Bone is a mineralized and elastic connective tissue that provides fundamental functions in the human body, including mechanical support to the muscles and joints, protection of vital organs and storage of minerals. Bone is a metabolically active organ that undergoes continuous remodeling processes to maintain its architecture, shape, and function throughout life. One of the most important medical discoveries of recent decades has been that the immune system is involved in bone remodeling. Indeed, chronic inflammation has been recognized as the most significant factor influencing bone homeostasis, causing a shift in the bone remodeling process toward pathological bone resorption. Bone osteolytic diseases typified by excessive bone resorption account for one of the greatest causes of disability worldwide, with significant economic and public health burdens. From this perspective, we discuss the recent findings and discoveries highlighting the cellular and molecular mechanisms that regulate this process in the bone microenvironment, in addition to the current therapeutic strategies for the treatment of osteolytic bone diseases.

Intervertebral disc degeneration (IVDD) is a pathological condition that can lead to intractable back pain or secondary neurological deficits. There is no fundamental cure for this condition, and current treatments focus on alleviating symptoms indirectly. Numerous studies have been performed to date, and the major strategy for all treatments of IVDD is to prevent cell loss due to programmed or regulated cell death. Accumulating evidence suggests that several types of cell death other than apoptosis, including necroptosis, pyroptosis, and ferroptosis, are also involved in IVDD. In this study, we discuss the molecular pathway of each type of cell death and review the literature that has identified their role in IVDD. We also summarize the recent advances in targeted therapy at the RNA level, including RNA modulations through RNA interference and regulation of non-coding RNAs, for preventing cell death and subsequent IVDD. Therefore, we review the causes and possible therapeutic targets for RNA intervention and discuss the future direction of this research field.

Ions of capitellar osteochondritis dissecans....

Background: Autologous osteochondral mosaicplasty is a new technique to provide hyaline repair for articular defects. Although recent studies have reported the successful treatment of articular defects in the knee and ankle joints with this surgical procedure, little attention has been given to the surgical efficacy of mosaicplasty in the treatment of osteochondritis dissecans of the humeral capitellum. Purpose: To clarify the clinical outcomes of mosaicplasty for teenaged patients with advanced lesions of capitellar osteochondritis dissecans. Study Design: Case series; Level of evidence, 4. Methods: Eight teenaged patients with advanced lesions of capitellar osteochondritis dissecans underwent mosaicplasties. All patients were baseball players who were affected on the right side, which was also their throwing side. The surgical technique involves obtaining small-sized cylindrical osteochondral grafts from the lateral periphery of the femoral condyles and transplanting them to prepared osteochondral defects. At a mean follow-up of 24 months, all patients were evaluated clinically and radiographically. Results: Seven of the 8 patients were free from elbow pain, and the remaining patient had mild pain occasionally. The mean clinical score described by Timmerman and Andrews (a maximum of 200 points) significantly improved from 140 points to 183 points postoperatively. All patients except one had excellent or good clinical results. Radiographically, the graft incorporation and a normal contour of the subchondral cortex were found in all patients. Magnetic resonance imaging showed that the preoperative heterogeneity of the lesion had disappeared and the signal intensity returned to normal. Six of the 8 patients, including all 3 pitchers, returned to competitive-level baseball. Conclusion: Mosaicplasty for advanced lesions of capitellar osteochondritis dissecans in teenaged baseball players can provide satisfactory clinical and radiographic results.