A novel intraoperative acetabular reaming center locating method in total hip arthroplasty for Crowe type IV developmental dysplasia of the hip: a retrospective cohort study.

PURPOSE: Although the principles of hip reconstruction are consistent, due to lack of reliable anatomical landmarks, how to decide the acetabular cup reaming centre intraoperatively in Crowe IV patients with developmental dysplasia of the hip (DDH) remains unclear. This study aims to address this question. METHODS: Fifty-eight Crowe IV patients were enrolled from 2017 to 2019. By examining our previous clinical data, we analyzed the anatomical morphology of Crowe IV acetabulum and proposed a method of locating intraoperative reaming centering for implantation of a standard-sized acetabular cup, which is the upper two thirds of the posterior border of the true acetabulum. All patients included in this study were reamed according to this method. The average postoperative follow-up was 4.1 years (3-5 years). The position of the centre of rotation (COR), cup coverage (CC), and optimal range of joint motion (ROM) were examined by 3D computer simulation measurement. Postoperative complications and hip Harris score were collected and analyzed. RESULTS: The morphology of the type IV DDH true acetabulum was mostly triangular. The intraoperative reaming centre were centered on the upper two thirds of the posterior border of the true acetabulum. The postoperative 3D CC was 80.20% ± 7.63% (64.68-90.24%, 44-48-mm cup size). The patients' mean Harris score improved from 39.7 ± 20.4 preoperatively to 91.5 ± 8.12 at the last follow-up. CONCLUSION: Our study demonstrated that satisfactory CC and clinical results could be achieved by implanting a standard-sized cup with the reaming centre on the upper two thirds of the posterior border of the true acetabulum.

A New Method to Predict Postoperative Stem Anteversion in Total Hip Arthroplasty for Developmental Dysplasia of the Hip.

BACKGROUND: Preoperative evaluation of femoral anteversion to predict postoperative stem anteversion aids the selection of an appropriate prosthesis and optimizes the combined anteversion in total hip arthroplasty (THA) for developmental dysplasia of the hip (DDH). The conventional prediction methods are based on the femoral anteversion measurement at the location of the femoral head and/or neck. However, varied differences between femoral anteversion and postoperative stem anteversion were demonstrated. This study investigated the predictive role of a new method based on the principle of sagittal three-point fixation. METHODS: From January 2017 to December 2018, a total of 133 DDH hips that underwent THA were retrospectively analyzed. There were 76 Crowe type I, 27 type II, and 30 type III hips. The single-wedge stem was used in 49 hips, and the double-wedge stem was used in 84 hips. Preoperative native femoral anteversion at the femoral head-neck junction, anterior cortex anteversion at 2 levels of the lesser trochanter, posterior cortex anteversion at 5 levels of the femoral neck, and postoperative stem anteversion were measured using two-dimensional computed tomography. Predictive anteversion by the new method was calculated as the average anteversion formed by the anterior cortex at the lesser trochanter and the posterior cortex at the femoral neck. RESULTS: For hips with different neck heights, different Crowe types, different stem types, or different femoral anteversions, native femoral anteversion showed widely varied differences and correlations with stem anteversion, with differences ranging from -1.27 ± 8.33° to -13.67 ± 9.47° and correlations ranging from 0.122 (p = 0.705, no correlation) to 0.813. Predictive anteversion formed by the anterior cortex at the lesser trochanter proximal base and posterior cortex 10 mm above the lesser trochanter proximal base showed no significant difference with stem anteversion, with less varied differences (0.92 ± 7.52°) and good to excellent correlations (r = 0.826). CONCLUSION: Adopting our new method, predictive anteversion, measured as the average anteversion of the anterior cortex at the lesser trochanter proximal base and posterior cortex 10 mm above the lesser trochanter proximal base, predicted postoperative stem anteversion more reliably than native femoral anteversion.

Shape-memory sawtooth-arm embracing clamp used in complex femoral revision hip arthroplasty for stem stability: average 9-year follow-up study.

