The cementless taper wedge vs. fit-and-fill stem in primary total hip arthroplasty: risk of stem-related complication differs across Dorr types.

INTRODUCTION: The choice between a cementless taper wedge stem and a fit-and-fill stem in total Hip arthroplasty (THA) for various proximal femoral morphological types has not been thoroughly evaluated. This study aimed to compare the risk of stem-related complications between these two stem types in Dorr type A, B, and C femurs. MATERIALS AND METHODS: From January 2015 through April 2021, we retrospectively reviewed 1995 cementless THA procedures. We stratified all procedures into three groups: Dorr type A (N = 360, 18.0%), B (N = 1489, 74.7%) and C (N = 146, 7.3%). The primary outcome domain was stem-related complications, including stem subsidence ≥ 3 mm, intraoperative fracture, periprosthetic fracture and aseptic stem loosening. We performed multivariate regression analysis to compare the risk of stem-related complication between the two stem types. Other factors included age, sex, body mass index, diagnosis, age-adjusted Charlson comorbidity index, stem alignment and canal fill ratio. RESULTS: The incidence of stem-related complications in the taper wedge and fit-and-fill stem groups was 4.4% (N = 15) and 6.5% (N = 107), respectively. Fit-and-fill stems showed an increased risk of stem-related complications (aOR: 9.903, 95% CI: 1.567-62.597) only in Dorr type C femurs. No significant difference in risk was observed in Dorr type A and B femurs. Furthermore, the canal fill ratio at the lesser trochanter, 2 cm and 7 cm below the lesser trochanter, did not exhibit an association with stem-related complications in any Dorr type. CONCLUSIONS: Concerning the risk of stem-related complications, the taper wedge stem was a better choice in Dorr type C femurs. However, there was no difference in risk between the taper wedge stem and fit-and-fill stem in Dorr type A and B femurs.

Culture-negative periprosthetic joint infections: Do we have an issue?

Culture-negative periprosthetic joint infection (PJI) poses a significant challenge in clinical settings. The lack of information on causative organism(s) leads to uncertainties regarding the choice of antimicrobial treatment, which can potentially adversely influence the outcome. Recent advances in molecular-based diagnostic methods have the potential to address the difficulties associated with culture-negative PJIs. These technologies offer a solution to the existing clinical dilemma by providing identification of pathogens and guiding appropriate antimicrobial treatment. In this narrative review, we provide information regarding: 1) incidence and risk factors for culture-negative PJI; 2) the optimal antimicrobial therapy and duration of treatment for culture-negative PJI; 3) outcome comparison between culture-positive and culture-negative PJI; and 4) utilization of novel molecular diagnostic methods in culture-negative PJI, including pathogen identification, and the implementation of an antibiotic stewardship program.

Risk factors for venous thromboembolism after primary total joint arthroplasty: An analysis of 7511 Taiwanese patients.

BACKGROUND: The need for thromboprophylaxis in Asian patients after primary total joint arthroplasty (TJA) remains inconclusive. We aimed to identify the risk factors for venous thromboembolism (VTE) events following primary TJA in a Taiwanese population. METHODS: From January 2010 to December 2019, we studied 7511 patients receiving primary TJA from a single surgeon. We validated the incidence and risk factors for 30- and 90-day symptomatic VTE events, including age, sex, body mass index (BMI), smoking, medical comorbidities, VTE history, presence of varicose veins, total knee arthroplasty (TKA) vs total hip arthroplasty (THA), unilateral vs bilateral procedure and receipt of VTE prophylaxis, transfusion, and length of stay. RESULTS: The incidence of 30- and 90-day symptomatic VTE events was 0.33% and 0.44%, respectively. Multivariate regression analysis showed that BMI ≥30 (adjusted odds ratio (aOR): 4.862, 95% CI, 1.776-13.313), bilateral TJA procedure (aOR: 2.665, 95% CI, 1.000-7.104), and presence of varicose veins (aOR: 9.946, 95% CI, 1.099-90.024) were associated with increased odds of 30-day symptomatic VTE events. Age ≥77 years (aOR, 2.358, 95% CI, 1.034-5.381) and BMI ≥30 (aOR: 2.832, 95% CI, 1.039-7.721) were associated with increased odds of 90-day symptomatic VTE events. CONCLUSION: Age ≥77 years, BMI ≥30, bilateral TJA procedure, or presence of varicose veins may require pharmacological thromboprophylaxis because such patients have a higher risk of VTE after primary TJA.

