Arthroscopic debridement and reduction is an effective procedure for failed closed reduction in young children with developmental dislocation of the hip.

PURPOSE: To assess the efficacy of arthroscopic debridement and reduction through two medial portals for the treatment of developmental dislocation of the hip (DDH) with failure of initial closed reduction and to explore key pathological structures obstructing reduction. METHODS: Forty-eight children with 58 irreducible dislocated hips treated by arthroscopic reduction between January 2017 and December 2020 were retrospectively evaluated. Arthroscopic reduction was performed via two medial portals located in the superior and inferior adductor longus. All intra-articular obstacles were eliminated via arthroscopy, followed by manual reduction and spica cast immobilization. The surgical duration, extent of improvement in the safe zone, and extent of secondary surgical treatment were noted. All the children were followed up for > 24 months. Hip function and radiographic outcomes were evaluated. RESULTS: All 58 hips showed safe zone improvement and concentric reduction after arthroscopic debridement. Hypertrophic ligamentum teres and thickened pulvinars were detected and resected in all hips. Constrictive capsules preventing reduction were observed in 15 hips, which needed to be further released. No inverted labrum was observed. Secondary surgery was performed in four hips with redislocation and seven hips with subluxation during follow-up. The remaining 47 hips (81.03%) maintained their reduction at the last follow-up. Excellent and good clinical outcomes were achieved in 95.74% of patients according to McKay's criteria. Two hips, three hips, and one hip were diagnosed with grade I, II, and III osteonecrosis of the femoral head, respectively. CONCLUSION: This study demonstrated that arthroscopic debridement and reduction is a safe and feasible choice for treating irreducible DDH.

Arthroscopically assisted closed reduction for displaced lateral humeral condyle fractures over 4 mm in children.

INTRODUCTION: Lateral humeral condyle fractures (LHCFs) are the most common intra-articular fracture occurring at the elbow in children. Conventional treatment for displaced pediatric LHCFs is open reduction and percutaneous pinning, and few studies have regarded the efficacy of arthroscopic-assisted techniques. We aimed to evaluate the efficacy of anatomic reduction via elbow arthroscopy for pediatric humeral lateral condyle fractures with displacements >4 mm. METHODS: A total of 32 children with LHCFs featuring displacements >4 mm were enrolled in this retrospective study. Arthroscopically assisted reduction was performed as the primary treatment approach. For simple displaced fractures, arthroscopically assisted reduction was directly employed with intermittent intra-articular irrigation. For fractures with distal fragment rotation, the rotated fragments were firstly realigned into a simple displaced position under fluoroscopy before proceeding with arthroscopy. The success rate of arthroscopically assisted reduction and clinical outcomes at the latest follow-up were assessed, and complications related to the procedure were monitored. RESULTS: Twenty-nine of 32 (90.62 %) enrolled cases were successfully treated with arthroscopically assisted reduction. Failure cases were attributed to soft tissue swelling, which hindered the manipulation of the fracture fragments for reduction or fixation. We subsequently adapted the surgical procedure, resulting in a significant increase in the success of arthroscopically assisted reduction, rising from 71.43 % to 96 %. Among the 29 successfully treated cases, excellent functional outcomes were observed in 18 cases, and 11 cases showed good outcomes. Regarding the carrying angle outcomes, 28 patients achieved excellent results, with one patient having a good outcome. The most frequent radiographic finding after surgery was lateral spur formation without further negative effects. Only one case of superficial infection occurred, promptly healing with topical management. No significant complications such as neurovascular injury or compartment syndrome were observed. CONCLUSION: Arthroscopically assisted anatomic reduction provides a promising alternative to open reduction for LHCFs with displacements exceeding 4 mm, offering direct visualization of the articular surface and minimizing soft tissue dissection.

Weak Fault Feature Extraction of Rolling Bearings Based on Adaptive Variational Modal Decomposition and Multiscale Fuzzy Entropy.

