Tumour extracellular vesicles and particles induce liver metabolic dysfunction.

Cancer alters the function of multiple organs beyond those targeted by metastasis1,2. Here we show that inflammation, fatty liver and dysregulated metabolism are hallmarks of systemically affected livers in mouse models and in patients with extrahepatic metastasis. We identified tumour-derived extracellular vesicles and particles (EVPs) as crucial mediators of cancer-induced hepatic reprogramming, which could be reversed by reducing tumour EVP secretion via depletion of Rab27a. All EVP subpopulations, exosomes and principally exomeres, could dysregulate hepatic function. The fatty acid cargo of tumour EVPs-particularly palmitic acid-induced secretion of tumour necrosis factor (TNF) by Kupffer cells, generating a pro-inflammatory microenvironment, suppressing fatty acid metabolism and oxidative phosphorylation, and promoting fatty liver formation. Notably, Kupffer cell ablation or TNF blockade markedly decreased tumour-induced fatty liver generation. Tumour implantation or pre-treatment with tumour EVPs diminished cytochrome P450 gene expression and attenuated drug metabolism in a TNF-dependent manner. We also observed fatty liver and decreased cytochrome P450 expression at diagnosis in tumour-free livers of patients with pancreatic cancer who later developed extrahepatic metastasis, highlighting the clinical relevance of our findings. Notably, tumour EVP education enhanced side effects of chemotherapy, including bone marrow suppression and cardiotoxicity, suggesting that metabolic reprogramming of the liver by tumour-derived EVPs may limit chemotherapy tolerance in patients with cancer. Our results reveal how tumour-derived EVPs dysregulate hepatic function and their targetable potential, alongside TNF inhibition, for preventing fatty liver formation and enhancing the efficacy of chemotherapy.

A multifunctional injectable, self-healing, and adhesive hydrogel-based wound dressing stimulated diabetic wound healing with combined reactive oxygen species scavenging, hyperglycemia reducing, and bacteria-killing abilities.

The proficient handling of diabetic wounds, a rising issue coinciding with the global escalation of diabetes cases, poses significant clinical difficulties. A range of biofunctional dressings have been engineered and produced to expedite the healing process of diabetic wounds. This study proposes a multifunctional hydrogel dressing for diabetic wound healing, which is composed of Polyvinyl Alcohol (PVA) and N1-(4-boronobenzyl)-N3-(4-boronophenyl)-N1, N1, N3, N3-teramethylpropane-1, 3-diaminium (TSPBA), and a dual-drug loaded Gelatin methacryloyl (GM) microgel. The GM microgel is loaded with sodium fusidate (SF) and nanoliposomes (LP) that contain metformin hydrochloride (MH). Notably, adhesive and self-healing properties the hydrogel enhance their therapeutic potential and ease of application. In vitro assessments indicate that SF-infused hydrogel can eliminate more than 98% of bacteria within 24 h and maintain a sustained release over 15 days. Additionally, MH incorporated within the hydrogel has demonstrated effective glucose level regulation for a duration exceeding 15 days. The hydrogel demonstrates a sustained ability to neutralize ROS throughout the entire healing process, predominantly by electron donation and sequestration. This multifunctional hydrogel dressing, which integrated biological functions of efficient bactericidal activity against both MSSA and MRSA strains, blood glucose modulation, and control of active oxygen levels, has successfully promoted the healing of diabetic wounds in rats in 14 days. The hydrogel dressing exhibited significant effectiveness in facilitating the healing process of diabetic wounds, highlighting its considerable promise for clinical translation.

Analysis of the incidence and risk factors of blood transfusion in total knee revision: a retrospective nationwide inpatient sample database study.

