Prediction of the Labrum Shape in Patients With Developmental Dysplasia of the Hip Based on Pelvic Radiography.

BACKGROUND: The shape of the labrum is strongly correlated with outcomes of developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) is the generally preferred imaging technique for observing the labrum. PURPOSE: We aimed to find a correlation between the labrum shape and anterior-posterior (AP) pelvic measurements in children with DDH. METHODS: Preoperative AP pelvic x-ray radiographs and MRI of patients with DDH from January 2019 to December 2021 were retrospectively collected and divided into three groups by labrum shape on MRI: everted, partly inverted, and inverted. The acetabular length ratio (RAL) in patients with unilateral DDH and the ratio of acetabular length to interpedicular distance (RALI) in all patients were calculated. T-tests were used to analyze differences between the groups. Receiver operating characteristic curve (ROC) analysis was performed between the everted group and the partly inverted and inverted groups. RESULTS: We found significant differences in RAL between the everted and partly inverted groups, everted and inverted groups, and everted and combined groups. The ROC analysis showed that the best cutoff value for RAL was 0.945 between the everted and combined groups, with an area under the curve (AUC) of 88.4%. The sensitivity at the best RAL value was 0.783, and the specificity was 0.887. Moreover, we observed a significant difference in RALI between the everted, partly inverted, and inverted groups, as well as between the everted and combined groups. The optimal cutoff value for RALI between the everted and combined groups was 0.575, with an AUC of 74.5%. The sensitivity at the best RALI value was 0.765, and the specificity was 0.674. CONCLUSION: The RAL or RALI values on pelvic AP radiographs can be used to predict the shape of the labrum. LEVEL OF EVIDENCE: III.

Assessment of ulnar nerve stability at the elbow by ultrasonography in children.

BACKGROUND: Elbow fractures are common in children. While Kirschner wire (K-wire) is the most commonly used fixation material in children, medial entry pins may be needed for fracture stability. This study aimed to assess ulnar nerve instability by ultrasonography in children. METHODS: We enrolled 466 children aged 2 months to 14 years between January 2019 and January 2020. There were at least 30 patients in each age group. Ulnar nerves were observed under the ultrasound equipment with the elbow fully extended and flexed. If ulnar nerves were subluxated or dislocated, they were considered to have ulnar nerve instability. The children's clinical data, including sex, age, and elbow sides, were analyzed. RESULTS: Of 466 enrolled children, 59 had ulnar nerve instability. Ulnar nerve instability rate was 12.7% (59/466). Instability was prevalent in children aged 0-2 years (P = .001). Among 59 children with ulnar nerve instability, 52.5% (31/59) had bilateral ulnar nerve instability, 16.9% (10/59) had right ulnar nerve instability, and 30.5% (18/59) had left ulnar nerve instability. Logistic analysis of the risk factors of ulnar nerve instability showed no significant difference in terms of sex and left or right ulnar nerve instability. CONCLUSIONS: Ulnar nerve instability correlated with age in children. Children aged <3 years had a low risk of ulnar nerve instability.

Mini approaches fasciotomy combined with vacuum sealing drainage for acute compartment syndrome caused by fractures in children.

PURPOSE: Acute compartment syndrome (ACS) is an urgent, critical condition that requires immediate fasciotomy once diagnosed. Traditionally, fasciotomy of the forearms and lower leg involves one or two long approaches. Our previous study demonstrated that mini approaches fasciotomy was an effective method to treat ACS. This study is aimed at further evaluating the limb functions and complications of mini approaches combined with vacuum sealing drainage (VSD) for treating ACS caused by fractures in the forearms and lower legs. METHODS: This was a retrospective cross-sectional study, and after applying the inclusion and exclusion criteria, we reviewed 126 children who underwent mini treatment approaches for ACS from Jan 2008 to Jan 2022. The selected patients were divided into two groups: group A (ACS group; 58 patients aged 7.77±3.45 years) and group B (ACS combined with VSD; 68 patients aged 7.17±3.55 years). Patients' clinical data were collected. The patients were followed up, and muscle function in the forearms and lower legs was evaluated. RESULTS: The overall incidence of lower legs and forearms ACS was 126/29642 (0.425%). The most common mechanisms of injury were fractures of the forearm (39/74, 52.7%), supracondylar humerus (31/74 41.9%), and elbow (4/74, 5.4%), while those for the lower legs were fractures of the proximal tibia (19/52, 36.5%), midshaft of tibia (25/52, 48.1%), and distal tibia (7/52, 13.5%). According to Flynn's assessment, no significant difference was observed between the two groups (p=0.151). However, the two groups showed significant differences in the hospitalization time (p=0.002) and incision infection rate (0.043). CONCLUSIONS: Mini approaches fasciotomy combined with VSD is an effective and safe method to treat ACS of the forearms and lower legs caused by fractures in children. This method involves a single-stage surgery and is associated with shorter hospitalization time and incision infection.

