Groin pain aggravated in short term contracted by COVID-19 in THA patients: a case-crossover study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) rapidly spreads worldwide and causes more suffering. The relation about the aggravation of inguinal pain and COVID-19 was unclear in patients with total hip arthroplasty (THA). This study aimed to evaluate the risk of groin pain aggravation in short-term THA patients after COVID-19. METHODS: Between 2020 and 2022, 129 patients with THA who were affected COVID-19 were enrolled. A short-standardized questionnaire was administered during follow-up to inquire about the aggravation of groin ache before and after SARS-COV-2 affection. Furthermore, we evaluated the potential association between the presence of increased pain and various factors, including age, gender, body mass index, diagnosis, and length of hospital stay. RESULTS: The case-crossover study revealed an increased risk of inguinal soreness aggravation when comparing 8 weeks after COVID-19 with 12 weeks before COVID-19 (Relative risk [RR], 9.5; 95% Confidence intervals [CI], 2.259-39.954). For COVID-19 positive patients, multivariate analysis showed length of stay was an independent factor significantly associated with increased risk of aggravation of groin pain (Odds ratio [OR], 1.26; 95%CI, 1.03-1.55, p = 0.027). CONCLUSION: This study confirms the association between COVID-19 and the exacerbation of soreness in the groin region in THA patients and extended length of stay is a possible contributing factor. This study expands the current literature by investigating the risk of aggravation of inguinal pain in patients with THA after COVID-19, providing valuable insights into postoperative outcomes in this specific population. Trial registration This retrospective study was approved by the Institutional Review Board of Shanghai general hospital (No.2023-264).

Radiographic study of direct anterior approach hip arthroplasty: a 10-15 year follow-up of Chinese patients.

BACKGROUND: Controversy remains over whether different surgical approaches exert an impact on the component positioning in total hip arthroplasty. We conducted a retrospective study to reveal the long-term position of prostheses in the first group of patients in China who underwent direct anterior hip arthroplasty. METHODS: Collected were data from 350 patients who underwent direct anterior hip arthroplasty between 2008 and 2013, including demographic information, imaging data, Harris hip scores, and surgical complications. Variables, measured radiographically or by CT, included hip offset, leg length discrepancy, component position, and stability within one week after surgery and at the last follow-up. The data were subjected to statistical analysis by using paired t-tests and Pearson chi-square tests. RESULTS: Data were harvested by follow-up and self-reported questionnaires. The postoperative follow-up lasted for 13.1 years on average (minimum, 10 years; maximum, 15 years), and the overall survival rate of hip prostheses was 96.3%. The mean Harris score at the final follow-up was 91.8 points. After excluding patients with significant preoperative hip deformities, the incidence of postoperative limb inequality (> 5 mm) was 4.9% at the last follow-up, and the incidence of hip offset discrepancy (> 5 mm) was 14.6%. The overall proportion of the acetabular components located in the Lewinnek safe zone was 77.7%, whereas the proportion of femoral prostheses in the safe zone (< 3° inclination) was 94.0%. Based on the revised data and the last follow-up imaging, the total proportion of acetabular and femoral prostheses with a radiolucence of > 2 mm was 5.1%. CONCLUSION: Direct anterior approach hip arthroplasty could achieve excellent component positioning and long-term prosthesis survival in patients without severe hip deformities.

Angiopoietin 1 Relieves Osteolysis by Promoting Macrophage Mitophagy Through the TBK1-SQSTM1 Pathway to Inhibit AIM2 Inflammasome-Mediated Pyroptosis.