OBJECTIVE: This study sought to determine the incidence and risk factors of blood transfusion among patients undergoing total knee revision (TKR) using a nationwide database. METHODS: A retrospective data analysis was conducted based on the Nationwide Inpatient Sample (NIS), enrolling patients who underwent TKR from 2010 to 2019 with complete information. The patients were divided into two groups based on whether they received blood transfusion or not. The demographic characteristics (race, sex, and age), length of stay (LOS), total charge of hospitalization, hospital characteristics (admission type, insurance type, bed size, teaching status, location, and region of hospital), hospital mortality, comorbidities, and perioperative complications were analyzed. Finally, we conducted univariate and multivariate logistic regression to identify factors that were associated with TKR patients to require blood transfusion. RESULTS: The NIS database included 115,072 patients who underwent TKR. Among them, 14,899 patients received blood transfusion, and the incidence of blood transfusion was 13.0%. There was a dramatic decrease in the incidence over the years from 2010 to 2019, dropping from 20.4 to 6.5%. TKR patients requiring transfusions had experienced longer LOS, incurred higher total medical expenses, utilized Medicare more frequently, and had increased in-hospital mortality rates (all P < 0.001). Independent predictors for blood transfusion included advanced age, female gender, iron-deficiency anemia, rheumatoid disease, chronic blood loss anemia, congestive heart failure, coagulopathy, uncomplicated diabetes, lymphoma, fluid and electrolyte disorders, metastatic carcinoma, other neurological diseases, paralysis, peripheral vascular disorders, pulmonary circulation disorders, renal failure, valvular disease, and weight loss. In addition, risk factors for transfusion in TKR surgery included sepsis, acute myocardial infarction, deep vein thrombosis, pulmonary embolism, gastrointestinal bleeding, heart failure, renal insufficiency, pneumonia, wound infection, lower limb nerve injury, hemorrhage/seroma/hematoma, wound rupture/non healing, urinary tract infection, acute renal failure, and postoperative delirium. CONCLUSIONS: Our findings highlight the importance of recognizing the risk factors of blood transfusion in TKR to reduce the occurrence of adverse events.

A retrospective analysis of the incidence of postoperative delirium and the importance of database selection for its definition.

BACKGROUND: Postoperative delirium (POD) is a common complication after major surgery, resulting in various adverse reactions. However, incidence and risk factors associated with POD after shoulder arthroplasty (SA) have not been well studied using a large-scale national database. METHODS: A retrospective database analysis was performed based on the Nationwide Inpatient Sample (NIS) from 2005 to 2014, the largest fully paid hospital care database in the United States. Patients undergoing SA were included. The patient's demographics, comorbidities, length of stay (LOS), total costs, type of insurance, type of hospital, in-hospital mortality, and medical and surgical perioperative complications were assessed. RESULTS: A total of 115,147 SA patients were obtained from the NIS database. The general incidence of delirium after SA was 0.89%, peaking in 2010. Patients with delirium after SA had more comorbidities, prolonged LOS, increased hospitalization costs, and higher in-hospital mortality (P < 0.0001). These patients were associated with medical complications during hospitalization, including acute renal failure, acute myocardial infarction, pneumonia, pulmonary embolism, stroke, urinary tract infection, sepsis, continuous invasive mechanical ventilation, blood transfusion, and overall perioperative complications. Risk factors associated with POD include advanced age, neurological disease, depression, psychosis, fluid and electrolyte disturbances, and renal failure. Protective factors include elective hospital admissions and private insurance. CONCLUSION: The incidence of delirium after SA is relatively low. Delirium after SA was associated with increased comorbidities, LOS, overall costs, Medicare coverage, mortality, and perioperative complications. Studying risk factors for POD can help ensure appropriate management and mitigate its consequences. Meanwhile, we found some limitations of this type of research and the need to establish a country-based POD database, including further clearly defining the diagnostic criteria for POD, investigating risk factors and continuing to collect data after discharge (30 days or more), so as to further improve patient preoperative optimization and management.

Comparison of the plantar pressure distribution and mechanical alignment in patients with varus knee osteoarthritis following high tibial osteotomy.