BACKGROUND: Nickel-Titanium shape-memory sawtooth-arm embracing clamps (SSECs) have been used in revision total hip arthroplasties (rTHAs) to protect stem stability. This study was to introduce this technique and report its mid to long-term clinical and radiographic outcomes. METHODS: We retrospectively reviewed all patients implanted with SSECs in our department from January 2008 to December 2015. 41 patients (41 hips) were finally included. Radiographs and Harris hip scores (HHS) were collected. Radiographs were blindly analyzed for evidence of loosening, subsidence and stress shielding. HHS were compared to previous records by student's t tests. The average follow-up period was 9.3 years. RESULTS: All stems were stably fixed with no signs of loosening. The mean stem subsidence was 0.9 mm (range, 0 to 3 mm). Only one patient (2.4%) demonstrated the fourth degree of stress shielding, with the others none or minor bone resorption. The mean HHS at the final follow-up was 84.2 (range, 81 to 91), which was improved from 17.4 (range, 0 to 37) before surgery. No implant failures or re-revisions occurred. Dislocation occurred in 1 case during the follow-up period. CONCLUSIONS: The SSEC protected stem fixation and achieved favorable clinical and radiographic outcomes in this 9-year follow-up study. It offered an additional extramedullary fixation option for surgeons to choose from in treating complex femoral revision arthroplasties.

A multi-branch network to detect post-operative complications following hip arthroplasty on X-ray images.

Background: Postoperative complications following total hip arthroplasty (THA) often require revision surgery. X-rays are usually used to detect such complications, but manually identifying the location of the problem and making an accurate assessment can be subjective and time-consuming. Therefore, in this study, we propose a multi-branch network to automatically detect postoperative complications on X-ray images. Methods: We developed a multi-branch network using ResNet as the backbone and two additional branches with a global feature stream and a channel feature stream for extracting features of interest. Additionally, inspired by our domain knowledge, we designed a multi-coefficient class-specific residual attention block to learn the correlations between different complications to improve the performance of the system. Results: Our proposed method achieved state-of-the-art (SOTA) performance in detecting multiple complications, with mean average precision (mAP) and F1 scores of 0.346 and 0.429, respectively. The network also showed excellent performance at identifying aseptic loosening, with recall and precision rates of 0.929 and 0.897, respectively. Ablation experiments were conducted on detecting multiple complications and single complications, as well as internal and external datasets, demonstrating the effectiveness of our proposed modules. Conclusion: Our deep learning method provides an accurate end-to-end solution for detecting postoperative complications following THA.

Upregulated miR­378a­3p expression suppresses energy metabolism and promotes apoptosis by targeting a GLUT­1/ALDOA/PKM2 axis in esophageal carcinoma.

Esophageal squamous cell carcinoma (ESCC) is an aggressive malignancy of the digestive system with increasing incidence and mortality rates. The biological roles of microRNA (miR)-378a-3p in tumor cells remain contested, and the mechanisms underlying the functions, energy metabolism, and cell survival mechanisms in ESCC cells are yet to be fully elucidated. In the present study, miR-378a-3p overexpression and negative control plasmids were transfected into ECA-109 cells using electroporation. Western blotting was used to detect the relative expression of proteins, and flow cytometry was used to detect cell apoptosis. Subsequently, ELISA assays were performed to determine enzyme activity, and an ATP detection kit was used to measure ATP content. Dual-luciferase reporter assays were performed to identify the target genes of miR-378a-3p. The results of the present study demonstrated that miR-378a-3p inhibited the gene expression and enzyme activities of glucose transporter protein 1 (GLUT-1), Aldolase A (ALDOA), and pyruvate kinase M2 (PKM2), all of which are involved in the glycolytic pathway of cells. Energy metabolism was suppressed by miR-378a-3p by reducing ATP content, and this downregulated the expression of Bcl-2 and Survivin. Moreover, increased miR-378a-3p expression promoted cell apoptosis in the early stages by increasing the expression levels and the activity of Bad and Caspase-3, while inhibiting the expression levels of Bcl-2 and Survivin. The results of the present study also demonstrated that GLUT-1/ALDOA/PKM2 were target genes of miR-378a-3p. Notably, miR-378a-3p blocked energy production and promoted the apoptosis of tumor cells via the downregulation of glycolytic enzyme expression and by reducing the mitochondrial membrane potential in ESCC. Bad, Caspase-3, Survivin, and Bcl-2 may be associated with blocking energy production and promoting apoptosis via miR-378a-3p in ESCC cells.

