Evaluating the accuracy of a new robotically assisted system in cadaveric total knee arthroplasty procedures.

BACKGROUND: Robot-assisted total knee arthroplasty (TKA) has been shown to facilitate high-precision bone resection, which is an important goal in TKA. The aim of this cadaveric study was to analyze the accuracy of the target angle and bone resection thickness of a recently introduced robotic TKA system. METHODS: This study used 4 frozen cadaveric specimens (8 knees), 2 different implant designs, navigation, and a robotic system. The 4 surgeons who participated in this study were trained and familiar with the basic principles and operating procedures of this system. The angle of the bone cuts performed using the robotic system was compared with the target angles from the intraoperative plan. For each bone cut, the resection thickness was recorded and compared with the planned resection thickness. RESULTS: The mean angular difference for all specimens was less than 1°, and the standard deviation was less than 2°. The mean difference between the planned and measured angles was close to 0 and not significantly different from 0 except for the difference in the frontal tibial component angle, which was 0.88°. The mean difference in the hip-knee-ankle axis angle was - 0.21°± 1.06°. The mean bone resection difference for all specimens was less than 1 mm, and the standard deviation was less than 0.5 mm. CONCLUSIONS: The results of the cadaveric experimental study showed that the new TKA system can realize highly accurate bone cuts and achieve planned angles and resection thicknesses. Despite the limitations of small sample sizes and large differences between cadaveric and clinical patients, the accuracy of cadaveric experiments provides strong support for subsequent clinical trials.

scRNA-seq revealed high stemness epithelial malignant cell clusters and prognostic models of lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is one of the sole causes of death in lung cancer patients. This study combined with single-cell RNA-seq analysis to identify tumor stem-related prognostic models to predict the prognosis of lung adenocarcinoma, chemotherapy agents, and immunotherapy efficacy. mRNA expression-based stemness index (mRNAsi) was determined by One Class Linear Regression (OCLR). Differentially expressed genes (DEGs) were detected by limma package. Single-cell RNA-seq analysis in GSE123902 dataset was performed using Seurat package. Weighted Co-Expression Network Analysis (WGCNA) was built by rms package. Cell differentiation ability was determined by CytoTRACE. Cell communication analysis was performed by CellCall and CellChat package. Prognosis model was constructed by 10 machine learning and 101 combinations. Drug predictive analysis was conducted by pRRophetic package. Immune microenvironment landscape was determined by ESTIMATE, MCP-Counter, ssGSEA analysis. Tumor samples have higher mRNAsi, and the high mRNAsi group presents a worse prognosis. Turquoise module was highly correlated with mRNAsi in TCGA-LUAD dataset. scRNA analysis showed that 22 epithelial cell clusters were obtained, and higher CSCs malignant epithelial cells have more complex cellular communication with other cells and presented dedifferentiation phenomenon. Cellular senescence and Hippo signaling pathway are the major difference pathways between high- and low CSCs malignant epithelial cells. The pseudo-temporal analysis shows that cluster1, 2, high CSC epithelial cells, are concentrated at the end of the differentiation trajectory. Finally, 13 genes were obtained by intersecting genes in turquoise module, Top200 genes in hdWGCNA, DEGs in high- and low- mRNAsi group as well as DEGs in tumor samples vs. normal group. Among 101 prognostic models, average c-index (0.71) was highest in CoxBoost + RSF model. The high-risk group samples had immunosuppressive status, higher tumor malignancy and low benefit from immunotherapy. This work found that malignant tumors and malignant epithelial cells have high CSC characteristics, and identified a model that could predict the prognosis, immune microenvironment, and immunotherapy of LUAD, based on CSC-related genes. These results provided reference value for the clinical diagnosis and treatment of LUAD.

Construction of a multiple-class classifier based on mRNAs and lncRNA FAM66A and PSORS1C3 for predicting distant metastasis in lung adenocarcinoma.

Background: There are several mechanisms believed to be essential for the development of distant metastasis in lung adenocarcinoma (LUAD), but the prediction of distant metastasis is still a challenge. The purpose of the present study was to examine the specific changes in RNA expression, including long non-coding RNAs (lncRNAs) in distant metastasis patients. Methods: We compared differentially expressed genes involved in distant metastasis from otherwise non-metastasis and healthy adults using a gene expression profile. We first ranked gene sets (or gene signatures) that identify each class. An advanced multiple-class classifier was built based on the gene sets. Our classifier consisted of 282 genes and could predict cancer and distant metastasis with error rates of approximately 0.01 and 0.2, respectively. Then, gene networks were built to undermine gene relations to each class. Results: Cytochrome P450 family 4 subfamily F member 12 (CYP4F12) was the first gene in the ranking of the distant metastasis case. Down syndrome cell adhesion molecule (DSCAM) was the top gene in the rank list of the non-metastasis case. Solute carrier family 6 member 4 (SLC6A4) was associated with normal tissues. LncRNA family with sequence similarity 66 member A (FAM66A) and lncRNA PSORS1C3 were found to be associated with tumor metastasis. Conclusions: Our classifier could successfully predict distant metastasis in LUAD patients. LncRNA FAM66A and lncRNA PSORS1C3 in our model could play a role in cancer development.