Magnetic resonance-enhanced high-resolution three-dimensional water-selective cartilage sequence visualization of hip vessels in children.

PURPOSE: Hip vessel examination provides key information on many hip-related pediatric diseases, and it has an important role in the evaluation of femoral head (FH) blood supply and diagnosis of avascular necrosis (AVN). The aim of this study was to investigate the feasibility of MR-enhanced high-resolution three-dimensional water-selective cartilage (3D-WATSc) sequence in visualizing the vessels of the hip joint in children. PATIENTS AND METHODS: Children with hip disease were randomly enrolled prospectively at our hospital from January 2021 to August 2022. We performed our institution's hip MRI protocol and enhanced high-resolution 3D-WATSc sequence. The 3D-WATSc images were reconstructed and analyzed, and images of the normal hip were categorized into grades 0-3. The abnormal hip images were compared with those of the normal side using the χ2 test. RESULTS: Twenty-four patients with unilateral hip abnormalities were included in this study. The cartilaginous vascular canal and ossification centre vessels of normal FHs were observed in 18 patients (75%) and met the grade 3 standard. An abnormal cartilaginous canal was observed in 16 patients (67%); meanwhile, 18 patients (75%) had abnormal extrachondral vessels. Comparison of high-resolution 3D-WATSc images with those of the normal side provided effective abnormal vascular information in 95.8% of patients. CONCLUSIONS: Enhanced high-resolution 3D-WATSc can visualize the blood vessels of the hip in children. This may provide a new method for the vascular study of various pediatric hip diseases.

Is conservative treatment a good choice for pediatric intervertebral disc calcification in children?

PURPOSE: Paediatric intervertebral disc calcification (PIDC) is a rare disease, and its aetiology remains unknown. This study aimed to analyse the characteristics and clinical outcomes of patients with PIDC. METHODS: After applying the exclusion and inclusion criteria, 159 children diagnosed with PIDC were analysed at our hospital between January 2010 and November 2020. Patients' demographic and clinical data were collected, such as sex, pain, duration time, physical examination, white blood cell count, erythrocyte sedimentation rate, C-reactive protein, and radiography, computed tomography, and magnetic resonance imaging findings. Patients were followed up for at least 6 months, and radiography or symptoms were evaluated. Fisher's exact test or χ2-test was used for statistical analyses. RESULTS: One hundred and fifty-nine patients were ultimately followed up with for about 12.5 ± 5.8 months. There were 103 male and 56 female, with an average age of 6.08 ± 2.62 years (2 months to 12 years). A total of 109 patients had only one PIDC, 29 patients had two PIDCs, and 21 patients had multiple PIDCs. Thirty patients were found incidentally and were asymptomatic. A total of 106 patients had neck torticollis. Sixteen patients had IDC herniations, fifteen patients had posterior longitudinal ligament calcification, two patients had anterior longitudinal ligament calcification, and 17 patients had herniation of the vertebral canal. All patients underwent conservative treatment, and none underwent surgery. All patients' symptoms resolved after either collar fixation or neck traction. CONCLUSION: PIDC can be treated conservatively, even when accompanied by herniation, longitudinal ligament calcification, or clinical neck symptoms. LEVEL OF EVIDENCE: IV.

A novel method of lateral closing wedge osteotomy for cubitus varus deformity in children.

