1. Aetna considers osteochondral autografts medically necessary for repair of small (less than or equal to 1 cm2) focal chondral defects of articulating cartilage of the leg (ankle, knee, hip) that are causing significant symptoms that have not been relieved by appropriate non-surgical therapies.

2. Aetna considers all of the following procedures experimental and investigational because their effectiveness has not been established:

   1. Osteochondral autograft transplantation to repair chondral defects of the elbow, shoulder, or other joints;
   2. Autologous osteochondral mosaicplasty in the treatment of articular cartilage defects/lesions;   
   3. Osteochondral autograft transfer system (OATS) in the treatment of articular cartilage defects/lesions;   
   4. Hybrid autologous chondrocyte implantation/OATS technique for the treatment of osteochondral defects.

Note: Osteochondral autograft using a single small plug for a small lesion is eligible for coverage.  On the other hand, mosaicplasty and the OATS procedure entail broad resurfacing of larger areas with multiple plugs of autogenous articular cartilage.  These procedures are considered experimental and investigational, thus ineligible for coverage.

See also: CPB 247 - Autologous Chondrocyte Implantation; CPB 364 - Allograft Transplants of the Extremities; and CPB 411 - Bone and Tendon Graft Substitutes and Adjuncts.

Articular cartilage damaged through acute or chronic trauma or osteochondritis dissecans has limited ability to regenerate, resulting in persistent joint line pain, recurrent synovitis and altered joint mechanics most commonly in weight-bearing joints. Loose bodies may develop, which may then cause joint destruction, restricted mobility and/or locking. Long standing severe damage to the articular cartilage can lead to debilitating osteoarthritis, which ultimately may require a total knee arthroplasty. Current therapeutic options include lavage and debridement, which may offer pain relief for up to several years, but offer no prospect of long-term cure. Similarly, marrow-stimulation techniques such as drilling or microfracture of the subchondral bone of cartilage lesions and abrasion arthroplasty fail to provide long-term solutions because these procedures usually promote the development of fibrocartilage, which lacks the durability and many of the mechanical properties of the hyaline cartilage that normally covers articular surfaces.

Osteochondral autografts have been examined as an alternative to allografts for the treatment of osteochondral defects.  Two related procedures have been investigated: (i) mosaicplasty, and (ii) the osteochondral autograft transfer system (OATS).  Mosaicplasty is a relatively new, reconstructive bone grafting procedure for the treatment of articular defects of the knee, ankle and hip. In general, treatment of articular defect of the knee by mosaicplasty entails transplantation of small cylindrical osteochondral grafts (4 to 10 mm in diameter, 15 to 20 mm deep) from the less weight-bearing periphery of the femoral condyles at the level of the patello-femoral joint, and transplanting them in a mosaic-like fashion into a prepared defect site on the weight-bearing surfaces of the same knee. Its goal is to produce a smooth gliding articular surface of hyaline or hyaline-like cartilage in weight-bearing surfaces of the knee. Mosaicplasty is carried out either by an open approach or arthroscopically if the defect/lesion is small and not more than 4 to 6 grafts are needed. Both open and arthroscopic mosaicplasty require a relatively short rehabilitation period - normal daily activity can be allowed after 5 to 8 weeks.

Although animal studies and subsequent clinical trials have demonstrated the survival of transplanted hyaline cartilage, there are no studies comparing the results of mosaicplasty with other established procedures. Also, there is a lack of long-term follow-up data on the durability of the repaired and transplanted tissues. It is unclear whether mosaicplasty can prevent further deterioration in the affected articular cartilage. Furthermore, there are insufficient long-term follow-up data concerning potential complications associated with multiple donor sites.

In a review on biological treatment of joint cartilage damage, Tyyni and Karlsson (2000) noted that different treatment methods have been developed in an attempt to restore the function of the injured joint and to prevent further deterioration in the articular cartilage. Some of these methods have produced promising results in clinical studies, but further research is necessary to establish their efficacy and indications for treatment. Today, no controlled studies that compare these different methods are available. This observation is in agreement with that of Arokoski and colleagues (2000), who stated that many surgical extra- and intra-articular procedures have been used for the treatment of osteoarthrosis. Although some of the new methods such as autologous chondrocyte transplantation and mosaicplasty have shown good preliminary clinical results, a review of the literature indicates that these methods are still considered experimental and more controlled studies are needed.

