Most young patients with wrist arthritis will present with a history of trauma as their inciting event. Common causes of wrist arthritis in young patients are intercalated segment pathologies such as scapholunate advanced collapse and scaphoid nonunion advanced collapse, postdistal radius fracture arthritis, and pisotriquetral arthritis. Less common causes of wrist arthritis in young patient are nontraumatic in nature and encompass a wide range of etiologies that are idiopathic (eg, Kienbock and Preiser disease), congenital (Madelung deformity), metabolic (chondrocalcinosis), and inflammatory (juvenile idiopathic arthritis). A systematic approach to the patient visit is critical to arrive at the appropriate diagnosis.

Polymyalgia rheumatica is an inflammatory condition that affects persons older than 50 years of age and is characterized by pain in both shoulders with or without hip or neck pain (or both) and with pronounced morning stiffness. The condition is typically diagnosed on the basis of these hallmark symptoms along with elevated inflammation markers (erythrocyte sedimentation rate and C-reactive protein level) and the ruling out of other conditions including giant-cell arteritis. Glucocorticoids are the primary treatment, which provide rapid symptom relief. The initial dose, usually 12.5 to 25 mg of prednisone equivalent daily, is gradually reduced, ideally over 12 months or less, although the disease course varies and polymyalgia rheumatica may persist for a longer duration. Relapses are common and sometimes warrant the use of interleukin-6 receptor inhibitors or methotrexate to minimize glucocorticoid exposure.

With the establishment of key principles governing osteochondral structure, function, and reconstruction, researchers have gained an expanded toolkit for the precisein-vitroreconstruction of osteochondral tissues. As a convergence of tissue engineering and microphysiological modeling, the biomechanical heterogeneity of the osteochondral layers, which is critical to joint function, can be precisely engineered within osteochondral unit-on-a-chip (OC-OoCs), making them ideal tools for studying physiological activities. Specifically speaking, OC-OoCs are regarded as a promising platform for investigating the complex physiology of the osteochondral unit and its pathophysiology in disorders such as osteoarthritis (OA) and osteochondritis dissecans (OCDs). In OA, multiple forms of endochondral ossification, including chondrocalcinosis and osteophyte formation, disrupt the normal tissue relationship of cartilage, subchondral bone plate, and subchondral trabecular bone. Additionally, cellular and molecular communication networks between cartilage and subchondral bone are altered due to increased vascularization, porosity, microcracks, and fissures. Recapitulating these key physiological factors is therefore a critical objective in OC-OoC design. However, incorporation of increasing numbers of physiological parameters inevitably elevates system complexity, posing challenges to chip-to-chip reproducibility and batch-to-batch consistency. Robust quality control (QC) and standardization are thus essential to enhance the reliability and translational value of OC-OoC-derived data. This review summarizes the current advancements in OC-OoCs technology for osteochondral research and, from both diseases oriented as well as translational and clinical perspectives, highlights OC-OoCs' potential to advance our understanding of OA and facilitate the development of novel therapeutic strategies.

Background and Objectives: Knee osteoarthritis (OA) is a leading cause of pain and disability, with radiographic severity influenced by age, biomechanical alignment, and structural joint features. Data describing the association between common radiographic parameters and OA severity in Eastern European clinical populations remain limited. This study aimed to evaluate the associations between radiographic OA severity and coronal alignment, patellar height, and chondrocalcinosis in a Romanian clinical cohort. Materials and Methods: This single-center cross-sectional study included adult patients undergoing knee radiography for knee-related symptoms and/or functional assessment at a rehabilitation hospital between 2023 and 2025. Radiographs were obtained in the supine, non-weight-bearing position and included anteroposterior and lateral views. OA severity was graded using the Kellgren-Lawrence (KL) classification. Coronal alignment was assessed using the femorotibial angle, patellar height using the Insall-Salvati ratio (ISR), and chondrocalcinosis was recorded as present or absent. Associations between radiographic parameters and KL grade were analyzed using non-parametric statistics. Receiver operating characteristic (ROC) analyses were performed for exploratory assessment of limited separation between distributions. Results: Moderate to severe OA (KL ≥ 3) was present in 49% of patients. KL grade showed a moderate positive correlation with age (r = 0.50, p < 0.001) and differed significantly across coronal alignment categories (p < 0.001). Varus/valgus and pathological alignment classifications demonstrated moderate sensitivity (0.69-0.85) and variable specificity (0.52-0.85) for higher KL grades. ROC analyses of continuous alignment and ISR measures yielded area under the curve values ranging from approximately 0.65 to 0.68, indicating limited separation between distributions. Radiographically detected chondrocalcinosis was present in 5.3% of patients and showed no significant association with OA severity, and neither did patellar height. Conclusions: In this single-center Romanian clinical cohort, radiographic OA severity was associated with coronal plane alignment but not with patellar height or chondrocalcinosis. Alignment measures demonstrated limited discriminative ability and should be interpreted as complementary rather than diagnostic indicators of OA severity. These findings provide descriptive radiographic data from an Eastern European clinical population and highlight the need for longitudinal and population-based studies incorporating mechanical axis assessment and functional outcomes.