Indicators and medical tests to identify lower limb swelling causes after total knee arthroplasty: a Delphi study with multidisciplinary experts.

BACKGROUND: Lower limb swelling after total knee arthroplasty (TKA) hinders surgical effectiveness. The poor results of studies on swelling interventions are due to the lack of a classification of swelling causes through appropriate medical tests. A gold standard is missing. This study aimed to clarify the causes of TKA postoperative swelling and how to identify them through indicators and medical tests by consulting a wide range of experts from multiple disciplines. METHOD: The Delphi method was used. A first draft of the index was prepared based on a systematic search of the literature. A total of 11 experts from several disciplines were invited to evaluate the rationality of the indicators and suggest modifications. After two rounds of consultation, the experts reached a consensus, and the consultation was stopped. RESULTS: The response rate of the 11 experts was 100%, and the authoritative Cr was 0.896. Kendall's W values for opinion coordination of the two rounds of consultation were 0.262 and 0.226, respectively (P < 0.001). Among the final indicators, there were 4 primary indicators for swelling cause classification (inflammatory response, poor venous return, joint hematoma, muscle damage, and healing), 19 secondary and 19 tertiary indicators. CONCLUSION: The indications obtained by systematic literature review and multidisciplinary expert consultation are reliable and scientific. Multiple causes of lower extremity swelling after TKA were identified. Blood test indicators can reflect an inflammatory response, suggest poor venous return, and reflect muscle damage and healing progress. Ultrasound scans are needed to identify underlying thrombotic or valvular problems, joint hematomas, and muscle damage. These tests help clinicians and researchers determine the cause of swelling after TKA and take appropriate management.

Allogeneic Adipose-Derived Mesenchymal Stem Cell Transplantation Alleviates Atherosclerotic Plaque by Inhibiting Ox-LDL Uptake, Inflammatory Reaction and Endothelial Damage in Rabbits.

Atherosclerosis (AS) is a chronic inflammatory disease of arteries fueled by lipids. It is a major cause of cardiovascular morbidity and mortality. Mesenchymal stem cells have been used for the treatment of atherosclerotic lesions. Adipose-derived stem cells (ADSCs) have been shown to regulate the activation state of macrophages and exhibit anti-inflammatory capabilities. However, the effect of allogeneic ADSCs in the treatment of AS have not been investigated. In this study, the early treatment effect and preliminary mechanism analysis of allogeneic rabbit ADSCs intravenous transplantation were investigated in a high-fat diet rabbit model. The polarization mechanism of rabbit ADSCs on the macrophage was further analyzed in vitro. Compared with the model group, blood lipid levels declined, the plaque area, oxidized low-density lipoprotein (ox-LDL) uptake, scavenger receptor A1 and cluster of differentiation (CD) 36 levels were all significantly reduced, and the accumulation of inflammatory M1 macrophages, apoptosis, interleukin (IL)-6 and tumor necrosis factor (TNF)-α expression were decreased. The endothelial cells (CD31), M2 macrophages, IL-10 and the transforming growth factor (TGF)-ß levels increased. In vitro, ADSCs can promote the M1 macrophage phenotypic switch toward the M2 macrophage through their secreted exosomes, and the main mechanism includes increasing arginase 1 expression and IL-10 secretion, declining inducible nitric oxide synthase (iNOS) expression and TNF-α secretion, and activating the STAT6 pathway. Therefore, allogeneic rabbit ADSC transplantation can transmigrate to the aortic atherosclerotic plaques and show a good effect in lowering blood lipids and alleviating atherosclerotic plaque in the early stage of AS by inhibiting ox-LDL uptake, inflammatory response, and endothelial damage.

Postoperative hip center position is associated with gait symmetry in range of axial rotation in dysplasia patients after THA.

