Age-adjusted Charlson Comorbidity Index as an effective tool for the choice between simultaneous or staged bilateral total knee arthroplasty.

INTRODUCTION: The choice between simultaneous and staged bilateral total knee arthroplasty (BTKA) remains controversial. Age-adjusted Charlson Comorbidity Index(CCI) is a promising tool for risk-stratification. We aimed to compare the outcomes between patients who underwent simultaneous and staged BTKA, stratified by age-adjusted CCI scores. MATERIALS AND METHODS: We conducted this retrospective, single-surgeon case series from 2010 to 2020. This study consisted of 1558 simultaneous BTKA and 786 staged BTKA procedures. The outcome domains included 30-day and 90-day readmission and 1-year reoperation events. We performed multivariate regression analysis to compare the risk of readmission and reoperation following simultaneous and staged BTKA. Other factors included age, sex, body mass index, diabetes mellitus, rheumatoid arthritis, smoking, receiving thromboprophylaxis and blood transfusion. RESULTS: The rates of 30-day, 90-day readmission and 1-year reoperation following simultaneous BTKA was 1.99%, 2.70% and 0.71%, respectively. The rates of 30-day, 90-day readmission and 1-year reoperation following staged BTKA was 0.89%, 1.78% and 0.89%, respectively. For patients with age-adjusted CCI ≥ 4 points, simultaneous BTKA was associated with a higher risk of 30-day (aOR:3.369, 95% CI:0.990-11.466) and 90-day readmission (aOR:2.310, 95% CI:0.942-5.668). In patients with age-adjusted CCI ≤ 3 points, the risk of readmission and reoperation was not different between simultaneous or staged BTKA. CONCLUSION: Simultaneous BTKA was associated with an increased risk of short-term readmissions in patients with age-adjusted CCI ≥ 4 points but not in those with age-adjusted CCI ≤ 3 points. Age-adjusted CCI can be an effective index for the choice between simultaneous and staged BTKA procedures.

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.

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.

Analyzing BMP2, FGFR, and TGF Beta Expressions in High-Grade Osteosarcoma Untreated and Treated Autografts Using Proteomic Analysis.

In the last few decades, biological reconstruction techniques have improved greatly for treating high-grade osteosarcoma patients. To conserve the limb, and its function the affected tumor-bearing bones have been treated using liquid nitrogen and irradiation processes that enable the removal of entire tumors from the bone, and these treated autografts can be reconstructed for the patients. Here, we focus on the expressions of the growth factor family proteins from the untreated and treated autografts that play a crucial role in bone union, remodeling, and regeneration. In this proteomic study, we identify several important cytoskeletal, transcriptional, and growth factor family proteins that showed substantially low levels in untreated autografts. Interestingly, these protein expressions were elevated after treating the tumor-bearing bones using liquid nitrogen and irradiation. Therefore, from our preliminary findings, we chose to determine the expressions of BMP2, TGF-Beta, and FGFR proteins by the target proteomics approach. Using a newly recruited validation set, we successfully validate the expressions of the selected proteins. Furthermore, the increased growth factor protein expression after treatment with liquid nitrogen may contribute to bone regeneration healing, assist in faster recovery, and reduce local recurrence and metastatic spread in high-grade sarcoma patients.

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.

Cementation of the highly cross-linked polyethylene liner into a well-fixed acetabular shell to treat patients with recurrent dislocation after total hip arthroplasty.

Cementation of a highly cross-linked polyethylene liner into a well-fixed acetabular shell provided a good durability for liner wear. However, its efficacy in treating recurrent instability due to malposition cup is less reported. The aim of this study is to evaluate the outcome of this surgical technique to treat hip instability. From 2009 to 2019, we have identified 38 patients who had been surgically treated for recurrent instability, including cementation liner (N = 20) and revision cup (N = 18) procedures. Patients were followed for a mean of 45.66 months. We have recorded and analyzed all causes of implant failure including recurrent instability. Clinical outcomes were assessed including complication and Harris Hip Score (HHS) preoperatively and at the latest follow-up. Revision-free survivorship for any cause was 95.0% at 1 year, and 84.4% at 5 years in cementation liner group and 88.9% at 1 year and 5 years in revision cup group. Mean Harris hip score improved from 48.3 points preoperatively to 79.5 points at the last follow-up in cementation liner group and mean HHS improved from 43.3 points preoperatively to 77.2 points in revision cup group. There were two implant failures in each group, including one is due to persistent hip instability and the other is due to periprosthetic joint infection in the cementation liner group and two implant failure are due to persistent hip instability in the revision cup group. Functional scores and implant survival were similar in both groups. We demonstrated that orientation correction via the cementation of the polyethylene liner into well-fixed acetabular shell is a promising option to treat and prevent instability. Level of Evidence: Therapeutic Level IV.