The working environment of rotating machines is complex, and their key components are prone to failure. The early fault diagnosis of rolling bearings is of great significance; however, extracting the single scale fault feature of the early weak fault of rolling bearings is not enough to fully characterize the fault feature information of a weak signal. Therefore, aiming at the problem that the early fault feature information of rolling bearings in a complex environment is weak and the important parameters of Variational Modal Decomposition (VMD) depend on engineering experience, a fault feature extraction method based on the combination of Adaptive Variational Modal Decomposition (AVMD) and optimized Multiscale Fuzzy Entropy (MFE) is proposed in this study. Firstly, the correlation coefficient is used to calculate the correlation between the modal components decomposed by VMD and the original signal, and the threshold of the correlation coefficient is set to optimize the selection of the modal number K. Secondly, taking Skewness (Ske) as the objective function, the parameters of MFE embedding dimension M, scale factor S and time delay T are optimized by the Particle Swarm Optimization (PSO) algorithm. Using optimized MFE to calculate the modal components obtained by AVMD, the MFE feature vector of each frequency band is obtained, and the MFE feature set is constructed. Finally, the simulation signals are used to verify the effectiveness of the Adaptive Variational Modal Decomposition, and the Drivetrain Dynamics Simulator (DDS) are used to complete the comparison test between the proposed method and the traditional method. The experimental results show that this method can effectively extract the fault features of rolling bearings in multiple frequency bands, characterize more weak fault information, and has higher fault diagnosis accuracy.

A Comparative Study on Closed Reduction vs. Open Reduction Techniques in the Surgical Treatment of Rotated Lateral Condyle Fractures of the Distal Humerus in Children.

Objective: The best approach between closed reduction and open reduction in the treatment of total displaced and rotated LCFs is still being debated. This study aimed to comparatively evaluate the clinical outcomes and complications of closed reduction vs. open reduction in the treatment of displaced and rotated lateral condyle fractures in children. Methods: We retrospectively evaluated 46 children who underwent surgical treatment for totally displaced and rotated lateral condyle fractures. Thirty-one children underwent open reduction and percutaneous pinning (ORPP). Ten children underwent closed reduction and percutaneous pinning (CRPP). Five children were changed to ORPP procedures because of the failure of closed reduction attempts. Clinical outcomes and complications in the groups were compared. Results: Among three groups, no significant differences were found in demographic variables, and no differences were detected in the incidence of postoperative complications and clinical parameters. The ORPP group had the shortest surgical duration of the three groups (p < 0.005). Patients in CRPP group had faster fracture healing than the patients who underwent open reduction procedures. However, the success of CRPP seemed to be dependent on the earlier surgical intervention. Conclusion: ORPP is still the first-line treatment for the totally displaced and rotated lateral condyle fractures because of its direct visualization of the joint surface and easy-to-accomplish characteristics. In addition, CRPP may be a feasible option for the treatment of this type of fractures because of it is less invasive and potentially minimizes complications. However, the technical difficulties of CRPP must be taken into account.

Closed Reduction and Percutaneous Pinning in the Treatment of Humeral Distal Metaphyseal-Diaphyseal Junction Fractures in Children: A Technique Note and Preliminary Results.

Objective: The metaphyseal-diaphyseal junction (MDJ) fracture is an uncommon but problematic type of fracture occurring at the distal humerus in children. Closed reduction and fixation are challenging and may not be possible with the conventional reduction maneuver utilized in supracondylar fractures. The purpose of this study was to evaluate a novel closed reduction and percutaneous pinning (CRPP) technique for the treatment of these fractures. Methods: We retrospectively evaluated 14 children (8 boys and 6 girls) who underwent closed reduction and percutaneous fixation for the treatment of MDJ fractures. Six children who underwent treatment with a novel CRPP technique were enrolled as Group A. Eight children underwent the conventional reduction maneuver utilized in supracondylar fracture and were enrolled as Group B. Clinical and radiographic outcomes in the two groups were then compared. Results: In Group A, all six MDJ fractures were treated successfully with the novel CRPP technique without the need for open procedures or re-operation. No complications such as pin-site infection or iatrogenic nerve injury were found in this group. In group B, five of the eight fractures were treated successfully with the conventional CRPP technique; three fractures needed open reduction, and one of them had further surgery because of the loss of fixation. Children with successful CRPP in each group were included to compare the efficacy of the novel CRPP technique. The average duration of the surgery in Group A was significantly shorter than that in Group B (p < 0.001). At last follow-up, both groups obtained satisfactory clinical and radiographic outcomes. Conclusion: MDJ fractures can be reduced successfully and fixed stably via a novel CRPP technique, and laborious and frustrating attempts at closed reduction and further open reduction can be avoided.