Background: This study aimed to explore whether pre- or postoperative hip structures or surgical changes significantly influence hip range of motion (ROM) symmetry in patients with hip dysplasia during gait after total hip arthroplasty (THA) and provide possible surgical suggestions. Methods: Fourteen patients with unilateral hip dysplasia underwent computed tomography before and after surgery to create three-dimensional hip models. Pre- and postoperative acetabular and femoral orientations, hip rotation centers (HRC), and femoral lengths were measured. Bilateral hip ROM during level walking after THA was quantified using dual fluoroscopy. The ROM symmetry in flexion-extension, adduction-abduction, and axial rotation was calculated using the symmetry index (SI). The relationship between SI and the above anatomical parameters and demographic characteristics was tested using Pearson's correlation and linear regression. Results: The average SI values for flexion-extension, adduction-abduction, and axial rotation during gait were -0.29, -0.30, and -0.10, respectively. Significant correlations were detected mainly in the postoperative HRC position. A distally placed HRC was associated with increased SI values for adduction-abduction (R = -0.47, p = 0.045), while a medially placed HRC was associated with decreased SI values for axial rotation (R = 0.63, p = 0.007). A regression analysis indicated that horizontal HRC positions significantly determined axial rotational symmetry (R2 = 0.40, p = 0.015). Normal axial rotation SI values were achieved with HRC between 17 mm medially and 16 mm laterally. Conclusions: Postoperative HRC position was significantly correlated with gait symmetry in the frontal and transverse planes in patients with unilateral hip dysplasia after THA. Surgical reconstruction of the HRC to between 17 mm medially and 16 mm laterally may contribute to gait symmetry.

Exploring expectations of Chinese patients for total knee arthroplasty: once the medicine is taken, the symptoms vanish.

BACKGROUND: Preoperative expectations of total knee arthroplasty (TKA) outcomes are important determinants of patient satisfaction. However, expectations of patients in different countries are affected by cultural background. The general goal of this study was to describe Chinese TKA patients' expectations. METHODS: Patients scheduled for TKA were recruited in a quantitative study(n = 198). The Hospital for Special Surgery Total Knee Replacement Expectations Survey Questionnaire was used for survey TKA patients' expectations. Descriptive phenomenological design was used for the qualitative research. Semi-structured interviews were conducted with 15 TKA patients. Colaizzi's method was used for interview data analysis. RESULTS: The mean expectation score of Chinese TKA patients was 89.17 points. The 4 highest score items were walk short distance, remove the need for walker, relieve pain and make knee or leg straight. The 2 lowest score items were employed for monetary reimbursement and sexual activity. Five main themes and 12 sub-themes emerged from the interview data, including multiple factors raised expectations, expectations of physical comfort, expect various activities back to normal, hope for a long joint lifespan, and expect a better mood. CONCLUSIONS: Chinese TKA patients reported a relatively high level of expectations, and differences across cultures result in different expectation points than other national populations, requiring adjustment of items when using assessment tools across cultures. Strategies for expectation management should be further developed. LEVEL OF EVIDENCE: Level IV.

Aspirin prevents estrogen deficiency-induced bone loss by inhibiting osteoclastogenesis and promoting osteogenesis.

BACKGROUND: Aspirin is a commonly used antipyretic, analgesic, and anti-inflammatory drug. Numerous researches have demonstrated that aspirin exerts multiple biological effects on bone metabolism. However, its spatiotemporal roles remain controversial according to the specific therapeutic doses used for different clinical conditions, and the detailed mechanisms have not been fully elucidated. Hence, in the present study, we aimed to identify the dual effects of different aspirin dosages on osteoclastic activity and osteoblastic bone formation in vitro and in vivo. METHODS: The effects of varying doses of aspirin on osteoclast and osteoblast differentiation were evaluated in vitro. The underlying molecular mechanisms were detected using quantitative real-time polymerase chain reaction, western blotting, and immunofluorescence techniques. An ovariectomized rat osteoporosis model was used to assess the bone-protective effects of aspirin in vivo. RESULTS: Aspirin dose-dependently suppressed RANKL-induced osteoclasts differentiation and bone resorption in vitro and reduced the expression of osteoclastic marker genes, including TRAP, cathepsin K, and CTR. Further molecular analysis revealed that aspirin impaired the RANKL-induced NF-κB and MAPK signaling pathways and prevented the nuclear translocation of the NF-κB p65 subunit. Low-dose aspirin promoted osteogenic differentiation, whereas these effects were attenuated when high-dose aspirin was administered. Both low and high doses of aspirin prevented bone loss in an ovariectomized rat osteoporosis model in vivo. CONCLUSION: Aspirin inhibits RANKL-induced osteoclastogenesis and promotes osteogenesis in a dual regulatory manner, thus preventing bone loss in vivo. These data indicate that aspirin has potential applications in the prevention and treatment of osteopenia.

