Figure 1. Anteroposterior radiographic view of elbow.
Figure 2. Magnetic resonance imaging of elbow shows a cyst in the capitellum with joint effusion and loose bodies.
A 14-year-old adolescent presents to the office with a complaint of right-lateral elbow pain for the past 6 months. The teen is accompanied by his parents and denies a known injury to the elbow. The pain has worsened over the last month since baseball season started. He is involved in gymnastics and baseball most months of the year. On physical examination, the patient has tenderness to palpation over the radiocapitellar joint. Range of motion of the elbow is full and equal to the contralateral side. Anteroposterior radiograph of the right elbow (Figure 1) shows a focal radiolucent lesion of the capitellum with flattening of the articular surface. A magnetic resonance imaging of the elbow (Figure 2) reveals a cyst in the capitellum with joint effusion and loose bodies.
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Osteochondritis dissecans (OCD) of the elbow most commonly occurs at the capitellum in adolescent athletes. Gymnasts and baseball players have the highest incidence of OCD of the capitellum, which is likely attributed to compression of the radiocapitellar joint during handstands and overhead throwing.1 The natural history of OCD is not fully understood and degenerative joint disease may develop over time.2
The patient in this case is presenting with advanced OCD, which is indicated by radiographic changes and the presence of loose bodies in the elbow joint. Early, stable lesions can be managed by rest but unstable OCD lesions with loose bodies generally require surgery.2 Arthroscopic or open excision of the loose bodies must be performed to prevent mechanical symptoms and recurrent effusions.1,2
Depending on the size and stability of the lesion, fixation of unstable lesions or osteochondral fragment removal can be performed. In general, fragments consisting of 50% or more of the capitellum require fixation. Osteochondral autograft plugs are used for large defects to restore the articular surface.1,2
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor in chief of the Journal of Orthopedics for Physician Assistants.
1. Baker CL III, Romeo AA, Baker CL Jr. Osteochondritis dissecans of the capitellum. Am J Sports Med. 2010;38(9):1917-1928. doi:10.1177/0363546509354969
2. Ruchelsman DE, Hall MP, Youm T. Osteochondritis dissecans of the capitellum: current concepts. J Am Acad Orthop Surg. 2010;18(9):557-567. doi:10.5435/00124635-201009000-0000