In a review on treatment osteochondral injuries of the knee, Cain and Clancy (2001) stated that the treatment of osteochondral fractures and osteochondral lesions in the knee is controversial. Although the results of many reconstructive procedures (e.g., autologous osteochondral mosaicplasty and osteochondral allograft transplantation) are quite encouraging with early follow-up, the ultimate goal is to prevent long-term degenerative arthritis. Only well-designed prospective studies with long-term follow-up will determine the effectiveness of these procedures in reaching the ultimate goal.

In a review on management of osteochondral injuries of the knee, Alleyne and Galloway (2001) stated that the management of articular cartilage lesions has yet to reveal a “right answer”, and that long-term follow-up studies of all of the techniques reviewed are needed to give definitive answers about the durability of the repaired and transplanted tissues.

In a review on mosaicplasty for the treatment of osteochondral defects of the ankle joint, Mendicino and associates (2001) stated that this procedure shows excellent promise for use in the ankle and warrants larger investigational studies to assess outcomes. In a randomised, clinical trial (n = 100), Bentley et al (2003) reported significant superiority of autologous chondrocyte implantation over mosaicplasty for the repair of articular defects in the knee. The results for autologous chondrocyte implantation are comparable with those in other studies, but those for mosaicplasty suggest that its continued use is of dubious value.

Guidelines from the American College of Rheumatology on management of osteoarthritis (OA) of the hip and knee state that autologous osteochondral plugs (mosaicplasty) is being investigated for repair of focal chondral defects, but that this procedure is “not currently indicated in the treatment of patients with OA” (Altman, et al., 2000).

An assessment of mosaicplasty for knee cartilage defects from the National Institute for Health and Clinical Excellence (NICE, 2006) concluded: "Current evidence suggests that there are no major safety concerns associated with mosaicplasty for knee cartilage defects. There is some evidence of short-term efficacy, but data on long-term efficacy are inadequate. In view of the uncertainties about the efficacy of the procedure, it should not be used without special arrangements for consent and audit or research."

The osteochondral autograft transfer system is a procedure employed for medium sized areas of discrete damage (mosaicplasty is employed for even larger but discrete areas of damage). 

The OATS procedure focuses on chondral defects that are associated with chronic tears of the anterior cruciate ligament (ACL), using an arthroscopic approach that can provide access to both the ACL for reconstruction and performance of the autograft. The orthopedic surgeon uses an apple-corer like instrument to core out a circle of damaged cartilage and replaces it with a piece of normal cartilage from a less important part of the same knee. The underlying principal is that the transferred cartilage will grow to cover the edges of the core with proper cartilage cells and not the weaker fibrocartilage cells.

Bobic (1996) reported the results of a case-series study (n = 12) regarding the use of OATS in patients with ACL-deficient knees. The series examined arthroscopic osteochondral autograft transplantation in conjunction with ACL reconstruction using bone-patellar tendon-bone autograft. Eight procedures were primary, and four were revisions of failed synthetic grafts. Chondral lesions in this series ranged from 10 to 22 mm in diameter. Donor site was selected prior to notchplasty, and three to five osteochondral cylinders, 5 to10 mm in diameter, 10 to15 mm long, were harvested. The author stated that improved surgical technique, tubular cutting instruments enabling minimal damage to harvested articular cartilage, and press-fit insertion yielded promising uniform results in 10 of 12 cases with 2 years' follow-up.

Wang (2002) reported a retrospective study of 15 patients with 16 knees who underwent osteochondral autografts for focal full thickness articular cartilage defects of the knee. Two to four years follow-up of these patients showed 80 % good or excellent clinical results. There was no correlation of the clinical results with the underlying diagnoses, including osteonecrosis, osteochondritis dissecans and traumatic cartilage defect, or a size of the lesion smaller than 600 mm2. However, cartilage lesions larger than 600 mm2 were associated with increasing fibrous tissue formation and fissuring between the grafts and the host tissues and poor results. The improvement in symptoms appeared time-dependent, ranging from 6 to 16 weeks, suggesting that post-operative protection of the graft is warranted. There was no radiographic progression of degenerative changes of the knee on the medium-term follow-up.