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.

Comparison of recycled autograft versus allograft in osteosarcoma with pathological fracture.

PURPOSE: The recycled autograft in biological reconstruction for osteosarcoma has satisfactory outcome. There are few studies about its efficacy in pathological fracture. The aim of the study is to compare the clinical results of recycled autograft to those of allograft in patients with high-grade osteosarcoma with pathological fracture. PATIENTS AND METHODS: Between October 2010 and March 2018, 30 patients with osteosarcoma combining pathological fracture underwent biological reconstruction. Eleven patients received recycled autograft via extracorporeal irradiation or freezing nitrogen and nineteen patients restored bone defect via allograft to accomplish biological reconstruction. RESULTS: The mean follow-up was 58.1 months (range 12-120). The mean time to graft-host union of limbs reconstructed using recycled autografts and allografts was 17.45 ± 13.54 and 12.63 ± 12.62 months, respectively, with no significant difference observed between groups (p = 0.176). The five year probability of graft failure therefore did not significantly differ between groups (p = 0.245). The patient five year survival rate was similar (p = 0.229). Post-operative complication rates were similar for the recycled autograft group (54.5%) and the allograft group (57.9%). CONCLUSION: The recycled autograft showed comparable clinical results, graft-host union time, complication rate, and graft survival to allograft in biological reconstruction for osteosarcoma with pathological fracture.

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.

Suppression of Estrogen Receptor Alpha Inhibits Cell Proliferation, Differentiation and Enhances the Chemosensitivity of P53-Positive U2OS Osteosarcoma Cell.

Osteosarcoma is a highly malignant musculoskeletal tumor that is commonly noticed in adolescent children, young children, and elderly adults. Due to advances in surgery, chemotherapy and imaging technology, survival rates have improved to 70-80%, but chemical treatments do not enhance patient survival; in addition, the survival rate after chemical treatments is still low. The most obvious clinical feature of osteosarcoma is new bone formation, which is called "sun burst". Estrogen receptor alpha (ERα) is an essential feature of osteogenesis and regulates cell growth in various tumors, including osteosarcoma. In this study, we sought to investigate the role of ERα in osteosarcoma and to determine if ERα can be used as a target to facilitate the chemosensitivity of osteosarcoma to current treatments. The growth rate of each cell clone was assayed by MTT and trypan blue cell counting, and cell cycle analysis was conducted by flow cytometry. Osteogenic differentiation was induced by osteogenic induction medium and quantified by ARS staining. The effects of ERα on the chemoresponse of OS cells treated with doxorubicin were evaluated by colony formation assay. Mechanistic studies were conducted by examining the levels of proteins by Western blot. The role of ERα on OS prognosis was investigated by an immunohistochemical analysis of OS tissue array. The results showed an impaired growth rate and a decreased osteogenesis ability in the ERα-silenced P53(+) OS cell line U2OS, but not in P53(-) SAOS2 cells, compared with the parental cell line. Cotreatment with tamoxifen, an estrogen receptor inhibitor, increased the sensitivity to doxorubicin, which decreased the colony formation of P53(+) U2OS cells. Cell cycle arrest in the S phase was observed in P53(+) U2OS cells cotreated with low doses of doxorubicin and tamoxifen, while increased levels of apoptosis factors indicated cell death. Moreover, patients with ER-/P53(+) U2OS showed better chemoresponse rates (necrosis rate > 90%) and impaired tumor sizes, which were compatible with the findings of basic research. Taken together, ERα may be a potential target of the current treatments for osteosarcoma that can control tumor growth and improve chemosensitivity. In addition, the expression of ERα in osteosarcoma can be a prognostic factor to predict the response to chemotherapy.

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.

Adjuvant therapy by high-speed burr may cause intraoperative bone tumor seeding: an animal study.

