Proximal Tibial Growth Plate Research Articles

Case Report: Halting terminal osseous overgrowth post tibia amputation in children: a report of three cases

Terminal osseous overgrowth is a common complication after trans-diaphyseal amputation in children, leading to pain, soft tissue problems, and recurrent surgical procedures. We report three different cases with post-amputation issues of osseous overgrowth, ulceration, and deformity over the amputation site. The first case involves a 9-year-old boy with a right leg congenital amputation secondary to amniotic band syndrome. The right below-knee stump later experienced recurrent episodes of osseous overgrowth, leading to ulceration. After the prominent tibia was resected and capped with the ipsilateral proximal fibula, a positive outcome was achieved with no more recurrent overgrowth over the right leg stump. The second case involves a 9-year-old girl born with an amniotic constriction band over both legs. Her left leg remained functional after a circumferential Z-plasty, but the right leg was a congenital below-knee amputation. Multiple refashioning surgeries were performed on the right leg due to osseous overgrowth but the patient continued to experience recurrent overgrowth causing pain and difficulty fitting into a prosthesis. We performed osteocartilaginous transfer of the proximal part of the ipsilateral fibula to the right tibial end, successfully preventing the overgrowth of the tibia without any complications. The third case involves an 11-year-old boy with a history of meningococcal septicemia who underwent a right below-knee amputation and left ankle disarticulation due to complications of septic emboli. He experienced a prominent right distal tibia stump, which later developed into valgus deformity as a result of the previous insult to the proximal tibial growth plate. We performed a corrective osteotomy over the proximal right tibia and capped the entire tibia with the ipsilateral fibula as an intramedullary splint for the osteotomy site. Post-operatively, we achieved satisfactory deformity correction and successfully halted the recurrent overgrowth over the right tibia stump. The method of ipsilateral fibula capping is safe and effective in managing the osseous overgrowth complications in trans-diaphyseal amputations among children. Therefore, it is a reasonable option during primary below-knee amputations in children compared to multiple refashioning surgeries.

Subperiosteal delivery of transforming growth factor beta 1and human growth hormone from mineralized PCL films.

The ability to locally deliver bioactive molecules to distinct regions of the skeleton may provide a novel means by which to improve fracture healing, treat neoplasms or infections, or modulate growth. In this study, we constructed single-sided mineral-coated poly-ε-caprolactone membranes capable of binding and releasing transforming growth factor beta 1 (TGF-β1) and human growth hormone (hGH). After demonstrating biological activity in vitro and characterization of their release, these thin bioabsorbable membranes were surgically implanted using an immature rabbit model. Membranes were circumferentially wrapped under the periosteum, thus placed in direct contact with the proximal metaphysis to assess its bioactivity in vivo. The direct effects on the metaphyseal bone, bone marrow, and overlying periosteum were assessed using radiography and histology. Effects of membrane placement at the tibial growth plate were assessed via physeal heights, tibial growth rates (pulsed fluorochrome labeling), and tibial lengths. Subperiosteal placement of the mineralized membranes induced greater local chondrogenesis in the plain mineral and TGF-β1 samples than the hGH. More exuberant and circumferential ossification was seen in the TGF-β1 treated tibiae. The TGF-β1 membranes also induced hypocellularity of the bone marrow with characteristics of gelatinous degeneration not seen in the other groups. While the proximal tibial growth plates were taller in the hGH treated than TGF-β1, no differences in growth rates or overall tibial lengths were found. In conclusion, these data demonstrate the feasibility of using bioabsorbable mineral coated membranes to deliver biologically active compounds subperiosteally in a sustained fashion to affect cells at the insertion site, bone marrow, and even growth plate.

Microwave Ablation of the Pig Growth Plate: Proof of Concept for Minimally Invasive Epiphysiodesis.