Osteolysis resulting from wear particles and subsequent aseptic loosening is a leading cause of revision surgery of artificial joints. The underlying pathogenesis of particle-induced osteolysis (PPO) has remained largely uncertain. Addressing how to mitigate osteolysis caused by wear particles presents a significant challenge for orthopedic surgeons. This study aimed to explore the molecular mechanism by which Angiopoietin (Ang-1) inhibits osteoclast activation to alleviate osteolysis. RAW264.7 mouse macrophages were stimulated with LPS or RANKL to induce osteoclast formation. Additionally, titanium (Ti) particles (50 mg) were subperiosteally implanted around the cranial suture of mice to establish a calvarial osteolysis model. Ang-1, a member of the pro-angiogenic factor protein family and an important inflammatory regulator molecule, was utilized in this model. TRAP staining was utilized to detect osteoclast activation, while a western blot was conducted to identify key proteins associated with mitophagy and pyroptosis. Scanning electron microscopy was employed to observe the morphology and dimensions of Ti particles. Additionally, a combination of micro-CT, H&E, Masson's trichrome, and immunohistochemical staining techniques were applied to analyze the calvarial samples. Results indicated that Ang-1 could inhibit LPS- or RANKL-induced osteoclastogenesis and alleviate Ti particle-induced calvarial osteolysis in mice. TBK-1, a key signaling molecule involved in initiating mitophagy, was found to be mechanistically enhanced by Ang-1 through promoting TBK-1 phosphorylation in macrophages. This process inhibited AIM2 inflammasome-mediated pyroptosis and impeded osteoclastogenesis. Overall, this research uncovers a novel mechanism by which Ang-1 can attenuate inflammatory osteolysis, potentially offering a new therapeutic approach for PPO.

BRG1 mediates protective ability of spermidine to ameliorate osteoarthritic cartilage by Nrf2/KEAP1 and STAT3 signaling pathway.

BACKGROUND: Spermidine (SPD) is a natural polyamine that shows beneficial effects on osteoarthritis (OA). However, the effect of SPD on cartilage inflammation remains unknown. This study aimed to investigate the potential mechanisms underlying the protective effect of SPD against OA-induced articular cartilage degradation. METHOD: SW1353 human chondrocytes were treated with hydrogen peroxide and lipopolysaccharide to induce models of inflammation and oxidative stress, followed by different dose of SPD intervention. Moreover, mice that underwent anterior cruciate ligament transection were bred and treated with SPD. The effects of SPD were observed using a CCK-8 kit, real-time polymerase chain reaction, immunoblotting, and immunofluorescent assays. RESULT: SPD significantly increased the expression of antioxidant proteins, chondrogenic genes, and inflammatory factors both in vivo and in vitro. And injury of the mouse cartilage was also reduced by SPD. Moreover, SPD activated the Nrf2/KEAP1 pathway and inhibited STAT3 phosphorylation. BRG1 expression was decreased in osteoarthritic mouse cartilage, whereas SPD treatment caused an upregulation. However, when BRG1 was specifically inhibited by an adeno-associated virus and small interfering RNA, the antioxidant and anti-inflammatory effects of SPD were significantly diminished both in vitro and in vivo. CONCLUSION: We found that SPD ameliorated cartilage damage in OA by activating the BRG1-mediated Nrf2/KEAP1 pathway. SPD and BRG1 may provide new therapeutic options or targets for the treatment of OA.

Pyroptosis in Periprosthetic Osteolysis.

Periprosthetic osteolysis (PPO) along with aseptic loosening (AL) caused by wear particles after artificial joint replacement is the key factor in surgical failure and subsequent revision surgery, however, the precise molecular mechanism underlying PPO remains unclear. Aseptic inflammation triggered by metal particles, resulting in the imbalance between bone formation by osteoblasts and bone resorption by osteoclasts may be the decisive factor. Pyroptosis is a new pro-inflammatory pattern of regulated cell death (RCD), mainly mediated by gasdermins (GSDMs) family, among which GSDMD is the best characterized. Recent evidence indicates that activation of NLRP3 inflammasomes and pyroptosis play a pivotal role in the pathological process of PPO. Here, we review the pathological process of PPO, the molecular mechanism of pyroptosis and the interventions to inhibit the inflammation and pyroptosis of different cells during the PPO. Conclusively, this review provides theoretical support for the search for new strategies and new targets for the treatment of PPO by inhibiting pyroptosis and inflammation.

CoCrMo-Nanoparticles induced peri-implant osteolysis by promoting osteoblast ferroptosis via regulating Nrf2-ARE signalling pathway.