BACKGROUND: Humeral osteotomy is the best method for treatment of severe cubitus varus in children. Many osteotomy methods have been developed in the past. In this study, we describe a novel corrective technique by applying the principles described by Paley involving lateral osteotomy using Kirschner wires (K-wires). Vertices of the osteotomy should be located at the center of rotation of angulation. The anatomical and mechanical axes can be corrected with precision. PATIENTS AND METHODS: In this retrospective study, 21 patients (17 male, 4 female) who fulfilled the study criteria and underwent lateral closing osteotomy for cubitus varus deformity from July 2015 to October 2017 were included into the study. The osteotomy line of all patients was designed according to Paley's principles. An isosceles triangle template was made according to the design preoperatively. The lateral osteotomy was made with the assistance of C-arm radiographs. The osteotomy was fixed by K-wires laterally. Patients were followed up, and elbows were evaluated by radiography and using the Mayo Elbow Performance Index (MEPI) score. RESULTS: The mean correction angle obtained was 32.33°±2.83°. According to the MEPI score assessment, 19 of the 21 patients had an excellent outcome and two had a good outcome. Two patients complained of conspicuous scars; however, no further cosmetic surgery was performed. The range of motion was 135.0° preoperatively and 133.7° postoperatively, showing no significant difference (p = 0.326). None showed evidence of neurovascular injury or complained of prominence of the lateral humerus. CONCLUSION: Paley's principles for correcting cubitus varus deformity in children are effective and reliable for treating such a condition. LEVEL OF EVIDENCE: Therapeutic IV.

Foreign body removal with the assistance of ultrasound guidance and methylene blue staining in children-a cohort study.

BACKGROUND: Soft tissue foreign bodies (FBs) are very commonly observed in paediatric emergency departments. Not all FBs can be removed effectively, even via open surgery and image intensifier guidance. In the current study, we evaluated the efficiency of FB removal with the assistance of ultrasound (US) and methylene blue (MB) staining. METHODS: We enrolled 80 patients at our clinical center between May 2016 and December 2020. Eleven patients were operated upon with the assistance of US guidance and MB and were defined as group A; the other 69 patients were defined as group B. For the patients in group A, US was first used to locate the FB; MB was then injected next to the FB. Open surgery was subsequently performed. For group B, the FBs were removed by conventional methods. The surgical outcomes were evaluated according to surgical duration, incision infection rates, radiograph exposure times, and FB residue rates. RESULTS: The average surgery time for group A was 0.35 ± 0.10 hours; the corresponding time was 0.49 ± 0.50 hours in group B and there was a significant difference between the groups (p = 0.032). The radiograph exposure times were 1.33 ± 0.34 in group A and 4.65 ± 1.81 times in group B (p = 0.021). CONCLUSIONS: This study demonstrates that assistance of US and MB staining is a more efficient approach compared with traditional methods for FB removal, and this surgical method can be used effectively for FB removal in children.

Retrospective analysis of traumatic triradiate cartilage injury in children.

BACKGROUND: To summarize and analyze the epidemiological characteristics, treatment and corresponding curative effect of triradiate cartilage injury(TCI) in children after trauma, to provide a theoretical basis for early diagnosis and improvement of treatment. METHODS: The TCI was classified according to Bucholz classification, and the final curative effect was evaluated with Harris Hip Score and imaging examination during follow-up. Finally, a comprehensive analysis was made by reviewing the cases in the literature combined with the patients in our hospital. RESULTS: A total of 15 cases (18 hips) of triradiate cartilage injuries were collected in our hospital. There was 1 hip with type I injury, nine hips with type II injury, two hips with type IV injury, one hip with type V injury and five hips with type VI injury. Among the 12 cases with complete follow-up, the bone bridge was found in or around the triradiate cartilage in 8 cases, early fusion of triradiate cartilage occurred in 5 patients, 3 cases had hip dysplasia, 4 cases had a subluxation of the femoral head, and HHS was excellent in 8 cases and good in 4 cases. CONCLUSION: The early diagnosis of TCI is still a difficult problem. Conservative treatment is often the first choice. The overall prognosis of acetabular fractures involving triradiate cartilage is poor. The formation of the bone bridge in triradiate cartilage usually indicates the possibility of premature closure, which may lead to severe complications of post-traumatic acetabular dysplasia and subluxation of the femoral head.

Are open surgery and total resection good choices for traumatic myositis ossificans in children?