Safety and Tolerability of Intra-Articular Injection of Adipose-Derived Mesenchymal Stem Cells GXCPC1 in 11 Subjects With Knee Osteoarthritis: A Nonrandomized Pilot Study Without a Control Arm.

The current study aimed to determine the safety profile of intra-articular-injected allogeneic adipose-derived mesenchymal stem cells (ADSCs) GXCPC1 in subjects with knee osteoarthritis (OA) and its preliminary efficacy outcome. The 3 + 3 phase I study was designed with two dose-escalation cohorts: low dose (6.7 × 106 GXCPC1, N = 5) and high dose (4 × 107 GXCPC1, N = 6). The primary endpoint was safety, which was evaluated by recording adverse events throughout the trial; the secondary endpoints included total, pain, stiffness, and function subscales of the Western Ontario and McMaster Universities Arthritis Index (WOMAC), Visual Analogue Scale (VAS) for pain, and 12-Item Short Form (SF-12) health survey questionnaire. The GXCPC1 treatment was found to be safe after 1 year of follow-up with no treatment-related severe adverse events observed. When compared to baseline, subjects in both the low- and high-dose cohorts demonstrated improving trends in pain and knee function after receiving GXCPC1 treatment. Generally, the net change in pain (95% confidence interval (CI) = -7.773 to -2.561t at 12 weeks compared to baseline) and knee function (95% CI = -24.297 to -10.036t at 12 weeks compared to baseline) was better in subjects receiving high-dose GXCPC1. Although this study included a limited number of subjects without a placebo arm, it showed that the intra-articular injection of ADSCs was safe and well-tolerated in subjects with therapeutic alternatives to treat knee OA. However, a larger scale study with an appropriate control would be necessary for clinical efficacy in the following study.

Combination of enoxaparin and low-dose aspirin for thromboprophylaxis in selective patients after primary total joint arthroplasty in a Taiwanese population.

BACKGROUND: The incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) after total joint arthroplasty (TJA) procedures are lower in Asian populations than in Caucasian populations. Therefore, the need for thromboprophylaxis in Asian patients undergoing TJA remains inconclusive. The aim of this study was to validate the clinical outcomes of thromboprophylaxis in selective TJA patients in a Taiwanese population. METHODS: We retrospectively reviewed records of patients who underwent TJA procedures performed by a single-surgeon between January 2010 through December 2019. Patients received thromboprophylaxis with a combination of enoxaparin and low-dose aspirin if they fulfilled any of the following criteria: 1) body mass index >30 (kg/m 2 ), 2) presence of varicose veins, 3) history of DVT or PE, or 4) simultaneous bilateral TJA procedure. We assessed the incidence of DVT and PE, 90-day postoperative complications, length of stay, in-hospital mortality, 30-day and 90-day readmission, and 1-year reoperation. RESULTS: Of the 7511 patients included in this study, 2295 (30.6%) patients received thromboprophylaxis. For patients who received thromboprophylaxis(N = 2295), the incidence of DVT and PE were 0.44% and 0%, respectively. For patients who did not receive thromboprophylaxis (N = 5216), the incidence of DVT and PE was 0.46% and 0.04%, respectively. The overall rates of 90-day postoperative complications (2.3%), 30-day (1.8%) and 90-day readmission (2.3%), and 1-year reoperation (1.1%) were low. CONCLUSION: Providing thromboprophylaxis for selective TJA patients within the Taiwanese population was effective, as indicated by the low incidence of DVT and PE. Complications, such as surgical site infection, should be carefully weighed and managed.

The impact of Charlson Comorbidity Index on surgical complications and reoperations following simultaneous bilateral total knee arthroplasty.

