Finite element analysis of the mechanical strength of a new hip Spacer.

BACKGROUND AND OBJECTIVE: At present, the influence of the internal metallic endoskeleton of Spacer on the biomechanical strength of Spacer remains unclear. The aim of this study was to analyze the mechanical stability of a novel Spacer applying a annular skeleton that mimics the structure of trabecular bone using finite element methods. METHEDS: The femur models of three healthy individuals and skeletonless Spacer, K-Spacer, and AD-Spacer were assembled to create 15 3D models. Finite element analysis was performed in an Ansys Bench2022R1. Biomechanical parameters such as stress and strain of the Spacer, internal skeleton and femur were evaluated under three loads, which were applied with the maximum force borne by the hip joint (2100 N), standing on one leg (700 N), and standing on two legs (350 N). The mechanical properties of the new hip Spacer were evaluated. RESULT: The stresses on the medial and lateral surfaces of the AD-Spacer and K-Spacer were smaller than the stresses in the state without skeletal support. The maximum stresses on the medial and lateral surfaces of the AD-Spacer were smaller than those of the inserted K-Spacer, and the difference gradually increased with the increase of force intensity. When the skeleton diameter was increased from 3 to 4 mm, the stresses in the medial and lateral sides of the AD-Spacer and K-Spacer necks decreased. The stress of both skeletons was concentrated at the neck, but the stress of the annular skeleton was evenly distributed on the medial and lateral sides of the skeleton. The mean stress in the proximal femur was higher in femurs with K-Spacer than in femurs with AD-Spacer. CONCLUSIONS: AD-Spacer has lower stress and higher load-bearing capacity than K-Spacer, and the advantages of AD-Spacer are more obvious under the maximum load state of hip joint.

The potential performance of serum albumin to globulin ratio, albumin and globulin in the diagnosis of periprosthetic joint infection and prediction of reinfection following reimplantation.

BACKGROUND: This study was conducted to evaluate the performance of serum albumin (ALB), globulin (GLO), and albumin to globulin ratio (AGR) in the diagnosis of PJI and prediction of reinfection following reimplantation in PJI patients who underwent two-stage revision. METHODS: We perform a retrospective data collection on identified patients who underwent revision arthroplasties in our institution from January 2010 to January 2020. A total of 241 patients were stratified into: group A (PJI), group B (aseptic loosening). Fifty-five patients who underwent two-stage revision in group A were assigned to group C. Group C was stratified into subgroup 1 (reinfection) and subgroup 2 (non-reinfection). Receiver operating characteristic curves were used to evaluate the utility of serum markers for diagnosing PJI and predicting reinfection following reimplantation. RESULTS: In the diagnosis of PJI, there were significant differences in the levels of ALB, GLO, and AGR between groups A and group B (P < 0.05). The AUC value of serum AGR (0.851) was similar to ESR (0.841) and CRP (0.866) (all p > 0.05). The AUC values of serum ALB and GLO were 0.757 and 0.753, respectively. As for predicting reinfection following reimplantation, the serum ALB in the non-reinfection group was higher than that in the reinfection group (p = 0.041). The AUC value of serum ALB was 0.7. CONCLUSION: AGR was promising adjunct marker for the diagnosis of PJI, similar to CRP and ESR. ALB and GLO have an acceptable value for the diagnosis of PJI. ALB may be expected to be a kind of effective marker for predicting reinfection following reimplantation.

The effect of posterior capsule repair in total hip arthroplasty: a systematic review and meta-analysis.

BACKGROUND: Prior studies have compared the posterior capsule repair group in primary total hip arthroplasty by posterior approach with the control group without posterior capsule repair suggesting that the posterior capsule repair group had better clinical outcomes. However, it is still a controversy which treatment is more helpful for hip diseases. The purpose of our article is to obtain the postoperative outcomes between the 2 procedures. METHODS: We performed a systematic search by browsing the MEDLINE, EMBASE, Cochrane Library. There is no restriction on the date of publication. Before we submit our manuscript, we have re-searched the literatures again, including the articles which directly compared the postoperative outcomes of the 2 procedures. RESULTS: A total of 8 comparative studies were included in our meta-analysis. The posterior capsule repair group showed less dislocation rate, higher HHS, and even less postoperative bleeding volume. Meanwhile, there is no significant difference in ROM between 2 groups. CONCLUSION: In conclusion, according to current evidences, repairing posterior capsule during primary THA may have better functional outcomes, less dislocation incidence, and less loss of blood.

Total Calcanectomy and Bilateral Iliac Bone Autograft Reconstruction for the Treatment of Calcaneal Chondroblastoma Involving a Secondary Aneurysmal Bone Cyst: A Case Report and Literature Review.