CCL3 in the bone marrow microenvironment causes bone loss and bone marrow adiposity in aged mice.

The central physiological role of the bone marrow renders bone marrow stromal cells (BMSCs) particularly sensitive to aging. With bone aging, BMSCs acquire a differentiation potential bias in favor of adipogenesis over osteogenesis, and the underlying molecular mechanisms remain unclear. Herein, we investigated the factors underlying age-related changes in the bone marrow and their roles in BMSCs' differentiation. Antibody array revealed that CC chemokine ligand 3 (CCL3) accumulation occurred in the serum of naturally aged mice along with bone aging phenotypes, including bone loss, bone marrow adiposity, and imbalanced BMSC differentiation. In vivo Ccl3 deletion could rescue these phenotypes in aged mice. CCL3 improved the adipogenic differentiation potential of BMSCs, with a positive feedback loop between CCL3 and C/EBPα. CCL3 activated C/EBPα expression via STAT3, while C/EBPα activated CCL3 expression through direct promoter binding, facilitated by DNA hypomethylation. Moreover, CCL3 inhibited BMSCs' osteogenic differentiation potential by blocking ß-catenin activity mediated by ERK-activated Dickkopf-related protein 1 upregulation. Blocking CCL3 in vivo via neutralizing antibodies ameliorated trabecular bone loss and bone marrow adiposity in aged mice. This study provides insights regarding age-related bone loss and bone marrow adiposity pathogenesis and lays a foundation for the identification of new targets for senile osteoporosis treatment.

Age does matter in adolescents and young adults vs. older adults with lung adenocarcinoma: A retrospective analysis comparing clinical characteristics and outcomes in response to systematic treatments.

Adenocarcinoma is the most common histological type of lung cancer in adolescents and young adults (AYAs; ˂50 years of age). However, few clinical trials that have investigated systematic treatments regard AYAs as a special cohort, and the differences in progression-free survival (PFS) and overall survival (OS) between AYAs and older adults is still unclear. The present study compared clinical characteristics, targetable genomic mutations, toxicity, efficacy and prognostic response to systematic treatments in AYAs (n=251) and older adults (n=1,098) who were diagnosed with lung adenocarcinoma between January 2013 and December 2017 at YueBei People's Hospital (Shaoguan, China). Compared with older adults, AYAs with lung adenocarcinoma were more frequently female and non-smokers, with a higher ratio of patients receiving chemotherapy and targeted therapy, and fewer untreated. More AYAs harbored targetable genomic mutations, including epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) mutations, while more older adults harbored KRAS proto-oncogene GTPase mutations. EGFR L858R was significantly more prevalent among older adults, while 19Del was common in AYAs. AYAs showed a higher objective response rate (ORR) and a lower grade 3-4 treatment-related adverse event (TRAE) percentage following systematic chemotherapy, but shared a similar ORR and grade 3-4 TRAE percentage with older adults following targeted therapies. AYAs experienced a shorter progression-free survival time following EGFR-tyrosine kinase inhibitor (TKI) treatment due to the higher number of metastatic organs at the time of the initial cancer diagnosis. However, there was a survival advantage of AYAs over older adults in terms of the response to systemic chemotherapy, and an age of ˂50 years was indicated as one of the positive predictors for OS time. Overall, AYAs with lung adenocarcinoma harbored distinctive clinical and genomic characteristics, and exhibited PFS and OS disadvantages following first-line EGFR-TKIs and advantages following systematic chemotherapy. However, the age-related difference in prognosis existed solely in patients who received systematic chemotherapy.

Use of a Gigli Saw as a Substitute Osteotomy Tool When Oscillating Saw Malfunctions Occur During Hip Arthroplasty.