[Clinical effect of Corail femoral prosthesis with different offset in total hip arthroplasty].

OBJECTIVE: To explore the early clinical efficacy of primary total hip arthroplasty(THA) with Corail standard stems (KS type) and high offset stems (KHO type), by analyzing the postoperative radiographic parameters of different offset of femoral components with Corail stem which has a neck-shaft angle of 135 ° in unilateral primary THA, by comparing the measurement results on both sides and analyzing the reconstruction of the postoperative femoral offset and the hip joint function recovery. METHODS: A retrospective analysis was made of 186 patients with unilateral hip joint lesions who underwent the first total hip arthroplasty with Johnson & Johnson Corail prostheses from January 2015 to June 2017. According to the use of femoral prostheses with different eccentricities during the operation, the patients were divided into high eccentricity group and standard eccentricity group. In the high eccentricity group, there were 52 cases of Corail high eccentricity prosthesis(KHO type), including 20 females and 32 males;aged 21 to 71 years old with an average of(50.6±13.2) years;body mass index(BMI) was (26.0±4.1) kg/m2. The standard eccentricity group included 134 Corail standard femoral stem prostheses(KS type), 57 females and 77 males;aged 18 to 77 years old with an average of (47.3±14.0) years;BMI was (25.3±3.5) kg/m2. The abduction arm, femoral eccentricity, acetabular eccentricity and the length difference of lower limbs were measured on the postoperatively positive X-ray film of the hip joint. Harris score and related complications were recorded before and after the operation, and the stability of the prosthesis was analyzed. RESULTS: There were significant differences in femoral eccentricity, joint eccentricity and abduction arm between the affected side and the healthy side in the high eccentricity group(P<0.05). There were significant differences in femoral eccentricity and acetabular eccentricity between the affected side and the healthy side in the standard eccentricity group(P<0.05). There were significant differences in combined eccentricity, abduction arm and length of lower limbs between two groups(P<0.05). In the high eccentricity group, the abduction arm of the affected hip joint was positively correlated with the femoral eccentricity, acetabular eccentricity and joint eccentricity(r=0.633, P<0.001;r=0.384, P=0.005;r=0.690, P<0.001). The same results were also obtained in the healthy side(r=0.688, P<0.001;r=0.574, P<0.001;r=0.765, P<0.001). In the standard eccentricity group, the abduction arm of the affected hip joint was positively correlated with the femoral eccentricity, acetabular eccentricity and combined eccentricity(r=0.734, P<0.001;r=0.418, P<0.001;r=0.749, P<0.001). The same results were also obtained in the healthy side(r=0.775, P<0.001;r=0.397, P<0.001;r=0.773, P<0.001). The difference of the length of both lower limbs was significantly correlated with the difference of bilateral joint eccentricity and bilateral abduction arm (r=0.376, P=0.006;r=-0.346, P=0.012). There was no significant correlation between the difference of the length of both lower limbs and the difference of bilateral joint eccentricity and bilateral abduction arm (r=-0.009, P=0.919;r=-0.036, P=0.682). There was no significant difference in Harris score between two groups at the last follow-up(P>0.05). At the last follow-up, Trendelenburg was negative in all patients in both groups, and the prostheses were stable. CONCLUSION: Both Corail standard stem and high offset stem may be effectively reconstruct the femoral offset, reconstruct the anatomical structure and biomechanics of the hip joint, and maintain the length of lower limbs and the stability of the hip joint in the unilateral primary total hip arthroplasty. Although the offset of the femur was not reconstructed normally in some cases, the stability of the components and postoperative function were not affected.

The application of custom-made 3D-printed titanium augments designed through surgical simulation for severe bone defects in complex revision total hip arthroplasty.

BACKGROUND: With the development of radiology and three-dimensional (3D) printing technology, custom-made 3D-printed titanium augments have been more widely used. However, the radiological and clinical outcomes of custom-made augments lack reports. To better understand the clinical effect of using 3D-printed titanium augments and the significance of accurate placement, the aim of this study was to assess the outcomes when using custom-made 3D-printed titanium augments and to validate the idea that surgical simulation should be done before designing custom-made augments. METHODS: A retrospective review was conducted on 31 surgical simulations and revision total hip arthroplasties using custom-made 3D-printed titanium augments. The safe zone, cup position, and hip rotation center were measured on anteroposterior radiographs. Clinical outcomes were assessed with a mean 21.1 months of follow-up. RESULTS: All patients were positioned within the safe zone, and none of the acetabular cups nor the custom-made augments had any evidence of migration at the latest follow-up. A strong correlation was found between the planned cup position and the postoperative position. The average vertical position of the center of rotation was significantly increased from 3.55 cm to 2.35 cm. The mean Harris Hip Score was increased from 40.81 preoperatively to 65.46 postoperatively. Complications included gait abnormality, groin pain, fracture of the greater trochanter, and partial palsy of the sciatic nerve. However, patient satisfaction reached 92.3%. CONCLUSION: Surgical simulations help to design custom-made augments accurately and improve surgical plans. Acetabular components supported with custom-made 3D-printed augments is a useful method to bridge severe bone deficiencies. In this study, both the radiologic results and clinical outcomes were favorable. LEVEL OF EVIDENCE: Level 4.

