Identical Twins with Legg-Calve-Perthes Disease: A Report of Two Cases
Year: 2026
Type: article
Abstract: Introduction: Legg-Calvé-Perthes disease (LCPD) is an idiopathic avascular necrosis of the femoral head in children, with proposed etiologies, including genetic mutations and coagulation abnormalities. While familial clustering has been reported, the role of genetic predisposition remains incompletely understood, particularly in monozygotic twins. Case Report: We report monozygotic male twins born at 35 weeks' gestation who developed LCPD sequentially. Twin A presented at 3 years and 4 months with a 2-week history of antalgic gait. Initial imaging was unremarkable, but follow-up radiographs demonstrated progressive changes consistent with LCPD, ultimately classified as lateral pillar Class A. He was managed conservatively with observation and showed clinical and radiographic improvement at 1 year. During Twin A's 1-year follow-up, Twin B presented with similar symptoms of antalgic gait and mild right hip pain. Imaging revealed early fragmentation and mild lateral pillar height loss, consistent with early-stage LCPD. Given the favorable course in Twin A, Twin B was also managed non-operatively. Discussion: This case highlights the occurrence of LCPD in monozygotic twins raised in a shared environment, supporting a potential genetic contribution to disease pathogenesis. Prior studies have implicated hereditary thrombophilia and mutations in type II collagen in LCPD development. Although larger twin studies suggest low concordance rates, limited sample sizes restrict definitive conclusions. This case adds to existing reports suggesting a possible genetic predisposition, while also acknowledging the influence of shared environmental factors. Conclusion: The sequential development of LCPD in identical twins underscores the importance of considering genetic susceptibility in disease etiology. Increased clinical vigilance and early evaluation in siblings may facilitate timely diagnosis. Further research is needed to better define the genetic mechanisms contributing to LCPD.
Institution: Saint Louis University
Language: English
Topic: Bone and Joint Diseases
Subfield: Orthopedics and Sports Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $250
OpenAlex ID: W7225567784