Influence of COVID-19 pandemic on hospitalisations at a paediatric traumatology department during 2020: a single-centre observational study and comprehensive literature review.

PURPOSE: The study investigates changes in the injury characteristics of hospitalised children in a paediatric trauma centre during the COVID-19 pandemic. METHODS: Data from injured children from the pre-pandemic year 2019 were compared to the pandemic year 2020 using Pearson's chi-squared test and the Mann-Whitney U test. The period of highly restrictive regulations (HRP) was evaluated separately. A comprehensive literature review with defined search terms resulted in a descriptive data synthesis. RESULTS: Data from 865 patients indicated reductions in admissions of 5.6% and 54.4% during the HRP. In 2020, the hospitalisation time was longer (2.2 ± 2.7 days in 2019 vs. 2.4 ± 2.6 in 2020, p = 0.045); the proportions of wounds requiring surgical therapy (p = 0.008) and of observational treatments, primarily for mild brain injuries (p = 0.046), were higher; and conservative treatments, primarily for contusions, were lower (p = 0.005). There were no significant changes in age, location of lesions, or frequency of surgical therapy; nor were there differences in the HRP, except for fewer injuries in school and kindergarten (p < 0.001). The literature review summarises the main results of 79 studies. CONCLUSION: Limited resources did not alter the indications for surgical therapy. Further studies should examine whether the more common injuries sustained at home were caused by excessive work/childcare demands on parents. Reduced inpatient conservative treatment implies that hospital resources possibly were overused previously. The literature offers answers to many detailed questions regarding childhood injuries during a pandemic and more efficient safe treatment. Registration Ethical committee of RWTH Aachen University EK 22-320; Center for Translational & Clinical Research RWTH Aachen University (CTC-A) 21-430.

Variant of the catalytic cysteine of UFSP2 leads to spondyloepimetaphyseal dysplasia type Di Rocco.

Spondyloepimetaphyseal dysplasia (SEMD) is characterized by vertebral, epiphyseal, and metaphyseal alterations. Patients become predominantly apparent with disproportionate short stature. The genetic background of SEMD is heterogeneous, with different modes of inheritance (autosomal dominant, autosomal recessive, and X-linked disorders). Amongst the genes in which variants are known to cause SEMD, UFM1-specific protease 2 (UFSP2) encodes a cysteine protease involved in the maturation of Ubiquitin-fold modifier 1 (UFM1). Heterozygous pathogenic variants affecting the C-terminal catalytic domain of UFSP2 are related to two entities of skeletal dysplasia, Beukes hip dysplasia (BHD) and SEMD type Di Rocco (SEMDDR). This is the first report of a de novo heterozygous variant affecting the catalytic Cys302 residue of UFSP2 (NM_018359.3:c.905G>C, p.(Cys302Ser)) causing SEMDDR. According to previously described patients with SEMDDR, our patient presented with disproportionate short stature, genu varum, gait instability, and radiologically detected epiphyseal and metaphyseal alterations. Additionally, a bell-shaped thorax, lumbar hyperlordosis, muscular hypotonia, and coxa vara were observed in the patient described in this study. Our findings underline the fundamental importance of an intact catalytic triad of the human UFSP2 for normal skeletal development and extend the phenotypical features of patients with UFSP2-related skeletal dysplasia.

Stabilisation of Pathologic Proximal Femoral Fracture near the Growth Plate with Use of a Locking Plate and Transphyseal Screws.

Aneurysmal bone cyst (ABC) is a benign osseus lesion with a high pathologic fracture risk. The described treatment options are varied and inconsistent. For successful treatment results, it is essential to prevent recurrence and sufficiently stabilise the weakened bone. Lesions close to the growth plates, especially in the femoral neck region, are challenging to stabilise in children. In this study, 27 clinics, including 11 sarcoma centres, 15 paediatric orthopaedic clinics, and one sarcoma/paediatric orthopaedic centre, were surveyed and asked about their treatment approaches for an exemplary case of ABC in the femoral neck causing a pathological fracture in a 20-month-old infant, with a response rate of 81%. The heterogeneity of treatment options described in the literature is consistent with the survey results. The most favoured approach was curettage, defect filling of any kind, and surgical stabilisation. However, the lesion stabilisation option introduced in this paper, which involves the use of transphyseal screws, was not mentioned in the survey and has not been reported in the literature. Contrary to the existing concepts, our technique offers high stability without significant growth restriction. Transphyseal screws are also suitable for the treatment of femoral neck fractures of other aetiologies in children.

3D accuracy and clinical outcomes of corrective osteotomies with patient-specific instruments in complex upper extremity deformities: an approach for investigation and correlation.

