Fresh Osteochondral Allograft Transplantation Is a Promising Option for Athletes with Osteochondritis Dissecans of the Capitellum

Researchers from Kaiser Permanente found that fresh osteochondral allograft transplantation (FOCAT) demonstrated favorable mid-term outcomes for the resurfacing of osteochondritis dissecans (OCD) lesions of the humeral capitellum. Their findings will be presented by Raffy Mirzayan, MD, FAAOS, study coauthor and orthopaedic surgeon at Kaiser Permanente Baldwin Park Medical Center in Baldwin Park, California, during the AAOS 2025 Annual Meeting in San Diego.

“OCD of the capitellum is a rare condition affecting the elbow of adolescent athletes, mostly in baseball and gymnastics. The treatment for this condition has traditionally consisted of arthroscopic lavage and debridement, as well as microfracture or drilling of the lesion,” Dr. Mirzayan explained to AAOS Now Daily Edition. “We know from the knee literature that microfracture leads to the formation of fibrocartilage containing mostly type I collagen, which is not durable, especially in high-demand settings. In addition, the return-to-sport rates, at the same level as pre-injury and duration of play after returning to sports, have been less than desirable.”

For this study, the surgeons sought to obtain grafts from the costal cartilage of ribs or from the knee for elbow resurfacing with hyaline articular cartilage. “In the United States, grafts from knee are most common, but donor-site morbidity of 8 to 11 percent has been reported in the literature,” Dr. Mirzayan noted. “Because of this reason, I chose to use fresh osteochondral allografts to resurface and reconstruct unstable OCD lesions of capitellum to avoid donor-site morbidity.”

The study reviewed 35 patients who underwent FOCAT for OCD of the capitellum between 2006 and 2022 by a single surgeon. Ninety-four percent of patients had unstable lesions, and all patients had failed nonoperative treatment. The mean age was 16 years (range, 11–32 years), and there were 25 male patients. Most participants were athletes: 24 baseball players, five gymnasts, three cheer/tumbling athletes, and one tennis player. One patient was treated for avascular necrosis from chemotherapy. All patients underwent diagnostic arthroscopy, followed by a mini-open, ligament-sparing approach with grafting (Fig. 1). For 23 patients, a single osteochondral allograft plug was used; 12 patients required 2 plugs.

At a mean follow-up of 92.6 months, Dr. Mirzayan reported, “There was significant improvement in functional outcome scores (Oxford) as well as the Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow (KJOC) Score, which is a validated outcome score for overhead athletes. There was significant reduction in pain.”

Oxford scores improved from 25.5 at baseline to 46.7 at follow-up (P <0.00001), and visual analog scale scores decreased from 7.5 to 0.3 (>P <0.0001). at follow-up, the mean single assessment numeric evaluation score was 90.6. in overhead athletes, kjoc scores increased from 40.8 to 90.6 (>P <0.00001).>

“One hundred percent of baseball players were able to return to sport at same or higher levels as pre-injury and play for at least 2 years. There is no study in the literature that I am aware of with microfracture that has this type of outcome,” Dr. Mirzayan said. “Two baseball players went on to play professional baseball, and two obtained an NCAA Division 1 scholarships for baseball and tennis.”

Sixteen patients (46 percent) underwent postoperative MRI at a mean of 32.6 months. The graft was incorporated in all cases, with maintenance of cartilage surface. Two elbows required subsequent arthroscopy for removal of loose bodies. The authors reported no additional complications.

When asked if he was surprised by any of these findings, Dr. Mirzayan shared, “My expectation was that some or most patients would improve with this procedure, but I did not expect all of the patients to do as well as they did. I used a knee hemicondyle from a donor, as they are more readily available than an upper-extremity graft. I had no issues of matching the radius of curvature of the graft with the recipient site.”

The key clinical takeaway from this study, according to Dr. Mizayan: “FOCAT offers an outstanding solution for athletes who develop this rare yet debilitating condition. I think most surgeons who are not accustomed to using fresh osteochondral allografts may be concerned about infection or risk of disease transmission. Therefore, they may not feel comfortable offering this option to patients and their parents and would rather use osteochondral autograft from the patient’s knee. That concern may be valid, but the risk of disease transmission is less than 1 in 1.5 million.”

The authors noted that surgeons should consider the cost versus benefit of an allograft, as costs can be higher with FOCAT compared with autograft. “However,” Dr. Mirzayan said, “there are smaller pre-cut grafts available that are a fraction of the cost of an entire hemicondyle.”

Paper 395 will be presented during VIPER: Shoulder and Elbow V Papers, 8 a.m. on Thursday in Ballroom 20B.

Dr. Mirzayan’s coauthors of “Fresh Osteochondral Allograft Transplantation of the Capitellum for the Treatment of Osteochondritis Dissecans” are Jonathan Mina Ragheb, Kian Michael Jeshion-Nelson, BS; David O. DeWitt, PA; and Christian Cruz, MD.

Rebecca Araujo is the managing editor of AAOS Now. She can be reached at raraujo@aaos.org.