Simultaneous bilateral total knee arthroplasty (TKA) might be associated with higher postoperative morbidity and mortality rates compared with staged bilateral TKA. However, risk factors for surgical complications and reoperations following simultaneous bilateral TKA remain elusive. We conducted this retrospective, single-surgeon case series from 2010 through 2019. A total of 1561 patients who underwent simultaneous bilateral TKA procedures were included. The outcome domains included 30-day and 90-day readmission events for medical or surgical complications and 1-year reoperation events. We performed logistic regression analysis and backward stepwise selection to identify possible risk factors, including age, sex, body mass index, diabetes mellitus (DM), rheumatoid arthritis, American Society of Anesthesiologist (ASA) classification, Charlson Comorbidity Index (CCI), receiving venous thromboembolism (VTE) prophylaxis, or blood transfusion. The overall 30-day, 90-day readmission, and 1-year reoperation rates were 2.11%, 2.88%, and 1.41%, respectively. Higher CCI score (CCI = 4+) was a risk factor for 90-day readmission (aOR: 2.783; 95% CI 0.621-12.465), 90 day readmission for surgical complications (aOR: 10.779; 95% CI 1.444-80.458), and 1 year reoperation (aOR: 4.890; 95% CI 0.846-28.260). Other risk factors included older age, higher ASA level, DM, and receiving VTE prophylaxis. In conclusion, high CCI scores were associated with increased risks of surgical complications and reoperations following simultaneous bilateral TKA procedures.

The safety and cost-analysis of simultaneous versus staged bilateral total knee arthroplasty in a Taiwan population.

BACKGROUND: In patients with advanced osteoarthritis (OA) of the bilateral knees, uncertainty remains as to whether simultaneous bilateral total knee arthroplasty (SiTKA) or staged TKA (StTKA) is the treatment of choice. The purpose of this study was to investigate the safety and relative cost of SiTKA vs StTKA in Taiwan patients. METHODS: Using the Big Data Center of Taipei Veterans General Hospital, we retrospectively reviewed all patients who underwent SiTKA or StTKA due to OA or spontaneous osteonecrosis of the knee from January 2011 to December 2016. We assessed length of stay, transfusion rate, early postoperative complications, 30- and 90-day readmission rate, 1-year reoperation rate, and the indication for reoperation. Furthermore, we analyzed the total cost of the two groups, including reimbursement from the national health insurance (NHI), cost of the procedures, and net income from each case. RESULTS: A total of 2016 patients (1565 SiTKA and 451 StTKA) were included in this study. The two groups had no significant differences in rates of complications, 30- and 90-day readmission, or 1-year reoperation. The length of stay was on average 5.0 days longer for StTKA ( p < 0.01). In terms of cost, all categories of medical costs were significantly lower for SiTKA, while the net hospital income was significantly higher for StTKA. CONCLUSION: SiTKA is a safe and cost-effective surgery. Both SiTKA and StTKA have similar rates of postoperative complications, readmission and reoperation, but SiTKA significantly reduces medical expenses for both the patient and the NHI.

Does the Addition of iPACK Block to Adductor Canal Block Provide Improved Analgesic Effect in Total Knee Arthroplasty? A Systematic Review and Meta-Analysis.

The interspace between popliteal artery and the capsule of posterior knee (iPACK) block was proposed in recent years to relieve posterior knee pain. Since adductor canal block (ACB) and iPACK involve different branches of the sensory nerves, it is theoretically feasible to combine iPACK block and ACB to relief pain after total knee arthroplasty (TKA). We aim to validate the efficacy of adding iPACK block to ACB in the setting of a multimodal pain management protocol following TKA. A comprehensive literature review on Web of Science, Embase, the Cochrane Library, and PubMed was performed. Eight studies (N = 1,056) that compared the efficacy of iPACK block + ACB with ACB alone were included. Primary outcomes consisted of Visual Analogue Scale (VAS) score at rest or during activity at various time points. Secondary outcomes include opioids consumption, walking distance, and length of hospital stay (LOS). Compared to ACB alone, VAS scores at rest (standardized mean difference [SMD]: -1.18; 95% confidence interval [CI]: -2.05 to -0.30) and during activity (SMD: -0.26; 95% CI: -0.49 to -0.03) on the day of surgery were lower in the iPACK block + ACB group. However, the difference did not reach the minimal clinically important difference. Opioids consumption at postoperative 24 hours was lower in the iPACK + ACB group (SMD: -0.295; 95% CI: -0.543 to -0.048). VAS score on postoperative day (POD) 1 and POD2, opioids consumption from 24 to 48 hours, walking distance, and LOS were not different. In conclusion, the addition of iPACK block to ACB in a multimodal pain management protocol can effectively reduce opioids consumption in the early postoperative period. This is a level III, meta-analysis study.