Different surgical methods for epiphysiodesis of limb length discrepancy (LLD) have been described. Although these methods are variably effective, they are associated with morbidity (pain and limp) and potential complications. Microwave ablation is a less-invasive opportunity to halt growth by selectively destroying the growth plate via thermal energy to treat LLD in children. In this proof-of-concept study using an in vivo pig model, we asked: (1) What is the durability of response 2 to 4 months after microwave ablation of the tibial growth plate as measured by length and angulation of the tibia via a CT scan? (2) Was articular cartilage maintained as measured by standard histologic staining for articular cartilage viability? To develop an in vivo protocol for microwave ablation, we placed microwave antennas adjacent to the proximal tibia growth plate in the cadaveric hindlimbs of 18 3-month-old pigs. To determine the suitable time, we varied ablation from 90 to 270 seconds at 65-W power settings. After sectioning the tibia, we visually assessed for discoloration (implying growth plate destruction) that included the central growth plate but did not encroach into the epiphysis in a manner that could disrupt the articular surface. Using this information, we then performed microwave ablation on three live female pigs (3.5 to 4 months old) to evaluate physiologic changes and durability of response. A postprocedure MRI was performed to ensure the intervention led to spatial growth plate alterations similar to that seen in cadavers. This was followed by serial CT, which was used to assess the potential effect on local bone and growth until the animals were euthanized 2 to 4 months after the procedure. We analyzed LLD, angular deformity, and bony deformity using CT scans of both tibias. The visibility of articular cartilage was compared with that of the contralateral tibia via standard histologic staining, and growth rates of the proximal tibial growth plate were compared via fluorochrome labeling. Eighteen cadaveric specimens showed ablation zones across the growth plate without visual damage to the articular surface. The three live pigs did not exhibit changes in gait or require notable pain medication after the procedure. Each animal demonstrated growth plate destruction, expected limb shortening (0.8, 1.2, and 1.5 cm), and bony cavitation around the growth plate. Slight valgus bone angulation (4º, 5º, and 12º) compared with the control tibia was noted. No qualitatively observable articular cartilage damage was encountered from the histologic comparison with the contralateral tibia for articular cartilage thickness and cellular morphology. A microwave antenna placed into a pig's proximal tibia growth plate can slow the growth of the tibia without apparent pain and alteration of gait and function. Further investigation and refinement of our animal model is ongoing and includes shorter ablation times and comparison of dynamic ablation (moving the antennae during the ablation) as well as static ablation of the tibia from a medial and lateral portal. These refinements and planned comparison with standard mechanical growth arrest in our pig model may lead to a similar approach to ablate growth plates in children with LLD.

Adaptations of bone and bone vasculature to muscular stretch training.

The magnitude of bone formation and remodeling is linked to both the magnitude of strain placed on the bone and the perfusion of bone. It was previously reported that an increase in bone perfusion and bone density occurs in the femur of old rats with moderate aerobic exercise training. This study determined the acute and chronic effects of static muscle stretching on bone blood flow and remodeling. Old male Fischer 344 rats were randomized to either a naive or stretch-trained group. Static stretching of ankle flexor muscles was achieved by placement of a dorsiflexion splint on the left ankle for 30min/d, 5d/wk for 4wk. The opposite hindlimb served as a contralateral control (nonstretched) limb. Bone blood flow was assessed during and after acute stretching in naive rats, and at rest and during exercise in stretch-trained rats. Vascular reactivity of the nutrient artery of the proximal tibia was also assessed in stretch-trained rats. MicroCT analysis was used to assess bone volume and micro-architecture of the trabecular bone of both tibias near that growth plate. In naive rats, static stretching increased blood flow to the proximal tibial metaphasis. Blood flow to the proximal tibial metaphysis during treadmill exercise was higher in the stretched limb after 4wk of daily stretching. Daily stretching also increased tibial bone weight and increased total volume in both the proximal and distal tibial metaphyses. In the trabecular bone immediately below the proximal tibial growth plate, total volume and bone volume increased, but bone volume/total volume was unchanged and trabecular connectivity decreased. In contrast, intravascular volume increased in this region of the bone. These data suggest that blood flow to the tibia increases during bouts of static stretching of the hindlimb muscles, and that 4wk of daily muscle stretching leads to bone remodeling and an increase in intravascular volume of the tibial bone.

Is the ratio of the index to ring finger length, a potential marker for prenatal testosterone-estrogen balance, related to posterior tibial slope?