[Application of high offset Corail femoral stem prosthesis in unilateral primary total hip arthroplasty].

OBJECTIVE: To investigate the application of high offset femoral stem prosthesis in primary total hip arthroplasty. METHODS: From January 2015 to June 2017, 51 patients with unilateral hip diseases who underwent primary total hip arthroplasty with Corail high offset femoral stem prosthesis(KHO type) were selected for retrospective study, including 20 females and 31 males;the age ranged from 21 to 71 years old with an average of(50.8±13.3) years old. The abduction arm, femoral offset, acetabular offset and the length of lower limbs were measured on the positive X-ray film of hip joint after operation. Harris scores before and after operation and related complications were recorded, and the stability of prosthesis was analyzed. RESULTS: The femoral offset, combined offset and abduction arm of the affected side were significantly greater than those of the healthy side(P<0.05). There was no significant difference in acetabular offset between the affected side and the healthy side (P>0.05). The femoral offset of 17 hips (33.3%) was reconstructed normally, of which 15 cases (88.2%) had equal length of both lower limbs. The femoral offset of 34 hips (66.7%) was greater than that of the healthy side, and 34 cases (100%) had equal length of both lower limbs. All 51 patients were followed up for(42.3±7.3) months. The Harris score increased from 38.0±7.6 before operation to 92.1±3.1 at the final follow-up(P<0.001). CONCLUSION: Although the high offset Corail prosthesis can not normally reconstruct the femoral offset in unilateral primary total hip arthroplasty, it does not affect the reconstruction of the length of lower limbs and the stability of the prosthesis.

A comparsion study between debridement, antibiotics, and implant retention and two-stage revision total knee arthroplasty for the management of periprosthetic joint infection occurring within 12 weeks from index total knee arthroplasty.

BACKGROUND: Managing periprosthetic joint infections are variable in practices. Debridement, antibiotics, and implant retention (DAIR) is one of the favorable interventions. Given that the success rate of the two-stage revision total knee arthroplasty (rTKA) might be overestimated. The purpose of this study is to compare the success rate between DAIR and standard two-stage rTKA with a comparable intervention time. METHODS: We retrospectively reviewed the consecutive knee periprosthetic joint infection cases which underwent DAIR or two-stage rTKA (all procedures were performed by the senior author) within 12 weeks since their primary TKA between July 2009 and October 2019. Average follow-up was 72.20 ± 40.70 months (range 29-148 months) in the DAIR group compared to 89.14 ± 43.06 months after spacer insertion (range 29-163 months) in the two-stage revision group (P = 0.156). According to different interventions, demographic data; timing of surgical intervention; hospital for special surgery knee score; and success rate were collected and compared between the DAIR group and two-stage revision group. Failure of treatment was based on the Delphi consensus and the fate of spacers. The pathogen types and failure cases were also recorded and analyzed. RESULTS: Average follow-up was 72.20 ± 40.70 months (range 29-148 months) in the DAIR group compared to 89.14 ± 43.06 months after spacer insertion (range 29-163 months) in the two-stage revision group. Time from index surgery was 3.90 ± 2.92 weeks (range 0-12 weeks) in the DAIR group, and 5.11 ± 2.86 weeks (range 0-12 weeks) in the 2-stage exchange group, respectively. The success rate was 70.0% and 75.0% in the DAIR group and two-stage revision group, respectively. But no significant differences were observed between the two groups. CONCLUSION: DAIR demonstrated comparable effectiveness with two-stage rTKA. We recommended DAIR as a choice for patients with current infection within 12 weeks after primary TKA. For methicillin-resistant staphylococcal infections and fungal infections, two-stage rTKA might be preferred.

Effect of positive airway pressure on cardiac troponins in patients with sleep-disordered breathing: A meta-analysis.

BACKGROUND: Cardiac troponins are highly sensitive and specific biomarkers for cardiac injury. Previous studies evaluating the effect of positive airway pressure (PAP) on cardiac troponins in patients with sleep-disordered breathing (SDB) have yielded conflicting results. The meta-analysis was performed to examine the effect of PAP on cardiac troponins in SDB patients. METHODS: PubMed, Web of Science, and EMBASE before September 2021 on original English language studies were searched. The data on cardiac troponins in both baseline and post-PAP treatment were extracted from all studies. The data on the change of cardiac troponins in both PAP and control group were extracted from randomized controlled trials. Standardized mean difference (SMD) was used to synthesize quantitative results. RESULTS: A total of 11 studies were included. PAP treatment was not associated with a significant change in cardiac troponin T between the baseline and post-PAP treatment (SMD = -0.163, 95% confidence interval [CI] = -0.652 to 0.326, z = 0.65, p = .514). The pooled estimate of SMD of cardiac troponin I between the pre- and post-PAP treatment was 0.287, and the 95% CI was -0.586 to 1.160 (z = 0.64, p = .519). The pooled SMD of change of cardiac troponin T between the PAP group and control group was -0.473 (95% CI = -1.198 to 0.252, z = 1.28, p = .201). CONCLUSIONS: This meta-analysis revealed that PAP treatment was not associated with any change of cardiac troponin in SDB patients.