IL-1b in the Secretomes of MSCs Seeded on Human Decellularized Allogeneic Bone Promotes Angiogenesis.

Angiogenesis plays an important role in the development of bone and bone regeneration to provide the required molecules. Mesenchymal stem cells (MSCs) are pluripotent, self-renewing, and spindle-shaped cells, which can differentiate into multiple lineages such as chondrocytes, osteocytes, and adipocytes. MSCs derived from bone marrow (BMMSCs), adipose tissue (ADMSCs), and Wharton's jelly (UCMSCs) are popular in the field of tissue regeneration. MSCs have been proposed that can promote bone regeneration by enhancing vascularization. In this study, the angiogenic potential of secretomes of undifferentiated and osteo-differentiated BMMSCs, ADMSCs, and UCMSCs seeded on human decellularized allogeneic bone were compared. Human umbilical vein endothelial cells (HUVECs) were treated with MSC secretomes. Cell growth, cell migration, and angiogenesis of HUVECs were analyzed by MTT, wound healing, and tube formation assays. Angiogenic gene expression levels of MSCs were evaluated using real-time quantitative PCR. Antibody neutralization was performed to validate the candidate target. Our study demonstrates that the angiogenic gene expression profile is tissue-dependent and the angiogenic ability of secretomes is independent of the state of differentiation. We also explore that IL-1b is important for MSC angiogenic potential. Taken together, this study proves that IL-1b in the secretomes plays a vital role in angiogenesis.

Cementless primary or revision stem in revision hip arthroplasty for aseptic stem loosening with Paprosky type I/II femoral defect?

BACKGROUND: The use of primary or revision stem during revision total hip arthroplasty (THA) for aseptic stem loosening with Paprosky type I/II femoral defect remains controversial. The aim of this study was to compare the outcomes of patients who underwent revision THA with a primary or revision stem. METHODS: We retrospectively reviewed 78 patients who received revision THA for aseptic stem loosening using primary (N = 28) or revision stems (N = 50). The bone defects were classified as Paprosky type I or II. The mean follow-up duration was 72.3 ± 34.7 months. The primary outcome domains included surgical complications and implant failures. The secondary outcome domains included medical complications, 30- and 90-day readmission, and Harris hip score (HHS). RESULTS: The use of revision stem was associated with a higher incidence than primary stem of patient complications (60.0% vs. 32.1%, p = 0.018), including intraoperative femur fracture (28.0% vs. 7.1%, p = 0.029) and greater trochanter fracture (16.0% vs. 0%, p = 0.045). The implant survival rate was comparable between groups. HHS at the final follow-up was similar. CONCLUSION: With a lower risk of surgical complications and a similar rate of mid-term implant survival, cementless primary stem appears superior to revision stem in revision THA for aseptic stem loosening with Paprosky type I/II femoral defect.

Pharmacological thromboprophylaxis as a risk factor for early periprosthetic joint infection following primary total joint arthroplasty.

