Equal rates of bone healing and reduced surgical time with iliac crest allograft compared to autograft in medial opening wedge high tibial osteotomy: a randomized controlled clinical trial.

INTRODUCTION: Iliac crest autograft is frequently used to fill in bone defects after osteotomies. Nonetheless, surgery for bone autograft procurement is associated with morbidity and pain at the donor site. Alternatives to it have been explored, but there is no consensus to guide their application as a routine practice in several orthopedic procedures. Thus, this study was designed to compare the efficacy and safety between iliac crest autograft and allograft in medial opening wedge high tibial osteotomy. MATERIALS AND METHODS: Forty-seven patients with a symptomatic unilateral genu varum and an indication for high tibial osteotomy were randomly assigned to receive either autograft or allograft to fill the osteotomy site. Operative time, bone healing, and complication rates (delayed union, nonunion, superficial and deep infection, loss of correction, and hardware failure) were recorded after a one-year follow-up. Data were expressed as Mean ± Standard Deviation and considered statistically significant when p < 0.05. RESULTS: The time to radiologic union was similar between both groups (Allograft: 2.38 ± 0.97 months vs. Autograft: 2.45 ± 0.91 months; p = 0.79). Complication rates were also similar in both groups, with one infection in the allograft group and two in the autograft group, two delayed unions in the allograft group, and three in the autograft group. The operative time differed by 11 min between the groups, being lower in the allograft group (Allograft: 65.4 ± 15.1 min vs. Autograft: 76.3 ± 15.2 min; p = 0.02). CONCLUSION: Iliac crest allografts can be safely and effectively used in medial opening wedge high tibial osteotomy as it promotes the same rates of bone union as those achieved by autologous grafts, with the benefits of a shorter operative time. TRIAL REGISTRATION NUMBER: U1111-1280-0637 1 December 2022, retrospectively registered.

Influence of type I collagen polymorphisms and risk of anterior cruciate ligament rupture in athletes: a case-control study.

BACKGROUND: Anterior cruciate ligament (ACL) rupture is a common and severe knee injury in sports and occurs mostly due to noncontact injuries. There is an increasing amount of evidence associating ACL rupture to single nucleotide polymorphisms (SNPs), and SNPs in the collagen type I genes can change its expression and tissue mechanical features. This study aimed to investigate the association between SNPs in COL1A1 and COL1A2 with sports-related ACL tears. METHODS: A total of 338 athletes from multiple sports modalities were analyzed: 146 were diagnosed with ACL rupture or underwent an ACL reconstruction surgery and 192 have no musculoskeletal injuries. SNPs were genotyped using validated TaqMan assays. The association of the polymorphisms with ACL rupture was evaluated by a multivariable logistic regression model, using odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The age, sport modality, and training location were associated with an increased risk of a non-contact ACL tear. COL1A2 SNPs (rs42524 CC and rs2621215 GG) were associated with an increased risk of non-contact ACL injury (6 and 4-fold, respectively). However, no significant differences were detected in the distribution of COL1A1 rs1107946 and COL1A2 rs412777 SNPs between cases and controls. There was a protective association with ACL rupture (OR = 0.25; 95% CI = 0.07-0.96) between COL1A1 rs1107946 (GT or TT) and the wildtype genotypes of the three COL1A2 (rs412777, rs42524, rs2621215). COL1A2 rs42524 and rs2621215 SNPs were associated with non-contact ACL risk. CONCLUSION: The combined analysis of COL1A1-COL1A2 genotypes suggests a gene-gene interaction in ACL rupture susceptibility.

Modified Pulvertaft on Weave Technique Restores Full Active Knee Extension in Patients With Large Chronic Quadriceps Tendon Rupture: A Case Series.