[Value of personalized extramedullary positioning technique on tibia side for coronal alignment of tibial prosthesis in total knee arthroplasty].

OBJECTIVE: To explore the coronal alignment of tibial prosthesis after osteotomy using personalized extramedullary positioning technique on tibia side in total knee arthroplasty (TKA). METHODS: A clinical data of 170 patients (210 knees) who underwent primary TKA between January 2020 and June 2021 and met the selection criteria was retrospectively analyzed. Personalized and traditional extramedullary positioning techniques were used in 93 cases (114 knees, personalized positioning group) and 77 cases (96 knees, traditional positioning group), respectively. The personalized extramedullary positioning was based on the anatomical characteristics of the tibia, a personalized positioning point was selected as the proximal extramedullary positioning point on the articular surface of the tibial plateau. There was no significant difference between the two groups in gender, age, body mass index, surgical side, course of osteoarthritis, and Kellgren-Lawrence classification ( P>0.05). The preoperative tibial bowing angle (TBA) formed by the proximal and distal tibial coronal anatomical axes in the personalized positioning group was measured and the tibia axis was classified, and the distribution of personalized positioning point was analyzed. The pre- and post-operative hip-knee-ankle angle (HKA), the lateral distal tibial angle (LDTA), and the postoperative tibia component angle (TCA), the excellent rate of tibial prosthesis alignment in coronal position were compared between the two groups. RESULTS: In the personalized positioning group, 58 knees (50.88%) were straight tibia, 35 knees (30.70%) were medial bowing tibia, and 21 knees (18.42%) were lateral bowing tibia. The most positioning points located on the highest point of the lateral intercondylar spine (62.07%) in the straight tibia group, while in the medial bowing tibia and lateral bowing tibia groups, most positioning points located in the area between the medial and lateral intercondylar spines (51.43%) and the lateral slope of the lateral intercondylar spine (57.14%), respectively. The difference in HKA between pre- and post-operation in the two groups was significant ( P<0.05); while the difference in LDTA was not significant ( P>0.05). There was no significant difference in preoperative LDTA and HKA and the difference between pre- and post-operation between groups ( P>0.05). But there was significant difference in postoperative TCA between groups ( P<0.05). The postoperative tibial plateau prosthesis in the traditional positioning group was more prone to varus than the personalized positioning group. The excellent rates of tibial prosthesis alignment in coronal position were 96.5% (110/114) and 87.5% (84/96) in personalized positioning group and traditional positioning group, respectively, showing a significant difference between groups ( χ 2=7.652, P=0.006). CONCLUSION: It is feasible to use personalized extramedullary positioning technique for coronal osteotomy on the tibia side in TKA. Compared with the traditional extramedullary positioning technique, the personalized extramedullary positioning technique has a higher excellent rate of tibial prosthesis alignment in coronal position.

Factors Affecting Squatting Ability in Total Knee Arthroplasty Using High Flexion Prosthesis.

PURPOSE: Total knee arthroplasty (TKA) is widely used as a treatment for knee osteoarthritis. Few studies have analysed the factors affecting the squatting ability of patients after TKA. The purpose of this study was to comprehensively analyse the factors affecting squatting ability after TKA and to determine which ones are important. PATIENTS AND METHODS: Three hundred primary TKA cases with a minimum 3-year follow-up were retrospectively analysed. All patients received a conventional posterior-stabilized TKA implant and underwent a standard perioperative care pathway. The patients were divided into two groups according to the squatting position and knee flexion angle while weight-bearing (Group I - inability to squat group, Group II - ability to squat group). Demographic, operative, and clinical data were collected. Radiographic assessment included joint line elevation, patellar position, posterior condylar offset (PCO), etc. Statistical analysis of the effect of all the above factors on squatting ability was performed. RESULTS: The preoperative range of motion and joint line of Group I were 82.9±12.6 and 3.24±1.07, respectively, and those of Group II were 107±9.6 and 1.83±0.89 respectively. The univariate analysis showed that age, prosthesis size, preoperative ROM and joint line position were correlated with squatting ability. But in the final multivariate analysis, joint line position and preoperative ROM were independent influencing factors that affected squatting ability after TKA (p value < 0.01). CONCLUSION: Preoperative ROM and joint line position were independent influencing factors affecting squatting ability after TKA. Patients should be counseled accordingly and be made to understand these factors. To ensure that patients can squat postoperatively, we should improve surgical techniques to control joint line elevation.

One-Stage Total Hip Arthroplasty with Modular S-ROM Stem for Patients with Bilateral Crowe Type IV Developmental Dysplasia.