Venous thromboembolism (VTE) prophylaxis has been suggested for patients who underwent total join arthroplasty (TJA). However, the morbidity of surgical site complications (SSC) and periprosthetic joint infection (PJI) has not been well evaluated. We aimed to evaluate the impact of VTE prophylaxis on the risk of early postoperative SSC and PJI in a Taiwanese population. We retrospectively reviewed 7511 patients who underwent primary TJA performed by a single surgeon from 2010 through 2019. We evaluated the rates of SSC and PJI in the early postoperative period (30-day, 90-day) as well as 1-year reoperations. Multivariate regression analysis was used to identify possible risk factors associated with SSC and PJI, including age, sex, WHO classification of weight status, smoking, diabetes mellitus (DM), rheumatoid arthritis(RA), Charlson comorbidity index (CCI), history of VTE, presence of varicose veins, total knee or hip arthroplasty procedure, unilateral or bilateral procedure, or receiving VTE prophylaxis or blood transfusion. The overall 90-day rates of SSC and PJI were 1.1% (N = 80) and 0.2% (N = 16). VTE prophylaxis was a risk factor for 90-day readmission for SSC (aOR: 1.753, 95% CI 1.081-2.842), 90-day readmission for PJI (aOR: 3.267, 95% CI 1.026-10.402) and all 90-day PJI events (aOR: 3.222, 95% CI 1.200-8.656). Other risk factors included DM, underweight, obesity, bilateral TJA procedure, younger age, male sex and RA. Pharmacological thromboprophylaxis appears to be a modifiable risk factor for SSC and PJI in the early postoperative period. The increased infection risk should be carefully weighed in patients who received pharmacological VTE prophylaxis.

Is there a role for cementless primary stem in hip arthroplasty for early or late fixation failures of intertrochanteric fractures?

BACKGROUND: The choice of femur stems during the hip arthroplasty procedures for patients with treatment failure of intertrochanteric fractures (ITF) remains controversial. We aimed to compare the surgical complication and reoperation rates between cementless primary and revision stems in the early (≤3 months) and late (> 3 months) fixation failures of ITF. METHODS: This was a retrospective, cohort study conducted in a single, tertiary referral hospital of Taipei, Taiwan. We included hip arthroplasty procedures for failed ITF using cementless primary or revision stems. There were 40 and 35 patients who had early and late fixation failure of ITF, respectively. The patient demographics, time to fixation failure, surgical complications and medical complications were recorded for analysis. RESULTS: We included 75 patients that underwent hip arthroplasty procedure for failed ITF using cementless primary (n = 38) or revision (n = 37) stems. The mean age was 79.3 years and 56% of the patients were female. In the early fixation failure group, the complication rate was similar between the primary and revision stems (44% vs. 29%, p = 0.343). However, there was a trend toward a higher reoperation rate (31% vs. 8%, p = 0.061) of using the primary stem, compared with the revision stem. In the late fixation failure group, the rate of complication and reoperation was similar between the two stem types. CONCLUSION: For early fixation failures of ITFs, we caution against the use of cementless primary stems due to a trend towards an increased risk of reoperations compared to the use of cementless revision stems. However, in late fixation failures of ITFs, there is a role for cementless primary stems. LEVEL OF EVIDENCE: III, retrospective cohort study.

Total knee replacement for patients with severe hemophilic arthropathy in Taiwan: A nationwide population-based retrospective study.

BACKGROUND: Total knee replacement (TKR) surgery is a treatment option for advanced hemophilic arthropathy. Due to its rarity and complexity, previous reports could only demonstrate the results of single-site studies including few cases. This population-based study aimed to investigate the major epidemiological characteristics, mean consumption of coagulation factors, length of hospital stays, complications, and failure rate of primary TKR for severe hemophilia patients in Taiwan. METHODS: A cohort of 996 hemophilia patients registered between 1995 and 2011 was included, and 103 primary TKRs were performed on 75 patients. Unilateral TKR was performed on 47 patients and bilateral TKRs on the remaining 28 patients, including 12 simultaneous and 16 staged surgeries. The mean age at surgery was 32.3 years (range, 17.3-55.7), and the mean follow-up duration was 77.9 months (range, 2.3-176.8). RESULTS: Failure was noted in 8 patients (8.5%) at mean 32.8 months (range, 2.3-95) after surgery. Four patients revealed aseptic loosening, whereas infection in 4. The 10-year prosthesis survivorship was 88.6%. For patients receiving unilateral TKR, the mean length of hospital stay was 15 days (range, 7-32). The mean cost of factor supplement was United States Dollar (USD) 43 543 with a mean 4-unit packed red blood cells transfusion (range, 0-38). The total admission cost was USD 48 326 (range, USD 4165-262 619). CONCLUSION: The prevalence of TKA for hemophilia patients was 7.5% in Taiwan. The mean hospital stay was 14 days, and the 10-year prosthesis survivorship was 88.6%. The mean daily factor usage was decreased from 235.7 units preoperatively to 202.1 units postoperatively. In comparison with the staged-bilateral TKRs, the simultaneous procedures significantly reduced the mean total cost from USD 101 923 to USD 61 587 (p = 0.023). Therefore, in terms of cost-effectiveness, bilateral simultaneous TKR is more preferable than staged procedures.