Arthroscopically Assisted Cannulated Screw Fixation for Treating Type III Tibial Intercondylar Eminence Fractures: A Short-Term Retrospective Controlled Study.

Background: This study presents the clinical results from 22 children who underwent minimally invasive arthroscopically assisted screw fixation for the treatment of intercondylar eminence fractures. Methods: We retrospectively analyzed the clinical data of 22 children (aged 7.5 to 13.5 years) with type III tibial intercondylar eminence fractures who were treated in our department from March 2007 to September 2019. According to the type of operation, the patients were divided into two groups: group A (n = 12) received arthroscopically assisted cannulated screw fixation, and group B (n = 10) received open reduction and cannulated screw internal fixation. Radiography scans, Lysholm scores, International Knee Documentation Committee (IKDC) 2,000 subjective scores, Tegner scores, range of motion (ROM) of the knee, the anterior drawer test (ADT), the Lachman test, and the pivot-shift test were used to evaluate the clinical efficacy. Results: All 22 children were evaluated over a 12 to 58 month follow-up period (mean: 27.5 months). At the final exam, group A was significantly superior to group B in Lysholm scores (93.33 ± 3.55 vs. 86.20 ± 4.52), IKDC scores (92.06 ± 3.55 vs. 86.07 ± 5.81), and Tegner scores (7.75 ± 0.87 vs. 6.40 ± 0.52) and presented shorter operative times (25.42 ± 3.97 vs. 35.00 ± 5.27). The differences were statistically significant (P < 0.05). All the incisions healed primarily. No complications, such as fracture fragment displacement, delayed epiphyseal growth, or knee joint dysfunction, were observed. The drawer test, Lachman test, and pivot-shift test were negative for all patients. Conclusions: Arthroscopically assisted cannulated screw fixation is effective and safe for the treatment of tibial intercondylar eminence fractures, providing excellent stability and quick recovery of joint function.

Efficacy of closed reduction for developmental dysplasia of the hip: midterm outcomes and risk factors associated with treatment failure and avascular necrosis.

BACKGROUND: The purpose of this study was to evaluate the efficacy of closed reduction (CR) in the treatment of developmental dysplasia of the hip (DDH) and to investigate risk factors associated with CR failure and avascular necrosis (AVN) occurrence in follow-ups. METHODS: The study retrospectively included 110 patients and 138 hips with DDH diagnosis that underwent closed reduction between February 2012 and November 2015 in our single tertiary medical institution. The failure rate of CR and the underlying risk factors were evaluated. Meanwhile, the incidence of AVN and the related risk factors among the successful CR cases were assessed. RESULTS: The overall failure rate of DDH treated by CR in the present study was 31.16% (43/138). Risk factors for the CR failure were older age at the time of CR (≥ 18.35 month), large medical interval before CR (≥ 35.35 mm), and severer dislocation of the affected hip (IDHI grades III and IV). The incidence of AVN was 8.33% (6/72) in patients with successful CR at the last follow-up. No significant risk factors had been established in the present study that associated with the AVN occurrence. CONCLUSIONS: For the treatment of DDH with CR, patients with younger age might achieve better outcomes; early diagnosis and early treatment might be the key point in the DDH treatment.

Ultrasonography-guided closed reduction in the treatment of displaced transphyseal fracture of the distal humerus.