OBJECTIVE: The aim of the present paper was to evaluate the results of one-stage total hip arthroplasty (THA) for patients with bilateral Crowe type IV developmental dysplasia of the hip (DDH). METHODS: Data for 58 patients (116 hips) with bilateral Crowe type IV DDH who had one-stage THA performed by the same surgeon during the period of April 2008 to February 2019 were retrospectively reviewed. The mean age of the patients was 37.3 years; 5 were men and 53 were women. All patients underwent THA through the posterolateral approach using the Pinnacle acetabular cup, a ceramic-on-ceramic bearing, and the modular S-ROM stem. Subtrochanteric shortening osteotomy was performed on 86/116 hips. Intraoperative conditions were recorded. Radiographic and functional outcomes were evaluated, and complications were recorded. RESULTS: All patients were followed up for an average of 71.3 ± 37.6 months (range, 12-140). The mean operative time was 276.5 ± 57.9 min (range, 175-540). The mean intraoperative blood loss was 933.6 ± 400.8 mL (range, 300-2000). The mean transfusion requirement was 1778 ± 798.0 mL (range, 575-4550). The mean length of hospital stay was 8.6 ± 3.7 days (range, 5-22). At the final follow-up, no loosening of acetabular and femoral components was observed. No osteolysis and heterotopic ossification occurred. The mean Harris hip scores were improved from 55.4 ± 14.3 preoperatively to 91.3 ± 4.2 postoperatively (P < 0.001) In terms of complications, no perioperative deaths were recorded. Deep vein thrombosis occurred in 1 hip, with no pulmonary embolism. Intraoperative femur fracture occurred in 3 hips, nerve injury in 1 hip, and leg length discrepancy in 1 patient. Postoperative dislocation occurred in 5 hips and nonunion in 1 hip. CONCLUSION: Our data demonstrated that one-stage bilateral THA for bilateral Crowe type IV DDH is feasible and can effectively restore hip function.

Model to Predict Need for Subtrochanteric Shortening Osteotomy During Total Hip Arthroplasty for Crowe Type IV Developmental Dysplasia.

BACKGROUND Indications for subtrochanteric shortening osteotomy (SSOT) during Crowe type IV developmental dysplasia of the hip (DDH) are unclear. The aim of this retrospective study was to create a model to predict the need for performing SSOT. MATERIAL AND METHODS One hundred forty-nine patients (186 hips) with Crowe Type IV DDH who underwent total hip arthroplasty (THA) with S-ROM implants from January 2010 to November 2018 were included in the study. The acetabular components were placed at the true acetabulum and the trial femoral component was inserted. Reduction then was attempted and if it could not be achieved, SSOT was performed. Using multivariable Cox regression analysis, a model was constructed that included age, sex, surgical history, use of a cone- or triangle-shaped sleeve, secondary acetabulum formation, and percentage of dislocation as predictive factors for SSOT. RESULTS SSOTs were performed on 140 of 186 hips. Secondary acetabulum formation was present in 27 hips (58.70%) in which SSOT was not performed 7 (5.00%) in which it was performed. Cone-shaped sleeves were used in 17 hips (36.96%) in which SSOT was not performed versus 15 (10.71%) hips in which it was performed. Dislocation occurred in 31.30±5.80% hips in which SSOT was performed versus 24.05±4.39% of those in which it was not performed. Percentage of dislocation was associated with an increased likelihood of SSOT (odds ratio [OR] 1.24, 95% confidence interval 1.11-1.38), whereas secondary acetabulum formation (OR 0.10, 0.03-0.33) and use of a cone-shaped sleeve (0.18, 0.06-0.53) were associated with decreased likelihood of SSOT. We established a model for prediction of SSOT with a nanogram and the discriminative ability (C statistic) of it was 0.918 (0.79-0.92). CONCLUSIONS Factors that significantly affect likelihood of performing an SSOT were identified and a model with significant ability to predict the need for SSOT in patients with Crowe Type IV DDH was created.

[Revision reasons and prosthesis selection of Crowe â £ developmental dysplasia of hip after total hip arthroplasty].