PURPOSE: The changes in the lower limb alignment were vitally important after high tibial osteotomy (HTO). Therefore, the purpose of present study was to analyze the characteristics of plantar pressure distribution after HTO, and to investigate the effect of plantar pressure distribution on postoperative limb alignment. METHODS: Between May 2020 and April 2021, varus knee patients undergoing HTO were evaluated in the present study. The peak pressure of plantar regions, medial-lateral pressure ratio (MLPR), foot progression angle (FTA), anteroposterior COP (AP-COP), lateral symmetry of COP (LS-COP), and the radiographic parameters were evaluated preoperatively and at the final follow-up. Compared among the slight valgus (SV), moderate valgus (MV) and large valgus (LV) groups at the final follow-up, the peak pressure of HM, HC and M5 regions, and the MLPR were compared; the Knee Injury and Osteoarthritis Outcome Score4 (KOOS4) including four subscales, and the American of orthopedic foot and ankle society (AOFAS) were evaluated. RESULTS: The WBL%, HKA and TPI angle changed significantly after HTO (P < 0.001). The preoperative group exhibited a lower peak pressure in the HM region (P < 0.05) and higher peak pressure in the M5 region (P < 0.05); the pre- and postoperative groups exhibited a lower peak pressure in the HC region (P < 0.05); the rearfoot MLPR was significantly lower and LS-COP was significantly higher in the preoperative group (P = 0.017 in MLPR and 0.031 in LS-COP, respectively). Comparison among the SV, MV and LV groups, the SV group indicated a lower peak pressure in the HM region (P = 0.036), and a lower MLPR in the rearfoot (P = 0.033). The KOOS Sport/Re score in the MV and LV groups increased significantly compared with the SV group (P = 0.042). CONCLUSION: Plantar pressure distribution during the stance phase in patients with varus knee OA following HTO exhibited a more medialized rearfoot plantar pressure distribution pattern than that before surgery. Compared with the small valgus alignment, a moderate to large valgus alignment allows patients to walk with a more even medial and lateral plantar pressure distribution, which is more similar to healthy adults.

Comparisons of in-hospital complications between total hip arthroplasty and hip resurfacing arthroplasty.

BACKGROUND: Hip resurfacing arthroplasty (HRA) is a less common but effective alternative method to total hip arthroplasty (THA) for hip reconstruction. In this study, we investigated the incidences of in-hospital complications between patients who had been subjected to THA and HRA. METHODS: The National Inpatient Sample data that had been recorded from 2005 to 2014 was used in this study. Based on the International Classification of Disease, Ninth Revision, Clinical Modification, patients who underwent THA or HRA were included. Data on demographics, preoperative comorbidities, length of hospital stay, total charges, and in-hospital mortality and complications were compared. Multiple logistic regression analysis was used to determine whether different surgical options are independent risk factors for postoperative complications. RESULTS: A total of 537,506 THAs and 9,744 HRAs were obtained from the NIS database. Patients who had been subjected to HRA exhibited less preoperative comorbidity rates, shorter length of stay and extra hospital charges. Moreover, HRA was associated with more in-hospital prosthesis loosening. Notably, patients who underwent HRA were younger and presented less preoperative comorbidities but did not show lower incidences in most complications. CONCLUSIONS: The popularity of HRA gradually reduced from the year 2005 to 2014. Patients who underwent HRA were more likely to be younger, male, have less comorbidities and spend more money on medical costs. The risk of in-hospital prosthesis loosening after HRA was higher. The HRA-associated advantages with regards to most in-hospital complications were not markedly different from those of THA. In-hospital complications of HRA deserve more attention from surgeons.

Delayed surgery is associated with adverse outcomes in patients with hip fracture undergoing hip arthroplasty.

BACKGROUND: Hip arthroplasty (HA) is one of the most effective procedures for patients with hip fractures. The timing of surgery played a significant role in the short-term outcome for these patients, but conflicting evidence has been found. METHODS: The Nationwide Inpatient Sample database was investigated from 2002 to 2014 and identified 247,377 patients with hip fractures undergoing HA. The sample was stratified into ultra-early (0 day), early (1-2 days) and delayed (3-14 days) groups based on time to surgery. Yearly trends, postoperative surgical and medical complications, postoperative length of hospital stay (POS) and total costs were compared after propensity scores were matched between groups by demographics and comorbidity. RESULTS: From 2002 to 2014, the percentage of hip fracture patients who underwent HA increased from 30.61 to 31.98%. Early surgery groups showed fewer medical complications but higher surgical complications. However, specific complication evaluation showed both ultra-early and early groups decreased most of the surgery and medical complications with increasing post hemorrhagic anemia and fever. Medical complications were also reduced in the ultra-early group, but surgical complications increased. Early surgery groups reduced the POS by 0.90 to 1.05 days and total hospital charges by 32.6 to 44.9 percent than delayed surgery groups. Ultra-early surgery showed no benefit from POS than early group, but reduced total hospital charges by 12.2 percent. CONCLUSION: HA surgery performed within 2 days showed more beneficial effects on adverse events than delayed surgery. But surgeons should be cognizant of the potential increased risks of mechanical complications and post-hemorrhagic anemia.

Patients receiving knee arthroplasty with pre-existing long-term aspirin use suffer lower risk of perioperative complications but feel more postoperative pain.