BACKGROUND: To evaluate the clinical and radiographic outcomes of ultrasonography-guided closed reduction in the treatment of displaced transphyseal fracture of the distal humerus (TFDH). METHODS: Twenty-seven patients with displaced TFDH were successfully treated by the ultrasonography-guided closed reduction during January 2012 to December 2016 and were retrospectively reviewed. After the mean follow-up of 34.88 months, the clinical and radiographic outcomes of patients were evaluated. The cubitus varus of the affected elbows was also assessed at the latest follow-up. RESULTS: The successful rate of ultrasonography-guided closed reduction in the treatment of displaced TFDH was 84% (27/32). The twenty-seven patients with successful reduction were included for the following analysis. There were 20 males and 7 females included in the study, and the mean age at treatment was 15.39 ± 3.10 months; seventeen fractures occurred in the right side elbow and ten in the left side. At the last follow-up, there were significant decreases in the elbow flexion (3°, P = 0.027) and range of motion (5°, P = 0.003) between the injured and uninjured elbow, respectively, whereas no difference in elbow extension was detected (P = 0.110). Flynn's criteria assessment showed that all the patients achieved excellent or good outcomes both in the functional and cosmetic categories. The clinical and radiographic carrying angles at the last follow-up were 11.67 ± 3.11° and 10.46 ± 3.88°, respectively. And the incidence of cubitus varus after treatment was 7.4% at the last follow-up. CONCLUSION: The ultrasonography-guided closed reduction in the treatment of displaced TFDH is an effective procedure; the adequate fracture reduction can be acquired with the advantages of real-time, non-radioactive, and simple utilization. With the percutaneous pining fixation, satisfactory clinical and radiographic outcomes can be achieved with a low incidence of postoperative cubitus varus.

Older age and multi-joint external fixator are two risk factors of complications in ulnar lengthening in children with hereditary multiple exostosis.

OBJECTIVES: Hereditary multiple exostosis (HME) often involves forearm deformities. The aim of this study was to present the clinical results of 37 children who underwent ulnar lengthening with two different types of unilateral external fixators and to investigate the risk factors of complications. METHODS: We evaluated 37 children with forearm deformities caused by HME treated in our hospital from January 2008 to July 2019. The surgical procedures included resection of exostosis, osteotomy of the ulna, and gradual lengthening of the ulna with a unilateral external fixator. According to the type of fixator they received, the children were divided into two groups: group A received monorail fixators and group B received multi-joint fixators. Radiographic and functional parameters were assessed. Complications were recorded. RESULTS: All patients were followed-up for an average of 4.6 years (3.0 to 6.5). In both group A and group B, the ulna shortening (US), radial articular angle (RAA), carpal slip (CS), elbow flexion, forearm pronation, supination, and Mayo Elbow Performance Score (MEPS) values improved significantly from preoperatively to postoperatively (p < 0.05). However, the ulnar deviation was observed in 4 cases in group B and no cases in group A. According to logistic regression, the difference was only related to age (p < 0.05) and the type of external fixator (p < 0.05). CONCLUSIONS: Ulnar lengthening with unilateral external fixation is a safe and effective procedure for the treatment of HME. Regarding complications, deviation of the ulna axis was more likely to occur in older children with multi-joint external fixators.

Treatment of rigid congenital clubfoot with Ilizarov technique in older children

Objective: To investigate the effectiveness of Ilizarov technique in treatment of rigid congenital clubfoot in older children. Methods: A clinical data of 55 patients (69 feet) with rigid congenital clubfoot (Diméglio grade Ⅳ) between September 2005 and September 2015 were retrospectively analyzed. There were 33 boys and 22 girls with an average age of 11 years (range, 6-14 years). There were 41 cases of unilateral clubfoot and 14 cases of bilateral clubfeet. The degree of foot deformity was rated as fair in 24 feet and as poor in 45 feet according to International Clubfoot Study Group (ICFSG) score before operation. Sixty-nine feet were treated by Ilizarov external fixator combined with limited soft tissue release, and 21 feet were combined with individualized V-shaped osteotomies. Results: All patients were followed up 2-10 years ( mean, 4.2 years). The incisions healed well after operation. Five cases of needle tract infection occurred and were cured by local dressing change. The effectiveness was excellent in 39 feet, good in 21 feet, and fair in 9 feet according to ICFSG score, with the excellent and good rate of 87.0%. During the follow-up, X-ray films showed that no blood supply disorder or necrosis of talus, scaphoid, cuneiform, metatarsal, calcaneus, and cuboid occurred. No osteomyelitis occurred. Conclusion: Ilizarov technique combined with limited soft tissue release or V-shaped osteotomy for the older children with rigid congenital clubfeet is safe and can obtain significant orthopedic effectiveness.

