Janina M. Patsch

Background/Objectives: To test whether routine T1-weighted spin-echo (T1-SE) and proton-density fast spin-echo (PD-FSE) MRI signal intensity (SI) can index bone regeneration after osteochondral scaffold implantation by correlating MRI metrics with micro-CT and histology. Methods: Twenty-eight sheep with bilateral trochlear defects were evaluated in separate cohorts at 30, 180, and 365 days (n = 7, 11, and 10, respectively). One knee received a tri-layered resorbable scaffold; the contralateral defect was left empty. MRI (T1-SE, PD-FSE) was read by two blinded musculoskeletal radiologists using 10-point Likert scales (T1: apparent mineralization; PD: SI normalization). Contrast-to-noise ratio (CNR) between repair-bone and reference bone was computed. MRI measures were correlated with micro-CT (new bone volume; trabecular bone volume) and histology (ICRS subchondral bone reconstruction; new bone; filling). Results: Likert ratings on both T1-SE and PD-FSE correlated with micro-CT new bone volume and trabecular bone volume and with histological measures of repair. PD-FSE CNR was inversely associated with micro-CT new bone volume and trabecular bone volume (both p < 0.001), indicating lower CNR with greater bone regeneration, whereas T1-SE CNR showed no significant associations. Inter-reader agreement was excellent (ICC 0.947 individual; 0.973 average), with good-to-excellent intra-reader reliability (0.920–0.963). Conclusions: Reader-based Likert assessment on both sequences and PD-FSE CNR provide complementary, non-invasive markers of subchondral bone regeneration, supporting MRI for radiation-free follow-up and endpoint selection in future translational studies. T1-SE CNR did not track incremental mineralization and should not be used as a stand-alone quantitative marker in early healing.

Background/Objectives: Injuries remain a major cause of childhood morbidity and mortality in Europe, despite improved prevention. Infants under one year are particularly vulnerable because of limited motor control and complete dependence on caregivers. Existing studies are often small or cover broad age ranges, limiting infant-specific insights. This study aims to provide a comprehensive overview of injury types, mechanisms, and treatments, focusing exclusively on infants aged zero to one year. Methods: This retrospective study analyzed 29,574 infants and children (<2 years) treated at a level 1 trauma department from 1993 to 2022. Primary data included main diagnosis, injury mechanism, and treatment. Injuries were classified by diagnosis and mechanism. Surgeries were categorized by procedure type. Results: Injury frequency increased with age. A total of 31.1% of cases occurred in infants (<12 months) and 68.9% in children (12–24 months). Head injuries were the most common trauma type (44%), particularly among infants (69.9%; children: 32.2%), while wounds (infants: 10.2%; children: 31.5%) and fractures (infants: 4.2%; children: 8.4%) were more frequent in children. Falls were the predominant mechanism (77.9%) across both groups. Most injuries were treated conservatively. A total of 228 surgical interventions were performed (0.8%), mainly for wounds (54.8%) and fractures (30.3%). Conclusions: This study shows that, even within the first two years of life, child development shapes both injury frequency and type. As mobility and independence increase, injuries rise, from predominantly head trauma among infants to a higher incidence of wounds and fractures in children. The majority of injuries were minor and managed conservatively.

Lateral facial clefts are rare and often part of more complex syndromic neurocristopathies. According to Tessier’s classification, they correspond to facial cleft numbers 6, 7 and 8. Using micro-computer tomography (micro-CT), we analyzed their underlying bone defects (resolution 50 and 55 µm/voxel) in the context of the known syndrome-specific genetic background. Lateral facial clefts were diagnosed in three severely affected museum specimens representing mandibulofacial dysostosis type Treacher Collins syndrome (TCS), acrofacial dysostosis syndrome of Rodriguez (AFD-Rod) and tetra-amelia syndrome (TETAMS). The TCS specimen mainly showed an absence of the zygomatic bones and most of the lateral maxilla. The AFD-Rod specimen showed an extensive defect of the lateral maxilla, zygomatic bones, and mandible. The TETAMS specimen showed almost isolated agnathia. Possible relationships are discussed between the diverse facial bone defects due to apoptosis of neural crest-derived cells, known to be associated with ribosomopathies and spliceosomopathies, such as TCS and AFD-Rod, and the more targeted bone defects due to genetic variants known to cause TETAMS.