OBJECTIVES: Aseptic loosening (AL) is the most common reason of total hip arthroplasty (THA) failure and revision surgery. Osteolysis, caused by wear particles released from implant surfaces, has a vital role in AL. Although previous studies suggest that wear particles always lead to osteoblast programmed death in the process of AL, the specific mechanism remains incompletely understood and osteoblast ferroptosis maybe a new mechanism of AL. MATERIALS AND METHODS: CoCrMo nanoparticles (CoNPs) were prepared to investigate the influence of ferroptosis in osteoblasts and calvaria resorption animal models. Periprosthetic osteolytic bone tissue was collected from patients who underwent AL after THA to verify osteoblast ferroptosis. RESULTS: Our study demonstrated that CoNPs induced significant ferroptosis in osteoblasts and particles induced osteolysis (PIO) animal models. Blocking ferroptosis with specific inhibitor Ferrostatin-1 dramatically reduced particle-induced ferroptosis in vitro. Moreover, in osteoblasts, CoNPs significantly downregulated the expression of Nrf2 (nuclear factor erythroid 2-related factor 2), a core element in the antioxidant response. The overexpression of Nrf2 by siKeap1 or Nrf2 activator Oltipraz obviously upregulated antioxidant response elements (AREs) and suppressed ferroptosis in osteoblasts. Furthermore, in PIO animal models, the combined utilization of Ferrostatin-1 and Oltipraz dramatically ameliorated ferroptosis and the severity of osteolysis. CONCLUSIONS: These results indicate that CoNPs promote osteoblast ferroptosis by regulating the Nrf2-ARE signalling pathway, which suggests a new mechanism underlying PIO and represents a potential therapeutic approach for AL.

Bikini Incision Increases the Incidence of Lateral Femoral Cutaneous Nerve Injury in Direct Anterior Approach Hip Arthroplasty: A Prospective Ultrasonic, Electrophysiological, and Clinical Study.

BACKGROUND: Lateral femoral cutaneous nerve (LFCN) injury has been widely reported as one of the most common complications of direct anterior approach (DAA) hip arthroplasty. Bikini incision is considered to increase the incidence of this complication. METHODS: A prospective randomized study was conducted after including ninety-nine bikini and ninety-six longitudinal incision DAA cases from May to November 2020. The occurrence of LFCN was examined using ultrasound before and after surgery. The recovery of injury symptoms was evaluated by continuous clinical follow-up until six months, and the patients were treated with mecobalamin and/or celecoxib. Sensory conduction velocity and sensory action potential amplitude of the LFCN were measured after surgery in symptomatic patients. RESULTS: Eighty five (43.6%), sixty seven (34.4%), and forty three (22.0%) cases of LFCN were of the anterior trunk, posterior trunk, and fan types, respectively, before surgery. All one hundred ninety five patients completed the follow-up period. Fifty-seven patients had symptoms of LFCN injury, including thirty six and twenty one patients in the bikini group and longitudinal group, respectively, with significantly different incidence rates (36.4% and 21.9%, respectively; P < .05). Of these, thirty two (56.1%), thirteen (22.8%), and twelve (21.1%) cases were of the anterior trunk, posterior trunk, and fan types, respectively. Sensory conduction velocity and sensory action potential amplitude significantly decreased after surgery in both groups (P < .05). Seventeen cases showed reduction of symptoms within three months. Forty six cases showed self-recovery within six months and eleven cases showed persistent symptoms at the final follow-up. CONCLUSION: Bikini incision DAA hip arthroplasty may increase the incidence of LFCN injury, and the anterior trunk distribution type is most likely to be affected. (Clinical Trial Registration Number: CHICTR2000035107).

LDC000067 suppresses RANKL-induced osteoclastogenesis in vitro and prevents LPS-induced osteolysis in vivo.

Bone homeostasis requires a dynamic balance between osteogenesis and osteoclastogenesis, and osteolytic disorders are mainly attributed to aberrant osteoclastogenesis and bone resorption. Accumulating evidence has demonstrated that cyclin-dependent kinase 9 (CDK9) regulates some inflammatory diseases without affecting the cell cycle. Whether the specific inhibitor of CDK9, LDC000067 (abbreviated as LDC067), helps to prevent from osteolytic disorders has not been fully elucidated. Interestingly, this study demonstrated that LDC067 inhibited receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis and bone resorption in vitro, and suppressed the expression of osteoclast-related marker genes such as cathepsin K (CTSK), tartrate-resistant acid phosphatase (TRAP), dendrite cell-specific transmembrane protein (DC-STAMP), V-ATPase D2, calcitonin receptor (CTR) and nuclear factor of activated T cells cytoplasmic 1 (NFATc1). The bone protective effects of LDC067 can be partly explained by its suppression of nuclear factor-kappa B (NF-κB)-mediated NFATc1 activation via AKT signalling pathway. In keeping with the results obtained in vitro, inhibition of CDK9 with LDC067 was observed to delay subchondral osteolysis and substantially ameliorate LPS-induced osteolysis in murine calvaria. Collectively, these results highlight the positive effects of LDC067 in preventing osteolytic disorders and indicate that this CDK9 inhibitor may a promising therapeutic agent.

