J Korean Med Sci.  2003 Feb;18(1):127-130. 10.3346/jkms.2003.18.1.127.

Extraskeletal Osteochondroma of the Buttock

• Lim SC
• Kim YS
• Kim YS
• Moon YR

• KMID: 1099809
• DOI: http://doi.org/10.3346/jkms.2003.18.1.127

Abstract

Osteochondromas are common and typically arise from the metaphyseal ends of long bones. An osteochondral neoplasm of the soft tissue, which is a lesion of uncertain pathogenesis, is uncommon and usually arises from the synovial tissue in joints and tendon sheaths. Rarely, extraskeletal osteochondromas also arise outside of synovial compartments. Most of the reported cases were presented in the hands and feet, especially in the fingers. Here we describe a 44-yr-old female patient who presented with a pain in the left buttock. A well-defined osseous mass was detected in the buttock. It consisted of sharply demarcated, mature hyaline cartilage that was covered with a fibrous capsule, which changed gradually into cancellous bone, more pronouncedly at the center. The diagnosis of an extraskeletal osteochondroma should be considered when a discrete, ossified mass is localized in the soft tissues. A case of pathologically proven extraskeletal osteochondroma of the buttock is presented with a literature review, magnetic resonance imaging, and radiological findings.

Keyword

Osteochondroma; Soft Tissue Neoplasms; Buttocks; Histology

MeSH Terms

Accidental Falls
Adult
Buttocks*
Diagnosis, Differential
Female
Human
Myositis Ossificans/diagnosis
Osteochondroma/complications
Osteochondroma/diagnosis*
Osteochondroma/radiography
Osteochondroma/surgery
Pain/etiology
Sarcoma/diagnosis
Soft Tissue Neoplasms/complications
Soft Tissue Neoplasms/diagnosis*
Soft Tissue Neoplasms/radiography
Soft Tissue Neoplasms/surgery