BACKGROUND: Traumatic myositis ossificans is a self-limited, non-neoplastic, ectopic bone formation in the soft tissues caused by trauma. Conservative treatment is the mainstay of management. However, open surgery and complete resection should be considered in patients with limited joint function and constant pain. Herein, we retrospectively analyzed the outcome of open surgical resection in children with myositis ossificans (MO). METHODS: The data of patients diagnosed with MO between February 2010 and May 2019 were retrospectively analyzed. The clinical data included medical history, physical examination, and laboratory, imaging, and pathological findings. All patients underwent an open surgery and total resection. Radiography findings and joint function were evaluated. Patients with developing complications, such as recurrence and assessing joint function, were followed up. In total, 20 patients (sex, 15 male and 5 female patients; age, 8.1 ± 2.5 years) were included. RESULTS: MO was located around the elbow, wrist, proximal humerus, and thigh in 13, one, one, and five patients, respectively. All patients were followed up for > 12 months. Two patients had partial recurrence after surgery. One patient with forearm MO had poor elbow function (Broberg-Morrey score of 70). Nineteen patients had good functional outcomes according to the Broberg-Morrey and Cooney methods. CONCLUSION: Open surgical resection is an effective method for children with MO. The recurrence rate was low when the surgery was performed after the acute stage (1.5 months from disease presentation).

Risk factors for refracture of the femoral shaft in children after removal of external fixation.

BACKGROUND: External fixation is the primary treatment option in children for femoral shaft fractures, such as open femoral or multiple fractures. One complication is refracture, which is the biggest limitation of fixation devices. This study aims to investigate the risk factors associated with refracture after the removal of external fixation devices and decrease the frequency of refracture. MATERIALS AND METHODS: Retrospectively reviewed clinical data of 165 patients treated at our hospital for fresh femoral shaft fractures with external fixation between May 2009 and February 2018 were included in this study. Patients with pathological fractures, fractures of the femoral neck, fractures that were fixed using plates or elastic stable intramedullary nailing, and old fractures, as well as those who underwent postoperative femoral surgery were excluded. Potential risk factors included: patient age, gender, and weight, fracture sides, open or closed fracture, fracture sites, reduction methods, operation time, perioperative bleeding, number and diameter of the screws, and immobilization time. These factors were identified by univariate and logistic regression analyses. RESULTS: Femoral shaft refracture developed in 24 patients. Univariate analysis revealed that refracture was not statistically significantly associated with any of the above factors, except AO Pediatric Comprehensive Classification of Long Bone Fractures (PCCF) classification type 32-D/4.2 and L2/L3 ratio (L2, length of femur fixed by the two screws farthest from the fracture line; L3, the total length from the greater trochanter to the distal end of femur; P < 0.001 and P = 0.0141, respectively). Multivariate analysis showed that PCCF classification type 32-D/4.2 and L2/L3 ratio were also independent risk factors for femoral refracture. CONCLUSIONS: Femoral shaft refracture is relatively common in children treated with external fixation. Because of the limited number of cases in this study, we cautiously concluded that the PCCF classification type 32-D/4.2 and L2/L3 ratio were independent risk factors for femoral shaft refracture in these patients. LEVEL OF EVIDENCE: IV.

An Alternative to the Traditional Radiocapitellar Line for Pediatric Forearm Radiograph Assessment in Monteggia Fracture.

OBJECTIVE: To find a new reference for assessment of pediatric forearm radiographs besides the traditional RCL. METHODS: RCLs were drawn on the anteroposterior (AP) and lateral radiographs of 170 normal pediatric forearms. Three lines were drawn on each radiograph: the first was drawn along the longitudinal center of the radial neck (N-line); the second, along the radial shaft (S-line); and the third, through the midpoints of the proximal and distal radial physes (P-line). RESULTS: The P-line was least likely to miss the capitellum on both AP views and lateral views, and the P-line most frequently passed through the central third of the capitellum on both AP views and lateral views. CONCLUSIONS: Our proposed radiocapitellar P-line was found to be much more reliable in younger children than traditional RCLs.

Open Reduction of Neglected Supracondylar Humeral Fractures With Callus Formation in Children.