OBJECTIVE: The oscillating saw has some inherent disadvantages, such as notch formation and blood splash. The objective is to introduce the Gigli saw as a substitute osteotomy tool when oscillating saw malfunctions occur during surgery. METHODS: During our retrospective study, 120 patients (120 hips) who underwent primary total hip arthroplasty (THA) because of femoral neck fracture, femoral head necrosis, developmental hip dysplasia (Crowe I), or primary osteoarthritis between October 2017 and April 2020 at our institute were included. Sixty patients (26 men and 34 women) with a mean age of 67.3 years (±15.1 years) underwent femoral neck osteotomy using a Gigli saw. The other 60 patients (32 men and 28 women) with a mean age of 64.4 years (±18.8 years) underwent femoral neck osteotomy using an oscillating saw. Intraoperative evaluations, including osteotomy time, osteotomy height, number of notch formations, and blood splash generation, were performed. Routine anteroposterior views of the pelvis and proximal femur were obtained for all patients after surgery. RESULTS: The mean osteotomy times were 26.60 ± 14.80 s and 31.80 ± 14.20 s with the oscillating saw and Gigli saw, respectively (t = 1.964, P = 0.0519). The mean osteotomy heights were 1.26 ± 0.22 cm and 1.20 ± 0.14 cm with the oscillating saw and Gigli saw, respectively (t = 1.782, P = 0.0773). The use of a Gigli saw did not result in bone notch formation or blood splash generation when multiple blood splashes were generated in the oscillating saw group. Postoperative radiographs showed no prostheses malposition in the Gigli saw and oscillating saw groups. CONCLUSION: The Gigli saw has various advantages and can be a substitute tool for femoral neck osteotomy during THA when oscillating saw malfunctions occur.

Application of a novel osteotomy instrumentation as a substitute tool in total hip arthroplasty.

BACKGROUND: Mechanical failure, power shortage, and inadvertent contamination of the oscillating saw occasionally occurs in actualizing femoral neck osteotomy during total hip arthroplasty (THA); however, no appropriate alternative solution is currently available. This study aimed to introduce a novel osteotomy instrumentation (fretsaw, jig, cable passer hook) as a substitute tool while the oscillating saw was unavailable during THA. METHODS: This study included 40 patients (40 hips) who underwent femoral neck osteotomy during primary THA using the new osteotomy instrumentation (n = 20) and the oscillating saw (n = 20). Clinical data and intraoperative findings of all patients were evaluated. RESULTS: The mean osteotomy time was 22.3 ± 3.1 s (range, 17-30 s) and 29.4 ± 3.7 s (range, 25-39 s) in the oscillating saw group and in the new osteotomy instrumentation group, respectively (P < 0.001). The Harris Hip Score (HHS) improved in both groups; the mean HSS was 82.3 ± 2.5 and 83.3 ± 3.5 in the oscillating saw group and new osteotomy instrumentation group at 6 months after surgery, respectively (P = 0.297). CONCLUSIONS: The original osteotomy instrumentation can be an ideal substitute tool for femoral neck osteotomy in THA, especially when the oscillating saw is unavailable or malfunctioning.

Fusion of multimodality image and point cloud for spatial surface registration for knee arthroplasty.

BACKGROUND: Image-guided computer-aided navigation system is an indispensable part of computer assisted orthopaedic surgery. However, the location and number of fiducial markers, the time required to localise fiducial markers in existing systems affect their effectiveness. METHOD: The study proposed that spatial surface registration between the point cloud on the surface of the fusion model based on preoperative knee MRI and CT images and the point cloud on the cartilage surface captured by intraoperative laser scanner could solve the above limitations. RESULTS: The experimental results show that the registration error of the method is less than 2 mm, but the total time from scanning the point cloud on patient's cartilage surface to registering it with the point cloud in preoperative image space is less than 2 min. CONCLUSION: The method achieves the registration accuracy similar to existing methods without selecting anatomical corresponding points, which is of great help to the clinic.

Reliability and validity test of a novel three-dimensional acetabular bone defect classification system aided with additive manufacturing.