Chondroblastoma is a rare, benign, cartilaginous-derived tumor accounting for ∼1% to 2% of all primary bone tumors and almost 9% of all benign bone tumors. In this case report, we describe a patient with chondroblastoma and a secondary aneurysmal bone cyst, with the adjacent talus being mildly affected. The initial diagnosis was giant cell tumor and was then confirmed after computed tomography-assisted biopsy. We performed a total calcanectomy via bilateral structural iliac bone autografting to relieve pain and reconstruct the loadbearing function because of the presence of extensive lesions. The patient was pain free and expressed satisfaction with postsurgical dorsiflexion and plantarflexion function at the 60-month follow-up visit. Radiographic images showed that the autografted iliac bone was completely healed, with no evidence of local recurrence.

A comparative study of cortico-cancellous iliac bone graft with or without the combination of vascularized greater trochanter flap for the management of femoral head osteonecrosis: a minimum 6 years follow-up.

BACKGROUND: To compare the mid-long-term clinical and radiological outcomes between a combination of cortico-cancellous iliac bone graft with vascularized greater trochanter flap (Group A) and isolate iliac bone graft (Group B) in the treatment of Osteonecrosis of the Femoral Head (ONFH). METHODS: From January 2006 to December 2012, 123 patients (135 hips) who underwent abovementioned hip-preserving surgeries were included for analysis. Clinical outcomes were assessed based on Harris Hip Score (HHS) System and The Western Ontario and McMaster University Index (WOMAC) scores between the preoperative and the last follow-up. A series of postoperative X-rays were compared to preoperative images for radiological evaluation. RESULTS: The HHS in Group A and B were enhanced from 50.57 ± 3.39 to 87.60 ± 4.15 and from 50.24 ± 3.30 to 85.18 ± 6.45, respectively, which both showed significance between preoperative and postoperative latest follow-up (p < 0.001). Group A revealed better improvement in terms of HHS (p = 0.017). The WOMAC total, postoperative stiffness, difficulty subscale scores in Group A showed better outcomes when compared to Group B (p < 0.01), while pain improvement between these two groups revealed no significance (p = 0.402). Besides, Group A suggested better necrotic region repair (p = 0.020), but no femoral head collapse difference in terms of Association Research Circulation Osseous classification change was found (p > 0.05). CONCLUSIONS: A combination of cortico-cancellous iliac bone graft and concurrent vascularized greater trochanter flap with the lateral femoral circumflex transverse branch has been proved can obtain better functional and radiological results than isolate iliac bone grafting, which is attributed to blood reconstruction of the femoral head.

One-sided hip-preserving and concurrent contralateral total hip arthroplasty for the treatment of bilateral osteonecrosis of the femoral head in different stages: short-medium term outcomes.

BACKGROUND: We aimed to evaluate the clinical and radiological short-medium term outcomes for the treatment of bilateral osteonecrosis of the femoral head (ONFH) with hip-preserving surgery of core decompression followed by tightly impaction bone grafting combining with non-vascularized fibular allografting in one hip and concurrent one-stage total hip arthroplasty (THA) in the contralateral side. We hypothesized the aforementioned surgery showed benefits of protecting the preserved hip from collapsing and thereafter THA was delayed or avoided. METHODS: We retrospectively reviewed a consecutive series of 18 non-traumatic bilateral ONFH patients (36 hips) who had undergone previous mentioned surgeries between July 2004 and June 2013. Preoperative and the last follow-up Harris Hip Score (HHS) and Visual Analogue Scale (VAS) Score were obtained for clinical outcomes evaluation and X-rays of antero-posterior and frog-leg lateral views of bilateral hips were compared for radiological outcomes assessment. RESULTS: All patients were telephone contacted for out-patient clinic return visit at an average follow-up time of 53.3 months (ranged from 20 months to 107 months). Of the 18 patients (15 men and 3 women), there were 5 patients were diagnosed preoperative IIB stages according to classification of the Association Research Circulation Osseuse classification (ARCO) and the remaining 13 patients were in ARCO IIIC stages. The mean age of the included patients was 40.7 years (range from 22 to 59 years). No age and followed-up time difference existed in genders. The postoperative HHS were 83.8 ± 17.9 points, and it revealed statistical significance when compared to preoperative 61.6 ± 17.0 points (p < 0.05). The VAS scores were reduced from preoperative 6.2 ± 2.0 points to postoperative 2.8 ± 2.3 points, which also manifested outcomes significance (p < 0.05). From radiological aspects, 14 patients acquired well repairmen of the necrotic areas of the femoral head. However, the other 4 patients ultimately suffered femoral head collapse, and the severe pain was gotten rid of after THA surgeries were performed. CONCLUSIONS: The un-collapsed hip can achieve biological stability and sufficient blood supply through the hip-preserving surgery and obtain longtime repairmen of the necrotic bone as well as early non-weight-bearing function training, which benefits from distributing the whole body weight load to the hip of one-stage THA. Consequently, we recommend this sort of surgery for clinical practice trial when faced bilateral ONFH in different stages though longer time follow-up and larger samples are essentially needed to address its efficacy.

