Case Report

Chondrosarcoma arising from long-standing Dysplasia Epiphysealis Hemimelica of the proximal humerus: A case report

¹ First Department of Orthopaedic Surgery, School of Medicine, National and Kapodistrian University of Athens, Attikon University General Hospital, 1 Rimini Street, 12462 Chaidari, Athens, Greece
² Second Department of Radiology, School of Medicine, National and Kapodistrian University of Athens, Attikon University General Hospital, 1 Rimini Street, 12462 Chaidari, Athens, Greece
³ First Department of Pathology, School of Medicine, National and Kapodistrian University of Athens, 75 Mikras Asias Street, 115 27 Goudi, Athens, Greece

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it. ; This email address is being protected from spambots. You need JavaScript enabled to view it.

Received: 6 October 2025
Accepted: 19 October 2025

Abstract

Dysplasia Epiphysealis Hemimelica (DEH), or Trevor’s disease, is a rare, nonhereditary skeletal disorder involving abnormal cartilaginous overgrowth of the epiphysis. To our knowledge, malignant transformation has not been previously documented. We report a unique case of chondrosarcoma arising from a DEH lesion in the proximal humerus nearly 30 years after the initial diagnosis. The patient was treated with wide resection and reconstruction using a proximal humeral replacement with a reverse-constrained total shoulder arthroplasty. This case highlights the need for long-term follow-up in patients with DEH, especially when new symptoms suggest possible malignant transformation.