BACKGROUND: Aspirin has gained increasing use-popularity on account of its multiple benefits. The present study aimed to investigate how a pre-existing long-term aspirin use (L-AU) would affect perioperative complications and postoperative pain in primary total knee arthroplasty (TKA) patients. METHODS: Utilizing the National Inpatient Sample (NIS) database, primary TKAs were divided into L-AU and non-L-AU cohorts. Propensity score matching (PSM) was performed to match the demographics and comorbidities characteristics. Chi-square test and logistic regression analysis were calculated for the risk analysis of perioperative complications and postoperative pain. RESULTS: The popularity of L-AU in primary TKA patients had significantly increased from 1.5% (2005) to 10.5% (2014) in the U.S. Pre-existing L-AU was associated with decreased risks of most perioperative complications (any complication, adjusted odds ratio [aOR]: 0.920), in-hospital mortality (aOR: 0.367), and shortened hospitalization stay (LOS) (aOR: 0.647), etc. However, L-AU was recognized as a risk factor of acute postoperative pain (aOR: 1.466) and slightly higher total cost (aOR: 1.047). CONCLUSIONS: For the first time in the present study, it is found that pre-existing long-term aspirin use is benefic in reducing perioperative complication risk. According to this finding, future research might determine the optimal pre-operational taking time and dose of aspirin use. Consequently, orthopedic surgeons and healthcare providers could provide this valuable advice to specific patients prior to a planned arthroplasty and subsequently gain feasible clinical benefits.

Spontaneous resolution of asymptomatic alumina matrix composite ceramic liner dissociation: a case report.

BACKGROUND: Total hip arthroplasty(THA)is widely used to treat end-stage hip disorders. Ceramic-on-ceramic total hip prostheses are widely used because of their durability. Alumina matrix composite (AMC), known as the fourth-generation ceramics, reduces implant fracture and wear rate compared to their predecessors. However, ceramic acetabular liner dissociation is a complication that necessitates revision of the AMC prostheses. To date, only few cases of AMC liner dissociation have been reported and all of which have been treated with revision surgery. Therefore, the prognosis of non-operated AMC liner dissociation remains unknown so far. CASE PRESENTATION: A 57-year-old man with avascular necrosis of the femoral head was treated with THA, wherein a Pinnacle® (DePuy, J&J, Warsaw, IN) acetabular cup and AMC liner were implanted. Intraoperative examination confirmed proper seating of the liner, whereas the initial postoperative radiograph revealed liner dissociation. The patient refused surgical revision due to the absence of symptoms and was discharged and followed-up. The patient made an uneventful recovery, and radiographic follow-up at 6-month post-operation showed that the liner was re-seated to its right position. No clinical or radiographic anomaly was found at the 15-month of postoperative follow-up. CONCLUSIONS: Here, we report an unprecedented case of AMC ceramic liner dissociation with spontaneous resolution. This case shows that ceramic liner dissociation could be asymptomatic, and careful postoperative examination of the patient is important. Spontaneous resolution is possible, but the underlying mechanism and the eligible patient to benefit from it must be investigated. Before clarifying these questions, revision surgery should be the first-line treatment.

Influence of frailty and its interaction with comorbidity on outcomes among total joint replacement.

BACKGROUND: Patients with frailty get more and more attention in clinical practice. Yet, no large-scale studies have explored the impact of frailty on the perioperative acute medical and surgical complications following TJA. what is more, comorbid diseases may lead, at least additively, to the development of frailty. There also no studies to find the possible interaction between comorbidity and frailty on the postoperative complications after TJA. METHODS: Discharge data of 2,029,843 patients who underwent TJA from 2005 to 2014 from the National Inpatient Sample (NIS) database, which was analyzed using cross-tabulations and multivariate regression modeling. Frailty was defined based on frailty-defining diagnosis clusters from frailty-defining diagnosis indicator of Johns Hopkins Adjusted Clinical Groups. RESULTS: Among patients who underwent total joint replacement surgeries, 50,385 (2.5%) were identified as frail. Frailty is highly associated with old age, especially for those over the age of 80, meanwhile females and black races have a high Charlson comorbidity index (CCI) of ≥ 3, together with emergency/urgent admission and teaching hospital. While comorbidity is associated with greater odds of acute medical complications, and frailty has a better predictive effect on in-hospital deaths, acute surgical complications. Furthermore, frailty did not show an enhancement in the predictive power of the Charlson comorbidity score for postoperative complications or in-hospital deaths but postoperative LOS and hospitalization costs. CONCLUSION: Frailty can be used to independently predicted postoperative surgical and medical complications, which also has a synergistic interaction with comorbidity for patients who are preparing to undergo TJA.