A prospective study concerning the relationship between metal allergy and post-operative pain following total hip and knee arthroplasty.

PURPOSE: A prospective study was conducted to detect whether a relationship exists between metal allergy and post-operative pain in total hip and knee arthroplasty patients. We postulated that to some extent a relationship does exist between them. MATERIALS AND METHODS: Patients who had undergone total hip and knee arthroplasty surgery because of hip and knee disease were included. The exclusion criteria were patients who were treated with immunosuppressor two weeks pre-operatively, skin conditions around the patch testing site, and other uncontrollable factors. Each patient agreed to patch testing for three days before surgery. Photographic images before patch testing, two and three days after patch testing were obtained to evaluate the final incidence of metal allergy. The patch tests contained 12 metal elements; chromium, cobalt, nickel, molybdenum, titanium, aluminium, vanadium, iron, manganese, tin, zirconium, and copper. Two independent observers evaluated the images. The results were divided into a non-metal allergy group and a metal allergy group. Pre-operative and postoperative VAS score, lymphocyte transforming test, and X-rays were collected to detect the relationship between metal allergy and post-operative pain following total hip and knee arthroplasty. RESULTS: There were 96 patients who underwent pre-operative patch testing. The overall metal allergy rate was 51.1% (49/96) in our study. Nickel, cobalt, manganese, and tin were the most common allergic metal elements in our study. Nine inappropriate cases were excluded, and 87 patients were finally included in our study. There were 36 metal allergy and 26 non-metal allergy patients in the THA group, while 11 metal allergy and 14 non-metal allergy patients were found in the TKA group. We found no relationship existed between metal allergy and post-surgery pain in total hip and knee arthroplasty. CONCLUSION: Pain caused by metal allergy usually presents as persistent and recurrent pain. The white cell count, C-reactive protein, erythrocyte sedimentation rate and postoperative radiographs were not affected. Currently, patch testing and lymphocyte transforming tests are used for metal allergy diagnosis. We deemed that a relationship between post-surgery pain and metal allergy in total hip and knee patients may exist to some extent. Larger samples and longer follow-up time are essential for further study.

Bone Healing and Clinical Outcome Following Medial Opening-wedge High Tibial Osteotomy Using Wedge-Shaped Cancellous Allograft.

OBJECTIVE: Medial opening-wedge high tibial osteotomy (MOWHTO) is considered to be an effective treatment for symptomatic knee osteoarthritis (KOA) of isolated the medial compartment with varus alignment of the lower extremity. However, the choice of material to fill the void remains controversial. This study aims to evaluate the bone union of the osteotomy gap using a novel wedge-shaped cancellous allograft after MOWHTO and its effect on clinical outcomes. METHODS: All patients who underwent MOWHTO using a novel wedge-shaped cancellous allograft combined with TomoFix locking compression plate (LCP) fixation between January 2016 and July 2020 were enrolled. The radiographic parameters including hip-knee-ankle angle (HKAA), medial proximal tibial angle (MPTA), femorotibial angle (FTA) and posterior tibial slope angle (PTSA) were measured between pre-operative and post-operative radiographs. Knee Society score (KSS) and range of motion (ROM) were assessed preoperatively and at last follow-up. Patients included in this study were divided into two groups according to the correction angle: small correction group (< 10°; SC group) and large correction group (≥ 10°; LC group). The modified Radiographic Union score for tibial fractures (mRUST) was used to assess the difference in bone healing between the two groups at 1, 3, 6, and 12 months postoperatively and at the final follow-up. A paired student's t test was conducted for comparison of differences of the relevant data pre-operatively and post-operatively. RESULTS: A total of 82 patients (88 knees) were included in this study. The HKAA, MPTA, FTA and PTSA increased from -6.4° ± 3.0°, 85.1° ± 2.6°, 180.1° ± 3.2° and 7.7° ± 4.4° preoperatively to 1.2° ± 4.3° (p < 0.001), 94.4° ± 3.3° (p < 0.001), 171.0° ± 2.8° and 11.8° ± 5.8° (p < 0.001) immediately postoperatively, respectively. However, no significant statistic difference was found in above-mentioned parameters at last follow-up compared to immediate postoperative data (p > 0.05). All patients in this study achieved good bone healing at the final follow-up and no significant differences in mRUST scores were seen between the SC group and LC group. The KSS-Knee score and KSS-Function score improved significantly from 55.4 ± 3.7 and 63.3 ± 4.6 preoperatively to 86.4 ± 2.8 (p < 0.001) and 89.6 ± 2.9 (p < 0.001) at last follow-up, respectively. Nevertheless, there was no significant difference in ROM between pre-operation and last follow-up (p > 0.05). CONCLUSION: For MOWHTO, the wedge-shaped cancellous allograft was a reliable choice for providing good bone healing and clinical outcomes.