BACKGROUND: Corrective osteotomies of the upper extremities with patient-specific instruments (PSIs) are increasingly used. In this context, the concordance between planning and postoperative 3D radiographs as well as the association between 3D accuracy and clinical outcome has rarely been evaluated. In this pilot study, we aimed to investigate our clinical mid-term outcome and 3D accuracy as well as their possible correlation, including identifying aspects critical to reaching optimal correction results. METHODS: From October 2018 to January 2020, we used PSIs for 12 corrective osteotomies of the upper extremity in 11 bones of 8 patients (congenital or posttraumatic deformities in 2 elbows, 3 forearms, 3 distal radii). In follow-up examination (10-25 months postoperatively), patient satisfaction, grip strength, ROM, VAS, and DASH were evaluated. Three-dimensional radiological accuracy was determined with 3D-reconstructed postoperative CT scans. With the software tool "Part Comparison" of Mimics® Innovation Suite Software/Materialise, surface differences of pre-planned and postoperative 3D models were compared. RESULTS: Compared to the preoperative situation pain and function were better at follow-up: The average VAS score significantly decreased from 6.5 ± 4.1 cm preoperatively to 2.3 ± 2.6 cm at the follow-up time point (p = 0.008). The average DASH score significantly improved, from 48.4 ± 30.9 to 27.0 ± 25.2 (p = 0.015). In the part comparison analysis "planned vs postoperative comparison", significantly more points in percent (= 3D accuracy) were in a -3 mm to 3 mm interval than in the "preoperative vs planned comparison" (87.3 ± 13.8% vs 48.9 ± 16.6%, p = 0.004). After surgery, the maximum deviation value over all cases was 4.5 ± 1.1 mm, and the minimum deviation value was - 4.5 ± 1.2 mm vs preoperatively 12.9 ± 6.2 mm (p = 0.004) and - 7.2 ± 2.1 mm (p = 0.02), respectively. Clinically, in all cases with higher accuracy (> 90%), an improvement of either DASH or VAS or both of > 60% to the preoperative values occurred. There was a significant correlation between accuracy (%) and ΔVAS (p = 0.004). There were no method-related complications. CONCLUSIONS: Our data after PSI-based corrective osteotomy in complex deformities of the upper extremity in a limited number of cases indicate a positive correlation between 3D accuracy and clinical outcomes. Examination of 3D accuracy to analyse sources of error in the hole procedure from initial CT scan to end of surgery even in patients with not fully satisfactory clinical results is required for further development of the method to achieve optimal correction results with nearly 100% congruence between the planned and postoperative 3D bone position. Trial registration This retrospective study was registered in the Center for Translational & Clinical Research Aachen (CTC-A) with the number 20-514 on November 20, 2021.

Clinical translation of a patient-specific scaffold-guided bone regeneration concept in four cases with large long bone defects.

Background: Bone defects after trauma, infection, or tumour resection present a challenge for patients and clinicians. To date, autologous bone graft (ABG) is the gold standard for bone regeneration. To address the limitations of ABG such as limited harvest volume as well as overly fast remodelling and resorption, a new treatment strategy of scaffold-guided bone regeneration (SGBR) was developed. In a well-characterized sheep model of large to extra-large tibial segmental defects, three-dimensional (3D) printed composite scaffolds have shown clinically relevant biocompatibility and osteoconductive capacity in SGBR strategies. Here, we report four challenging clinical cases with large complex posttraumatic long bone defects using patient-specific SGBR as a successful treatment. Methods: After giving informed consent computed tomography (CT) images were used to design patient-specific biodegradable medical-grade polycaprolactone-tricalcium phosphate (mPCL-TCP, 80:20 â€‹wt%) scaffolds. The CT scans were segmented using Materialise Mimics to produce a defect model and the scaffold parts were designed with Autodesk Meshmixer. Scaffold prototypes were 3D-printed to validate robust clinical handling and bone defect fit. The final scaffold design was additively manufactured under Food and Drug Administration (FDA) guidelines for patient-specific and custom-made implants by Osteopore International Pte Ltd. Results: Four patients (age: 23-42 years) with posttraumatic lower extremity large long bone defects (case 1: 4 â€‹cm distal femur, case 2: 10 â€‹cm tibia shaft, case 3: complex malunion femur, case 4: irregularly shaped defect distal tibia) are presented. After giving informed consent, the patients were treated surgically by implanting a custom-made mPCL-TCP scaffold loaded with ABG (case 2: additional application of recombinant human bone morphogenetic protein-2) harvested with the Reamer-Irrigator-Aspirator system (RIA, Synthes®). In all cases, the scaffolds matched the actual anatomical defect well and no perioperative adverse events were observed. Cases 1, 3 and 4 showed evidence of bony ingrowth into the large honeycomb pores (pores >2 â€‹mm) and fully interconnected scaffold architecture with indicative osseous bridges at the bony ends on the last radiographic follow-up (8-9 months after implantation). Comprehensive bone regeneration and full weight bearing were achieved in case 2 â€‹at follow-up 23 months after implantation. Conclusion: This study shows the bench to bedside translation of guided bone regeneration principles into scaffold-based bone tissue engineering. The scaffold design in SGBR should have a tissue-specific morphological signature which stimulates and directs the stages from the initial host response towards the full regeneration. Thereby, the scaffolds provide a physical niche with morphology and biomaterial properties that allow cell migration, proliferation, and formation of vascularized tissue in the first one to two months, followed by functional bone formation and the capacity for physiological bone remodelling. Great design flexibility of composite scaffolds to support the one to three-year bone regeneration was observed in four patients with complex long bone defects. The translational potential of this article: This study reports on the clinical efficacy of SGBR in the treatment of long bone defects. Moreover, it presents a comprehensive narrative of the rationale of this technology, highlighting its potential for bone regeneration treatment regimens in patients with any type of large and complex osseous defects.