Complications of primary total hip arthroplasty among patients with rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and primary osteoarthritis.

BACKGROUND: Limited information exists comparing the perioperative complications of the different inflammatory arthropathies (IAs) after total hip arthroplasty (THA). Our study was aimed to (1) compare perioperative complications and (2) determine the most common complications between the different IA subtypes compared with patients with primary osteoarthritis (OA) undergoing primary THA and (3) find whether the difference in postoperative complications also exists between different IA after THA. METHODS: The Nationwide Inpatient Sample (NIS) was used to identify patients with Rheumatoid arthritis (RA), psoriatic arthritis, ankylosing spondylitis (AS), and primary OA undergoing unilateral THA between 2005 and 2014. Preoperative diagnosis, comorbidities, and postoperative complications were determined using the International Classification of Disease Clinical Modification version 9 codes. The prevalence of perioperative complications was compared between patients with IA and primary OA and between patients with different IA. RESULTS: When compared with patients with primary OA, patients with RA had significantly more postoperative surgical and medical complications. Yet there are just several medical complications differences exist between PA and primary OA or AS and primary OA, including stroke and acute renal failure for psoriatic arthritis and urinary tract infection and pneumonia for AS. What is more, there were also several differences in perioperative medical complications seen in patients with different IA. CONCLUSION: Except for patients with RA, the differences in perioperative complications was small between patients with IA and primary OA and between patients with different types of IA.

Analysis of peripheral bone reconstruction after the failure of hip osteonecrosis treatment with porous tantalum rod implantation.

PURPOSE: Failure of porous tantalum rod (PTR) implantation in treating early osteonecrosis of femoral head (ONFH) has been frequently reported, but the underlying mechanism remains uncertain, which raised the concern of its efficacy. The study aimed to discuss the underlying mechanism from the perspectives of bone reconstruction and pathological changes. METHODS: Five patients with PTR implantation experienced total hip arthroplasty (THA) due to recurrent pain, whose femoral heads were collected as "tantalum group." Normal (fracture) and necrotic femoral heads were respectively collected (both n = 5) after THA. The bone quality and structure, biomechanical properties, and histopathological features were analyzed by micro-CT scanning, mechanical measurement, and histological examination. RESULTS: Both the tantalum group and necrotic group had significantly poorer bone quantity and quality than the normal group. Three-dimensional imaging reconstruction showed that the trabeculae of the tantalum group were poorest in quality. Significant differences in terms of bone quality, structure, and biomechanical properties were present between the inside and outside regions around PTR, which revealed abnormal bone reconstruction. Biomechanical analysis revealed inferior properties in the tantalum group and necrosis group. H&E staining demonstrated neutrophil infiltration among the peripheral trabeculae around PTR, and the inflammation cells were significantly more abundant than that in the normal and necrosis groups. CONCLUSION: Abnormal bone reconstruction around PTR was an important cause for failure of PTR implantation in the treatment of ONFH, which was related to biomechanical stress distribution and chronic inflammation infiltration. Insufficient biomechanical support and inflammatory trabeculae edema might account for the recurrent pain.

Incidence and risk factors associated with hospital-acquired pressure ulcers following total hip arthroplasty: A retrospective nationwide inpatient sample database study.

AIM: To examine the incidence and risk factors associated with hospital-acquired pressure ulcers (HAPUs) following total hip arthroplasty (THA) using a large-scale national database. MATERIAL AND METHODS: A retrospective database analysis was performed based on Nationwide Inpatient Sample (NIS) from 2005 to 2014. Patients who underwent THA were included. Patient demographics, hospital characteristics, length of stay (LOS), total charges during hospitalization, in-hospital mortality, preoperative comorbidities, and perioperative complications were assessed. RESULTS: The general incidence of HAPUs after THA was 0.05%, with a fluctuating trend annually. Patients suffered from HAPUs were older, less likely through elective admission, more likely in large hospital, more usage of Medicare, and less possibly paying via Private insurance. Additionally, the occurrence of HAPUs was associated with more preoperative comorbidities, longer LOS, extra total charges, and higher in-hospital mortality. Risk factors associated with HAPUs included advanced age (≥75 years), large hospital, multiple comorbidities (n ≥ 3), diabetes with chronic complications, drug abuse, liver disease, fluid and electrolyte disorders, metastatic cancer, peripheral vascular disorders, psychoses, chronic renal failure, peptic ulcer disease, and weight loss. Besides, HAPUs were associated with inflammatory arthritis and femoral neck fracture (compared with primary/secondary osteoarthritis), frailty/senility, osteoporosis, acute renal failure, pneumonia, postoperative delirium, urinary tract infection, deep vein thrombosis, sepsis/septicemia, wound dehiscence/non-healing surgical wound, periprosthetic joint infection, and mechanical prosthesis-related complications. CONCLUSION: It is beneficial to study the risk factors associated with HAPUs after THA to ensure the preventive management and optimize outcomes although a low incidence was identified.