Vascularised greater trochanter bone graft, combined free iliac flap and impaction bone grafting for osteonecrosis of the femoral head.

PURPOSE: To investigate the curative efficacy of osteonecrosis of the femoral head (ONFH) in a hip-preserving operative approach, by grafting a vascularized greater trochanter flap combined with a free iliac flap, in an attempt to seek an innovative approach for patients who suffered middle to late stage ONFH without total hip arthroplasty (THA) surgery. METHOD: Our research included a total of 60 patients (66 hips) who accepted hip-preserving surgery by grafting a vascularized greater trochanter flap combined with a free iliac flap which was tightly filled by hammering because of ONFH (most were Association Research Circulation Osseous (ARCO) stage III patients) from January, 2006 to December, 2010. A Harris Hip Score was obtained during follow-ups, evaluating the clinical efficacy, X-rays were taken regularly for image assessing, and the SF-36 scale was used for estimating quality of life. Terminal observation time was considered when patients had symptom-dependant indications for performing another hip-preserving surgery or THA surgery. RESULTS: Fifty-eight patients (64 hips) were eventually contacted by telephone for an out-patient clinic return visit, with a mean follow-up time of 35.8 months (varied from 12 months to 60 months), but two patients lost contact for various reasons. The demographic data were as follows: there were 16 ARCO IIIA cases, 22 ARCO IIIB cases, and 26 ARCO IIIC cases, respectively. Postoperative X-rays revealed a well-repaired necrotic area of the femoral head and improvement of femoral-acetabulum coverage. The last follow-up mean Harris Hip Score was 86.56 ± 7.38 (excellent results reached 87.50%), which were greatly improved compared to 50.95 ± 6.86 pre-operatively. Also the postoperative mean scores of all dimensions of the SF-36 scale were improved to some extent. Additionally the physical component summary (PSC) scores were enhanced from 42 ± 13 pre-operatively to 78 ± 11, while the postoperative mental component summary (MCS) scores (76 ± 11) largely increased in contrast to pre-operative scores (51 ± 10), with both target indices having statistical significance (p = 0.005, p = 0.01), signifying hugely improvement of the quality of life of the patients. A correlation was found between Harris Hip Score and all dimensions of SF-36 scale (r = 0.32-0.72), especially closely correlated with physical functioning (PF), role-physical (RP) and bodily pain (BP) in PCS aspect (r = 0.72, p < 0.01; r = 0.58, p < 0.01; r = 0.65, p < 0.01, respectively). CONCLUSION: There is definite curative efficacy for the treatment of ONFH with an hip-preserving operative approach by grafting a vascularized greater trochanter flap combined with a free iliac flap which was tightly filled by hammering. This kind of operative approach reconstructs the biological stability of femoral head, which promotes repair of necrotic areas and indirectly preserves the femoral head of patients and a majority of hip function. It possesses vast clinical as well as practical significance, because the long-term efficacy can satisfy fundamental life requirements, especially for those young and middle-aged patients who suffer ONFH to avoid or put off the time of total hip arthroplasty (THA) surgery.

What is the difference in proprioception between single condylar arthroplasty and high tibial osteotomy? a comparative study on both knees of the same patient.