BackgroundThe 2D:4D ratio, an indicator of prenatal testosterone-estrogen balance, is the index finger (second finger) size's ratio to the ring finger (fourth finger) size. Asymmetric growth in the proximal tibial growth plate is considered to cause the increased posterior tibial slope (PTS) formation. Factors determining the amount of this asymmetry still need clarification. This study aims to evaluate the relationship between the 2D:4D ratio, which indicates the prenatal testosterone-estrogen balance, and the PTS. MethodMeeting the study criteria, 267 patients were included in the study. We measured the medial PTS (MPTS) and lateral PTS (LPTS) on MRI images and the lengths of the second and fourth fingers on both hands of the patients. Additionally, we compared 2D:4D ratios and MPTS and LPTS measurements. ResultsWe found a significant negative correlation between MPTS and the 2D:4D ratio, as well as between LPTS and the 2D:4D ratio in both hands (MPTS left vs. right hand: P < 0.001, r = −0.627 vs. P < 0.001, r = −0.498) (LPTS left vs. right hand: P < 0.001, r = 0.589 vs. P < 0.001, r = 0.404). Separately among males and females, there was a significant negative correlation between MPTS and the 2D:4D ratio, as well as between LPTS and the 2D:4D ratio in both hands (for males: MPTS left vs. right hand: P < 0.001, r = −0.607 vs. P < 0.001, r = −0.540)(for males: LPTS left vs.right hand: P < 0.001, r = 0.451 vs. P < 0.001, r = 0.406) (for females:MPTS left vs. right hand: P < 0.001, r = −0.638 vs. P < 0.001, r = −0.446) (for females:LPTS left vs.right hand: P < 0.001, r = 0.618 vs. P < 0.001, r = 0.403). ConclusionsThe 2D:4D ratio, an indicator of intrauterine testosterone-estrogen balance, is related to PTS. The effect of testosterone on the growth plate of the proximal tibia may be one of the factors determining the PTS value.Level of evidence: III retrospective comparative study.

Injectable hydrogel loaded with bilayer microspheres to inhibit angiogenesis and promote cartilage regeneration for repairing growth plate injury.

Introduction: The repair and regeneration of growth plate injuries using tissue engineering techniques remains a challenge due to large bone bridge formation and low chondrogenic efficiency. Methods: In this study, a bilayer drug-loaded microspheres was developed that contains the vascular endothelial growth factor (VEGF) inhibitor, Bevacizumab, on the outer layer and insulin-like growth factor-1 (IGF-1), a cartilage repair factor, on the inner layer. The microspheres were then combined with bone marrow mesenchymal stem cells (BMSCs) in the gelatin methacryloyl (GelMA) hydrogel to create a composite hydrogel with good injectability and biocompatibility. Results: The in vitro drug-release profile of bilayer microspheres showed a sequential release, with Bevacizumab released first followed by IGF-1. And this hydrogel simultaneously inhibited angiogenesis and promoted cartilage regeneration. Finally, in vivo studies indicated that the composite hydrogel reduced bone bridge formation and improved cartilage regeneration in the rabbit model of proximal tibial growth plate injury. Conclusion: This bilayer microsphere-based composite hydrogel with sequential controlled release of Bevacizumab and IGF-1 has promising potential for growth plate injury repair.

The regenerative treatment of costal osteochondral graft implantation for partial growth arrest using a rabbit model

PurposeTo investigate the feasibility of cylindrical costal osteochondral graft transplantation as a novel regenerative treatment in growth arrest. MethodsThe medial portion of the proximal tibial growth plate of 6-week-old male New Zealand White rabbits was resected to establish an experimental model of partial growth plate injury. The rabbits were divided into four groups: no-treatment, bone wax transplantation, costal chondral graft, and costal osteochondral graft groups. Radiographic and micro-computed tomography scan results were analyzed to evaluate angular deformity of the tibia and bony bridge formation at the injury site. In addition, repair of the injured growth plate cartilage was assessed histologically at 4, 8, and 12 weeks postoperatively. ResultsRadiographic examination revealed that bone wax transplantation continuously decreased the medial proximal tibial angle (MPTA) while the costal chondral graft implantation reduced the decrease of MPTA at 12 weeks postoperatively. The costal osteochondral graft implantation recovered the MPTA, close to the normal. Histologically, the costal osteochondral grafts retained the MPTA in the injured site compared to costal chondral grafts. Additionally, hypertrophic chondrocytes were observed at the graft site in the costal osteochondral graft group at 12 weeks, suggesting that endochondral ossification may occur at the graft site similar to normal ossification. The fluorescence in situ hybridization analysis of osteochondral grafts transplanted from male to female rabbits indicated that they were replaced by cells of host origin. ConclusionThe costal osteochondral graft can achieve regeneration without bony bridge formation in partial growth plate injury.