Dialysis patients have comparable results to patients who have received kidney transplant after total joint arthroplasty: a systematic review and meta-analysis.

Patients with end-stage renal disease (ESRD) have inferior outcomes after hip and knee total joint arthroplasty (TJA), with higher risk for surgical site complications (SSC) and periprosthetic joint infection (PJI).We conducted a systematic review and meta-analysis regarding outcomes after hip and knee TJA in ESRD patients who have received dialysis or a kidney transplant (KT) using PubMed, MEDLINE, Cochrane Reviews, and Embase in order to: (1) determine the mortality and infection rate of TJA in patients receiving dialysis or KT and (2) to identify risk factors associated with the outcome.We included 22 studies and 9384 patients (dialysis, n = 8921, KT, n = 463). The overall mortality rate was 14.9% and was slightly higher in KT patients (dialysis vs. KT, 13.8% vs. 15.8%). The overall SSC rate was 3.4%, while dialysis and KT patients each had an incidence of 3.3% and 3.6%, respectively. For PJI, the overall rate was 3.9%, while the incidence for dialysis patients was 4.0% and for KT patients was 3.7%.Using multi-regression analysis, age, sex, the type of arthroplasty (knee or hip) performed, and the form of renal replacement therapy (dialysis or KT) were not significant risk factors.In patients on dialysis or who had received a KT, TJA is associated with a slight increase in mortality, SSC and PJI rates. Cite this article: EFORT Open Rev 2021;6:618-628. DOI: 10.1302/2058-5241.6.200116.

Comparable outcomes of recycled autografts and allografts for reconstructions in patients with high-grade osteosarcoma.

PURPOSE: This retrospective, single-centre study compares the clinical and radiographic outcomes of limb reconstruction using recycled autografts to that using allografts. METHODS: Patients with histopathologically verified high-grade osteosarcoma treated with wide bone resection and limb reconstruction using allografts or recycled autografts from January 1998 through December 2012 were retrospectively screened for enrolment eligibility. The final study cohort included 255 patients (allograft, 91; recycled autograft, 164). Data regarding post-operative complications, salvage treatment, and graft survival were collected. A modified International Society of Limb Salvage classification system was used to evaluate the radiographic findings. RESULTS: The time to graft-host union did not differ significantly between the two graft types. Patients receiving recycled autografts had fewer complications compared than did those receiving allografts (recycled autografts vs. allograft: structural failure, 4.3 vs. 13.2%; late infection, 2.4 vs. 7.7%; all p < 0.05). Complications occurred most frequently during the first three years after surgery, and the majority were manageable. The five year limb survival rate did not differ significantly between the two graft types (91.3 vs. 94.0%; p = 0.752). No local oncological recurrence was observed within the recycled autografts. CONCLUSION: Recycled autografts and allografts are feasible options for biological limb reconstructions in terms of complications and graft survival after wide resection of osteosarcoma.

Significantly reducing blood loss via a peri-articular injection of tranexamic acid during total knee arthroplasty: a retrospective study.