OBJECTIVE: This study aims to investigate the efficacy and outcomes of different surgical procedures, namely unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO), for the treatment of bilateral medial compartment knee osteoarthritis in the same patient. The joint awareness and function of these two surgical methods were evaluated. METHODS: A total of 15 patients with bilateral medial compartment knee osteoarthritis who underwent either UKA or HTO between 2012 and 2020 were included in the study. Patient data, including age, gender, body mass index and length of hospital stay, were collected. Pre- and post-operative measurements were conducted, including tibiofemoral angle, tibial plateau posterior inclination angle, proximal tibial medial angle, distance from mechanical axis to knee joint center, hip-knee-ankle angle, pre- and post-operative knee joint scores, knee joint range of motion, and FIS-12 scores at 3, 6, 12, and 24 months postoperatively. The latest follow-up was used for evaluating the outcomes of osteoarthritis treatment. Normality of continuous variables was assessed using the Shapiro-Wilk test. Between-group comparisons were performed using the paired sample t-test or Wilcoxon rank-sum test. Repeated measures analysis of variance was utilized to analyze FJS-12 measurements at different time points, and the correlation between FJS-12 and postoperative clinical results was examined using Pearson's correlation coefficient. Statistical significance was set at P < 0.05. RESULTS: Significant differences were observed in FJS between the UKA and HTO groups at 3 and 6 months postoperatively, but no significant difference was found at 1 and 2 years postoperatively. FJS in the UKA group demonstrated a significant increase from 3 to 6 months postoperatively, but no significant difference was observed from 6 to 24 months postoperatively. In contrast, FJS in the HTO group showed a significant increase from 3 to 24 months postoperatively. CONCLUSIONS: Patients who underwent UKA exhibited superior joint awareness compared to those who underwent HTO during the early postoperative period. Furthermore, the rate of joint awareness in UKA patients was faster than in HTO patients.

Predictors and complications of blood transfusion in rheumatoid arthritis patients undergoing total joint arthroplasty.

PURPOSE: Our research investigated predictors of postoperative blood transfusion rate following total joint arthroplasty (TJA) in patients with rheumatoid arthritis (RA) and evaluated the incidence of complications in the transfusion group and non-transfusion group. METHODS: The authors retrospectively analyzed risk factors among 320 RA patients who underwent elective total hip arthroplasty (THA) or total knee arthroplasty (TKA) from January 2010 to December 2018. Demographic characteristics, laboratory results, medication history, and surgical protocol were gathered from electronic medical records. Univariable and multivariable logistic regression analyses were conducted to measure the impact of relevant variables on the need for transfusions. In addition, we compared the incidence of complications associated with transfusion. RESULTS: The cohort comprised 320 RA patients, aged 57.4 ± 12.0 years, of whom 137 required postoperative blood transfusions and 183 did not. BMI, type of surgery, duration of surgery, disease activity score 28 (DAS28-CRP), tranexamic acid (TXA) administration, and preoperative hemoglobin (Hb) were all risk factors for transfusion after adjusting for the planned procedure. CONCLUSION: Previously published predictors, such as BMI, low preoperative hemoglobin, duration of surgery, procedure type (THA), were also identified in our analysis. Moreover, TXA administration and the DAS28-CRP showed the potential to influence risk. The incidence of postoperative complications was increased in patients who received blood transfusions compared to non-transfusion group. Our findings could help to identify RA patient population requiring blood transfusions, to ensure the necessary steps are adopted to limit blood loss and improve blood management strategies. Key Points • The risk factors for blood transfusion in rheumatoid arthritis patients undergoing total joint arthroplasty were BMI, the type of surgery, duration of surgery, TXA administration, DAS28-CRP, and preoperative hemoglobin. • The incidence of postoperative complications was increased in patients who received blood transfusions compared to non-transfusion group.

Diagnostic accuracy of sonication fluid cultures from prosthetic components in periprosthetic joint infection: an updated diagnostic meta-analysis.

BACKGROUND: Periprosthetic joint infection (PJI) is the most serious complication following total joint arthroplasty (TJA) and has a significant impact on patients and the national healthcare system. To date, the diagnosis of PJI is still confronted with dilemmas. The present study investigated the validity of sonication fluid culture (SFC) for removing implants in the diagnosis of PJI after joint replacement. METHODS: From database establishment to December 2020, relevant literature was retrieved from the PubMed, Web of Science, Embase and Cochrane Library databases. Two reviewers independently performed quality assessment and data extraction to calculate the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), area under the curve (AUC) and diagnostic odds ratio (DOR) to evaluate the diagnostic value of overall SFC for PJI. RESULTS: A total of 38 eligible studies including 6302 patients were selected in this study. The pooled sensitivity, specificity, PLR, NLR, and DOR of SFC for PJI diagnosis were 0.77 (95% confidence interval [CI], 0.76-0.79), 0.96 (95% CI, 0.95-0.96), 18.68 (95% CI, 11.92-29.28), 0.24 (95% CI, 0.21-0.29), and 85.65 (95% CI, 56.46-129.94), respectively, while the AUC was 0.92. CONCLUSION: This meta-analysis showed that SFC was of great value in PJI diagnosis, and the evidence of SFC on PJI was more favorable but not yet strong. Therefore, improvement of the diagnostic accuracy of SFC is still necessary, and the diagnosis of PJI continues to warrant a multiplex approach before and during a revision procedure.

Research Status and Hotspots of Chronic Osteomyelitis: A Bibliometric and Visualized Analysis.