Gut microbiome dysregulation drives bone damage in broiler tibial dyschondroplasia by disrupting glucose homeostasis

Tibial dyschondroplasia (TD) with multiple incentives is a metabolic skeletal disease that occurs in fast-growing broilers. Perturbations in the gut microbiota (GM) have been shown to affect bone homoeostasis, but the mechanisms by which GM modulates bone metabolism in TD broilers remain unknown. Here, using a broiler model of TD, we noted elevated blood glucose (GLU) levels in TD broilers, accompanied by alterations in the pancreatic structure and secretory function and damaged intestinal barrier function. Importantly, faecal microbiota transplantation (FMT) of gut microbes from normal donors rehabilitated the GM and decreased the elevated GLU levels in TD broilers. A high GLU level is a predisposing factor to bone disease, suggesting that GM dysbiosis-mediated hyperglycaemia might be involved in bone regulation. 16S rRNA gene sequencing and short-chain fatty acid analysis revealed that the significantly increased level of the metabolite butyric acid derived from the genera Blautia and Coprococcus regulated GLU levels in TD broilers by binding to GPR109A in the pancreas. Tibial studies showed reduced expression of vascular regulatory factors (including PI3K, AKT and VEFGA) based on transcriptomics analysis and reduced vascular distribution, contributing to nonvascularization of cartilage in the proximal tibial growth plate of TD broilers with elevated GLU levels. Additionally, treatment with the total flavonoids from Rhizoma drynariae further validated the improvement in bone homoeostasis in TD broilers by regulating GLU levels through the regulation of GM to subsequently improve intestinal and pancreatic function. These findings clarify the critical role of GM-mediated changes in GLU levels via the gut–pancreas axis in bone homoeostasis in TD chickens.

Mesenchymal cell-derived Wnt1 signaling regulates subchondral bone remodeling but has no effects on the development of growth plate or articular cartilage in mice.

Chondrocyte differentiation is a principal progress in endochondral ossification and in the formation of secondary ossification center (SOC) during the long bone development. We have previously reported that targeted deletion of Wnt1 in mesenchymal progenitors (Wnt1Prrx-/-) leads to spontaneous fractures and severe osteopenia in mouse long bones, suggesting that Wnt1 is a key regulator of bone metabolism. However, the effect of Wnt1 on the regulation of cartilage development and chondrocyte differentiation remained unknown. In this study, WNT1 protein expression was observed in lateral superficial cartilage and growth plate pre-hypertrophic chondrocytes in mice. Wnt1 mRNA expression was detected in epiphyseal cartilage from E16.5 to 3month-old mice. Detailed histological analyses revealed that the average thickness and chondrocyte density of proximal tibial articular cartilage and growth plate were unchanged between Wnt1Prrx-/- and control mice. However, μCT analysis of tibial epiphyses showed that the subchondral bone mass was reduced in Wnt1Prrx-/- mice compared to control mice, as demonstrated by decreased bone volume, trabecular number, trabecular thickness, and increased trabecular separation in Wnt1Prrx-/- mice. Mechanistically, histomorphometric analyses showed that the reduced subchondral bone mass in Wnt1Prrx-/- mice was due to impaired bone formation and enhanced bone resorption. In vitro, exogenous Wnt1 inhibited chondrogenesis and chondrocyte hypertrophy in both cell autonomous and juxtacrine manners, while matrix mineralization and the expression of Mmp13, Mmp9 and Opn were induced in a juxtacrine manner. Taken together, mesenchymal cell-derived Wnt1 is an important regulator of subchondral bone remodeling, although it has no effect on the regulation of growth plate or articular cartilage.

Surgical and medical management in the treatment of proximal tibial metaphyseal fracture in immature dogs.

The purpose of this study was to report approaches to surgical and medical management of proximal tibial metaphyseal fractures (PTMF) and short-term case outcome. Medical records of immature dogs with PTMF were reviewed and data were collected including history, signalment and side affected. Data pertaining to surgical and medical management including radiographic evaluation and short-term complications were recorded. Forty-five dogs with a total of 47 PTMF identified and treated between 2007-2019 were included in this study. Six cases were managed with external coaptation alone. Forty-one cases were treated surgically with constructs including K-wires in different configurations, bone plate and screws, and external skeletal fixation. Of the cases managed conservatively, 4 developed complications, including bandage sores, diffuse osteopenia of the tarsus/metatarsus, and angular limb deformities. Surgical complications including pin migration necessitating removal, osteopenia, and screw placement in the proximal tibial growth plate or into the stifle joint were found in 16 cases. PTMF treated with surgery had a subjectively more predictable outcome compared to those treated with external coaptation alone. Conservative management may result in complications including development of excessive tibial plateau angle (TPA) as well as distal tibial valgus.