Measurement of femoral posterior condylar offset and posterior tibial slope in normal knees based on 3D reconstruction.

BACKGROUND: Femoral posterior condylar offset (PCO) and posterior tibial slope (PTS) are important for postoperative range of motion after total knee arthroplasty (TKA). However, normative data of PCO and PTS and the correlation between them among healthy populations remain to be elucidated. The purpose of this study was to determine PCO and PTS in normal knees, and to identify the correlation between them. METHODS: Eighty healthy volunteers were recruited. CT scans were performed followed by three-dimensional reconstruction. PCO and PTS were measured and analyzed, as well as the correlation between them. RESULTS: PTS averaged 6.78° and 6.11°, on the medial and lateral side respectively (P = 0.002). Medial PCO was greater than lateral (29.2 vs. 23.8 mm, P <  0.001). Both medial and lateral PCO of male were larger than female. On the contrary, male medial PTS was smaller than female, while there was no significant difference of lateral PTS between genders. There was an inverse correlation between medial PCO and PTS, but not lateral. CONCLUSIONS: Significant differences exhibited between medial and lateral compartments, genders, and among individuals. An inverse correlation exists between PCO and PTS in the medial compartment. These results improve our understanding of the morphology and biomechanics of normal knees, and subsequently for optimising prosthetic design and surgical techniques.

Intra-Articular Mesenchymal Stromal Cell Injections Are No Different From Placebo in the Treatment of Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

PURPOSE: To evaluate the efficacy and safety of intra-articular mesenchymal stromal cells (MSCs) injections for knee osteoarthritis (OA) treatment. METHODS: We performed a systematic literature search in PubMed, Embase, Scopus, and the Cochrane Library through April 2020 to identify level I randomized controlled trials (RCTs) that evaluated the clinical efficacy of MSCs versus control treatments for knee OA. Outcomes were analyzed on an intention-to-treat basis with random-effects models. RESULTS: A total of 13 RCTs were included in the meta-analysis. Compared with placebo, there was no significant difference in VAS for pain (mean difference [MD] 1.62, 95% confidence interval [CI -0.60 to 3.85), WOMAC pain score (MD 1.88, 95% CI -0.21 to 3.98), WOMAC function score (MD -0.67, 95% CI -6.54 to 5.19), or WOMAC stiffness score (MD 0.64, 95% CI -0.86 to 2.14) for MSCs. Moreover, the smallest treatment effect of VAS for pain, WOMAC pain score, WOMAC function score, and WOMAC stiffness score did not exceed the minimum clinically important difference (MCID). Additionally, there was no significant difference in percentage of patients crossing the MCID threshold between MSC and placebo groups for VAS for pain (relative risk [RR] 0.93, 95% CI 0.55 to 1.57) or WOMAC total score (RR 0.40, 95% CI 0.13 to 1.21). Compared with hyaluronic acid (HA), MSC injection was associated with significantly better improvement in VAS for pain (MD 2.00, 95% CI 0.94 to 3.07), WOMAC pain score (MD 4.58, 95% CI 0.49 to 8.67), WOMAC total score (MD 14.86, 95% CI 10.59 to 19.13), and WOMAC stiffness score (MD 1.85, 95% CI 0.02 to 3.69). However, the smallest treatment effect of VAS for pain, WOMAC pain score, WOMAC function score, and WOMAC stiffness score did not exceed the MCID. Moreover, there was no significant difference in percentage of patients crossing the MCID threshold between MSC and HA groups for WOMAC total score (RR 0.57, 95% CI 0.21 to 1.55). We also found that MSCs did not increase adverse events compared with HA and placebo. CONCLUSIONS: Intra-articular MSC injection was not found to be superior to placebo in pain relief and functional improvement for patients with symptomatic knee OA. However, additional direct testing and combination trials of different type of cells, doses, and number of injections of MSCs are required to further enhance clinical decision making for people with symptomatic knee OA. LEVEL OF EVIDENCE: I, meta-analysis of level I studies.