BACKGROUND: Bone tumors are often treated with intralesional curettage. High-speed burring, an adjuvant therapy, was performed to maximize the tumor cell killing; however, tumor recurrence might still occur, which may be caused by residual tumor or local tumor spread during surgery. METHODS: A porcine cadaver (femur) was utilized to determine whether the use of a high-speed burr causes bone cement spray. To mimic residual tumor after curettage, luminescent cement was smeared on two locations of the bone cavity, the wall and the bottom. The cavity in the femoral bone was then placed in the middle of a sheet of drawing paper featuring 10 cm, 20 cm, and 30 cm concentric circles. The luminescent cement was then burred totally with a high-speed burr. RESULTS: The intensity of the area in the wall in circle I was 72.6% ± 5.8%; within circle II, it was 22.1% ± 4.2%; and within circle III, it was 5.4% ± 1.5%. The intensity of the area within the bottom of the femoral bone within circle I was 66.5% ± 6.1%, within circle II was 28.1 ± 4.8%, and within circle III, it was 5.4% ± 1.4%. The amount of luminescent cement seeding decreased with distance, but there was no difference while burring at different locations of the bone cavity. Under the handpiece cover, a greater amount of cement spray was retained in circle I during burring of the cement in the bottom of the cavity and less was sprayed out in circle III. CONCLUSIONS: High-speed burring may cause explosive bone cement spray, which could extend to 20 cm. The intensities of spray did not decrease, even when the handpiece cover was used. The wide range of bone cement spray caused by high-speed burr was inspected in this pilot study, which may lead to tumor seeding. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Low rates of all-cause revision in displaced subcapital femoral neck fractures treated with hip hemiarthroplasty - a retrospective review of 4516 patients from a single institute.

BACKGROUND: Femoral neck fracture (FNF) is among the commonest fractures affecting the geriatric population. Hemiarthroplasty (HA) is a standard treatment procedure and has been performed by hip surgeons for decades. Recently, primary total hip replacement has proved advantageous for the treatment of such fractures. The aim of this study is to retrospectively review all causes of failure of all patients who underwent HA in our institute and reevaluated whether HA remains a favourable choice of treatment for patients with displaced FNFs. METHODS: A total of 4516 patients underwent HA at our centre from 1998 to 2017. The HA implants included unipolar and bipolar prostheses. Patients diagnosed with displaced FNF, underwent primary HA initially, required second revision procedures, and followed up for a minimum of 36 months were included in this study. Data were collected and comprehensively analysed. RESULTS: In 4516 cases, 99 patients underwent second surgeries. The revision rate was 2.19%. Reasons for failure were acetabular wear (n = 30, 30.3%), femoral stem subsidence (n = 24, 24.2%), periprosthetic fracture (n = 22, 22.2%), infection (n = 16, 16.2%), and recurrent dislocation (n = 7, 7.1%). The mean follow-up period was 78.1 months. The interval between failed HA and revision surgery was 22.8 months. CONCLUSION: HA has a low revision rate and remains a favourable choice of treatment for patients with displaced FNFs. LEVELS OF EVIDENCE: Level III, Retrospective Cohort Study, Therapeutic Study.

The efficacy of continuous versus single-injection femoral nerve block in Total knee Arthroplasty: a systematic review and meta-analysis.

BACKGROUND: Continuous femoral nerve block (cFNB) has been developed to extend the analgesic effect since the efficacy of single-injection femoral nerve block (sFNB) is often limited to approximately 16-24 h. The aim of this meta-analysis was to validate the add-on effect of cFNB in the setting of a multimodal analgesic protocol. METHODS: We performed a comprehensive literature review on Web of Science, Embase, the Cochrane Library and PubMed. Eight randomized controlled trials (N = 626) that compared the efficacy of cFNB with sFNB were included. The primary outcome domains consist of visual analog scale (VAS) score at postoperative 24 and 48 h. The secondary outcome domains include opioid consumption, length of hospital stay and incidence of nausea. RESULTS: Our analysis revealed that cFNB was associated with a lower VAS score at 24 h (SMD: -0.277;95% CI - 0.503 to - 0.05). However, the difference of VAS score did not meet the minimal clinically importance difference for total knee arthroplasty (TKA). VAS score at 48 h was similar between the cFNB and sFNB group. The cFNB group was associated with less amount of opioids consumed at both 24(SMD: -1.056;95% CI - 1.737 to - 0.375) and 48 h(SMD: -1.040;95% CI - 1.790 to - 0.289). Length of hospital stay and incidence of nausea were similar between the two groups. CONCLUSION: In the setting of a multimodal analgesic protocol, patients might benefit from cFNB with regards to a reduced need of opioids in the early postoperative period. However, we did not find a clinically significant difference in pain scores at different time points between the cFNB and sFNB group. LEVEL OF EVIDENCE: I; meta-analysis.

Is short-course systemic antibiotic therapy using an antibiotic-loaded cement spacer safe after resection for infected total knee arthroplasty? A comparative study.