BACKGROUND: The standard treatment for supracondylar humeral fractures (SHFs) in children is closed reduction and percutaneous Kirschner (K)-wire fixation. In patients who present >14 days after injury and show callus formation, this procedure cannot be performed. There are 2 options in these cases: functional exercises with osteotomy performed at a later stage if cubitus varus is present, or immediate open reduction and percutaneous K-wire fixation. This study aimed to evaluate the outcomes of K-wire fixation through an anterior approach in children with neglected SHF and identify factors predicting the outcomes. METHODS: This retrospective study assessed the files of 32 children treated for neglected SHF at our hospital between June 2015 and May 2018. An incision was made along the anterior transverse groove of the elbow. The callus was removed, the fracture was reduced, and K-wire fixation was performed. The outcome evaluation included the radiological Baumann angle, pin fixation construct, carrying angles, and the functional outcome was Mayo Elbow Performance Score and Flynn criteria. Binary regression analysis compared the functional outcome as the dependent variable with age, time from injury to operation, operation time, and the amount of callus. RESULTS: The interval between injury and operation was 14 to 40 days (average, 22.4 d). Patients were followed for 12 to 36 months (average, 21.5 mo). Fracture healing took 5 to 8 weeks (average, 6.6 wk). No patient had a vascular injury or compartment syndrome. Twelve patients were intraoperatively assessed for radial and median nerve injury. No nerve repair was required. All nerve injuries recovered within 3 months. No iatrogenic ulnar nerve injury occurred. One patient had an infected incision. Binary regression analysis showed that the time elapsed between injury and operation (P=0.033) and Gartland type (P=0.008) were inversely correlated with outcomes; the longer the duration, the poorer the outcomes. CONCLUSIONS: The functional outcomes after open reduction and K-wire fixation through an anterior approach were poorer with longer time to surgery and Gartland type. LEVEL OF EVIDENCE: Level III.

Treatment of displaced radial neck fractures under ultrasonographic guidance in children.

PURPOSE: This study aimed to evaluate the feasibility of reduction under ultrasonographic (US) guidance with Kirschner wires (K-wires) and fixation with elastic stable intramedullary nails (ESINs) in the treatment of radial neck fractures (RNFs). METHODS: This retrospective study included 50 children treated for Judet types III and IV RNFs at our hospital from September 2015 to November 2018. Patients were divided into two groups: group A (without US) and group B (with US). Group A patients were treated using the Métaizeau technique; one K-wire was used for reduction under the guidance of X-ray fluoroscopy. Group B patients were treated using the same technique, but under the guidance of US. Post-operative radiographs, elbow function, and complications were analyzed. RESULTS: All patients were followed up over a period of 12 months. Five patients in group A had posterior interosseous nerve (PIN) injury, whereas no patient in group B had PIN injury (p = 0.016). The use of US guidance resulted in lower radiation exposure and shorter operation time. According to the Mayo Elbow Performance Index, there was no significant difference between the two groups (p = 0.814), including post-operative complications (radial head necrosis, fracture displacement, or stiffness). CONCLUSION: US guidance during surgery is feasible to treat Judet type III and IV RNFs. US guidance can significantly reduce X-ray radiation exposure and the risk of PIN injury.

CREB/Wnt10b mediates the effect of COX-2 on promoting BMP9-induced osteogenic differentiation via reducing adipogenic differentiation in mesenchymal stem cells.

Bone morphogenetic protein 9 (BMP9) is one of the most potent osteogenic factors, which may be a potential candidate for bone tissue engineering. However, the osteogenic capacity of BMP9 still need to be further enhanced. In this study, we determined the effect of Wnt10b on BMP9-induced osteogenic differentiation in mesenchymal stem cell (MSCs) and the possible mechanism underlying this process. We introduced the polymerase chain reaction (PCR), Western blot analysis, histochemical stain, ectopic bone formation, and microcomputed tomography analysis to evaluate the effect of Wnt10b on BMP9-induced osteogenic differentiation. Meanwhile, PCR, Western blot analysis, chromatin immunoprecipitation, and immunoprecipitation were used to analyze the possible relationship between BMP9 and Wnt10b. We found that BMP9 upregulates Wnt10b in C3H10T1/2 cells. Wnt10b increases the osteogenic markers and bone formation induced by BMP9 in C3H10T1/2 cells, and silencing Wnt10b decreases these effects of BMP9. Meanwhile, Wnt10b enhances the level of phosphorylated Smad1/5/8 (p-Smad1/5/8) induced by BMP9, which can be reduced by silencing Wnt10b. On the contrary, Wnt10b inhibits adipogenic markers induced by BMP9, which can be decreased by silencing Wnt10b. Further analysis indicated that BMP9 upregulates cyclooxygenase-2 (COX-2) and phosphorylation of cAMP-responsive element binding (p-CREB) simultaneously. COX-2 potentiates the effect of BMP9 on increasing p-CREB and Wnt10b, while silencing COX-2 decreases these effects. p-CREB interacts with p-Smad1/5/8 to bind the promoter of Wnt10b in C3H10T1/2 cells. Our findings suggested that Wnt10b can promote BMP9-induced osteogenic differentiation in MSCs, which may be mediated through enhancing BMP/Smad signal and reducing adipogenic differentiation; BMP9 may upregulate Wnt10b via the COX-2/p-CREB-dependent manner.