CDK9 attenuation exerts protective effects on catabolism and hypertrophy in chondrocytes and ameliorates osteoarthritis development.

Osteoarthritis (OA) is generally considered to be characterized by progressive articular cartilage destruction. Increasing evidence demonstrates that CDK9, which is a member of cyclin-dependent kinase family, plays a significant role in the regulation of acute and chronic inflammatory diseases. IL-1ß, a major proinflammatory cytokine, was used to establish a model of OA in vitro after stimulating chondrocytes. We found that CDK9 was highly expressed in in vitro and in vivo models of inflammation. The role of LDC000067 (abbreviated as LDC067), a specific inhibitor of CDK9, in protecting articular cartilage from immune response has not been fully clarified. Intriguingly, in this study, we demonstrated that LDC067 prevented IL-1ß-induced production of metalloproteinases (MMPs) and inflammatory cytokines, including MMP3, MMP9, MMP13, IL-6, IL-8 and TNF-ɑ. Furthermore, we revealed that LDC067 inhibited IL-1ß-induced NF-κB signaling pathway activation in chondrocytes. The inhibition of CDK9 could also delay cartilage degeneration in an anterior cruciate ligament transection (ACLT) mouse model in vivo. Taken together, these results highlighted the significance of this CDK9 inhibitor in preventing cartilage destruction and indicated that LDC067 might serve as a potential therapeutic agent for OA.

Effect of Celecoxib on Surgical Site Inflammation after Total Knee Arthroplasty: A Randomized Controlled Study.

OBJECTIVE: To evaluate the anti-inflammatory effectiveness of celecoxib and its effect on the rehabilitation of joint function after total knee arthroplasty. METHODS: 72 patients presented between 2016 and 2017 and were divided into two groups. The experimental group was given 200 mg celecoxib twice daily with tramadol hydrochloride 50 mg twice daily (as required); the control group was given tramadol hydrochloride 50 mg twice daily for 6 weeks from the first day after total knee arthroplasty. Skin temperature around the knee was measured 1 day before surgery, on postoperative days 1 and 3, and at weeks 1, 2, and 6. Inflammatory markers (white blood cell count, C-reactive protein, erythrocyte sedimentation rate, and interleukin-6) were measured preoperatively, on postoperative day 3, and at weeks 1 and 6. Knee Society Score was recorded preoperatively and at postoperative weeks 1, 2, and 6. RESULTS: Except for preoperative skin temperature, the recorded skin temperatures of the experimental group were significantly different compared to those of the control group (p = 0.001, 0.024, 0.030, 0.041, 0.047, respectively). Levels of C-reactive protein were significantly different at the 1st and the 6th week after surgery, differing by 19.3 ± 4.64 mg/L (p < 0.001) and 2.6 ± 0.92 mg/L (p = 0.006). Levels of interleukin-6 showed a significant difference of 6.61 ± 2.36 pg/mL (p = 0.007) at the 1st week after surgery. Until the 6th week after surgery, the erythrocyte sedimentation rate in the experimental group and the control group differed by 17 ± 4.6 mm/h (p = 0.001). CONCLUSIONS: Celecoxib has a significant inhibitory effect on postoperative aseptic inflammation.

Oxymatrine exerts protective effects on osteoarthritis via modulating chondrocyte homoeostasis and suppressing osteoclastogenesis.

Osteoarthritis (OA) is a common degenerative disease characterized by the progressive destruction both articular cartilage and the subchondral bone. The agents that can effectively suppress chondrocyte degradation and subchondral bone loss are crucial for the prevention and treatment of OA. Oxymatrine (OMT) is a natural compound with anti-inflammatory and antitumour properties. We found that OMT exhibited a strong inhibitory effect on LPS-induced chondrocyte inflammation and catabolism. To further support our results, fresh human cartilage explants were treated with LPS to establish an ex vivo degradation model, and the results revealed that OMT inhibited the catabolic events of LPS-stimulated human cartilage and substantially attenuated the degradation of articular cartilage ex vivo. As subchondral bone remodelling is involved in OA progression, and osteoclasts are a unique cell type in bone resorption, we investigated the effects of OMT on osteoclastogenesis, and the results demonstrated that OMT suppresses RANKL-induced osteoclastogenesis by suppressing the RANKL-induced NFATc1 and c-fos signalling pathway in vitro. Further, we found that the anti-inflammatory and anti-osteoclastic effects of oxymatrine are mediated via the inhibition of the NF-κB and MAPK pathways. In animal studies, OMT suppressed the ACLT-induced cartilage degradation, and TUNEL assays further confirmed the protective effect of OMT on chondrocyte apoptosis. MicroCT analysis revealed that OMT had an attenuating effect on ACLT-induced subchondral bone loss in vivo. Taken together, these results show that OMT interferes with the vicious cycle associated with OA and may be a potential therapeutic agent for abnormal subchondral bone loss and cartilage degradation in osteoarthritis.