OBJECTIVE: The treatment of chronic osteomyelitis (COM) is extremely challenging for physicians and patients. It is of great significance to explore the research status, development trend and future research hotspots in the field of COM to promote the development of this field. This study is aimed to explore the global research status of COM and predict its future research hotspots based on bibliometric and visualized analysis. METHODS: Web of Science core collection database was used to search the related literature of COM from 1994 to 2020. All data were imported into Microsoft Excel 2019 for collation. Additionally, the literature quality of countries, authors, journals, and institutions is evaluated. The VOS viewer software was used for conducting co-analysis, co-citation analysis, and keyword co-occurrence analysis of literature to analyze the global status and predict the future hotspots of the COM field. RESULTS: A total of 726 articles were retrieved in this study. The number of global publications shows a trend of wave growth, but the increase is not significant. It is expected that the number of COM articles will remain at more than 50 per year in the next decade. The COM literature published in the United States (Publications = 160, H index = 37, average citations per item = 28.63) is of the highest quality. Girschick HJ (Publications = 16, H index = 14, average citations per item = 52.25) is the most contributed scholar in the field of COM. UNIV IOWA (Publications = 15, H index = 11, average citations per item = 57.27) and UNIV WURZBURG (Publications = 18, H index = 15, average citations per item = 47.5) are influential institutions in the field of COM. The results of co-occurrence analysis show that the field of COM can be roughly divided into the following five modules: COM surgical research, COM basic research, COM diagnosis-related research, chronic recurrent multifocal osteomyelitis (CRMO)-related research, risk factors of COM. Risk factors of COM are the module with the highest concentration of hot words. CONCLUSION: COM-related research will continue to develop further in the next decade. The diagnosis research and risk factors of COM are the most popular research modules in recent years. Some controversial or troubled issues including the efficacy of perforator flap and fascia flap covering soft tissue, searching exclusive detection methods for the diagnosis of COM and bisphosphonates and biological agents in the treatment of CRMO may lead to the development of the COM field.

Effect of the amount of correction on posterior tibial slope and patellar height in open-wedge high tibial osteotomy.

Objectives: To evaluate the effect of amount of correction on postoperative changes in PTS (posterior tibial slope), PH (patellar height), and clinical outcomes following biplanar OWHTO (open-wedge high tibial osteotomy). Method: This study included 79 knees (32 left and 47 right) of 79 patients (mean age 60.28 ± 4.2 years, 24 males, 55 females) with varus malalignment and symptomatic isolated medial joint osteoarthritis who underwent OWHTO. According to the amount of correction angles, all patients were divided into three groups: LCA (large correction angle) group (>14°), MCA (medium correction angle) group (10°-14°), and SCA (small correction angle) group (<10°). All patients were clinically assessed according to the Lysholm score, HSS (hospital for special surgery knee score), and KSS (knee society score) prior to and after surgery. For radiographic analysis, we measured the PTS, PH [ISI (Insall-Salvati index), and BPI (Blackburne-Peel index)]. The pre-post difference of PTS, ISI, and BPI was calculated by subtracting the post-OWHTO value to the pre-OWHTO value in three groups, respectively. The preoperative, postoperative, and difference of PTS, ISI, and BPI values were analyzed according to the correction angle. The mean follow-up period was 28.5 months (SD, 4.9; range 18-52 months). Results: Radiologically, PTS increased and PH decreased after surgery on the whole (p < .05). The relationship between amount of correction and slope increase is significant (p < .001). Furthermore, the pairwise difference between the LCA group and SCA group and MCA group is significant respectively (p < .05). In terms of PH, the LCA group yielded ISI and BPI that were significantly different from baseline for the SCA group and MCA group. In addition, the pairwise difference between the SCA group and LCA group in ISI and BPI is significant (p = .031). Clinically, significant improvements were observed in postoperative clinical scores of the Lysholm score, HSS, and KSS (p < .05). Seventy-four patients (93.67%) reported satisfaction with surgery. However, no correlation was found between changes in PTS and PH with postoperative knee score. No severe adverse complications were observed. Conclusions: The amount of correction angle is a significant factor affecting the PTS and PH in OWHTO. With increased correction angle, the likelihood of increasing the PTS and decreasing the PH increases. Special attention should be paid to keep PTS and PH unchanged in cases where large corrections are required. Otherwise, closing wedge osteotomy or other intraoperative effective measures are supposed to be adopted.

Patellofemoral arthroplasty versus total knee arthroplasty for isolated patellofemoral osteoarthritis: a systematic review and meta-analysis.

