Osteochondroma at its rarest site
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Updated: Mar 19, 2026

Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma
Published on: April 12, 2019
Ankur Mittal1, Psb Srinivasulu1, R Ramprasd1
1Mittal Surgical Hospital, Ambala Road, Kaithal - 136027 Harayana.
Introduction:
Osteochondromas usually arise from the metaphyseal region of the growing skeleton but extraskeletal cartilaginous tumors are rarest.
Case Report:
A 65 year old woman presented with anterior knee pain and inability to flex her knee more than 90° since 1 year. Clinical examination and imaging studies revealed a nodular calcific mass in the anterior portion of the knee i.e. patella. Following excision, histopathology confirmed the diagnosis of extra-osseous osteochondroma-like soft tissue mass, with no recurrence in 36 weeks.
Conclusion:
An integrated clinical-pathologic diagnosis helps to clarify the nature of extraskeletal cartilaginous tumors that can arise at unusual anatomic site viz. patella. Complete local surgical excision is the management of choice.
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