BACKGROUD/PURPOSE: Most patients who undergo two-stage exchange arthroplasty surgery for total knee arthroplasty prosthetic joint infection (TKA-PJI) receive a six-week course of systemic antibiotic treatment after the first stage procedure. However, the optimal duration of therapy has not been conclusively determined. METHODS: We included 64 patients with periprosthetic knee infection who had undergone two-stage exchange arthroplasty. Between March 2003 and December 2009, 21 patients were given a short-course (less than 1 week) antibiotic treatment, and 43 were given a standard-course (4-6 weeks) treatment during the interim period. We compared length of hospital stay, duration of intravenous and overall systemic antibiotic treatments, and rate of recurrent periprosthetic knee infection between groups. RESULTS: Short-course antibiotic treatment was associated with a shorter hospital stay and a shorter duration of intravenous and systemic antibiotic treatment. Implant survival regarding re-resection arthroplasty and chronic oral antibiotic suppression as primary endpoints was not significant different statistically between two groups (p = 0.317). The 1-year implant survival rates were 91.7% in the short-course group and 89.8% in the standard-course group. The 5-year implant survival rates were 85.2% and 74.0%, respectively. CONCLUSION: After the first stage of resection arthroplasty for a two-stage exchange arthroplasty, a short course of antibiotic treatment had similar implant survival rates in comparison to the standard 6-week course. With radical debridement combined with an antibiotic-loaded cement spacer along with serial monitoring of the patient, a short course antibiotic treatment may be adequate in patients with TKA-PJI.

Exploring the Proteomic Alterations from Untreated and Cryoablation and Irradiation Treated Giant Cell Tumors of Bone Using Liquid-Chromatography Tandem Mass Spectrometry.

Giant cell tumors of bone (GCT) are benign tumors that show a locally aggressive nature and affect bones' architecture. Recently, cryoablation and irradiation treatments have shown promising results in GCT patients with faster recovery and less recurrence and metastasis. Therefore, it became a gold standard surgical treatment for patients. Hence, we have compared GCT-untreated, cryoablation, and irradiation-treated samples to identify protein alterations using high-frequency liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Our label-free quantification analysis revealed a total of 107 proteins (p < 0.01) with 26 up-regulated (< 2-folds to 5-fold), and 81 down-regulated (> 0.1 to 0.5 folds) proteins were identified from GCT-untreated and treated groups. Based on pathway analysis, most of the identified up-regulated proteins involved in critical metabolic functions associated with tumor proliferation, angiogenesis, and metastasis. On the other hand, the down-regulated proteins involved in glycolysis, tumor microenvironment, and apoptosis. The observed higher expressions of matrix metalloproteinase 9 (MMP9) and TGF-beta in the GCT-untreated group associated with bones' osteolytic process. Interestingly, both the proteins showed reduced expressions after cryoablation treatment, and contrast expressions identified in the irradiation treated group. Therefore, these expressions were confirmed by immunoblot analysis. In addition to these, several glycolytic enzymes, immune markers, extracellular matrix (ECM), and heat shock proteins showed adverse expressions in the GCT-untreated group were identified with favorable regulations after treatment. Therefore, the identified expression profiles will provide a better picture of treatment efficacy and effect on the molecular environment of GCT.

Bone morphogenetic protein activity preservation with extracorporeal irradiation- and liquid nitrogen freezing-treated recycled autografts for biological reconstruction in malignant bone tumor.

Recycled autografts have been commonly used in biological reconstruction in conjunction with wide bone resection. Extracorporeal irradiation (ECIR) and freezing are the two major options for pretreating tumor-bearing autografts before transplant. This study, for the first time, compared the effects of these two techniques on bone morphogenetic protein (BMP)-2 activity. Bone tissue extracted from human femoral heads were treated through either ECIR at different doses (5000, 15,000, and 30,000 rad) or liquid nitrogen (LN) freezing for different durations (5, 10, and 15 min). The amount of BMP was analyzed through enzyme-linked immunosorbent assay (ELISA assay). Furthermore, we also used tandem mass spectrometry to analyze change of BMP-2 and BMP-7 expression after high dosage of irradiation (30,000 rad) and long-time of freezing (15 min). To directly evaluate the effect of ECIR or LN freezing treatment on the activity of BMP, commercial recombinant human BMP-2 (rhBMP-2) was added to the culture of human mesenchymal stem cells (hMSCs). The post-treatment activity of rhBMP-2 was quantitated by measuring the osteogenic differentiation of hMSCs with Alizarin Red S staining. Through Western blotting, the activation of the BMP signaling pathway by phospho-Smad antibodies was analyzed. Our results showed that post-treatment levels of BMP did not differ among the ECIR and LN freezing treatments in ELISA assay, but tandem mass spectrometry showed significantly lower expression of BMP-2 after 30,000 rad of irradiation. Both ECIR and freezing lowered the expression of regulatory factors involved in the BMP-activated signaling cascades and similar results were also observed in osteogenic differentiation of hMSCs. However, LN freezing preserved better bioactivity of rhBMP-2 whereas dosage-dependent declination was observed in ECIR groups. In conclusion, considering BMP-2 activity, LN freezing-treated autografts may result in a better osteoinduction outcomes than those treated using ECIR. Further investigation of the factors involved in bone formation is required.