PURPOSE: We aimed to investigate the clinical and functional outcomes, including maximal and explosive strength, after chronic quadriceps tendon rupture repair with Modified Pulvertaft on Weave (MPW) technique METHODS: Knee joint range of motion (ROM), patella height, thigh circumference, and Lysholm and International Knee Documentation Committee (IKDC) scores were assessed preoperatively and postoperatively. The knee extensors maximal (isokinetic peak torque and isometric maximal voluntary contraction (MVC) torque) and explosive strength-rate of torque development (RTD) early [RTD50 and RTD100] and late [RTD250]-were performed. We assessed the thigh circumference and vastus lateralis muscle thickness (MT) as indicators of quadriceps muscle mass, and the voluntary quadriceps activation using surface electromyography (EMG50). RESULTS: Nine patients (mean age: 53 ± 11 years) took part in the study. We observed a significant increase in the knee active ROM and a decreased extension deficit (both, P < .001), but not for pain (P = .07), IKDC (P = .07), and Lysholm (P = .21) after the surgery. We did not observe a difference between involved (n = 8) and uninvolved (n = 10) limbs for ROM, thigh circumference, and MT. We observed differences for extensors peak torque, MVC torque, and late RTD (all, P < .05). However, we did not observe differences for early RTD and EMG50. Significant positive correlations were observed for RTD50 (ρ = .80) and RTD100 (ρ = .81) vs EMG50. Both the IKDC and Lysholm were better correlated with the early than with later RTD. CONCLUSIONS: The MPW reestablished the active knee extension. The same level of quadriceps muscle mass was observed in both limbs, suggesting a lack of hypotrophy due to the injury. Although the involved limb had demonstrated lower knee extensors maximal strength, they demonstrate an equivalent early RTD when compared to the uninvolved limb. The early RTD seems to be better correlated with the patient's functionality than the later RTD and maximal strength. LEVEL OF EVIDENCE: IV, case series.

Approaches to preserve human osteochondral allografts.

Osteochondral defects may progress to osteoarthritis. Many attempts have been developed to overcome this issue, including osteochondral autografts and allografts. The goal of this study was to develop a new protocol for storage of human osteochondral allografts. Osteochondral plugs were randomly allocated in the following groups: control, immediate freezing up to -70 °C, cooling at 4 °C, and storage at 37 °C. Samples from the cooling at 4 °C and storage at 37 °C groups were stored in tubes containing medium plus human albumin and analyzed after 1, 3, and 14 days. The frozen groups' samples were cryopreserved for 1 year in cryotubes containing medium only (FM), medium plus human albumin (FA), and medium plus human albumin and glucose (FG) and were then analyzed. Analysis involved histological study with hematoxylin-eosin and Safranin O and a modified Live/Dead assay. In samples stored both at 37 and 4 °C, analysis showed statistically significant higher cellular mortality at 14 days compared to 1 and 3 days, but mortality in the 4 °C group was lower. In the freezing protocols, the FA group showed less cellular mortality than the FM and FG groups. Cooling at 4 °C offers better preservation capacity than storage at 37 °C, but both offer the capacity for preservation for 14 days. Adding human albumin to the storage medium is useful in reducing cellular mortality in samples frozen for 1 year.

New strategy to control cell migration and metastasis regulated by CCN2/CTGF.

Connective tissue growth factor (CTGF)/CCN family member 2 (CCN2) is a CCN family member of matricellular signaling modulators. It has been shown that CCN2/CTGF mediates cell adhesion, aggregation and migration in a large variety of cell types, including vascular endothelial cells, fibroblasts, epithelial cells, aortic smooth muscle and also pluripotent stem cells. Others matricellular proteins are capable of interacting with CCN2/CTGF to mediate its function. Cell migration is a key feature for tumor cell invasion and metastasis. CCN2/CTGF seems to be a prognostic marker for cancer. In addition, here we intend to discuss recent discoveries and a new strategy to develop therapies against CCN2/CTGF, in order to treat cancer metastasis.

Arthroscopy With Adipose-Derived Stromal Vascular Fraction Using a Selective Tissue Engineering Photo-Stimulation Technique for the Treatment of Mild to Moderate Knee Osteoarthritis.

Osteoarthritis (OA) is characterized by articular cartilage degeneration, synovial inflammation, and subchondral bone thickening, affecting the synovial joint as an organ and leading to pain and disability. Subcutaneous stromal vascular fraction is safe and relieves pain, improves function, and repairs cartilage defects in patients with knee OA. Our goal is to describe step-by-step the arthroscopic treatment of mild to moderate knee OA with photo-stimulated stromal vascular fraction harvested from the thigh using a selective tissue engineering photo-stimulation ("One S.T.E.P.") technique.