[Expression of Sclerostin in medial and lateral subchondral bone of the varus osteoarthritic knee plateau].

Objective: To study the expression difference of Sclerostin in the medial and lateral subchondral bone of the varus osteoarthritic knee plateau. Methods: The tibial plateau was obtained from 20 patients with varus knee osteoarthritis receiving total knee arthroplasty from March to October 2015. There were 8 males and 12 females with an average age of 67.8 years (range, 61-78 years). The mean course of osteoarthritis was 3.2 years (range, 2-5 years). Before operation, the varus angle was 12.0-25.5° (mean, 17.6°) on the X-ray film. Five cases were rated as grade III and 15 cases as grade IV according to Kellgren-Lawrance classification. Micro-CT scan was performed on the medial and lateral subchondral bone to compare the changes of bone structure; bone volume/total volume (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), structure model index (SMI), and the trabecular separation (Tb.Sp) were measured. Immunohistochemistry and real-time fluorescent quantitative PCR were used to test the expressions of Sclerostin protein and sost gene. Results: Micro-CT showed that BV/TV, Tb.N, and Tb.Th significantly increased in the medial subchondral bone when compared with the lateral part ( P<0.05), but SMI and Tb.Sp significantly reduced ( P<0.05). Real-time fluorescent quantitative PCR detection showed that sost gene expression level in the medial subchondral bone (1.000) was significantly lower than that in the lateral part (4.157±2.790) ( t=2.371, P=0.040). The percentage of Sclerostin positive cells in the lateral subchondral bone (52.00%±0.19%) was significantly higher than that in the medial subchondral bone (7.20%±0.04%) ( t=5.094, P=0.005). Conclusion: Sclerostin plays an important role in the subchondral bone remodeling of the varus osteoarthritic knee. And the low expression of Sclerostin may be an important factor to promote bone remodeling and aggravate knee deformity.

[Comparative study on differences in acetabular position during total hip arthroplasty between by direct anterior approach and by posterolateral approach].

Objective: To compare the differences in acetabular position during total hip arthroplasty (THA) between by direct anterior approach and by posterolateral approach. Methods: Between December 2008 and December 2015, 102 patients undergoing THA were included in the study. THA was performed by anterior approach in 51 cases (anterior group) and by posterolateral approach in 51 cases (posterolateral group). There was no significant difference in gender, age, body mass index, side, and cause of illness between 2 groups ( P>0.05), with comparability. The acetabular abduction angle and anteversion angel were measured on the X-ray film at 1 day after operation to evaluate whether the acetabular prosthesis was displaced in the safe zone. Results: The acetabular abduction angle was (42.28±5.77)° in the anterior group and was (43.93±7.44)° in the posterolateral group, showing no significant difference ( t=1.30, P=0.19). The acetabular anteversion angle was (21.14±5.17)° in the anterior group and was (21.05±4.10)° in the posterolateral group, showing no significant difference ( t=0.05, P=0.96). The ratio in the target safe zone of the acetabular abduction angle in the anterior group and the posterolateral group were 88.2% (45/51) and 84.3% (43/51) respectively, showing no significant difference ( χ2=0.33, P=0.56). The ratio in the target safe zone of the acetabular anteversion was 80.4% (41/51) in the anterior group and was 82.4% (42/51) in the posterolateral group, showing no significant difference between 2 groups ( χ2=0.06, P=0.79). The ratio in the target safe zone of both the abduction and anteversion angel was 70.6% (36/51) in the anterior group and was 68.6% (35/51) in the posterolateral group, showing no significant difference ( χ2=0.05, P=0.82). Conclusion: There is no differences in the acetabulum position during THA between by direct anterior approach and posterolateral approach.