Differential regulation of IGF‐1 pathway and accelerated bone elongation in pre‐obese juvenile mice

INTRODUCTIONChildhood obesity is driven, in large part, by increased dietary fat intake. Accelerated bone growth, a hallmark of juvenile obesity but one of its most overlooked complications, can lead to irreversible skeletal damage and chronic adult disability. Paradoxically, obese children typically have low to normal circulating levels of the growth promoting hormone insulin‐like growth factor‐1 (IGF‐1), despite their accelerated growth rate. However, IGF‐1 is both an endocrine and paracrine hormone that is essential for endochondral ossification, the process by which bones lengthen in cartilaginous growth plates at the ends of long bones. We previously reported that pre‐obese juvenile mice on a high‐fat diet have increased cell proliferation in growth plates without changes in serum IGF‐1, and before significant changes in body mass were evident. Our goal was to determine whether a high‐fat diet alters local IGF‐1 activity in growth plates by using gene set enrichment analysis on RNA sequencing (RNA‐Seq) data. We tested theHYPOTHESISthat juvenile mice on a high‐fat diet will exhibit an upregulation of IGF‐1 pathways in the growth plate.METHODSMale and female 3‐week old C57BL/6 mice were weaned on to high‐fat diet (60% kCal of fat) or control diets (10% kCal of fat) for 2 weeks and examined at 5‐weeks age when bones are elongating faster in high‐fat diet mice. We developed and validated a manual dissection technique to isolate proximal tibial growth plates from surrounding bone for RNA and protein analyses on cartilage. RNA was isolated from pooled left and right tibial growth plates and sent to the Marshall Genomics Core for next generation sequencing using an Illumina NextSeq 2000 Sequencer. Data were analyzed using fast gene set enrichment analysis (version 1.20.0) along with the reactome pathway database (version 78). Enrichment scores were calculated based on the degree to which genes in a given pathway were up‐ or down‐regulated in the RNA‐Seq data set. These scores are then normalized to account for the different number of genes involved in each pathway set and compared between diets.RESULTSOur data show that pathways regulating IGF‐1 transport and uptake by insulin‐like growth factor binding proteins (IGFBPs) were upregulated in mice on a high‐fat diet with a normalized enrichment score (NES) of 2.17 (Benjamini‐Hochberg adjusted p‐value&lt;0.01). Components of this pathway included, among others, individual IGFBPs (Igfbp4 and Igfbp5) and an IGFBP protease inhibitor (Stc2).DISCUSSIONSignificant changes in the IGF‐1 pathway closely followed those involved in cell metabolism and muscle contraction, suggesting that regulating IGF‐1 activity could be a main driver of diet‐induced growth acceleration. These data are consistent with our hypothesis that a high‐fat diet increases local IGF‐1 activity in growth plates even though systemic IGF‐1 remains unchanged.SIGNIFICANCEThese data are relevant for understanding mechanisms of diet‐induced growth acceleration and provide important groundwork for subsequent efforts to identify specific components of the IGF‐1 pathway that could underlie rapid skeletal growth in juvenile obesity.

Lower limb deformities and limb length discrepancies in hereditary multiple exostoses.

There is a high rate of lower limb deformity and limb length discrepancy in patients with hereditary multiple exostoses (HME). The aim of this study was to evaluate the type and frequency of lower limbs axial deviation and limb length discrepancy and the type of exostoses being risk factors for theses deformities. We retrospectively reviewed standing full-length radiograph of 32 HME patients (64 limbs) followed in our institution between October 2009 and December 2020. Patient demographics were recorded. Radiographic analysis of the coronal limb alignment was performed, limb length discrepancy was measured and topography of the exostoses was recorded. We propose a classification of lower legs in 2 groups and 4 types according to the presence and the location of exostoses. In group I, there is an intertibio- fibular exostose with fibular origin at the level of the tibiofibular joints. In type IA, at the level of the distal tibiofibular joint with ascension of the distal fibula; in type IB at the level of the proximal tibiofibular joint with a bracketing effect on the proximal tibia and a lateral slope of the proximal tibial growth plate; the type IC is combining features of both IA and IB. In group II, there is no intertibio-fibular exostose coming from the fibula and no growth abnormality is obvious. A clinically notable lower limb discrepancy (LLD) of ≥2 cm was found in 19% of our patients. Approximately 33% of patients had a knee valgus deformity and 44% had an ankle valgus deformity. The knee valgus deformity was due to fibular growth anomalies and not to distal femur anomalies. The majority of lower legs had fibular growth anomalies (72%) which was a significant risk factor for knee valgus deformity and leg length discrepancy. On the contrary, we found no correlation between number, location and volume of distal femoral exostoses and genu valgum nor leg length discrepancy. Presence of intertibio-fibular exostoses is a risk factor for knee valgus deformity and leg length discrepancy. The presence of these exostoses should lead to a close follow-up of the patient.