The optimized tourniquet versus no tourniquet in total knee arthroplasty. Analysis of muscle injury, functional recovery, and knee strength.

Background: Tourniquet is widely used in total knee replacement surgery because it reduces intraoperative hemorrhage and provides a comfortable surgical area for the surgeon. It's possible that its use could lead to impaired postoperative functional and motor recovery, as well as local and systemic complications. Our goal was to compare the outcomes of total knee replacement without ischemia using an optimized protocol, consisting of tourniquet inflation before skin incision and deflation after cementing, with a pressure of one hundred millimeters above systolic blood pressure and without postoperative articular suction drains.). We believed that tourniquet effectively would result in no additional muscle damage and no functional or knee strength impairment compared to no tourniquet. Methods: In a prospective and randomized study, 60 patients with osteoarthritis were evaluated for total knee replacement, divided in two groups: 'without tourniquet' and 'optimized tourniquet'. Outcomes were mean creatine phosphokinase levels, Knee Society Score and knee isokinetic strength. Data were considered significant when p < 0.05. Results: Creatine phosphokinase levels and functional score were similar between groups. There were no differences between groups regarding knee extension strength on the operated limbs, although the knee flexors' peak torque in the operated limb in the optimized tourniquet group was significantly higher at 6 months relative to preoperative and 3 months assessments. Conclusions: The optimized tourniquet protocol use in total knee replacement combines the benefits of tourniquet use without compromising functional recovery and without additional muscle damage and strength deficits compared to surgery without its use.

Predictive and protective factors for allogenic blood transfusion in total knee arthroplasty. A retrospective cohort study.

Background: This study aimed to identify the predictive and protective factors of blood transfusion in patients undergoing total knee arthroplasty (TKA) and therefore determine the profile of patients with low and high risk of blood transfusion after arthroplasty. Methods: We conducted a retrospective study with all patients who underwent primary TKA between January 2017 and December 2019 (n = 1.028 patients) in our institution. Information about allogenic transfusion was collected from medical records to determine the incidence, the predictive and protective factors of blood transfusion. All cases of blood transfusions were documented as well the number of units and the moment of each transfusion. We performed univariate and multivariate logistic regression analyses to identify the independent risk and protective factors. Results: The total transfusion rate was 11%, 1.1% at intraoperative and 9,9% at postoperative period. The independent risk factors for transfusion were female gender (OR 1.64), older age (>55yo, OR > 2) higher surgical risk (ASA III, OR 3.07), lower preoperative hemoglobin levels (p = 0.024), post-traumatic arthritis (OR 4.11) and use of postoperative drains (OR 1.81) The protective factors for transfusion were male gender (OR 0.60), obesity (IMC >30, OR 0.60) and use of intravenous tranexamic acid intraoperatively (OR 0.40). Conclusions: We conclude that in addition to the well-established risk factors for blood transfusion such as advanced age, low hemoglobin levels and high surgical risk, we can add post-fracture arthroplasty, non-use of tranexamic acid and the use of postoperative joint drain.

Treatment of Distal Patellar Tendon Chronic Rupture: The X-Wave Technique.

Injuries to the patellar tendon (PT) are associated with knee function deterioration and loss of the capacity to perform daily and sports activities. Patellar tendon injury is often misdiagnosed at emergency rooms, leading to chronic proximal retraction and a challenging clinical scenario. Proximal PT injuries are more common, while distal ones, which can involve tibial bone avulsion fractures or direct tendon avulsion, are rarer. The low incidence of distal PT rupture and the variety of injury patterns make a personal approach reasonable when based on the intraoperative findings and the surgeon's experience. Our purpose is to describe a surgical technique to restore the knee extensor mechanism after chronic distal PT rupture using two kinds of graft, one as a waveform augmentation of the native tendon and the other as reinforcement in a letter X aspect.

Posterior Root Repair of Medial Meniscus Combined With Valgus Opening Wedge Tibial Osteotomy.