BACKGROUND: Isolated patellofemoral osteoarthritis (PF-OA) is a common subtype of knee osteoarthritis, leading to a huge economic burden on health care systems. Although previous studies have shown that patellofemoral arthroplasty (PFA) and total knee arthroplasty (TKA) have good clinical effects, it remains largely unclear which treatment is more effective for patients with isolated PF-OA. We aimed to compare postoperative function, complications, revision rates, level of physical activity, and satisfaction rate between the two surgical techniques. METHODS: Our study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Search of literature was conducted in MEDLINE, EMBASE, Cochrane Library, and Web of Science until November 2020. The included studies were those that provided direct comparison of postoperative outcomes between PFA and TKA. Data were extracted from eligible studies and combined to calculate the pooled odds ratio (OR) and 95% confidence interval (CI). Sensitivity analysis and subgroup analysis were conducted to evaluate heterogeneity between the two groups. RESULTS: A total of 7 eligible studies (3 recent randomized controlled trials and 4 nonrandomized controlled trials) were included in this meta-analysis. The pooled results showed that both the PFA group and the TKA group had improved postoperative indicators, suggesting that the two operation modes could improve the knee function and quality of life of patients. Throughout the first 2 years postoperatively, higher activity level, and better functional recovery were observed for PFA compared with TKA in this study; moreover, the differences between the two operation modes were statistically significant (p < 0.05). We found no significant difference in complications, revision rates, and satisfaction rate between the two procedures. CONCLUSION: Although there was no observed difference in the complications, revision rates, and satisfaction rate between PFA and TKA, PFA was superior to TKA in terms of knee function and physical activity in the first 2 years postoperatively. Therefore, PFA is a safe, effective, and less invasive treatment for patients with isolated PF-OA. Our findings are consistent with the systematic review of current evidence that PFA may be more suitable for younger patients with high activity needs. Patient selection is, therefore, thought to be of paramount importance. Individualized surgical plan should be designed according to the patient's age, BMI, KOA site, and activity level and combined with the doctor's personal experience.

Reliability of circulating fibrinogen in the diagnosis of prosthesis-related infections: a systematic review and meta-analysis.

BACKGROUND: Fibrinogen (FIB) has recently been used as a biomarker to diagnose periprosthetic joint infection (PJI), but its reliability is still questionable. The aim of this study was to investigate the accuracy of FIB in the diagnosis of PJI after joint replacement. METHODS: We searched for literatures published in PubMed, EMBASE, and the Cochrane Library from the time of database inception to September 2020 and screened the studies according to the inclusion criteria. Then, we calculated the diagnostic parameters of FIB, including the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), area under the curve (AUC), and diagnostic odds ratio (DOR). In addition, we implemented subgroup analyses to identify the sources of heterogeneity. RESULTS: Seven studies including 1341 patients were selected in our meta-analysis. The pooled sensitivity, specificity, PLR, NLR, and DOR of FIB for PJI diagnosis were 0.78 (95% confidence interval [CI], 0.73-0.82), 0.83 (95% CI, 0.81-0.86), 4.60 (95% CI, 3.30-6.42), 0.24 (95% CI, 0.18-0.34), and 20.13 (95% CI, 14.80-27.36), respectively, while the AUC was 0.896. CONCLUSION: The present study indicated that FIB was a reliable detection method and might be introduced into the diagnostic criteria for PJI. However, more robust studies are still needed to confirm the current findings, because most of the included studies were retrospective and had small sample sizes.

Diagnostic Accuracy of the Synovial Fluid α-Defensin Lateral Flow Test in Periprosthetic Joint Infection: A Meta-analysis.

OBJECTIVES: There is a controversy on the diagnostic reliability and accuracy of synovial fluid α-defensin in periprosthetic joint infection (PJI). We performed this meta-analysis to evaluate the diagnostic accuracy of the α-defensin lateral flow test in PJI. METHODS: PubMed, Embase, and the Cochrane library were systematically searched, and articles (up to January 2020) on the diagnosis of hip and knee PJIs using the α-defensin Synovasure lateral flow test were included. The diagnostic accuracy of the α-defensin lateral flow test in PJI was evaluated using meta-analysis. The pooled sensitivity, specificity, accuracy, positive and negative likelihood ratio, diagnostic odds ratio, and post-test probabilities were calculated. RESULTS: Seventeen studies including 1443 cases were included. Meta-analysis showed the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and a diagnostic odds ratio was 0.83 (95% CI 0.77, 0.88), 0.95 (95% CI 0.93, 0.97), 16.86 (95% CI 11.67, 24.37), 0.17 (95% CI 0.13, 0.24) and 85.30 (95% CI 47.76, 152.35), respectively. The area under the hierarchical summary receiver operating characteristic curve was 0.97 (95% CI 0.95, 0.98). Subgroup analysis also confirmed the high efficiency of α-defensin Synovasure lateral flow test in diagnosing PJIs, irrespective of ethnicity. Fagan's nomogram analysis there was a high positive post-test probability of 94% and a low negative post-test probability of 15%. CONCLUSIONS: We indicated that the α-defensin lateral flow test had a high accuracy for diagnosing PJI. Large-scale studies are needed to validate its significance in PJI diagnosis.