[Mid-term effectiveness of total hip arthroplasty by direct anterior approach].

Objective: To retrospectively compare the mid-term effectiveness between by direct anterior approach (DAA) and by posterolateral approach in total hip arthroplasty (THA). Methods: Between January 2009 and December 2010, 110 patients (110 hips) treated with THA and followed up more than 5 years were chosen in the study. THA was performed on 55 patients by DAA (DAA group), and on 55 patients by posterolateral approach (PL group). There was no significant difference in gender, age, body mass index, types of hip joint disease, and preoperative Harris score between 2 groups ( P>0.05). The operation time, amount of bleeding, length of hospital stay, postoperative complications, and the Harris scores were recorded and compared. Results: There was no significant difference in operation time and length of hospital stay between 2 groups ( t=0.145， P=0.876; t=1.305, P=0.093). The amount of bleeding was significantly less in DAA group than in PL group ( t=2.314, P=0.032). All patients were followed up 5-7 years (mean, 5.97 years). Complications happened in 5 cases (9.1%) of DAA group and in 3 cases (5.5%) of PL group, and there was no significant difference in the incidence of complications between 2 groups ( χ2=0.539， P=0.463). There was significant difference in Harris scores at 6 months after operation between 2 groups ( t=2.296, P=0.014), but no significant difference was found in Harris score at 1 year and 5 years between 2 groups ( t=1.375, P=0.130; t=0.905, P=0.087). Further analysis, at 6 months after operation, the joint function score in DAA group was significantly higher than that in PL group ( t=1.087, P=0.034), while there was no significant difference in the pain score and range of motion score between 2 groups ( t=1.872, P=0.760; t=1.059, P=0.091). Conclusion: THA by DAA has the advantages of less bleeding and faster recovery. The short-term effectiveness is superior to the THA by traditional posterolateral approach, but there is no obvious advantage in the mid-term effectiveness.

[OBSERVATION OF EFFECTIVENESS OF HIP RESURFACING ARTHROPLASTY IN TREATMENT OF OSTEONECROSIS OF FEMORAL HEAD IN YOUNG AND MIDDLE-AGED PATIENTS].

OBJECTIVE: To evaluate the clinical and radiographic outcomes of hip resurfacing arthroplasty (HRA) for treating osteonecrosis of the femoral head (ONFH) in young and middle-aged patients. METHODS: Between January 2008 and April 2009, 34 patients with ONFH underwent HRA. There were 19 males and 15 females with an average age of 54 years (range, 33-59 years). Of 34 cases, 16 left hips and 18 right hips were involved, including 9 cases of alcohol-induced ONFH, 8 cases of steroid-induced ONFH, 7 cases of traumatic ONFH, and 10 cases of unexplained ONFH. According to modified Ficat classification system, 26 hips were rated as stage III, and 8 hips as stage IV. The Harris hip score (HHS) and modified University of California, Los Angeles (UCLA) activity score were used to evaluate the clinical results. Migration of prosthesis was assessed on the anteroposterior radiographs. The abduction angle was measured on the acetabular side. On the femoral side, varus-valgus shift was determined by measurement of stem-shaft angle. The axial collapse of femoral component was assessed with the component-lateral cortex ratio. RESULTS: Healing of incision by first intention was achieved in all patients without complications of infection and thrombosis of deep vein of lower extremities. Thirty-two patients were followed up 78 months on average (range, 70-84 months). No implant loosening, infection, femoral neck fracture, dislocation, and inflammatory pseudotumor were observed. At last follow-up, the HHS score was significantly increased to 95.22 +/- 1.47 from preoperative 50.10 +/- 2.27 (t=1.510, P=0.008). Modified UCLA activity score was significantly increased to 7.70 +/- 1.13 from preoperative 3.90 +/- 0.90 (t=0.830, P=0.003). The abduction angle, stem-shaft angle, and compotent-lateral cortex ratio showed no significant difference between at 3 days after operation and last follow-up (P>0.05). CONCLUSION: If the indication of operation is mastered strictly, HRA may be effective in treatment for ONFH at Ficat stage III or IV in young and middle-aged patients.

The Influence of Body Mass Index and Hip Anatomy on Direct Anterior Approach Total Hip Replacement.

