Reconstitution of the host holobiont in germ-free born male rats acutely increases bone growth and affects marrow cellular content

Integration of microbiota in a host begins at birth and progresses during adolescence, forming a multidirectional system of physiologic interactions. Here, we present an instantaneous effect of natural, bacterial gut colonization on the acceleration of longitudinal and radial bone growth in germ-free born, 7-week-old male rats. Changes in bone mass and structure were analyzed after 10 days following the onset of colonization through cohousing with conventional rats and revealed unprecedented acceleration of bone accrual in cortical and trabecular compartments, increased bone tissue mineral density, improved proliferation and hypertrophy of growth plate chondrocytes, bone lengthening, and preferential deposition of periosteal bone in the tibia diaphysis. In addition, the number of small in size adipocytes increased, while the number of megakaryocytes decreased, in the bone marrow of conventionalized germ-free rats indicating that not only bone mass but also bone marrow environment is under control of gut microbiota signaling. The changes in bone status paralleled with a positive shift in microbiota composition toward short chain fatty acids (SCFA)-producing microbes and a considerable increase in cecal SCFA concentrations, specifically butyrate. Further, reconstitution of the host holobiont increased hepatic expression of IGF-1 and its circulating levels. Elevated serum levels of 25-hydroxy vitamin D and alkaline phosphatase pointed toward an active process of bone formation. The acute stimulatory effect on bone growth occurred independently of body mass increase. Overall, the presented model of conventionalized germ-free rats could be used to study microbiota-based therapeutics for combatting dysbiosis-related bone disorders.

Management of diabetic foot ulcer & atherosclerosis using tibial transverse bone lengthening technique; Bangladesh experience

Diabetic foot ulcers (DFU) are chronic skin ulcers associated with deep tissue destruction around the foot and ankle region with varying degrees of lower extremity vasculopathy and neuropathy. Diabetic foot ulcer is associated with a high rate of morbidity, disability, mortality and psycho-social cost.

Elongated Styloid Process in Panoramic Radiographs

The aim of this study is to evaluate the prevalence of the elongated styloid process in panoramic radiographic exams, in a subpopulation of northern Brazil in relation to age, sex and side. Panoramic radiographs were selected, and the apparent size of the styloid process was measured from the point where the styloid leaves the tympanic plate to the tip of the process. The data were analyzed using chi-square tests and variance analysis with a 5% significance level. Approximately 30% of the elongated styloid process was observed in patients between 18 to 35 years. Of the styloid processes that measured more than 30 mm (elongated), 764 styloid processes (81%) showed Type I elongation pattern, 97 styloid processes (10%) showed Type II calcification patterns, and 85 styloid processes (9%) showed Type III calcification patterns. The prevalence of the elongated styloid process was high, and no statistically significant correlation was found between the presence of the elongated styloid process and the variables studied.Keywords: Bone Lengthening. Osteogenesis. Radiography, Panoramic. ResumoO objetivo deste estudo é avaliar a prevalência do processo estilóide alongado em exames radiográficos panorâmicos, em uma subpopulação do norte do Brasil em relação à idade, sexo e lado. Radiografias panorâmicas foram selecionadas, e tamanho aparente do processo estilóide foi medido a partir do ponto em que o estilóide deixa a placa timpânica até a ponta do processo. Os dados foram analisados por meio de testes qui-quadrado e análise de variância com nível de significância de 5%. Aproximadamente 73% do processo estilóide alongado foi observado em pacientes entre 18 e 53 anos (p <0,05). Dos processos estilóides que mediram mais de 30 mm (alongados), 543 processos estiloide (82,9%) mostraram padrão de alongamento do Tipo I, 33 processos estiloide (5,03%) mostraram padrões de calcificação do Tipo II, e 79 processos estilóide (12,06%) mostraram padrões de calcificação do Tipo III. A prevalência do processo estilóide alongado foi alta e não foi encontrada correlação estatisticamente significante entre a presença do processo estilóide alongado e as variáveis estudadas.Palavras-chave: Alongamento Ósseo. Osteogênese. Radiografia Panorâmica.