OBJECTIVE: To investigate revision reasons and prosthesis selection of Crowe Ⅳ developmental dysplasia of the hip (DDH) after total hip arthroplasty (THA). METHODS: A clinical data of 14 patients (15 hips) with Crowe Ⅳ DDH, who underwent a revision hip arthroplasty between January 2008 and May 2018, was retrospectively reviewed. There were 1 male (1 hip) and 13 females (14 hips). The age ranged from 27 to 63 years (mean, 45.0 years). There were 7 cases of left hip, 6 cases of right hip, and 1 case of bilateral hips. The prosthetic interfaces of primary THA were metal-on-polyethylene (MOP) in 9 hips, ceramic-on-ceramic (COC) in 4 hips, ceramic-on-polyethylene (COP) in 1 hip, and ceramic-on-metal in 1 hip. The time from primary THA to revision was 3-204 months (mean, 65.0 months). The causes of revision included aseptic loosening in 7 hips, dislocation in 3 hips, periprosthetic joint infection in 2 hips, osteolysis in 1 hip, nonunion of osteotomy in 1 hip, and a small-angle of femoral anteversion in 1 hip. Preoperative Harris score was 54.1±17.8 and the range of motion (ROM) of flexion was (92.7±20.2)°. Preoperative X-ray films showed the acetabular bone defect in 11 hips and osteolysis of femoral side in 4 hips. During the revision, the prostheses with COP and COC interfaces were used in 5 hips and 10 hips, respectively. Both acetabular and femoral revisions were performed in 11 hips and only femoral revision was performed in 4 hips. RESULTS: The mean operation time was 3.7 hours (range, 1.5-6.0 hours). The mean intraoperative blood loss was 940.0 mL (range, 200-2 000 mL). All patients were followed up 16-142 months (mean, 73.9 months). Postoperative X-ray films showed no difference in inclination and anteversion between primary THA and revision ( P>0.05). The height of rotation center and offset after revision were higher than those after primary THA, and the difference in offset was significant ( P<0.05). At last follow-up, the Harris score and ROM of flexion were 85.0±7.3 and (115.0±17.0)°, respectively, which were significantly higher when compared with those before revision ( t=8.909, P=0.000; t=4.911, P=0.000). Three hips underwent a re-revision operation. All protheses were fixed well and no radiolucent line, loosening, or subsidence was observed at last follow-up. CONCLUSION: The most common reason for revision in patients with Crowe Ⅳ DDH after THA was aseptic loosening. Due to high activity demand of this population, the prosthesis with MOP interface should be prevented and the prosthesis with COC interface could be alternative. Metal block, cup-cage, and reinforcement ring were reasonable solutions for reconstruction of acetabulum with severe bone defects and have satisfactory effectiveness. S-ROM prosthesis should be the preferred stem for neither primary THA or revision.

Comparison between the Staphylococci aureus and coagulase-negative staphylococci infected total joint arthroplasty treated by two-stage revision: A retrospective study with two year minimum follow-up.

BACKGROUND: Staphylococcus species are major pathogens of peri-prosthetic joint infection (PJI). Coagulase-positive staphylococci and coagulase-negative staphylococci have different intrinsic virulences. However, few studies have specifically compared the clinical manifestations and two-stage revision outcomes of PJI caused by these two species. METHODS: We retrospectively collected 260 arthroplasty patients who underwent a two-stage revision because of PJI from January 2003 to June 2015 in our institute because of PJI. Sixty-four patients (36 hips and 28 knees) and 23 patients (13 hips and 10 knees) were infected by coagulase-negative staphylococci (CoNS) and SA, respectively. RESULTS: The preoperative mean ESR value of the SA group was higher than that of the CoNS group (median, 60.9 VS 35.9; P < 0.001). Seventeen (73.9%) of the 23 SA infected patients had a sinus tract, while only 12 (18.8%) of the 64 CoNS-infected patients had this symptom (73.9% VS 18.8%; P < 0.001). At the time of follow-up, 58 (90.6%) of the 64 CoNS-infected patients had successfully controlled the infection. In the SA group, 20 (87.0%) patients ultimately acquired successful control (90.6% VS 87.0%; P = 0.923). Surgical history was identified as a potential risk factor (OR = 6.2, 95%CI 1.17-32.4) for prognosis when potential covariates were adjusted. CONCLUSIONS: SA infection has a higher ESR value and a more frequent occurrence of sinus tract. The infection control rate of the two-stage revision protocol was close to 90% for both SA and CoNS species, and there is no statistically significant difference in the eradication rate of infection between the SA and CoNS groups. Surgical history may be a good predictor of failure for PJI patients treated with two-stage revision.

Success Rate of Fungal Peri-Prosthetic Joint Infection Treated by 2-Stage Revision and Potential Risk Factors of Treatment Failure: A Retrospective Study.

BACKGROUND The aim of this study was to investigate the success rate of fungal peri-prosthetic joint infection treated by 2-stage revision and related factors of treatment failure to offer a better treatment protocol. MATERIAL AND METHODS We reviewed 18 joints (13 knees and 5 hips) of 17 patients (10 women and 7 men) diagnosed with fungal peri-prosthetic joint infection from January 2000 to June 2015 at our institute. The mean follow-up was 65.1 months (range, 25-129 months). All joints were treated with complete debridement, implantation of antifungal-loaded cement spacers, at least 6 weeks of parenteral antifungal agents, and delayed reimplantation. RESULTS Notably, 15 joints were infected with Candida, and molds were isolated in 3 joints. The median duration of resection arthroplasty and reimplantation was 33.9 weeks (range, 12-132 weeks). Thirteen (10 knees and 3 hips, 72.2%) of the 18 joints (13 knees and 5 hips) had no recurrent or persistent infection, while the remaining 5 joints (3 knees and 2 hips, 27.8%) failed to control infection after reimplantation of prosthesis or spacer. The long interval between prosthesis resection and reimplantation (69 weeks vs. 23.1 weeks, p=0.240) and mixed bacterial infection (80% vs. 46.2%, p=0.314) were associated with higher failure rate. CONCLUSIONS Debridement with the retention of the prosthesis is not an ideal treatment protocol for fungal peri-prosthetic joint infection; thus, a two-stage revision could be valid. We suggest that 6 weeks of parenteral antifungal agents are necessary, and 6 subsequent weeks of oral antifungal treatment is also important. We do not recommend that the two-stage revision be performed on patients who have more than 2 host risk factors.