Surgical Treatment of Bone Sarcoma.

Bone sarcomas are rare primary malignant mesenchymal bone tumors. The three main entities are osteosarcoma, chondrosarcoma, and Ewing sarcoma. While prognosis has improved for affected patients over the past decades, bone sarcomas are still critical conditions that require an interdisciplinary diagnostic and therapeutic approach. While radiotherapy plays a role especially in Ewing sarcoma and chemotherapy in Ewing sarcoma and osteosarcoma, surgery remains the main pillar of treatment in all three entities. After complete tumor resection, the created bone defects need to be reconstructed. Possible strategies are implantation of allografts or autografts including vascularized bone grafts (e.g., of the fibula). Around the knee joint, rotationplasty can be performed or, as an alternative, the implantation of (expandable) megaprostheses can be performed. Challenges still associated with the implantation of foreign materials are aseptic loosening and infection. Future improvements may come with advances in 3D printing of individualized resection blades/implants, thus also securing safe tumor resection margins while at the same time shortening the required surgical time. Faster osseointegration and lower infection rates may possibly be achieved through more elaborate implant surface structures.

Contrast-enhanced MRI predicts local recurrence of osteoid osteoma after radiofrequency ablation.

INTRODUCTION: Osteoid osteoma is a painful benign tumour, which is commonly treated by radiofrequency ablation (RFA). The goal of this study is to assess the value of contrast-enhanced magnetic resonance imaging (MRI) for predicting clinical success after RFA of osteoid osteoma. METHODS: Twenty consecutive patients (14 male, 6 female; mean age 23.3 ± 13.4 years) suffering from osteoid osteoma underwent unenhanced and contrast-enhanced T1-weighted MRI the day after RFA. Post-interventional contrast enhancement of the nidus was analyzed by comparing signal-to-noise ratios (SNR) of the nidus before and after contrast administration. The SNR between pre- and post-contrast scans was computed. RESULTS: There were no significant differences in SNR between pre- and post-contrast scans in the area of ablation (P = 0.1583), while the SNR exceeded one in four patients, indicating residual contrast enhancement. In three of these patients clinical symptoms recurred, requiring re-ablation, while one patient remained free from symptoms during follow-up. In patients with a pre- and post-contrast SNR of ≤ 1.18 no local recurrence was observed. CONCLUSIONS: Contrast enhancement on T1-weighted MRI imaging seems to be predictive of clinically unsuccessful RFA in osteoid osteoma. Patients with a SNR increase of ≥ 20% after contrast administration might be considered for re-ablation to avoid symptomatic tumour recurrence.

Radiofrequency ablation of osteoid osteoma: initial experience with a new monopolar ablation device.

The purpose of this article is to report our initial experience with the "off-label" use of a new monopolar radiofrequency (RF) probe for percutaneous ablation of osteoid osteomas. Seventeen patients (12 male and 5 female, mean age 24.8 [range 9-49]) with osteoid osteoma were treated by computed tomography (CT)-guided RF ablation (RFA). All procedures were performed with the patient under general aesthesia. After localization of the nidus, a 13G hollow drill was introduced into the nidus through a 7F introducer sheath. A monopolar 16.5G RF probe with a 9-mm active tip (Soloist; Boston Scientific, Natick, MA) was inserted through the introducer sheath and connected to the RF generator. Energy application was started at 2 W and subsequently increased every 2 min by 1 W to a maximum of 8 W. The procedure ended if impedance increased by 500 Ω. Mean duration of energy deposition was 14.2±3.3 min. Fourteen of 17 patients (82%) were free of symptoms at 29.9±14.8 (range 4 to 47) months of follow-up. The primary and secondary success rates were 83% and 100%, respectively. In 3 patients, recurrence of pain at 6 (n=1) and 15 (n=2) months after the initial procedure was successfully treated by reablation. There were no complications. Monopolar RFA using the Soloist probe is effective and safe for the treatment of osteoid osteoma. It results in comparable success rates as other monopolar or bipolar RF systems in the treatment of osteoid osteoma.