Clinical significance of imaging findings for atlantoaxial rotatory subluxation in children

Background/aim: This study evaluated the usefulness of measuring the atlantodental interval (ADI) and lateral atlantodental spaces (LADSs) by retrospectively analyzing the imaging data of children of various ages with and without atlantoaxial rotatory subluxation (AARS). Materials and methods: The data of 495 children who underwent cranial computed tomography were collected. Among these children, 255 children were clinically diagnosed with AARS while 240 children were not. ADI and LADS values were measured. Results: The difference in mean ADI between children with and without AARS in all age groups was statistically significant (t-test, all P < 0.05). In children without AARS, the 95% reference range for ADI was <3.2 mm. The difference in the variance of bilateral lateral atlantodental spaces (VBLADSs) between children with and without AARS in all age groups was statistically significant (rank-sum test, all P < 0.05), with a 95% reference range of 0­2.20 mm (D-test). Conclusion: The ADI is a well-known and frequently used parameter and is not new, but there is little research about this in China and here we confirm its application in Chinese children. The LADS is not a frequently used parameter, but it does not significantly differ. The VBLADS parameter is new and significant in this manuscript. We concluded that VBLADSs of >2.2 mm are useful indicators for the diagnosis of AARS in patients ≤14 years old. Finally, it can be concluded that ADI of ≥3.2 mm and VBLADS of >2.2 mm are useful indicators for the diagnosis of AARS in patients ≤14 years old. Widened LADSs would not be helpful in the diagnosis of AARS in children.

Percutaneous autologous bone marrow transplantation for the treatment of delayed union of limb bone in children.

BACKGROUND AND PURPOSE: Percutaneous autologous bone marrow transplantation (PABMT) is a minimally invasive therapeutic strategy for the treatment of delayed bone union in adults, which has been confirmed by many studies. However, there is no report on PABMT application in pediatric orthopedic surgery. The aim of this article was to analyze the therapeutic effect of PABMT in children with delayed union of limb bone and its influence in relation to delayed bone union therapy, transplantation period, patients' sex, fracture location, and fracture fixation. METHODS: In this study, 53 patients (aged 3-16 years, with an average age of 6.7 years) with delayed union of long bone (20 femurs, 12 tibiae, 10 humeri, 5 radiuses, 5 ulnas, and 1 fibula) were treated using PABMT. Clinical examination and X-ray were integrated to evaluate the therapeutic effect. RESULTS: All 53 patients were followed up for 2-6 years (average time, 3.5 years). Of the 53 patients, 47 (88.7%) were healed, whereas the other 6 (11.3%) were not, and were subsequently treated by autologous bone grafting. In 30 patients who received their first PABMT treatment 6-8 months after fixation, the clinical cure rate, operation times, and healing time were 83.3%, 5.8±0.5 months, and 2.5±0.6, respectively. In the other 23 patients, whose first PABMT treatments were started within 4 to 6 months after fixation, the clinical cure rate, operation times, and healing time were 95.7% (P=0.167), 3.2±0.3 months (P=0.001), and 1.3±0.6 (P=0.001), respectively. The patients' sex, fracture location, and fracture fixation did not have statistical influence on the clinical efficacy. CONCLUSION: PABMT is a minimally invasive and effective strategy for the treatment of delayed union of limb bone in children. The early surgical treatment facilitates the fracture healing, reduces the number of transplantation, and shortens the course of treatment.

A poly(lactide-co-glycolide) film loaded with abundant bone morphogenetic protein-2: A substrate-promoting osteoblast attachment, proliferation, and differentiation in bone tissue engineering.