BACKGROUND: The administration of an intra-articular injection (IAI) of tranexamic acid (TXA) has been demonstrated to be effective in reducing both blood loss and transfusion rate during total knee arthroplasty (TKA); however, few studies have reported the efficiency of a peri-articular injection (PAI) of TXA. We studied the efficiency of a PAI of TXA in reducing blood loss during TKA. METHODS: Fifty patients undergoing primary simultaneous bilateral TKA were enrolled in this retrospective study. The right knee received a PAI of 1 g of TXA (Group I), and the left knee received an IAI of 1 g of TXA (Group II). The clinical outcome measures were a change in blood loss from Hemovac drains and surgical time. RESULTS: The decrease in blood loss from the Hemovac was significantly lower in Group I (460.1 ± 36.79 vs. 576.0 ± 34.01, P < 0.001) than in Group II, and no significant difference in surgical times was observed. The blood transfusion rate in the present study was 16 %. CONCLUSIONS: A PAI of TXA may reduce blood loss more efficiently than an IAI of TXA during TKA without increased complications such as surgical site infection, poor wound healing, skin necrosis, pulmonary embolism, and deep vein thrombosis.

Characterization of Osteogenesis and Chondrogenesis of Human Decellularized Allogeneic Bone with Mesenchymal Stem Cells Derived from Bone Marrow, Adipose Tissue, and Wharton's Jelly.

Allogeneic bone grafts are a promising material for bone implantation due to reduced operative trauma, reduced blood loss, and no donor-site morbidity. Although human decellularized allogeneic bone (hDCB) can be used to fill bone defects, the research of revitalizing hDCB blocks with human mesenchymal stem cells (hMSCs) for osteochondral regeneration is missing. The hMSCs derived from bone marrow, adipose tissue, and Wharton's jelly (BMMSCs, ADMSCs, and UMSCs, respectively) are potential candidates for bone regeneration. This study characterized the potential of hDCB as a scaffold for osteogenesis and chondrogenesis of BMMSCs, ADMSCs, and UMSCs. The pore sizes and mechanical strength of hDCB were characterized. Cell survival and adhesion of hMSCs were investigated using MTT assay and F-actin staining. Alizarin Red S and Safranin O staining were conducted to demonstrate calcium deposition and proteoglycan production of hMSCs after osteogenic and chondrogenic differentiation, respectively. A RT-qPCR was performed to analyze the expression levels of osteogenic and chondrogenic markers in hMSCs. Results indicated that BMMSCs and ADMSCs exhibited higher osteogenic potential than UMSCs. Furthermore, ADMSCs and UMSCs had higher chondrogenic potential than BMMSCs. This study demonstrated that chondrogenic ADMSCs- or UMSCs-seeded hDCB might be potential osteochondral constructs for osteochondral regeneration.

Risk factors and modes of failure in the modern dual mobility implant. A systematic review and meta-analysis.

BACKGROUND: The aims of this meta-analysis were to: (1) validate the outcome of modern dual mobility (DM) designs in patients who had undergone primary and revision total hip arthroplasty (THA) procedures and (2) to identify factors that affect the outcome. METHODS: We searched for studies that assessed the outcome of modern DM-THA in primary and revision procedures that were conducted between January, 2000 to August, 2020 on PubMed, MEDLINE, Cochrane Reviews and Embase. The pooled incidence of the most common failure modes and patient reported outcomes were evaluated in patients who have received: (1) primary THA, (2) revision THA for all causes or (3) for recurrent dislocation. A meta-regression analysis was performed for each parameter to determine the association with the outcome. The study design of each study was assessed for potential bias and flaws by using the quality assessment tool for case series studies. RESULTS: A total of 119 studies (N= 30016 DM-THAs) were included for analysis. The mean follow-up duration was 47.3 months. The overall implant failure rate was 4.2% (primary: 2.3%, revision for all causes: 5.5%, recurrent dislocation: 6.0%). The most common failure modes were aseptic loosening (primary: 0.9%, revision for all causes: 2.2%, recurrent dislocation: 2.4%), septic loosening (primary:0.8%, revision for all causes: 2.3%, recurrent dislocation: 2.5%), extra-articular dislocation (primary:0.6%, revision for all causes:1.3%, recurrent dislocation:2.5%), intra-prosthetic dislocation (primary:0.8%, revision for all causes:1.0%, recurrent dislocation:1.6%) and periprosthetic fracture (primary:0.9%, revision for all causes:0.9%, recurrent dislocation:1.3%). The multi-regression analysis identified younger age (ß=-0.04, 95% CI -0.07 - -0.02) and female patients (ß=3.34, 95% CI 0.91-5.78) were correlated with higher implant failure rate. Age, gender, posterolateral approach and body mass index (BMI) were not risk factors for extra-articular or intra-prosthetic dislocation in this cohort. The overall Harris hip score and Merle d'Aubigné score were 84.87 and 16.36, respectively. Level of evidence of this meta-analysis was IV. CONCLUSION: Modern dual-mobility designs provide satisfactory mid-term implant survival and clinical performance. Younger age and female patients might impact the outcome after DM-THA. Future research directions should focus on, (1) long-term outcome of modern dual-mobility design, including specific concerns such as intra-prosthetic dislocation and elevated metal ion, and (2) cost-effectiveness analysis of dual-mobility implant as an alternative to conventional THA for patients who are at high risk of dislocation.