Background/objectives: This study prospectively evaluated clinical outcomes and osseous consolidation in patients with symptomatic scaphoid non-union treated with avascular bone grafting and percutaneous screw fixation. Two imaging methods, MDCT (multi-detector computed tomography) and HR-pQCT (high-resolution peripheric quantitative computer tomography), were employed to assess bone healing. Methods: In Vienna, eight consecutive patients with nine symptomatic scaphoid non-unions underwent revision surgery. Clinical outcomes were measured using DASH and PRWE scores, grip strength, and thumb strength. MDCT and HR-pQCT imaging were conducted 6 and 12 weeks post-operatively. Results: The median DASH score improved significantly from 43.3 (range 3.3–76.7) pre-operatively to 26.6 (p = 0.024) at 3 months and 16.2 (p = 0.06) at 12 months post-operatively. At 5–6 years, the median DASH score was 2 (range 0–15). At 6 weeks, both MDCT and HR-pQCT detected >50% bone healing at the distal interface. At the proximal interface, HR-pQCT detected >50% healing in all cases, whereas MDCT still showed 50% osseous consolidation at both interfaces. Conclusions: Avascular iliac grafting with screw fixation achieved excellent long-term clinical outcomes for symptomatic scaphoid non-union. HR-pQCT proved superior to MDCT for assessing early bone healing.

A huge number of inbred mouse strains with different bone properties have become available for musculoskeletal research. C57Bl/6J and C3H/HeOuJ mice show a significant difference in their bone characteristics. Nevertheless, there is a lack of knowledge on the molecular basis of these strain differences. The aim of this study is to determine the gene expression of selected regulators expressed in the bone marrow as well as bone microstructure of C57Bl/6J and C3H/HeOuJ mice. Bone properties were investigated in 20-week-old female C57Bl/6J and C3H/HeOuJ mice. Total RNA was extracted from the bone marrow of the tibia and gene expression of the following genes was determined by quantitative real-time PCR: SOST, DKK1, OPN, FGF23, RANKL, IL6, TNF, IL17a, and OPG. The femur and third lumbar vertebral body (L3) were investigated by μCT. Bone histomorphometric evaluations were performed in tartrate-resistant acid phosphatase/toluidine blue stained fourth lumbar vertebral bodies (L4). C57Bl/6J and C3H/HeOuJ mice showed significant differences in the gene expression of DKK1, FGF23, IL-6, TNF, and OPG. When compared with C57Bl/6J mice, C3H/HeOuJ mice had a stronger cortical and trabecular bone microstructure at the femur. In contrast, at L3 bone volume/total volume (BV/TV) and trabecular number were significantly higher in C57Bl/6J than in C3H/HeOuJ mice. Bone histomorphometry of L4 revealed significantly higher BV/TV, trabecular number, and thickness in C57Bl/6J mice. Furthermore, the number of osteoblasts and the number of osteoclasts/bone perimeter were higher in the C57Bl/6J mice. This study shows that C57Bl/6J and C3H/HeOuJ mice exhibit a differential expression of cytokines present in the bone marrow. Bone properties differ not only between both strains but also in relation to the investigated bone region.