Rebound predictors of varus-valgus deformities around the knee corrected by guided growth.

Coronal plane deformities around the knee are rather common condition in children. Guided growth by temporary hemiepiphysiodesis is considered to be the preferred primary treatment in many cases. Despite the popularity of hemiepiphysiodesis, the incidence of recurrence of deformity and predictors for rebound are not well defined. The objectives of this study were to determine the incidence of the recurrence of varus-valgus deformities around the knee treated by temporary hemiepiphysiodesis and possible predictors for the rebound. We retrospectively reviewed medical records and x-ray images of 130 patients with varus-valgus deformities around the knee treated by tension-band (eight-plate) hemiepiphysiodesis, between the years 2006 and 2016 in our institution. The incidence of rebound of varus-valgus deformities around the knee and possible predictors were analyzed. Rebound of the deformity was observed in 10% of patients. Risk factors found to be in correlation with recurrence include young age, deformity of proximal tibia, proximal tibial medial growth plate beaking, and comorbidities (like metabolic disorders, multiple hereditary exostoses and genetic syndromes). The results of this study show that there is a noteworthy incidence of rebound in patients treated by temporary hemiepiphysiodesis for coronal deformities around the knee. The risk factors are also outlined. These patients, especially the ones with risk factors, require close surveillance until maturity. Level III-Case control study.

Напружено-деформований стан проксимального відділу великогомілкової кістки дитини при tibia vara в умовах однобічного блокування проксимальної росткової зони фіксаторами різних типів

Актуальність. Сучасним стандартом хірургічного лікування фронтальних епіметафізарних деформацій колінного суглоба у дітей є метод керованого росту. Для тимчасового блокування росткової зони використовуються різні фіксатори: скоби Блаунта, пластини з гвинтами. Проте дослідження, присвячені вивченню напружено-деформованого стану при використанні зазначених фіксаторів, відсутні.Мета: дослідження напружено-деформованого стану моделі проксимального відділу великогомілкової кістки дитини при однобічному блокуванні росткової зони фіксаторами різних типів в умовах навантажень, характерних для tibia vara.Матеріали і методи. За допомогою програми Solid Works створена і проаналізована методом кінцевих елементів 3D-модель проксимального відділу великогомілкової кістки дитини з латеральним блокуванням одним із 3 фіксаторів: скоба Блаунта, блокована пластина, стандартна пластина в умовах навантаження, характерних для tibia vara.Результати. В умовах навантаження, характерних для tibia vara, відзначено збільшення напружень у медіальній частині росткової зони. При однобічному блокуванні фіксаторами виявлено нові зони підвищених навантажень у кістковій тканині метаепіфіза нижче від росткової зони. Найбільше напруження у фіксаторах відзначено в зоні контакту проксимального гвинта з пластиною, а також у верхній частині скоби.Висновок. Варусна деформація проксимального відділу великогомілкової кістки веде до підвищення навантажень у медіальній частині проксимальної росткової зони. Використання різних фіксаторів для однобічного блокування проксимальної росткової зони великогомілкової кістки призводить до появи відмінних напружень у проксимальному її епіметафізі. До мінімального підвищення напружень у кістковій тканині метафіза приводять варіанти фіксації із застосуванням пластин, а використання скоб Блаунта значно підвищує напруження в кістковій тканині в ділянці розташування скоб.

Evaluation of Intra-Articular Injection of Bevacizumab on the Prevention of Physeal Bar Formation in Type 4 Salter Harris Model in Rats: A Pilot Study

Background: This study was designed to achieve a new method as a preventive treatment for complications of growth plate fractures. In this study, we investigate the effect of intra-articular injection of anti-vascular endothelial growth factor (anti-VEGF) antibody bevacizumab on the repair process of articular cartilage in a type 4 Salter Harris injury model.&#x0D; Methods: A Salter Harris injury was created on the proximal tibial growth plate of 14 rats by a 1.8 mm drill. The rats were randomly classified into two groups: group LD, administration of high-dose intra-articular injection of bevacizumab (250 μg), and group HD, administration of low-dose intra-articular injection of bevacizumab (50 μg) after injury. The rats were killed 2 months postoperatively and their tibia underwent micro-computed tomography (CT) analysis, histological assessment, and measurement of tibial bone length.&#x0D; Results: Bony bar formation was observed in 71% of the samples in the high-dose group and in 100% of the low-dose group. Relative increase in physeal cartilage thickness (P = 0.007) and decrease in bony bar formation (P = 0.029) were observed significantly in the high dose group. There was no significant difference in tibia length between the two groups (P = 0.150).&#x0D; Conclusion: Intra-articular administration of bevacizumab demonstrated positive restorative effects. We suggest this method of treatment due to its potential of improving cartilage repair and capability to be used as a main or adjacent treatment in osteochondral defects.