Although the results of retrospective/case series studies of the OATS procedure are encouraging with early follow-up, well-designed prospective studies with long-term follow-up are needed to ascertain the durability of the repair and transplanted tissues as well as the adequacy of this procedure to prevent long-term degenerative arthritis in patients with osteochondral injuries of the knee. Furthermore, Easley and Scranton (2003) stated that long-term outcome of the OATS procedure for osteochondral lesions of the talus is not yet available.

The majority of the evidence for osteochondral autografting consisted of retrospective/case series studies dealing with chondral lesions of the knee. Furthermore, there are no studies comparing the results of osteochondral autografting with other established therapies (e.g., lavage subchondral drilling, or abrasion arthroplasty). Thus, the available evidence is insufficient to establish the effectiveness of mosaicplasty or OATS for the treatment of articular cartilage lesions.

The BlueCross BlueShield Association Technology Evaluation Center (2003) stated that autogenous osteochondral transplantation (OATS or mosaicplasty) are not established treatments for chondral defects. “Although preliminary reports” of autogenous osteochondral transplantation (OATS or mosaicplasty) “appear favorable, only limited outcome data are available on this technology.”

Sharpe, et al. (2005) reported their 3-year post-operative findings on the use of a combination of autologous chondrocyte implantation (ACI) and the OATS procedure as a treatment option for the repair of large areas of degenerative articular cartilage. Osteochondral cores were used to restore the contour of articular cartilage in 13 patients with large lesions of the lateral femoral condyle (n = 5), medial femoral condyle (n = 7) and patella (n = 1). Autologous cultured chondrocytes were injected underneath a periosteal patch covering the cores. After 1 year, patients had a significant improvement in their symptoms and after 3 years this level of improvement was maintained in 10 of the 13 patients. Arthroscopic examination revealed that the osteochondral cores became well integrated with the surrounding cartilage. These investigators concluded that the hybrid ACI/OATS technique provides a promising surgical approach for the treatment of patients with large degenerative osteochondral defects.

Scheibel and colleagues (2004) performed 8 osteochondral autologous transplantations from the knee joint to the shoulder.  All patients (2 women and 6 men; mean age of 43.1 years) were documented prospectively.  In each patient the stage of the osteochondral lesion was Outerbridge grade IV with a mean size of the affected area of 150 mm2.  All patients were assessed by using the Constant score for the shoulder and the Lysholm score for the knee.  Standard radiographs, magnetic resonance imaging and second-look arthroscopy were used to evaluate the presence of glenohumeral osteoarthritis and the integrity of the grafts.  After a mean of 32.6 months (8 to 47), the mean Constant score increased significantly.  Magnetic resonance imaging revealed good osseo-integration of the osteochondral plugs and congruent articular cartilage at the transplantation site in all but 1 patient.  Second-look arthroscopy performed in 2 cases revealed a macroscopically good integration of the autograft with an intact articular surface.  The authors noted that osteochondral autologous transplantation in the shoulder appears to offer good clinical results for treating full-thickness osteochondral lesions of the glenohumeral joint. However, they also noted that the findings of their study suggest that the development of osteoarthritis and the progression of pre-existing osteoarthritic changes cannot be altered by this technique.

Tsuda and co-workers (2005) reported the use of osteochondral autograft transplantation in 3 cases of non-throwing athletes with osteochondritis dissecans of the capitellum.  Pre-operatively, these patients complained of elbow pain during sports activities (rhythmic gymnastics, table tennis, and basketball, respectively).  Magnetic resonance imaging (MRI) showed a completely separated osteochondral fragment or a full-thickness cartilage defect.  All 3 patients were treated with transplantation of an osteochondral autograft harvested from the lateral femoral condyle.  They returned fully to their sports activities within 6 months of surgery.  The continuity of the cartilage layer between the osteochondral graft and the capitellum was shown on MRI taken at 12 months post-operatively.  The authors believed that osteochondral autograft transplantation provides successful results for non-throwing athletes with end-stage osteochondritis dissecans of the capitellum.

