Arthroscopic Articular Reconstruction of Capitellar Osteochondral Defects

Abstract

Background: Articular reconstruction is recommended for some unstable capitellar osteochondritis dissecans (OCD) lesions. Capitellar osteochondral autograft transplantation (OAT) through an open approach for optimal visualization and perpendicular graft implantation has been advocated. However, arthroscopic capitellar OAT may achieve the same treatment goals with decreased morbidity and ability to treat the entire joint for pathologic changes. Purpose/Hypothesis: The purpose of this study was to assess the ability to resurface the capitellum arthroscopically. The hypothesis was that arthroscopy allows sufficient access to facilitate perpendicular graft placement in most clinically significant capitellar OCD lesions. Study Design: Descriptive laboratory study. Methods: Arthroscopy was performed on 12 fresh-frozen cadaveric elbows. Of the tunnels created, 21 were used in final analysis. A 6-mm osteochondral transplantation bone graft harvester was used to generate perpendicular recipient sites in the capitellar articular surface. Both central (n = 11) and lateral (n = 10) OCD locations were studied. Fluoroscopy was used to measure the angle of the harvest relative to the axis of the humerus and tunnel perpendicularity. Results: Among central and lateral lesions, the average (±SD) degree of perpendicularity achieved was 85.3° ± 2.9° and 85.8° ± 2.5°, respectively. Perpendicular harvests were achieved in central and lateral lesions as high as 74.9° and 80.4°, anterior to the humeral shaft, respectively. No significant relationship was noted between increasing anterior location and ability to attain perpendicular harvests. Achieving perpendicularity in lesions that were more anterior to these values was not possible due to anatomic constraints of the radial head in maximal elbow flexion. Conclusion: Adequate recipient tunnels were created in lesions that were as high as 75° to 80° anterior to the humeral shaft, which encompasses most clinically relevant lesions. Moreover, increasing the anterior position of the lesion did not compromise the ability to generate perpendicular tunnels. The findings of this cadaveric study suggest that most clinically relevant capitellar osteochondral lesions can be successfully resurfaced arthroscopically. Clinical Relevance: This study demonstrates the feasibility of performing an arthroscopic versus open articular reconstruction when indicated for high-grade capitellar OCD lesions. These conclusions afford sports medicine surgeons another tool in the treatment of this challenging condition.