Comprehensive analysis of pathological changes in hip joint capsule of patients with developmental dysplasia of the hip

Aims: Developmental dysplasia of the hip (DDH) is a complex musculoskeletal disease that occurs mostly in children. This study aimed to investigate the molecular changes in the hip joint capsule of patients with DDH. Results: More than one thousand genes were differentially expressed in hip joint capsules between healthy controls and DDH. Both gene ontology (GO) and Kyoto encyclopedia of genes and genome (KEGG) analyses revealed that extracellular matrix (ECM) modifications, muscle system processes, and cell proliferation were markedly influenced by the differentially expressed genes. Conclusion: DDH is associated with the loss of collagen fibers and fibroblasts, which may cause loose joint capsule formation. However, the degree of differentiation of fibroblasts to myofibroblasts needs further studies. Overall design: Methods: High-throughput sequencing was used to identify genes that were differentially expressed in hip joint capsules between healthy controls and DDH patients. Patients with DDH (n=6) and control subjects (n=6) were enrolled in this study. The diagnosis of the patients with DDH was confirmed by expert medical examination with nuclear magnetic resonance and radiographic evidence, and they all had unilateral or bilateral DDH. Control subjects are enrolled from patients with femoral neck fracture due to falling accidence.