Varus knee deformity in adolescent soccer players

The lower limb axis develops dynamically throughout the first and second decades of life. In recent years, with respect to youth athletes, we have been facing a progressive increase in the intensity of exercise during training and competition (involving increased time, frequency, and power), and, as a result, there hasbeen an increase in the number of acute and chronic overuse injuries. There are some sports with a higher incidence of injuries, one of which is soccer. A review of literature for the past 15 years with a focus on varus knee deformities in adolescent soccer players showed that varus axial deformities of the lower limbsoccur more frequently in soccer players than in the general population and in athletes from other sport, probably due to the specific loading pattern in soccer training. Varus deformities alter knee biomechanics, which results in medial joint space overloading, and consequently an early onset of degenerative joint disease. In addition, bowlegs predisposes athletes to patellofemoral pain syndrome and meniscal lesions. The etiology of genu varum in soccer is thought to be multifactorial, ranging from the natural selection of players to mechanical overload of the proximal medial tibial growth plate. A growing number of clinical reports and animal studies have indicated that intensive sport training may precipitate pathologic changes of the knee joint growth plate, and even produce a growth disturbance.

Intramedullary Nailing of Paediatric Tibial Fractures: Comparison between Flexible and Rigid Nails.

To describe patient characteristics and to compare outcomes of children undergoing rigid intramedullary nailing of tibial fractures as compared with those operated on using elastic intramedullary nailing. A retrospective review of 26 children who have undergone flexible intramedullary nailing of tibial fractures and 30 children with rigid nailing at our university hospital between 2008 and 2017. The patient charts and radiographs were evaluated to identify demographic characteristics and several variables were measured preoperatively, as well as 6-12 weeks postoperatively in addition to final follow-up radiographs. Twenty-six patients (26/26, 100%) treated with a flexible nail and 14 patients (14/30, 46.7%) treated with a rigid nail had open proximal tibial physis (p < 0.001). An acceptable postoperative alignment was obtained in 20 patients (20/26, 76.9%) in the elastic stable intramedullary nail group and in 29 patients (29/30, 96.7%) in the rigid group (p = 0.026). Some complications occurred in four patients (4/26, 15%) in the elastic stable intramedullary nail population and seven patients (7/30, 23%) in the rigid intramedullary nail population (p = 0.46). Malunion occurred in six patients (6/26, 23%) in the elastic stable intramedullary nail group and in none of the patients treated with a rigid intramedullary nail (p = 0.005). Younger children with tibial fractures who weight 50 kg or less and with proximal tibial growth plates wide open can be treated with elastic stable intramedullary nail while more mature adolescents benefit from rigid intramedullary nailing.

Gamma Aminobutyric Acid-Enriched Fermented Oyster (Crassostrea gigas) Increases the Length of the Growth Plate on the Proximal Tibia Bone in Sprague-Dawley Rats.

Bone growth during childhood and puberty determines an adult’s final stature. Although several prior studies have reported that fermented oyster (FO) consisting of a high amount of gamma aminobutyric acid can be attributed to bone health, there is no research on the efficacy of FO on growth regulation and the proximal tibial growth plate. Therefore, in this study, we investigated the effect of FO oral administration on hepatic and serum growth regulator levels and the development of the proximal tibial growth plate in young Sprague-Dawley rats. Both oral administration of FO (FO 100, 100 mg/kg FO and FO 200, 200 mg/kg FO) and subcutaneous injection of recombinant human growth hormone (rhGH, 200 μg/kg of rhGH) for two weeks showed no toxicity. Circulating levels of growth hormone (GH) significantly increased in the FO 200 group. The expression and secretion of insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) were enhanced by FO administration. FO administration promoted the expression of bone morphogenic proteins IGF-1 and IGFBP-3 in the proximal tibial growth plate. This positive effect of FO resulted in incremental growth of the entire plate length by expanding the proliferating and hypertrophic zones in the proximal tibial growth plate. Collectively, our results suggested that oral administration of FO is beneficial for bone health, which may ultimately result in increased height.