[A study of total hip arthroplasty with subtrochanteric osteotomy in Crowe type â £ developmental dysplasia of hip].

Objective: To evaluate the effectiveness of total hip arthroplasty (THA) combined with subtrochanteric osteotomy in the treatment of Crowe type Ⅳdevelopmental dysplasia of the hip (DDH). Methods: Between April 2008 and June 2016, 71 patients with unilateral Crowe type Ⅳ DDH were treated with THA. Of 71 cases, 44 were performed with subtrochanteric osteotomy (osteotomy group) and 27 were performed without subtrochanteric osteotomy (non-osteotomy group). There was no significant difference in gender, age, body mass, height, body mass index, affected side, and preoperative Harris score between 2 groups ( P>0.05). The complications were recorded and the effectiveness was assessed by Harris score. Besides, the femoral dislocation height and the settling depth of sleeve were measured in the pelvic anteroposterior X-ray film pre- and post-operatively. Results: Osteotomy group was followed up 12-90 months (mean. 34.77 months), and non-osteotomy group was followed up 12-79 months (mean, 34.33 months). There was no significant difference in follow-up time between 2 groups ( t=-0.088, P=0.930). There was 11 cases of intraoperative or postoperative complications in osteotomy group, and 3 cases of postoperative complications in non-osteotomy group. Among the osteotomy group, 1 case had nonunion due to infection and received revision after 20 months. No loosening or dislocation of the implant occurred in both 2 groups. Significant differences were found in femoral dislocation height and settling depth of sleeve between 2 groups ( t=-8.452, P=0.000; t=6.783, P=0.000). Moreover，the osteotomy length was not correlated with the settling depth of sleeve ( r=-0.038, P=0.806). At last follow-up, there was no significant difference in Harris score between 2 groups ( t=-1.160, P=0.254). Conclusion: THA combined with subtrochanteric osteotomy can provide a favorable outcome for treating Crowe type Ⅳ DDH. Furthermore, patients with higher femoral dislocation and severely narrow femoral proximal canals are prone to be peformed with subtrochanteric osteotomy.

[Effect of ceramic on ceramic total hip arthroplasty in Crowe IV developmental dysplasia of the hip].

OBJECTIVE: To observe the clinical effect of ceramic on ceramic total hip arthroplasty(THA)in Crowe IV developmental dysplasia of the hip(DDH). METHODS: From April 2008 to December 2015, 137 hips of 111 Crowe IV DDH patients received THA using Forte or Delta ceramic on ceramic by one senior surgeon, which consists of 85 unilateral hips and 26 bilateral hips. The average age of the patients was(38.88±10.83) years old ranging from 18 to 68 years old. The mean follow-up was(41.16±21.50) months ranging from 12 to 96 months. All the patients were evaluated by Harris Hip Score. Radiographic evaluations were made preoperatively and during follow-up. Harris scores, the incidence of complications such as ceramic fracture, squeaking, dislocation were observed. RESULTS: The mean preoperative Harris score was 56.54±15.67, the mean postoperative Harris score was 88.30±6.86(P=0.017). Periprosthetic osteolysis was not deteced around any cup. No ceramic fracture occurred. There were 3 cases of revision surgery due to infection, losening of the stem and limb length discrepancy, respectively; 3 cases of dislocation occurred. Seventy-seven patients were recorded the gait and the hip mobility, the hip flexion of 69 patients were above 120 degrees. CONCLUSIONS: Ceramic on ceramic bearing showed an encouraging result in Crowe IV DDH total hip arthroplasty.

[Clinical observation on the treatment of periprosthetic infection of coagulase-negative staphylococci by two-stage revision].

OBJECTIVE: To investigate the risk factors for the failure in treating periprosthetic infection of coagulase-negative staphylococci by two-stage revision. METHODS: From January 2005 to June 2015, 57 patients with periprosthetic hip and knee joint infection of coagulase-negative staphylococcus by two-stage revision were retrospectively reviewed with an average age of (61.3±11.9) years old. According to the drug resistance of methicillin, the patients were divided into methicillin sensitive group(MSCoN) and methicillin resistance(MRCoN) group, 25 cases in MSCoN group(9 knees and 16 hips) included 12 males and 13 females, 32 cases in MRCoN group(11 knees and 21 hips) included 14 males and 18 females. Follow-up for at least 2 years, the inflammatory markers, incidence rate of sinus and the duration of the symptoms, reinfection or persistent infection rate after two-stage revision were compared between two groups. RESULTS: MSCoN group and MRCoN group were followed up(81.7±38.3) months and(65.9±33.8) months, respectively;23 cases and 27 cases were successfully treated;there was no significant difference between two groups(P=0.643). The patients who had surgery history were 4.04 times higher of failure than the patients without a history of surgery[OR=4.04, 95%CI(0.62, 26.5)]. Patients who had sinus were 4.26 times higher of failure than the patients without sinus[OR=4.26, 95%CI(0.7, 25.9)]. CONCLUSIONS: Two-stage revision is an effective procedure in treating patients infected by MSCoN and MRCoN. There is no significant difference of treatment failure rate between MSCoN and MRCoN group by two-stage revision. Surgery history and sinus maybe the risk factors of treatment failure, while methicillin-resistance is not.

