Osteoradionecrosis of the Hip, a Troublesome Complication of Radiation Therapy: Case Series and Systematic Review.

Background: Osteoradionecrosis of the hip is a serious complication of radiotherapy that is easily overlooked by physicians and patients in the early stages. There are relatively few reports on this subject, so there is no clear scientific consensus for the pathogenesis, early diagnosis, and clinical treatment of hip osteoradionecrosis. In this paper, we report two cases of hip osteoradionecrosis and systematically review the related literature. Case Presentation: We report two cases of hip osteoradionecrosis. One patient successfully underwent total hip arthroplasty in our hospital and recovered well postoperatively. Another patient although we offered a variety of surgical options for this patient, the patient was worried that the bone loss would lead to poor prosthesis fixation, resulting in prosthesis loosening and infection, and therefore ultimately refused surgical treatment. Conclusion: With the development of radiological techniques, the incidence of hip osteoradionecrosis is decreasing year by year, but early diagnosis and rational treatment remain challenging. The effects of non-surgical treatment are limited. Early prevention, early detection, and early intervention are crucial to delay or prevent the emergence of more serious complications.

The development of satellite cells and their niche in striated muscle complex of anorectal malformations rat embryos.

BACKGROUND: It has been demonstrated that different degrees of pelvic floor muscle (PFM) maldevelop in anorectal malformations (ARMs); yet the development of satellite cells, the myogenic stem cells responsible for muscle growth, repair, and maintenance remains elusive during the embryogenesis of PFM. Striated muscle complex (SMC) is one of the most important components of PFM. The objective of this study was to observe the development pattern of satellite cells and their niche of SMC and investigate its possible role in PFM dysplasia in ARMs. METHODS: Immunohistochemistry, cell culture, transmission electron microscopy (TEM), real-time quantitative PCR, and Western blot were performed to trace the dynamic development pattern of satellite cells during the morphogenesis of PFM in ethylenethiourea (ETU)-induced ARMs rat embryos. RESULTS: In ARMs rat embryos, earlier presentation and higher number of Pax7-expressing cell were observed in SMC. The expression of Pax7 and vimentin were up-regulated, while the expression of myogenin, vWF, and neurofilament were down-regulated. Ultrastructure analysis of SMC was characterized by increased amount of nuclear heterochromatin of satellite cell nuclei, thickened basal lamina, widened gap between satellite cell and myofiber, and disarrangement of muscle fibers. The satellite cells demonstrated abnormal differentiation after they were isolated and cultured in vitro. CONCLUSIONS: Our results suggest that premature origination of satellite cell from myogenic progenitor or precursor may result in the depletion of myogenic precursor and cessation of muscle growth; intrinsic defect in satellite cell structure, and extrinsic impairment of microenvironment compromised the myogenic competence of satellite cell, which might contribute substantially to the hypoplastic SMC in ARMs.