Wnt11 promotes BMP9-induced osteogenic differentiation through BMPs/Smads and p38 MAPK in mesenchymal stem cells.

Bone morphogenetic protein 9 (BMP9), as one of the most potent osteogenic factors, is a promising cytokine for bone tissue engineering. Wnt11 can regulate the development of the skeletal system and is related to high bone mass syndrome. However, the effect of Wnt11 on BMP9-induced osteogenic differentiation remains unknown. In this study, we investigated the relationship between Wnt11- and BMP9-induced osteogenic differentiation in mesenchymal stem cells (MSCs). We recapitulated the osteogenic potential of BMP9 in C3H10T1/2 cells. The messenger RNA expression of Wnt11 is detectable in the available progenitor cells, and BMP9 can obviously increase the protein level of Wnt11 in these cells. Exogenous Wnt11 potentiates the effect of BMP9 on increasing alkaline phosphatase (ALP) activities, the expression of osteopontin (OPN), and Runt-related transcription factor 2 (Runx2), so does matrix mineralization in C3H10T1/2 cells. Although Wnt11 cannot increase the BMP9-induced ectopic bone formation, it can increase the bone density induced by BMP9 apparently. Wnt11 increases the level of p-Smad1/5/8, as well as p-p38. Meanwhile, Wnt11 promotes the effect of BMP9 on increasing the levels of p-Smad1/5/8 and p-p38. Inhibition of p38 decreases the BMP9-induced ALP activities, the expression of OPN, and the mineralization in C3H10T1/2 cells. However, all of these effects of the p38 inhibitor on BMP9-induced osteogenic markers can be almost reversed by the overexpression of Wnt11. Our findings suggested that Wnt11 can enhance the osteogenic potential of BMP9 in MSCs, and this effect may be partly mediated through enhancing BMPs/Smads and the p38 MAPK signal, which was induced by BMP9.

BMP9/COX-2 axial mediates high phosphate-induced calcification in vascular smooth muscle cells via Wnt/ß-catenin pathway.

Vascular calcification is a notable risk factor for cardiovascular system. High phosphate can induce calcification in vascular smooth muscle cells (VSMCs), but the detail mechanism underlying this process remains unclear. In the present study, we determined the relationship between high phosphate and bone morphogenetic protein 9 (BMP9) in VSMCs, the effect of BMP9 on calcification in VSMCs and the effect of COX-2 on BMP9 induced calcification in VSMCs, as well as the possible mechanism underlying this biological process. We found that high phosphate obviously up-regulates the expression of BMP9 in VSMCs. Over-expression of BMP9 decreases the level of alpha-smooth muscle cell actin (α-SMA) apparently, but increases the level of Runx-2, Dlx-5, and ALP in VSMCs. Meanwhile, BMP9 increases the level of OPN and OCN, promotes mineralization in VSMCs and induces calcification in thoracic aorta. High phosphate and over-expression of BMP9 increases the level of COX-2. Over-expression of COX-2 enhances the inhibitory effect of BMP9 on α-SAM and increases the level of OPN and OCN induced by BMP9. However, inhibition of COX-2 decreases the BMP9-induced calcification in VSMCs and thoracic aorta. For mechanism, we found that high phosphate or BMP9 increases the level of ß-catenin and p-GSK3ß in VSMCs, but no substantial effect on GSK3ß. However, COX-2 inhibitor decreases the expression of ß-catenin induced by BMP9. Our findings indicated that BMP9 is involved in the phosphate-induced calcification in VSMCs and COX-2 partly mediates the BMP9-induced calcification in VSMCs through activating Wnt/ß-catenin pathway.

Reversibly immortalized human umbilical cord-derived mesenchymal stem cells (UC-MSCs) are responsive to BMP9-induced osteogenic and adipogenic differentiation.