Risk Factors for Arthrofibrosis in Tibial Spine Fractures: A National 10-Site Multicenter Study

Objectives:To identify risk factors for developing arthrofibrosis after TSF treatment.Methods:This was a retrospective, multi-center study across ten institutions of 448 patients <25 years old who presented to care with a tibial spine fracture between 1/2000 and 2/2019. Patient records were reviewed for a multitude of pre-operative, intra-operative, and post-operative characteristics. Patients were then separated into two cohorts based on if they suffered from post-treatment arthrofibrosis.Results:Chart review demonstrated that 43 (9.6%) of the patients suffered from post-treatment arthrofibrosis. There were no demographic differences observed between the two groups. However, based on MRIs at the time of injury, distal femoral and proximal tibial growth plates were more frequently closed in the arthrofibrosis group (17.6% vs 4.4%, p=0.023 for both comparisons). Additionally, there was no difference in Meyers & McKeever (MM) classification (p=0.597). All arthrofibrosis patients received operative treatment (p=0.003), though there was no difference in fixation technique (p=0.734). Intraoperatively, a higher number of screws were used in the arthrofibrosis group (p=0.002) with the placement of hardware more likely to be epiphyseal (p=0.007). Other operative parameters including number of sutures were not different. Post-operatively, arthrofibrosis patients were more likely to have been immobilized in a cast (p<0.001) with no difference observed for weight-bearing status. After multivariate regression, screw number (OR 8.9, CI 1.9-41.7, p=0.005) and immobilization in a cast (OR 7.8, CI 1.0-60.4, p=0.049) remained significant predictors of post-treatment arthrofibrosis.Conclusion:This serves as the largest study of tibial spine fractures to analyze risk factors for the development of post-treatment arthrofibrosis. Our study demonstrates that pre-operative factors were largely similar between groups, but that intra-operative decisions, including the number of screws used for fixation and placement of hardware in relation to the physis, were significant predictors of post-treatment arthrofibrosis. These findings may influence operative decision-making in tibial spine fracture patients. Additionally, post-operative immobilization in a cast should be avoided given the high risk of arthrofibrosis.Table 1.Characteristics of patients with post-operative arthrofibrosis Arthrofibrosis (N=43) No Arthrofibrosis (N=405) P-value Demographic Age (years)11.112.00.065Male: Female ration24:19282:1230.064BMI20.220.40.824 Injury Sports-related (%)13 (30.2)205 (50.4) 0.012 MM classification III/IV20 (64.5)134 (59.6)0.597Concomitant ACL injury (%)5 (22.7)46 (21.6)0.902Delay to surgery (days)24.224.30.989 Operative Received surgery (%)43 (100.0)325 (78.5) 0.003 Operative time (min)142.0123.90.209Treatment type (%) ARIF36 (83.7)269 (82.8)0.734ORIF7 (16.3)45 (13.8) Screws (%)22 (51.2)114 (35.5) 0.046 Number of Screws1.81.4 0.002 Screw/Suture Placement (%) 0.005 Transphyseal5 (17.9)94 (44.5) 0.007 Epiphyseal23 (82.1)117 (55.5) Post-operative 41 (97.6)305 (97.8) Immobilized21 (51.2)72 (23.7)0.955Cast immobilization16 (39.0)208 (68.2) <0.001 Non-weightbearing11 (34.4)72 (25.4)0.277

A new standard radiographic reference for proximal fibular height in children

Background and purpose — To date there is a lack of studies defining the anatomical position of the proximal fibula. This is especially relevant when planning surgical interventions affecting the knee joint such as permanent or temporary epiphysiodesis to correct leg length discrepancies or angular deformities in growing patients. The goal of this study is to establish a standardized measurement technique and radiological reference values for the position of the proximal fibula in children.Patients and methods — 500 measurements were performed in calibrated long standing anteroposterior radiographs of 256 skeletally immature patients (8–16 years; 233 female, 267 male legs). As a radiographic reference in the frontal plane, the distance between the center of the proximal tibial growth plate and a line tangential to the tip of the fibular head and horizontal to the imaging plane was measured (dPTFH).Results — The average value of dPTFH in the studied population (median age 12 years) was –2.7 mm (SD 3, CI –3.0 to –2.5) and normally distributed (p = 0.1). There were no clinically significant sex or age-dependent differences. The inter-rater reliability analysis showed excellent ICC values (ICC = 0.88; CI 0.77–0.93).Interpretation — This study provides a new radiographic reference value to assess the position of the proximal fibula in relation to the proximal tibia in children and adolescents. This reference can aid preoperative decision-making as to whether additional fibular epiphysiodesis is necessary when performing tibial epiphysiodesis to correct moderate leg-length discrepancies.