SÁNCHEZ, M., J. AZOFRA, E. ANITUA, I. ANDÍA, S. PADILLA, J. SANTISTEBAN, and I. MUJIKA. Plasma Rich in Growth Factors to Treat an Articular Cartilage Avulsion: A Case Report. Med. Sci. Sports Exerc., Vol. 35, No. 10, pp. 1648–1652, 2003.
Introduction: The application of an autologous plasma rich in growth factors is beneficial in restoring connective tissues, as shown by clinical evidence in oral surgery and more recently in arthroscopic anterior cruciate ligament reconstruction and two cases of ruptured Achilles tendon in professional athletes. This is attributed to the slow delivery of growth factors from harvested platelets that have been activated by endogenous thrombin promoted by the addition of calcium chloride.
Purpose: This case report describes a new application of this therapy in the arthroscopic treatment of a large, nontraumatic avulsion of articular cartilage in the knee of an adolescent soccer player.
Methods: After arthroscopic reattachment of the large (>2 cm) loose chondral body in its crater in the medial femoral condyle, autologous plasma rich in growth factors was injected into the area between the crater and the fixed fragment.
Results and Conclusion: Despite the extremely poor prognosis of the case, complete articular cartilage healing was considerably accelerated, and the functional outcome was excellent, allowing a rapid resumption of symptom-free athletic activity. This technique opens new perspectives for human tissue regeneration.
Avulsions of articular cartilage are not uncommon among athletically active children and adolescents. As in cases of osteochondritis dissecans, the medial femoral condyle of the knee joint is the most commonly affected area, and although the etiology of this condition remains speculative, repetitive microtrauma is considered to be associated with it (1,12,22,25). Patients with open distal femoral physis usually have a more favorable prognosis for healing with nonoperative treatment, but not all lesions in the skeletally immature patient heal without operative intervention, and surgical treatment is indicated for detached lesions (2,8,12,20,27). Given its lack of blood supply, lymphatic drainage, or neural elements, articular cartilage possesses a limited capability to regenerate after significant mechanical destruction of the cells and collagen scaffold (6,7,18). Recent reports in animal models suggest that the process of cartilage healing in vivo may be improved by growth factors, which are small proteins synthesized both by local cells at the injury site and by infiltrated blood-borne inflammatory cells. These factors stimulate cell proliferation, migration, differentiation, and matrix synthesis and can affect chondrocyte metabolism, chondrogenesis, and improve cartilage healing in vivo (7,9,10,14,17,18,26).
Growth factors could therefore be considered suitable tools to enhance cartilage repair. However, the most appropriate way to use these growth factors is not known. Our work is based on the use of an autologous plasma rich in growth factors (PRGF) obtained from the patient’s own blood by means of a simple procedure. Our hypothesis is that the presence of PRGF in the surgical site accelerates the regeneration of local tissues by a mechanism that reproduces the initial physiological steps of tissue repair: upon activation, platelets aggregate producing a clot, and secrete a variety of cytokines, including adhesive proteins and growth factors such as platelet-derived growth factor (PDGF), transforming growth factor beta (TGF-β), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), insulin-like growth factor I (IGF-I), and epidermal growth factor (EGF). These substances act on local cells inducing specific responses.
Until now, autologous PRGF has been shown to enhance and accelerate soft tissue repair and bone regeneration in the preparation of future sites for dental implants (3,4), and to enhance postsurgery healing and remodeling of anterior cruciate ligament grafts (23) and ruptured Achilles tendons in professional athletes (unpublished observations). These successful clinical results, along with the above-mentioned observations from animal models, provided a rationale for the application of PRGF in a case of arthroscopically treated avulsion of articular cartilage in the knee joint, in an attempt to accelerate articular cartilage healing and complete functional recovery.
The purpose of this report was to describe a novel application of autologous PRGF in the arthroscopic treatment of a large, nontraumatic avulsion of knee articular cartilage, which appeared to be effective in enhancing and accelerating healing, hence functional recovery, in an adolescent soccer player. In conformance with the policy of the American College of Sports Medicine, the subject’s parents provided written informed consent to undergo and publish the following medical procedures, which were approved by the Ethics Committee of the Universidad del País Vasco-Euskal Herriko Unibertsitatea.