An opioid-sparing protocol with intravenous parecoxib can effectively reduce morphine consumption after simultaneous bilateral total knee arthroplasty.

Multimodal pain management protocol effectively relieves pain following simultaneous bilateral total knee arthroplasty (SBTKA) but is associated with administration of large amounts of opioids in the perioperative period. In this prospective, randomized, assessor-blinded, single-surgeon clinical trial, the goal was to validate the efficacy of an opioid-sparing protocol for SBTKA with a reduced opioid dose, while achieving similar pain relief with few adverse events. Fifty-six patients who had undergone SBTKA were randomly allocated to receive either an opioid-sparing or opioid-based protocol. The primary outcome parameters were visual analogue scale (VAS) scores at rest, with movement, and cumulative morphine dose, through time. Secondary outcome parameters included drug-related adverse events and range of motion with continuous passive motion device, through time. In the opioid-sparing group, a lower VAS score with movement at postoperative 24 and 72 h was observed compared with the opioid-based group, but the difference did not reach the minimal clinically importance difference. A reduced cumulative morphine dose was noted in the opioid-sparing group at postoperative 24, 48 and 72 h. In conclusion, the opioid-sparing protocol may be used as an alternative modality for pain management following SBTKA. Similar pain relief effects may be achieved utilizing a reduced cumulative opioid dose, with few opioid related adverse events.

Uncemented femoral stem design might have an impact on postoperative periprosthetic femur fracture pattern. A Comparison between flat-wedge and dual-wedge stems.

INTRODUCTION: Type I, flat-wedge and type II, dual-wedge stems are currently two common stem types used in primary, uncemented hip arthroplasty. The prevalence of periprosthetic femur fracture is higher in type I stems, possibly because of the different shapes and areas of bone contact. We aimed to compare the fracture pattern, stem stability during the fracture and type of subsequent procedures in periprosthetic femur fractures between type I and II stems. MATERIALS AND METHODS: This was a retrospective, cross-sectional study conducted in a single tertiary referral hospital of Taipei, Taiwan. We included primary hip arthroplasty procedures using type I or type II stems complicated with postoperative periprosthetic femur fractures. We recorded the age, sex, ASA grade, index procedure, institution of where the index procedure was performed, trauma mechanism, time from index procedure to fracture, procedure for periprosthetic fracture and radiographic parameters including Dorr type, Vancouver classification, stem stability, fracture pattern, type and brand of the stems for analysis. RESULTS: We included 132 patients who had undergone surgery for periprosthetic femur fracture for type I (N = 46) or type II (N = 86) stems. The mean age was 74.5 years and 52.3% of the patients were female. Type I stems were associated with a higher proportion of a complex fracture pattern (52.2% vs. 8.2%), femoral stem loosening (78.2% vs. 60.4%) and a higher rate of revision stem procedures (69.6% vs. 50.0%) compared with type II stems. Using multivariate analysis, type I stem was the only factor for a complex fracture pattern in the overall population (aOR: 23.60, 95% CI: 6.54-85.16), hemiarthroplasty (aOR: 160.50, 95% CI: 9.77-2635.95) and total hip arthroplasty (aOR: 14.17, 95% CI: 2.92-68.79) subgroups. CONCLUSION: We observed a difference in fracture patterns between type I and type II stems. Type I stems appear to be an independent risk factor for a complex fracture pattern in patients who had undergone primary hip arthroplasty.