Shimada and associates (2005) stated that the treatment of large, advanced osteochondritis dissecans of the elbow is controversial.  To determine if better results could be obtained using osteochondral autografts, these researchers retrospectively reviewed the results in 10 young athletes (mean age of 14.3 years with a range of 12 to 17 years) who were followed up for a mean of 25.5 months (range of 18 to 45 months).  After abrasion of the fragments, cylindrical osteochondral bone plugs were transferred from a lateral femoral condyle.  They were evaluated clinically by the Japanese Orthopedic Association (JOA) elbow score and radiologically by radio-capitellar congruity.  All patients achieved bony union in 3 months.  The average JOA elbow score was 80.6 points before surgery and improved to 93.8 points at follow-up.  The average percentage of radio-capitellar congruity was 35.7 % before surgery and improved to 64.2 % at follow-up.  Clinical and radiological results were excellent in 8 patients and poor in 2.  Poor results may be dependent on pre-existing osteoarthritis and technical difficulty related to the location of the lesion.  In 8 patients, a durable load-bearing elbow was obtained with this procedure, which made hyaline-like cartilage resurfacing with healthy subchondral bony support possible.  The authors concluded that osteochondral autograft is a reasonable surgical option for an advanced lesion of osteochondritis dissecans of the elbow, although long-term follow-up is needed to ascertain if the early results persist.  The scientific evidence supporting the use of osteochondral autografts to repair the elbow and shoulder consists mainly of single case reports.  Currently available published studies are small, non-randomized, and lack long-term follow-up.  Thus, further investigation is needed to ascertain the clinical value of osteochondral autografts for repairing  the elbow and shoulder.

The Institute for Clinical Effectiveness and Health Policy (Pichon-Riviere, et al., 2006) evaluated the literature on the effectiveness of OATS and mosaicplasty on ankle bone cartilage lesions. The assessment concluded: "There is still not enough evidence available on the efficacy of mosaicplasty or the OATS procedure for the treatment of talus cartilage joint lesions. There is very little published about the assessment of the osteochondral grafting viability. There is not enough evidence determining whether the tissues coming from places that do not carry weight could absorb the stress of weight bearing areas, neither the degree of donor site morbidity. Patient inclusion criteria are not well settled in the literature, and there is no uniform consensus on the procedure's indication. ...Only well designed prospective clinical trials with long follow-ups could determine the efficacy of these procedures to relieve the symptoms caused by osteochondral lesions, improve joint function and achieve the final objective, which is the prevention of secondary arthrosis."

Aurich and colleagues (2008) noted that ankle sprains are one the most common injuries of the lower limb. Fractures, ligamentous lesions, and cartilaginous damage are often associated. Nevertheless, the injury is often mis-judged and concomitant chondral lesions are assessed late. In the case of a symptomatic osteo-cartilaginous lesion of the talus, which can be illustrated by MRI or X-ray, operative intervention is indicated. Methods such as microfracturing, mosaicplasty, and autologous chondrocyte transplantation (ACT) are in clinical use. The latter is well-known and being established as the treatment of choice for large cartilage defects in the knee. Due to the good results in the knee and the technological improvements (three-dimensional tissue constructs seeded with autologous chondrocytes) this method is being increasingly applied for cartilage lesions of the talus. In contrast to the mosaicplasty, donor site morbidity is low and the size of the defect is not a limiting factor. The current studies about ACT of the talus show a stable repair of the defect with mostly hyaline-like cartilage and high patient satisfaction. Therefore, the procedure can be recommended for lesions les than 1 cm2. Concomitant treatment of post-traumatic deformities (malalignment), ligamentous instabilities, and especially the reconstruction of bony defects are compulsory.

In a systematic review, Magnussen et al (2008) examined if ACT or osteochondral autograft transfer yields better clinical outcomes compared with one another or with traditional abrasive techniques for treatment of isolated articular cartilage defects and if lesion size influences this clinical outcome. These researchers performed a literature search and identified 5 randomized, controlled trials and 1 prospective, comparative trial evaluating these treatment techniques in 421 patients. The operative procedures included ACT, osteochondral autograft transfer, matrix-inducedACT, and microfracture. Minimum follow-up was 1 year (mean of 1.7 years; range of 1 to 3 years). All studies documented greater than 95 % follow-up for clinical outcome measures. No technique consistently had superior results compared with the others. Outcomes for microfracture tended to be worse in larger lesions. All studies reported improvement in clinical outcome measures in all treatment groups when compared with pre-operative assessment; however, no control (non-operative) groups were used in any of the studies. The authors stated that a large prospective trial investigating these techniques with the addition of a control group would be the best way to definitively address the clinical questions.