BACKGROUND: Accurate assessment of acetabular defects and designing precise and feasible surgical plans are essential for positive outcomes of hip revision arthroplasty. Additive manufacturing (AM) is a novel technique to print physical object models. We propose a three-dimensional acetabular bone defect classification system aided with AM model, and further assess its reliability and validity under blinded conditions. METHODS: We reviewed 104 consecutive patients who underwent hip revision arthroplasty at our department between January 2014 and December 2019, of whom 45 had AM models and were included in the reliability and validity tests. Three orthopedic surgeons retrospectively evaluated the bone defects of these 45 patients with our proposed classification, made surgical plans, and repeated the process after 2 weeks. The reliability and validity of the classification results and corresponding surgical plans were assessed using the intra-class correlation coefficient or kappa correlation coefficient. RESULTS: The reliability and validity of the classification results were excellent. The mean initial intra-class correlation coefficient for inter-observer reliability was 0.947, which increased to 0.972 when tested a second time. The intra-observer reliability ranged from 0.958 to 0.980. Validity of the classification results also showed a high kappa correlation coefficient of 0.951-0.967. When considering corresponding surgical plans, the reliability and validity were also excellent, with intra-class correlation coefficients and kappa correlation coefficients measuring all over 0.9. CONCLUSIONS: This three-dimensional acetabular defect classification has excellent reliability and validity. Using this classification system and AM models, accurate assessment of bone defect and reliable surgical plans could be achieved. This classification aided with AM is a promising tool for surgeons for preoperative evaluation.

Computer simulation of optimal lipped polyethylene liner orientation against prosthetic impingement.

BACKGROUND: Lipped or elevated acetabular liners are to improve posterior stability and are widely used in hip arthroplasty. However, concerns of increasing impingement exist when using such liners and optimal orientation of the elevated rim remains unknown. We aimed to identify the impact of lipped liner on the range of motion (ROM) before impingement and propose its optimal orientation. METHODS: An isochoric three-dimensional model of a general hip-replacement prosthesis was generated, and flex-extension, add-abduction and axial rotation were simulated on a computer. The maximum ROM of the hip was measured before the neck impinged on the liner. Different combinations of acetabular anteversion angles ranging from 5 to 30 degrees, and lipped liner orientations from posterior to anterior were tested. RESULTS: When acetabular anteversion was 10 or 15 degrees, placing the lip of the liner in the posterosuperior of the acetabulum allowed satisfactory ROM in all directions. When acetabular anteversion was 20 degrees, extension and external rotation were restricted. Adjusting the lip to the superior restored satisfactory ROM. When acetabular anteversion was 25 degrees, only placing the lip into the anterosuperior could increase extension and external rotation to maintain satisfactory ROM. CONCLUSIONS: This study showed that optimal lipped liner orientation should depend on acetabular anteversion. When acetabular anteversion was smaller than 20 degrees, placing lip in the posterior allowed an optimally ROM. When acetabular anteversion was greater than 20 degrees, adjusting lip to the anterior allowed a comprehensive larger ROM to avoid early impingement.

Postoperative Hip Center Position Associated With the Range of Internal Rotation and Extension During Gait in Hip Dysplasia Patients After Total Hip Arthroplasty.

Background: Total hip arthroplasty (THA) for hip dysplasia patients is sometimes complex and compromises pathomorphological changes in these patients. However, it remains unclear whether it is preoperative deformities or postoperative structures or anatomic changes during THA that have the most remarkable correlation with the hip dynamic function during gait. The purpose of this study was to investigate this relationship and propose insights into the surgical reconstruction strategy in patients with developmental dysplasia of the hip. Methods: A total of 21 unilateral hip dysplasia patients received computed tomography scans for the creation of 3D hip models before surgery and at the last follow-up. Acetabular and femoral orientations, hip center positions, and femoral length were measured before and after THA. Hip kinematics of the operated side during gait was quantified using a dual fluoroscopic imaging technique. Pearson correlation and multiple linear regression were performed to evaluate the relationship between hip maximum range of motion in six directions and demographics characters and above hip anatomic parameters before and after THA and their changes in surgery. Results: Pearson correlation analysis found significant correlations with the gait range of motion mainly in postoperative structures, including postoperative hip center positions and acetabulum and combined anteversion. Further multiple linear regression indicated that a laterally placed hip center was significantly correlated with an increased internal rotation (R 2 = 0.25, p = 0.021), which together with increased postoperative acetabulum anteversion explained 45% of external rotation decreasing (p = 0.004). A proximally placed hip center was correlated with more extension (R 2 = 0.30, p = 0.010). No significant demographic characters or preoperative deformities or surgical changes were included into other multiple regression models. Conclusion: Strong correlations between postoperative structures, especially hip center positions and gait range of motion in unilateral hip dysplasia patients after THA were found. It indicated that postoperative prosthesis structures, particularly hip center positions had significant impact on the hip gait motion range and should be treated with particular caution in surgery.