Human mesenchymal stem cells (MSCs) are a heterogeneous subset of nonhematopoietic multipotent stromal stem cells and can differentiate into mesodermal lineage, such as adipocytes, osteocytes, and chondrocytes, as well as ectodermal and endodermal lineages. Human umbilical cord (UC) is one of the most promising sources of MSCs. However, the molecular and cellular characteristics of UC-derived MSCs (UC-MSCs) require extensive investigations, which are hampered by the limited lifespan and the diminished potency over passages. Here, we used the piggyBac transposon-based simian virus 40 T antigen (SV40T) immortalization system and effectively immortalized UC-MSCs, yielding the iUC-MSCs. A vast majority of the immortalized lines are positive for MSC markers but not for hematopoietic markers. The immortalization phenotype of the iUC-MSCs can be effectively reversed by flippase recombinase-induced the removal of SV40T antigen. While possessing long-term proliferation capability, the iUC-MSCs are not tumorigenic in vivo. Upon bone morphogenetic protein 9 (BMP9) stimulation, the iUC-MSC cells effectively differentiate into osteogenic, chondrogenic, and adipogenic lineages both in vitro and in vivo, which is indistinguishable from that of primary UC-MSCs, indicating that the immortalized UC-MSCs possess the characteristics similar to that of their primary counterparts and retain trilineage differentiation potential upon BMP9 stimulation. Therefore, the engineered iUC-MSCs should be a valuable alternative cell source for studying UC-MSC biology and their potential utilities in immunotherapies and regenerative medicine.

Internal Fixation With Absorbable Rods for the Treatment of Displaced Radial Neck Fractures in Children.

BACKGROUND: The treatment of radial neck fractures with complete displacement or severe displacement and an angle of >30 degrees is controversial. The currently used methods, including the Metaizeau technique, are associated with drawbacks such as imperfect reduction, epiphyseal damage, and delayed functional recovery. To overcome these drawbacks, we used absorbable rod fixation followed by early functional training for the treatment of displaced radial neck fractures in children. METHODS: In this study, 68 patients (age, 4 to 12 y; average, 8.4 y; average angle, 58 degrees; average displacement, 53%) with radial neck fractures with Salter-Harris grades II to IV underwent lateral elbow open reduction and absorbable rod fixation. At 3 weeks postoperatively, the patients' plaster casts were removed, and functional training was started. RESULTS: Anatomic reduction was achieved in all patients. We followed-up 68 patients for 6 months to 4 years (average, 41 mo). No cases of radial nerve injury, radial bone necrosis, myositis ossificans, and postoperative infection were observed. The functional recovery was "excellent" in 43 patients, "good" in 13 patients, "average" in 12 patients, and "bad" in 0 patients, according to the Morrey evaluation standard. CONCLUSION: Open reduction with absorbable rod fixation for the treatment of displaced radial neck fractures in children was feasible and was a choice in children. LEVEL OF EVIDENCE: Therapeutic II.

Visualization of the wrist ganglion capsule by methylene blue staining as an aid for complete resection in children.

PURPOSE: To evaluate the effectiveness of methylene blue staining during ganglion resection in children, to assess ganglion resection and minimize recurrence. METHODS: From August 2007 to March 2011, 36 children with dorsal or volar wrist ganglions with an average size of 2 cm (range, 1-4 cm), including 5 recurrent cases, underwent resection performed with intraoperative methylene blue marking of the cyst wall. RESULTS: We found recurrence in one patient after 2 years; no obvious complications were observed in any patient. CONCLUSIONS: Methylene blue staining of the ganglion during resection may be helpful for achieving complete resection. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.

[Analysis on traditional Chinese medicine prescriptions treating cancer based on traditional Chinese medicine inheritance assistance system and discovery of new prescriptions].

Malignant tumor is one of the main causes for death in the world at present as well as a major disease seriously harming human health and life and restricting the social and economic development. There are many kinds of reports about traditional Chinese medicine patent prescriptions, empirical prescriptions and self-made prescriptions treating cancer, and prescription rules were often analyzed based on medication frequency. Such methods were applicable for discovering dominant experience but hard to have an innovative discovery and knowledge. In this paper, based on the traditional Chinese medicine inheritance assistance system, the software integration of mutual information improvement method, complex system entropy clustering and unsupervised entropy-level clustering data mining methods was adopted to analyze the rules of traditional Chinese medicine prescriptions for cancer. Totally 114 prescriptions were selected, the frequency of herbs in prescription was determined, and 85 core combinations and 13 new prescriptions were indentified. The traditional Chinese medicine inheritance assistance system, as a valuable traditional Chinese medicine research-supporting tool, can be used to record, manage, inquire and analyze prescription data.