We explored a novel biodegradable poly(lactide-co-glycolide) (PLGA) film loaded with over 80 wt % bone morphogenetic protein (BMP)-2, which was regarded as a substrate-promoting osteoblast attachment, proliferation, and differentiation for application of bone tissue engineering. Using phospholipid as a surfactant, BMP-2 was modified as a complex (PBC) for dispersing in PLGA/dichloromethane solution. The PLGA film loaded with BMP-2 and phospholipid complex (PBC-PF) showed rough and draped morphology with high entrapment efficiency exceeding 80% and good hydrophilicity, respectively. The in vitro release study of BMP-2 showed that about 50% BMP-2 was slowly and continuously released from PBC-PF within 5 weeks and had a short initial burst release only in the last 1.5 days, which was better than serious burst release of PLGA film loaded with pure BMP-2 without phospholipid (BMP-PF) as control. By comparison with other PLGA films and tissue culture plates, it was confirmed that PBC-PF significantly promoted the attachment, proliferation, and differentiation of osteoblasts with higher entrapment efficiency and better sustained release. These advantages illustrated that PBC-PF could be a potential substrate providing long-term requisite growth factors for osteoblasts, which might be applied in bone tissue engineering.

[Effects of Plasmid Fibroblast Growth Factor-2 Magnetic Chitosan Gelatin Microspheres on Proliferation and Differentiation of Mesenchymal Stem Cells].

The purpose of this study is to investigate the effect of superparamagnetic chitosan FGF-2 gelatin microspheres (SPCFGM) on the proliferation and differentiation of mouse mesenchymal stem cells. The superparamagnetic iron oxide chitosan nanoparticles (SPIOCNs) were synthesized by means of chemical co-precipitation, combined with FGF-2. Then The SPCFGM and superparamagnetic chitosan gelatin microspheres (SPCGM) were prepared by means of crosslinking-emulsion. The properties of SPCFGM and SPIONs were measured by laser diffraction particle size analyser and transmisson electron microscopy. The SPCFGM were measured for drug loading capacity, encapsulation efficiency and release pharmaceutical properties in vitro. The C3H10 cells were grouped according to the different ingredients being added to the culture medium: SPCFGM group, SPCGM group and DMEM as control group. Cell apoptosis was analyzed by DAPI staining. The protein expression level of FGF-2 was determined by Western blot. The proliferation activity and cell cycle phase of C3H10 were examined by CCK8 and flow cytometry. The results demonstrated that both of the SPIOCNs and SPCFGM were exhibited structure of spherical crystallization with a diameter of (25 ± 9) nm and (140 ± 12) µm, respectively. There were no apoptosis cells in the three group cells. Both the protein expression level of FGF-2 and cell proliferation activity increased significantly in the SPCFGM group cells (P < 0.05). The SPCFGM is successfully constructed and it can controlled-release FGF-2, remained the biological activity of FGF-2, which can promote proliferation activity of C3H10 cells, and are non-toxic to the cell.

[Ectopic bone formation of bone marrow mesenchymal stem cells with gene transfer of human bone morphogenetic protein-9 gene in rabbit].

OBJECTIVE: To investigate the method combining hBMP-9 gene therapy with tissue-engineering techniques to improve osteogenesis in an ectopic bone formation model in rabbits. METHODS: Rabbit marrow MSCs were transferred with BMP-9 gene by cationic liposome, and then were subjected to a series tests including fluorescent microscope, Flow cytometer (FCM), ALP activity quantitative assay and Von Kossa's calcium nodus staninig; MSCs transfected with BMP-9 gene successfully were seeded onto scaffolds of polylactide-co-glycolide (PLGA). Cell-matrix interactions were observed with fluorescent microscopy and scanning electronic microscopy. The tissue-engineered bones with MSCs seeded on PLGA were further subcutaneously implanted into rabbits. The implants were evaluated with histological staining at 4 and 8 weeks after surgery. RESULTS: The gene transfer efficiency of MSCs transfected with BMP-9 gene was 34.15%, which was measured by FCM. The ALP activity of MSCs with BMP-9 gene transfer was higher than that of non-transfered cells (P < 0.01). The calcium nodus formation of MSCs was enhanced by the gene modification of BMP-9 gene. MSCs seeded onto PLGA showed high level of cell proliferation, and efficient synthesis of cell matrix was observed with, scanning electronic microscopy. In the ectopic bone formation model, new bone area was also significantly improved by BMP-9 gene modified MSCs seeded on PLGA (P < 0.05). CONCLUSION: hBMP-9 gene modified MSCs could enhance ectopic new bone formation in rabbits. These results indicated that the strategy combining BMP-9 gene modified MSCs with PLGA might be suitable for bone tissue engineering applications.