Joint motion of bipolar hemiarthroplasty in routine hip functional movements: a dynamic motion study.

BACKGROUND: Many motion studies have shown that the inner bearing of bipolar prostheses moves less than expected under non-weight-bearing and static weight-bearing positions, which are not routine functional movements performed postoperatively. The aim of this study was to investigate the behaviours of bipolar prostheses during normal gait and simulative squatting. METHODS: Thirty-one femoral neck fracture patients were enrolled, and fluoroscopy examinations of walking on a treadmill, simulative squatting, and non-weight-bearing abduction-adduction and flexion-extension motions were performed at an average of 40 months postoperatively. The rate of acetabular cartilage degeneration was calculated. The ranges of motion of the outer bearing and inner bearing were determined, and the O/I ratios were calculated. Clinical efficacy was assessed by HHS and EQ-5D score. RESULTS: The inner bearing moved more than the outer bearing did, with an O/I ratio of 0.81, during the normal gait examination, while the motion of the outer bearing was obviously dominant during the simulative squatting and non-weight-bearing abduction-adduction and flexion-extension examinations. The mean acetabular cartilage degeneration rate was 0.82 ± 0.54 mm/year at the follow-up. In subgroup analyses, the motion of the outer bearing decreased to some extent with the increase in acetabular wear, and the corresponding O/I ratios among the groups showed a trend of decreasing first and then increasing. The HHS and EQ-5D scores of the patients with osteolysis and femoral stem loosening were much worse than those with fixed implants. CONCLUSION: Bipolar prostheses do function as originally intended during gait, but movement primarily occurs at the outer bearing during other examinations. The motion patterns of bipolar prostheses change with the increase in acetabular wear.

Safety of the application of Rigidfix cross-pin system via different tibial tunnels for tibial fixation during anterior cruciate ligament reconstruction.

BACKGROUND: We investigate the safety of the application of the Rigidfix cross-pin system via different tibial tunnels in the tibial fixation during anterior cruciate ligament (ACL) reconstruction. METHODS: Five adult fresh cadaver knees were fixed with the Rigidfix cross-pins in the tibial fixation site during ACL reconstruction. Two different tibial tunnel groups were established: in group A, the tunnel external aperture was placed at the 25° angle of coronal section; in group B, the tunnel external aperture was placed at the 45° angle of coronal section. The guide was placed at the plane 0.5 mm below articular facet through the tibial tunnel, with three rotation positions set at 0°, 30°, and 60° slopes. The incidences of iatrogenic injuries at tibial plateau cartilage (TPC), medial collateral ligament (MCL), and patellar tendon in three different slope angles were calculated in groups A and B and the results were analyzed by using chi square test. RESULTS: The iatrogenic injuries at MCL, TPC, and patellar tendon could occur after the Rigidfix cross-pin system was placed 5 mm below tibial plateau cartilage for ACL reconstruction. The incidences of TPC injury (χ2 = 5.662, P = 0.017) and MCL injury (P = 0.048, Fisher exact probability method) were significantly lower in group A than in group B. However, the incidence of patellar tendon injury showed no significant difference between these two groups (χ2 = 0.120, P = 0.729). CONCLUSIONS: When the Rigidfix cross-pin system is used for ACL reconstruction at the tibial fixation site, the external aperture of tibial tunnel should not be placed at the excessively posterosuperior site, to avoid MCL and TPC injuries.

Efficacy of platelet-rich plasma in arthroscopic repair for discoid lateral meniscus tears.