The efficacy and safety of continuous versus single-injection popliteal sciatic nerve block in outpatient foot and ankle surgery: a systematic review and meta-analysis.

BACKGROUND: Continuous popliteal sciatic nerve block (CPSNB) has been performed in outpatient foot and ankle surgery as a regional anesthesia method to relieve postoperative pain. Its efficacy as well as safety is yet to be established. There are two purposes of this study: (1) to validate the efficacy of CPSNB with regards to better pain relief and reduced analgesics consumption; (2) to assess the safety of CPSNB. METHODS: We performed a comprehensive literature review on Web of Science, the Cochrane Library, PubMed and Embase and only included randomized controlled trials (RCTs). Five RCTs that compared the efficacy and safety of CPSNB with the single-injection popliteal sciatic nerve block group were included. The primary outcome parameters were visual analog scale (VAS) scores at postoperative 24, 48 and 72 h. The secondary outcome parameters were amount of oral analgesics consumed, overall patient satisfaction and need of admission after surgery. A sensitivity analysis was performed to explore the consistency of the results. RESULTS: In comparison with the single-injection group, CPSNB was associated with a lower VAS score at postoperative 24 and 48 h (p < 0.05). There were no neuropathic symptoms or infection events after the nerve block. However, there were several minor complications associated with the pump and catheter system, with drug leakage being the most common complication (N = 26 of 187, 13.9%). CONCLUSION: CPSNB is an effective method in pain management for outpatient foot and ankle surgery. Both methods appear to be safe as none of the patients experienced neuropathic symptoms or infection. Further studies with larger sample size are needed to compare the risk of major complications between the two methods. LEVEL OF EVIDENCE: I; meta-analysis.

The efficacy of intraoperative periarticular injection in Total hip arthroplasty: a systematic review and meta-analysis.

BACKGROUND: Periarticular injection (PAI) is a regional analgesia method performed in total hip arthroplasty (THA) for postoperative pain relief. However, its efficacy and safety is still inconclusive. Therefore, we conducted this meta-analysis to assess the safety of PAI and to determine if PAI provides better pain relief and reduce the consumption of opioids after THA. METHODS: We searched PubMed, Web of Science, Embase and the Cochrane Library comprehensively. Only randomized control trials were included in our meta-analysis. Eleven studies that compared the efficacy of PAI with the control group were included. The preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines and Jadad score were applied to assess the quality of the included studies. We used the recommendations by the Cochrane Collaboration to reduce bias and to ensure our results were reliable and veritable. RESULTS: Our analysis demonstrated that PAI was more effective than the control group with a lower visual analog scale (VAS) score during rest at 24 h (P = 0.003), 48 h (P = 0.002), and VAS score with activity at 24 h (P = 0.04). There was also less amount of opioid consumption (P = 0.01). There were no differences in length of hospital stay (P = 0.526) and postoperative nausea rate (P = 0.153). CONCLUSION: Compared with the control group, PAI showed better pain relief and less amount of opioid consumption after THA. Our meta-analysis suggests that PAI is a safe and effective multimodal analgesia technique that can be used for THA.

A safety comparative study between freezing nitrogen ethanol composite and liquid nitrogen for cryotherapy of musculoskeletal tumors.

Freezing nitrogen ethanol composite (FNEC) showed effective cryoablative ability for bone tumor ex vivo and in vivo comparable to liquid nitrogen (LN). We therefore wished to compare the radiant cooling damage of the surrounding tissue between FNEC and LN. The evaluation of the radiant cooling damage was demonstrated human bone xenograft transplantation (HXT) in a mouse model. Characterizations and quantifications of the damaging effects on morphologic features and apoptosis of the cryoablative surrounding bone tissue, muscle and epidermal layer of skin were compared. The radiant cooled damaging effects including epidermal rupture, hair follicle atrophy, dermis and subcutaneous crystal vacuolation of skin were significantly greater in LN than FNEC. Muscular apoptosis, structural shrinkage and bone cellular apoptosis were supposedly 15%-33% destroying degrees of LN more than FNEC. We concluded that FNEC is an innovative cryogenic material, and it could cause less cryoablative damage to surrounding normal tissue than LN. The findings might support the safety of FNEC being applied in clinical cryoablation therapy.