[Mechanical complications with self-made, antibiotic-loaded cement articulating spacers in the treatment of the infected hip replacement].

OBJECTIVE: To study the complications and efficacy of self-made, antibiotic-loaded cement articulating spacers in the treatment of the infected hip replacement. METHODS: Between January 2006 and July 2016, 265 patients (266 hips) received a self-made, antibiotic-loaded cement articulating spacer as part of a two-stage protocol. Among those patients, there were 143 males(144 hips) and 122 females(122 hips). The cement articulating spacers with vancomycin and two Steinman pins were made by a self-made mold system. Meanwhile, another antibiotic was added to the spacers according to the drug sensitivity test. Record if the infected prosthesis was removed, related complication with spacer(breakage and dislocation), Harris score, and control rate of infection. RESULTS: The mean age of two-stage revision operation was(57.4±14.2) years. Thirty-nine patients(14.7%) used extended trochanteric osteotomy(ETO) to remove the infected prosthesis. And 38 patients occurred mentioned complications(14.3%). Spacer breakage occurred in 28 cases(10.5%) and dislocation occurred in 10 cases(3.8%). The mean follow-up time was(83.4±14.6) months. The Harris hip score was from 47.56±14.23 preoperatively to 86.43±12.84 at final follow-up(P<0.05). The infection of 256 cases(96.6%) got control after revision operation. However, during postoperative follow-up, 4 cases occurred re-infection, and they were reoperated, and the infections obtained effective control after the operation. Thus total infection control rate was 95.1%(252/265). CONCLUSIONS: Antibiotic-loaded cement articulating spacer made by a self-made mold system is effective in controling infection caused by hip replacement. Related complication is less with spacer by a mould enclosing two Steinman pins. Using metallic internal fixation or allograft bone combined with spacer does not affect infection control.

[Clinical results in early and mid term of using the S-ROM femoral stem in revision].

OBJECTIVE: To investigate and the clinical effect of S-ROM modular stem in femur reconstruction in hip revision arthroplasty. METHODS: From January 2008 to January 2016, 21 patients received revision hip arthroplasties using S-ROM stems. There were 5 males and 16 females with an average of 48.33 years old(range, 29 to 73 years old). There were 13 cases caused by aseptic loosening, 4 cases by infection, 2 cases by nonunion of sub-tuberosity osteotomy, 1 case for repeated dislocation, 1 case for traumatic great trochanter fracture. Primary THA reasons:12 cases for DDH(9 cases for Crowe IV), 5 cases for femoral neck fracture, 2 cases for necrosis of femoral head, 2 cases for proximal femoral deformity caused by early infection. The femur bone defects included Paprosky II in 11 cases, IIIa in 9, and IIIb in 1. Harris hip score , pain score and hip flexion were recorded before and after operation. The subjective satisfaction was recorded at the last follow-up. RESULTS: The operation time and blood loss were 189 min(125 to 290 min) and 867 ml (200 to 2 000 ml). At the final followup, the pain score improved from (17.14±9.56) points preoperatively to (41.71±2.03) points (t=11.42, P=0.00). The function score improved from (24.01±11.02) points preoperatively to (49.95±5.38) points (t=9.73, P=0.00). Harris hip score improved from (41.15±14.81) points preoperatively to(91.67±5.83) points(t=15.33, P=0.00). The degree of hip flexion increased from (93.10±27.27) points preoperatively to (121.90±16.62) points at the last follow-up (t=4.59, P=0.00). The mean subjective satisfaction was 9.48(10 points system), 14 of which were completely satisfactory. The last follow-up hip X-ray showed 21 cases of bone ingrowth, and other femoral stem without loosening or sinking sign significantly. There were 5 cases with bone anchor syndrome around proximal femoral cuff. There were 5 cases of proximal femur fracture, 3 cases of lesser trochanter fracture, 2 cases of greater trochanter fracture intra-operatively. Due to femoral canal stenosis, there were 4 cases of pre-tied wire at lesser trochanter to prevent fractures. There was 1 case of traumatic femoral fracture around stems with a distal oblique fracture, open reduction and locking plate fixation was performed. Other patients had no nerve stretch injury, dislocation, infection and lower limb deep vein thrombosis and other complications at the final follow-up. CONCLUSIONS: S-ROM prosthesis has satisfactory results in hip revision arthroplasty with Paprosky II and III femoral defects. Especially for patients with Crowe IV DDH and other proximal femoral deformities, it is possible to adapt to the medullary cavity morphology. Excellent initial stability, less complications and long-term biological fixation can be achieved with S-ROM in femur revision.