BACKGROUND: To evaluate the clinical results of arthroscopic repair with or without platelet-rich plasma (PRP) for tears of the discoid lateral meniscus (DLM). METHODS: Twenty-nine patients with DLM tears within a stable knee were arthroscopically treated with meniscal suture repair. Of those, 14 were augmented with platelet-rich plasma (PRP), and 15 were performed without PRP augmentation. Patients were evaluated at baseline (the day before surgery) and then 12 and 24 months after the last injection. Evaluation included the Lysholm score, and Ikeuchi grade, Visual analogue score (VAS) for pain and failure rate. Failure was defined by patients developing symptoms of joint line pain, locking, swelling or requiring repeat arthroscopy. RESULTS: There was no difference in the failure rate in the PRP group (1 of 14) compared with the non-PRP group (2 of 15) (P = 0.58). Statistically significant improvement in Lysholm score, Ikeuchi grade and VAS for pain was documented at the last follow-up compared with baseline in both PRP and non-PRP group. No significantly difference was found between the PRP group and non-PRP group on Lysholm score, Ikeuchi grade and VAS for pain at the last follow-up. In the univariate analysis of each variable, younger age (P = 0.036) and longer follow-up duration (P = 0.043) were statistically associated with a better function improvement. Whereas in multivariate analysis, only younger age (P = 0.004) was significantly associated with a better function improvement. CONCLUSION: With regard to clinical evaluations in arthroscopic repair for DLM tears, PRP group had similar effect in pain relief and functional improvement to non-PRP group at mid-term follow-up. Future larger prospective studies with a longer follow-up are needed to determine whether PRP should be used with DLM repair.

Depression and Anxiety Are Risk Factors for Postoperative Pain-Related Symptoms and Complications in Patients Undergoing Primary Total Knee Arthroplasty in the United States.

BACKGROUND: The study was designed to analyze the underlying relationship between psychiatric comorbidities and postoperative outcomes in patients undergoing primary total knee arthroplasty (TKA). METHODS: We used the National Inpatient Sample data from 2002 to 2014. On the basis of the International Classification of Disease, Ninth Revision, Clinical Modification, we divided TKA patients into 4 subgroups: those diagnosed with depression, those diagnosed with anxiety, those concomitantly diagnosed with both depression and anxiety, and those without depression or anxiety. The chi-squared test and analysis of variance were performed to measure differences among these 4 subgroups. Multiple logistic regression analysis was used to determine whether psychological comorbidities were independent risk factors for postoperative complications and surgery-related pain. RESULTS: A total of 7,153,750 patients in the United States were estimated to have undergone TKA between 2002 and 2014. The prevalence of depression, anxiety, or both diagnoses in TKA patients significantly increased over time. Patients with psychiatric disorders showed higher hospital costs but shorter periods of hospitalization, with higher odds ratios for most complications and all pain-related symptoms observed in this study. CONCLUSION: The prevalence of depression and anxiety in TKA patients is increasing steadily each year. Psychiatric disorders were closely correlated with the outcomes of TKA. The mental health of patients undergoing TKA needs more attention to ensure adequate relief from postoperative pain-related symptoms as well as quality of life.

An evidence-based etiology study of synovial cyst of knee cruciate ligament: a real or pseudo-cyst.

PURPOSE: Synovial cyst of knee cruciate ligament (SCKCL) is a rare condition but can cause severe knee pain. The understanding of its etiology is relatively poor. This current study aimed to elucidate the pathogenesis of SCKCL based on a series of histo- and cytopathological examination. METHODS: Ten SCKCL patients who underwent arthroscopy were enrolled, among five patients claimed past knee injury. Hematoxylin & eosin staining was conducted to the cyst wall tissue sections and Papanicolaou staining to the cyst fluid smear. Prussian blue staining was employed to both the wall section and fluid smear. Immumohistochemical staining for mesothelial cells (MC), epithelial cells (CK), vascular endothelial cells (CD31), monocytes (CD68), and hematogenous stem cells (CD117) were taken to elucidate the possible involvement of various cell types in the development of SCKCL. RESULTS: No erythrocyte was discovered in the fluid; however, Prussian blue stained hemosiderin particles were found in the cyst wall and fluid, suggesting past hemorrhage in all patients. Abundant lymphocytes and plasmocytes were observed in the cyst wall and fluid. In addition, the cyst lining was infiltrated with abundant CD68(+) monocytes while only few MC(+) mesothelial cells were sporadically observed in four samples. The cyst submucosa was also diffused with abundant CD68(+) monocytes and proliferated capillaries stained with CD31. CD117-positve hematogenous stem cells were sporadically observed in eight specimens. CONCLUSION: Our findings provided evidence that SCKCL is not a mature synovial cyst but rather an inflammatory pseudo-cyst. It may have resulted from past minor hemorrhage and intra-ligament chronic inflammation.