METABOLIC AND ORTHOPEDIC ASPECT OF X-LINKED VITAMIN D-RESISTANT HYPOPHOSPHATEMIC RICKETS

INTRODUCTION: - The X-linked vitamin D-resistant hypophosphatemic rickets (VDXLR) is a metabolic disorder. Medication treatment consists of oral phosphate substitution and supplementation of active vitamin D compounds. Our study aimed to review our patients with VDXLR, focusing on those undergoing surgery, mainly lengthening procedures. The main parameters of interest were growth, height, the axis of the lower limbs, pain, and degenerative arthropathy. METHODS: - Twelve patients with VDXLR were followed at our institution. Eight patients underwent surgical correction, and three of them in combination with bone lengthening. The corrections were executed at the end of growth in the patients. Clinical end points were height, leg axis, and pain. RESULTS: - Single bilateral surgical correction was performed in six patients; one patient had three and ve corrections. Bone lengthening was performed in three patients. At the last follow-up, the height of seven operated patients was within normal range. In addition, the leg axis was normalized in six patients with mild genua vara in two. Bone healing was excellent, and no surgical complications. There was no one radiological evidence of degenerative arthropathy. CONCLUSIONS: - In case of bone deformity, surgery can safely be performed, independent of age or bone maturation. All patients were happy with the outcomes of axial corrective surgery and bone lengthening, and in the majority. Only one corrective intervention was needed.

Lengthening of the ulna by callotasis in children with multiple hereditary exostoses: comparison of methods with and without internal fixation

Purpose The goal of this retrospective study was to compare the gradual lengthening of the ulna in children with multiple hereditary exostoses with and without an elastic intramedullary nail. Methods Between 1998 to 2018, the ulna was lengthened in 28 forearms in 21 patients (aged 7.1 to 16.6 years) using a monolateral external fixator when relative ulnar shortening exceeded 15 mm. In total, 16 forearms were lengthened with the external fixator (group I) and 12 forearms with the addition of an intramedullary elastic nail (group II). Subjective assessment of function, range of movement (ROM) of the wrist and elbow and complications were compared. Ulnar shortening, radial head dislocation, radial articular angle (RAA) and percentage of carpal slip and radial bowing were followed radiographically. The difference between the groups has been evaluated statistically. Results The function of the extremity improved partially in 81% of patients in group I and in 83% of patients in group II. ROM was not improved except for radial deviation. Radial head position did not change. The values in group II in comparison with group I are higher for gain of length and lower for bone lengthening index and for bone healing index. Carpal slip decreased insignificantly. The RAA and radial bowing decreased, the comparison of values between groups and age under and over ten years were not statistically significant. Complications were more common in group I. No permanent complications were noted. Conclusion The addition of an intramedullary nail during the gradual ulnar lengthening improves the gain, bone healing index and rate of complications. Level of Evidence III.

The discovery and clinical significance of Ilizarov’s second principle of biology (the “Harbin phenomenon” of bone transport)

The understanding of Ilizarov’s biological principles is guiding clinical treatment. Ilizarov’s First Principle of Biology, Distraction Histogenesis, is a fundamental guidance for bone lengthening. The “Harbin Phenomenon” is an extension of “Transformation Histogenesis”, which was discovered by bone transport for bone defects treatment. It describes the transformation and regeneration capacities of scar tissues under slow and rhythmic distraction, and this transformation satisfies the morphological and functional requirements. This principle is a supplement to the first principle, and could be Ilizarov’s Second Principle of Biology. Together they form the basis to guide clinical bone transport treatment.

Bone Lengthening with a Motorized Intramedullary Nail in 34 Patients with Posttraumatic Limb Length Discrepancies