Impact of intraoperative medial collateral ligament injury on outcomes after total knee arthroplasty: a meta-analysis and systematic review.

BACKGROUND: As an uncommon but severe complication, medial collateral ligament (MCL) injury in total knee arthroplasty (TKA) may be significantly under-recognized. We aimed to determine whether MCL injury influences postoperative outcomes of patients undergoing TKA. METHODS: Two independent reviewers searched PubMed, Cochrane Library, and EMBASE from their inception to July 1, 2021. The main outcomes were postoperative function, and secondary outcomes included the incidences of revision and complications. RESULTS: A total of 403 articles yielded 15 studies eligible for inclusion with 10 studies used for meta-analysis. This study found that there was a statistically significant difference in postoperative functional scores, range of motion (ROM), complications, and revision rates, with adverse outcomes occurring more commonly in patients with MCL injury. CONCLUSIONS: This meta-analysis highlights the complexity of MCL injury during TKA and shows the impact on postoperative function, joint mobility, complications, and revision. Surgeons need to prevent and put more emphasis on MCL injury during TKA.

Can nasal Staphylococcus aureus screening and decolonization prior to elective total joint arthroplasty reduce surgical site and prosthesis-related infections? A systematic review and meta-analysis.

BACKGROUND: Nasal Staphylococcus aureus (S. aureus) screening and decolonization has been widely used to reduce surgical site infections (SSIs) prior to total knee and hip arthroplasty (TKA and THA). However, it remains considerably controversial. The aim of this study was to ascertain whether this scheme could reduce SSIs and periprosthetic joint infections (PJIs) following elective primary total joint arthroplasty (TJA). METHODS: A systematic search was performed in MEDLINE, Embase, and the Cochrane Library until October, 2019. Outcomes of interest included SSI, PJI, superficial infection, and different bacterial species that caused infections. Data from eligible studies were then extracted and synthesized. Pooled odds ratios (OR) and 95% confidence intervals (CIs) were calculated. We also performed additional analyses to evaluate whether there were differences in postoperative SSIs caused by S. aureus or other bacteria. RESULTS: Nine studies were included in our meta-analysis. The pooled data elucidated that nasal S. aureus screening and decolonization dramatically mitigated the risk of SSI, PJI, and superficial infection compared to nondecolonization group. The analysis of bacterial species causing infection also showed that the S. aureus infections postoperative were significantly decreased in the decolonization group. However, there was no statistical difference in the SSI caused by other bacteria between the two groups. CONCLUSION: S. aureus screening and decolonization prior to elective primary THA and TKA could significantly decrease the risk of SSI and PJI. However, more robust studies are needed to further evaluate the impact of S. aureus screening and decolonization on infection risk after TJA.

[Advances on treatment of periprosthetic infection and antibiotic delivery system after total hip arthroplasty].

Periprosthetic infection after hip replacement is a clinical catastrophic disease, which often leads to the failure of the prosthesis. It needs the combination of systemic antibiotics to cure the infection, which brings huge burden to doctors and patients. There are strict indications for debridement and one-stage revision of the prosthesis, and few cases meet the requirements. The second revision is still the gold standard for the treatment of periprosthetic infection. It is suitable for all infection conditions and has a high success rate. On the second phase of renovation, the antibiotic sustained release system plays a key role, and the carrier of antibiotic sustained-release system is the focus of current research, including classic bone cement and absorbable biomaterials. Bone cement has strong mechanical strength, but the antibiotic release shows a sharp decline trend; the absorbable biomaterials can continuously release antibiotics with high concentration, but the mechanical strength is poor, so it could not use alone. The combination of bone cement and absorbable biomaterials will be an ideal antibiotic carrier. PMMA is the most commonly used antibiotic carrier, but the antibiotic release concentration is decreased sharply after 24 hours. It will be difficult to control the infection and increase the risk of bacterial resistance if it is lower than the minimum inhibitory concentration. The biodegradable materials can release antibiotics completely, with long release time and high concentration, but low mechanical strength. Antibiotic spacer plays an important role in the control of infection. In the future, how to further extend the antibiotic release time of antibiotic sustained-release system, increase the amount of antibiotic release and maintain the mechanical strength of the material will be studied.