Background: Liver transplantation is the state-of-the-art curative treatment for end-stage liver disease. Imaging is a key element in the detection of postoperative complications. So far, limited data is available regarding the best radiologic approach to monitor children after liver transplantation. Objective: To harmonize the imaging of pediatric liver transplantation, the European Society of Pediatric Radiology Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra-, and postoperative phases. This paper reports the responses related to postoperative imaging. Materials and methods: An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted, and 22 institutions from 11 countries returned the survey. Results: All sites commence ultrasound (US) monitoring within 24 h after liver transplantation. Monitoring frequency varies across sites, ranging from every 8 h to 72 h in early, and from daily to sporadic use in late postoperative phases. Predefined US protocols are used by 73% of sites. This commonly includes gray scale, color Doppler, and quantitative flow assessment. Alternative flow imaging techniques, contrast-enhanced US, and elastography are applied at 31.8%, 18.2%, and 63.6% of sites, respectively. Computed tomography is performed at 86.4% of sites when clarification is needed. Magnetic resonance imaging is used for selected cases at 36.4% of sites, mainly for assessment of biliary abnormalities or when blood tests are abnormal. Conclusion: Diagnostic imaging is extensively used for postoperative surveillance of children after liver transplantation. While US is generally prioritized, substantial differences were noted in US protocol, timing, and monitoring frequency. The study highlights potential areas for future optimization and standardization of imaging, essential for conducting multicenter studies.

Background: Liver transplantation is the state-of-the-art curative treatment for end-stage liver disease. Imaging is a key element in the detection of intraoperative and postoperative complications. So far, only limited data regarding the best radiological approach to monitor children during liver transplantation is available.Objective: To harmonize the imaging of pediatric liver transplantation, the European Society of Pediatric Radiology Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra- and postoperative phase. This paper reports the responses related to intraoperative imaging.Materials and methods: An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted, and 22 institutions from 11 countries returned the survey.Results: Intraoperative ultrasound (US) is used by all sites to assess the quality of the vascular anastomosis in order to ensure optimal perfusion of the liver transplant. Vessel depiction is commonly achieved using color Doppler (95.3%). Additional US-based techniques are employed by fewer centers (power angio mode, 28.6%; B-flow, 19%; contrast-enhanced US, 14.3%). Most centers prefer a collaborative approach, with surgeons responsible for probe handling, while radiologists operate the US machine (47.6%). Less commonly, the intraoperative US is performed by the surgeon alone (28.6%) or by the radiologist alone (23.8%). Timing of US, imaging frequency, and documentation practices vary among centers.Conclusion: Intraoperative US is consistently utilized across all sites during pediatric liver transplantation. However, considerable variations were observed in terms of the US setup, technique preferences, timing of controls, and documentation practices. These differences provide valuable insights for future optimization and harmonization studies.

Background: Liver transplantation is the state-of-the-art curative treatment in end-stage liver disease. Imaging is a key element for successful organ-transplantation to assist surgical planning. So far, only limited data regarding the best radiological approach to prepare children for liver transplantation is available. Objectives: In an attempt to harmonize imaging surrounding pediatric liver transplantation, the European Society of Pediatric Radiology (ESPR) Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra-, and postoperative phase. This paper reports the responses on preoperative imaging. Material and methods: An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted and 22 institutions from 11 countries returned the survey. From 2018 to 2020, the participating centers collectively conducted 1,524 transplantations, with a median of 20 transplantations per center per annum (range, 8–60). Results: Most sites (64%) consider ultrasound their preferred modality to define anatomy and to plan surgery in children before liver transplantation, and additional cross-sectional imaging is only used to answer specific questions (computed tomography [CT], 90.9%; magnetic resonance imaging [MRI], 54.5%). One-third of centers (31.8%) rely primarily on CT for pre-transplant evaluation. Imaging protocols differed substantially regarding applied CT scan ranges, number of contrast phases (range 1–4 phases), and applied MRI techniques. Conclusion: Diagnostic imaging is generally used in the work-up of children before liver transplantation. Substantial differences were noted regarding choice of modalities and protocols. We have identified starting points for future optimization and harmonization of the imaging approach to multicenter studies.