OBJECTIVE: To investigate the influence of body mass index (BMI) and hip anatomy on direct anterior approach (DAA) total hip replacement. SUBJECTS AND METHODS: The study is a retrospective analysis of 124 cases of DAA total hip replacement from 2009 to 2012. The BMI, the ratio of the greater trochanter (GT) and anterior superior iliac spine (ASIS) bilaterally (GT/ASIS), and the vertical distance between the ASIS and GT (AGVD) were obtained from medical records. All cases were categorized into three groups (43, 49, and 32 cases in each group, respectively) based on BMI (BMI <18.5, BMI 18.5-25, and BMI >25) or divided into two groups based on GT/ASIS (≤1.17 or >1.17) or AGVD (≤86 or >86 mm). Operating time, intraoperative bleeding, and surgical complications were compared between different groups. RESULTS: A longer average operating time, more intraoperative bleeding, and a higher rate of complications were observed in the group with the highest BMI. The complications included a case of intraoperative femur fracture, a wound hematoma, and a lateral femoral cutaneous nerve injury. The group with higher GT/ASIS had a shorter average operating time, less bleeding, and a lower complication rate than the group with lower GT/ASIS. Moreover, the group with higher AGVD showed a shorter average operating time, less bleeding, and a lower complication rate compared with the group with lower AGVD. CONCLUSION: Our study suggests that lower BMI and larger GT/ASIS and AGVD are associated with a shorter operating time, less bleeding, and a lower complication rate in DAA total hip replacement. These findings are valuable for clinicians to make the appropriate choice of surgery types for different individuals.

Lentivirus-Mediated Knockdown of CTHRC1 Inhibits Osteosarcoma Cell Proliferation and Migration.

Collagen triple helix repeat containing-1 (CTHRC1), a secreted protein, is transiently expressed in the arterial wall in response to injury, indicating that it may contribute to vascular remodeling by limiting collagen matrix deposition and promoting cell migration. Recent studies showed that it is aberrantly upregulated in most human solid tumors, yet its role in osteosarcoma remains unclear. In this study, the authors investigated the role of CTHRC1 in human osteosarcoma tumorigenesis. The authors used lentivirus-mediated short hairpin RNA (shRNA) against CTHRC1 to limit its endogenous expression in U2OS and SW1353 cells. Interestingly, they found that depletion of CTHRC1 significantly inhibited cell proliferation and colony formation in U2OS and SW1353 cells. Flow cytometry assay showed that knockdown of CTHRC1 increased the cell percentage of G0/G1 phase, resulting in cell cycle arrest in U2OS cells. Moreover, CTHRC1 silencing induced the cell cycle arrest by a decrease in the cell percentage in G0/G1 phase and increased in G2/M phase in SW1353 cells. In addition, crystal violet staining suggested CTHRC1 silencing inhibited migration of U2OS and SW1353 cells. These results demonstrated that CTHRC1 might play an important role in osteosarcoma progression.

A comparative study of two methods for treating type III tibial eminence avulsion fracture in adults.

PURPOSE: Suture fixation is mostly used in arthroscopic treatment of tibial eminence avulsion fractures. However, no clinical studies of metal cable fixation have been reported. We hypothesised that cable fixation can provide equal stability and clinical outcome compared with Ethibond sutures. METHODS: Between 2007 and 2008, we treated 42 patients of adult type III tibial eminence avulsion fractures. Twenty-three patients were male, and 19 were female. All patients were confirmed by radiographs, MRI, and arthroscopy during surgery. Ligament injury and meniscus tears were excluded from this study. Twenty-two patients were treated with No. 2 Ethibond suture fixation (group I), and 20 were treated with cable fixation under arthroscopy (group II). Follow-up assessments included imaging evaluation, Lysholm knee score, International Knee Documentation Committee (IKDC) classification, and the Lachman test. RESULTS: Bone union was found in radiographic evaluation in all patients within 3 months. At the last follow-up, there was neither extension nor flexion limitation in any patient. There were no significant differences in the Lysholm score between the two groups at follow-up. All 42 patients were classified by the IKDC as normal or nearly normal. Stability based on the Lachman test showed two patients of grade II laxity in group I. At the final follow-up, all 42 patients had returned to their pre-injury activities. CONCLUSIONS: Cable fixation to treat type III tibial eminence avulsion fracture can provide a clinical outcome equal to that of Ethibond sutures. LEVEL OF EVIDENCE: IV.