Argininemia or arginase-1 deficiency constitutes a rare, genetic, metabolic disorder caused by mutations in arginase 1—the last enzyme of the urea cycle—that hydrolyses L-arginine to ornithine and urea. The disease is associated with progressive development of spasticity and other symptoms, including seizures, developmental delay, cognitive impairment, and hepatic pathology. The present review attempts to summarize the current knowledge on the pathophysiology of the disease and highlight novel methods for its evaluation. Different factors, such as the accumulation of arginine, ammonia, and guanidino compounds, act as neurotoxins and may account for the neurological sequelae observed in the disease. New markers, such as arginine/ornithine ratio along with metabolomics, machine learning algorithms, and genetic methods, can be useful in the early diagnosis of argininemia, while mobile phone apps can assist argininemic patients in adhering to the strict diet required. Neurophysiology, multi-modal imaging, and new modelling methods, such as induced pluripotent stem cells, hold promise for providing new insights into the pathophysiology of the disease. There are still many uncertainties regarding the underlying mechanisms of argininemia, but the use of novel modelling methods and new technology can lead to the decipherment of its pathophysiology, improvement of diagnostic accuracy, and better disease management.

Developmental dysplasia of the hip (DDH) remains a leading cause of early hip osteoarthritis and poses considerable technical challenges during total hip arthroplasty. Existing classification systems focus on the abnormal relationship between the femoral head and the acetabulum without emphasising the femoral morphological variations, which are equally significant in surgical planning. Dysplastic femora often demonstrate excessive neck anteversion, variable neck–shaft angles, reduced offset, and metaphyseal–diaphyseal mismatch with narrow intramedullary canals. These anatomical variations often compromise the abductor mechanism and alter hip biomechanics. Thorough preoperative planning is crucial and should include the evaluation of leg-length discrepancy, reconstruction of the hip centre of rotation, assessment of femoral version and canal morphology, implant selection, and consideration of femoral shortening osteotomy. Computed tomography-based planning can enhance preoperative planning in complex cases. Both cemented and cementless stems align with positive findings in DDH patients. Cemented stems enable reliable version control, decrease intraoperative fracture risk, and may be beneficial for patients with poor bone quality. In mild cases, most uncemented stems are suitable. More severe deformities necessitate specialised implant designs with conical fluted stems, which provide strong fixation and excellent long-term survivorship. Modular and custom-made options also achieve favourable outcomes in high-grade deformities. Femoral shortening osteotomies are often needed to restore biomechanics, correct abnormal version, and prevent nerve injury during reduction. The subtrochanteric osteotomy has been linked with excellent results in treating severe DDH. High-quality research is essential to deepen our understanding of proximal femur morphological abnormalities and to enhance surgical results.

Congenital malformations constitute a major public health issue. Nonetheless, Greece does not participate in the European network of congenital anomalies. To examine the epidemiology of congenital abnormalities and investigate possible factors associated with their development, autopsies were performed on 649 fetuses referred from three healthcare facilities in Thessaloniki during 1992–2008. Adequate statistical analysis methods were implemented. Birth defects were found in 256 fetuses (39.5%)—primarily related to the musculoskeletal (17.3%), nervous (14.5%), cardiovascular (12.5%) and urinary (10.4%) systems. A statistically significant positive correlation (p-values < 0.05) emerged between the presence of a congenital defect and intrauterine growth restriction, inability to identify the fetus’ sex, iatrogenic abortion, nuchal oedema and a single umbilical artery. An inverse association (p-values < 0.05) was deduced with the gestational age, twin pregnancy, stillbirth, chorioamnionitis, infarction and intervillous thrombus of the placenta and nuchal cord. In multivariable analysis, the relationship remained significant (p-values < 0.05) between the development of birth defects and iatrogenic abortion, nuchal oedema, presence of a single umbilical artery, chorioamnionitis, infarction of the placenta and nuchal cord. ROC curve analysis indicated area under the curve = 0.800, 95% confidence interval = 0.76–0.84, p-value = 0.000. Our study revealed the epidemiology of congenital anomalies in Greece, confirming the relationship between various factors and birth defect occurrence.