Favorable osteogenic activity of iron doped in silicocarnotite bioceramic: In vitro and in vivo Studies.

BACKGROUND: Calcium phosphate silicate (Ca5(PO4)2SiO4 or CPS) is a promising bioceramic for bone grafting. Iron (Fe) is a trace element in the human body that has been reported to enhance the mechanical strength of CPS ceramics. However, the exact biofunctions of Fe, combined with another human trace element, viz. silicon (Si), in CPS and the optimal dose for Fe addition must be further investigated. METHODS: In vitro: the morphology, structure and cell adhesion were observed by SEM; the ability to promote osteogenic differentiation and mineralization was explored by ALP and alizarin red staining; the expression of osteogenic-specific genes and proteins was detected by PCR, WB and immunofluorescence. In vivo: Further exploration of bone regeneration capacity by establishing a skull defect model. RESULTS: In vitro, we observed increased content of adhesion-related proteins and osteogenic-related genes expression of Fe-CPS compared with CPS, as demonstrated by immunofluorescence and polymerase chain reaction experiments, respectively. In vivo micro-computed tomography images, histomorphology, and undecalcified bone slicing also showed improved osteogenic ability of Fe-CPS bioceramics. CONCLUSION: With the addition of Fe2O3, the new bone formation rate of the Fe-CPS scaffold after 12 weeks increased from 9.42% to 43.76%. Moreover, both in vitro and in vivo experimental outcomes indicated that Fe addition improved the CPS bioceramics in terms of their osteogenic ability by promoting the expression of osteogenic-related genes. Fe-CPS bioceramics can be employed as a novel material for bone tissue engineering on account of their outstanding new bone formation ability. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: This study suggests that Fe-CPS bioceramics can be employed as a novel material for bone tissue engineering on account of their outstanding new bone formation ability,which provides promising therapeutic implants and strategies for the treatment of large segmental bone defects.

Positive Correlation Between the Femur Neck Shaft and Anteversion Angles: A Retrospective Computed Tomography Analysis in Patients With Developmental Dysplasia of the Hip.

BACKGROUND: This study aimed to explore the anatomical correlation between the femoral neck shaft angle (NSA) and femoral anteversion angle (AA) in patients with developmental dysplasia of the hip based on the Crowe classification and provide a novel method to estimate the femoral AA on anteroposterior pelvic radiographs. METHODS: A total of 208 patients with dysplastic hips who underwent total hip arthroplasty at our institution were retrospectively included. Preoperative physiological AA and NSA were determined via 3-dimensional computed tomography. Linear regressions and Pearson's coefficients were calculated to assess the correlation between the femoral NSA and femoral AA. RESULTS: A total of 416 hips were divided into 5 subgroups: 99 normal, 143 type I, 71 type II, 63 type III, and 40 type IV hips following the Crowe classification. Dysplastic femurs had significantly higher AAs than normal hips (25.2° vs 31.4° vs 33.3° vs 35.5° vs 41.7°). Significant positive correlations between the AA and NSA were observed in normal (r = 0.635), type I (r = 0.700), type II (r = 0.612), and type III (r = 0.638) hips (P < .001); however, no meaningful correlation was observed in type IV hips (r = 0.218, P = .176). CONCLUSION: The NSA and AA correlated positively and significantly in the normal and dysplastic Crowe type I-III hips. The relationship between the NSA and AA indicates torsion of the proximal femur and offers an opportunity for straightforward estimation of AA based on NSA.