The Fitbone® motorized nail system has been used to correct limb length discrepancies (LLD) for several years. This study focuses on its application in posttraumatic limb lengthening surgery, its outcome and challenges. Materials and methods: A prospective, single center study was conducted between 2010 and 2019 in patients treated with motorized lengthening nails. The inclusion criteria were symptomatic LLD of 20 mm or more. An imaging analysis was done using TraumaCad® software (Brainlab AG, Munich, Germany) to compare frontal alignment angles and limb length discrepancy (LLD) on preoperative and latest follow-up radiographs of the lower limbs. Results: Thirty-four patients were included with a mean age of 28.8 ± 9.7 years, a mean follow-up of 27.8 ± 13 months and a mean hospital stay of 4.4 ± 1.7 days. The mean LLD was 44 ± 18 mm in 29 femoral and 32 ± 8 mm in 4 tibial cases, which was reduced to less than 10 mm in 25/34 (74%) patients. The mean healing index was 84.6 ± 62.5 days/cm for femurs and 92 ± 38.6 days/cm for tibias. The mean time to resume full weight-bearing without walking aids was 226 days ± 133. There was no significant difference between preoperative and final follow-up alignment angles and range of motion. The mechanical lateral distal femoral angle (mLDFA) was corrected in the subgroup of 10 LLD patients with varus deformity of the femur (preoperative 95.7° (±5.0) vs. postoperative 91.5° (±3.4), p = 0.008). According to Paley’s classification, there were 14 problems, 10 obstacles and 2 complications. Discussion: Six instances of locking screw pull out, often requiring reoperation, raise the question of whether a more systematic use of blocking screws that provide greater stability might be indicated. Lack of compliance can lead to poor outcomes, patient selection in posttraumatic LLD patients is therefore important. Conclusion: Limb lengthening with a motorized lengthening nail for posttraumatic LLD is a relatively safe and reliable procedure. Full patient compliance is crucial. In-depth knowledge of lengthening and deformity correction techniques is essential to prevent and manage complications.

Systemic Administration of G-CSF Accelerates Bone Regeneration and Modulates Mobilization of Progenitor Cells in a Rat Model of Distraction Osteogenesis

Granulocyte colony-stimulating factor (G-CSF) was shown to promote bone regeneration and mobilization of vascular and osteogenic progenitor cells. In this study, we investigated the effects of a systemic low dose of G-CSF on both bone consolidation and mobilization of hematopoietic stem/progenitor cells (HSPCs), endothelial progenitor cells (EPCs) and mesenchymal stromal cells (MSCs) in a rat model of distraction osteogenesis (DO). Neovascularization and mineralization were longitudinally monitored using positron emission tomography and planar scintigraphy. Histological analysis was performed and the number of circulating HSPCs, EPCs and MSCs was studied by flow cytometry. Contrary to control group, in the early phase of consolidation, a bony bridge with lower osteoclast activity and a trend of an increase in osteoblast activity were observed in the distracted callus in the G-CSF group, whereas, at the late phase of consolidation, a significantly lower neovascularization was observed. While no difference was observed in the number of circulating EPCs between control and G-CSF groups, the number of MSCs was significantly lower at the end of the latency phase and that of HSPCs was significantly higher 4 days after the bone lengthening. Our results indicate that G-CSF accelerates bone regeneration and modulates mobilization of progenitor cells during DO.

Distance from the magnification device contributes to differences in lower leg length measured in patients with TSF correction

Introduction In absence of deformity or injury of the contralateral leg, the contralateral leg length is used to plan limb lengthening. Length variability on long-leg weight-bearing radiographs (LLR) can lead to inaccurate deformity correction. The aim of the study was to (1) examine the variability of the measured limb length on LLR and (2) to examine the influence of the position of the magnification device. Materials and methods The limb lengths of 38 patients during deformity correction with a taylor-spatial-frame were measured retrospectively on 7.3 ± 2.6 (4–13) LLR per patient. The measured length of the untreated limb between LLR were used to determine length variability between LLR in each patient. To answer the secondary aim, we took LLR from a 90 cm validation distance. A magnification device was placed in different positions: at the middle of the 90 cm distance (z-position), 5 cm anterior and 5 cm posterior from the z-position, at the bottom and top of the validation distance as well as 5 cm medial and 15 cm lateral from the z-position. Results The measured length variability ranged within a patient from 10 to 50 mm. 76% of patients had a measured limb length difference of ≥ 2 cm between taken LLR. Compared to length measurement of the 90 cm test object with the magnification device in the z-position (90.1 cm), positioning the device 5 cm anterior led to smaller (88.6 cm) and 5 cm posterior led to larger measurements (91.7 cm). The measured length with the magnification device at the bottom, top, medial or lateral (90.4; 89.9; 90.2; 89.8 cm) to the object differed not relevantly. Conclusions High variability of limb length between different LLR within one patient was observed. This can result from different positions of the magnification device in the sagittal plane. These small changes in positioning the device should be avoided to achieve accurate deformity correction and bone lengthening. This should be considered for all length and size measurements on radiographs.