibrocartilage is thought to provide “grouting” between the individual autografts.  Mosaicplasty may be performed with either an open approach or arthroscopically if the lesion is small and not more than 4 to 6 grafts are needed.

The OATS procedure is similar to mosaicplasty, involving the use of a larger, single osteochondral autograft that usually fills an entire defect.  It is often performed to repair chondral defects that are also associated with chronic tears of the anterior cruciate ligament (ACL).  The OATS procedure is performed using an arthroscopic approach that can provide access to both the ACL for reconstruction and performance of the autograft. 

Although mosaicplasty and OATS may use different instrumentation, the underlying principle is similar; i.e., the use of multiple osteochondral cores harvested from a non-weight-bearing region of the femoral condyle and autografted into the chondral defect.  In osteochondral autografting, the harvesting and transplantation can be performed during the same surgical procedure.

NOTE:

This policy is designed to address medical guidelines that are appropriate for the majority of individuals with a particular disease, illness, or condition. Each person's unique clinical circumstances may warrant individual consideration, based on review of applicable medical records.

This medical policy may not apply to FEP.  Medical policy is not an authorization, certification, explanation of benefits or a contract.  Benefits are determined by the Federal Employee Program.

Covered Diagnosis Codes

717.1
717.2
717.3
717.40
717.41
717.42
717.43
717.49
717.5
717.6
717.7
717.81
717.82
717.83
717.84
717.85
717.89
717.9
732.7