The medial meniscal root tear, a particular meniscal injury at the level of its posterior bone insertion, leads to a loss of impact absorption and load distribution capacity, similar to total meniscectomy. Therefore, its repair is fundamental for knee joint longevity. This type of injury often occurs in middle-aged patients with lower limbs varus malalignment, which results in mechanical overloading of the medial compartment and induces premature cartilage wear out. The success of meniscal root repair, with meniscal bone reinsertion, depends on the correction and realignment of varus deformities greater than 5° for physiological levels. In this situation, corrective tibial osteotomy combined with meniscal repair is indicated. Our goal is to describe the step-by-step technique of the valgus opening wedge tibial osteotomy combined with the arthroscopic reinsertion of the posterior meniscal root in tibia during the treatment of a patient with varus deformity and medial meniscus root tear.

Continuous Meniscal Suture in Radial Meniscal Tear: The Hourglass Technique.

The key to preventing early knee osteoarthritis is meniscal preservation. The main functions of the meniscus are impact absorption, mechanical load transmission, lubrication, joint stability, and proprioception. Radial lesions that extend to the joint capsule are called complete radial tears. This type of injury compromises 2 of the main meniscal functions, which are impact absorption and load distribution, which is equivalent, from a biomechanical perspective, to a total meniscectomy. In the recent past, the treatment of choice for this type of injury was partial meniscectomy. However, several studies have observed progressive joint degeneration after this type of treatment. Recently, different types of meniscal sutures involving radial lesions of the meniscus have been developed. It is believed that such repairs may bring a decrease in future osteoarthritis in this patient profile. The purpose of this article is to describe the steps of continuous meniscal suture for the treatment of radial tears of the medial and lateral menisci.

How to Create an Arthroscopy Training Laboratory Using a Bovine Knee Model.

Orthopaedic surgeries by video arthroscopy have become increasingly popular, as they allow joint treatment through small incisions and minimal tissue damage. However, their execution requires specific skills from the surgeon, different from open surgery, which can only be achieved through practical training. These skills would be ideally performed on human cadaveric anatomical pieces which, however, can be difficult to access for different reasons. Animal anatomical models for surgical skills training have been used for years in medicine, and we observed that the bovine knee has anatomical characteristics quite similar to that of the human knee. In this study, we explain, step by step, the installation and creation of an arthroscopy laboratory with a bovine model, in an effort to contribute to several training centers in arthroscopic surgery around the world, assisting and guiding such centers to install arthroscopy laboratories and facilitating the improvement of more surgeons.

Protocol for Harvest, Transport and Storage of Human Osteochondral Tissue.

Objective To elaborate a protocol for the harvest, transport, and preservation of human osteochondral tissue for use in tissue banks (TBs). Methods Osteochondral fragments measuring 2 cm 3 of 5 corpse donors aged between 15 and 45 years old were analyzed. The samples were stored in cell preservation medium containing: human albumin, Iscove's and vancomycin preserved at 4°C. The concentration of proteoglycans in the extracellular medium was quantified by the use of Safranin-O, while tissue structural analysis was assessed by histological study with hematoxylin-eosin stained slides. The images obtained were analyzed according to the histological scores of Mankin and the score proposed by the OsteoArthritis Research Society International. The samples were analyzed with 0, 15, 30 and 45 days of preservation. Results The osteochondral fragments studied showed a progressive decrease in proteoglycan concentration with increased preservation time. After 30 days of preservation, structural changes were identified with discontinuity of the cartilage surface layer. According to the results obtained by the Mankin score, there was a statistically significant difference between 15 and 30 days of tissue preservation. Conclusion The protocol described defined knee transport immersed in Lactated Ringer at a controlled temperature of 10° C until its arrival at the TB. After processing, the preservation solution was composed of Iscove's serum-free cell culture medium supplemented with 10% human albumin and 100 µg/ml vancomycin. The tissue was preserved at a temperature of 4°C until the moment of transplantation characterizing the fresh preservation.

HIGHER RISK OF COMPLICATIONS AFTER TOTAL KNEE ARTHROPLASTY IN OCTOGENARIANS.

OBJECTIVE: To evaluate the complication rate of total knee arthroplasty (TKA) in octogenarian patients and identify predictive factors. METHODS: The study comprised 70 octogenarians and 70 non-octogenarian patients as control group, all submitted to TKA. We analyzed the medical records of these patients, seeking for complications during the first postoperative year. Regarding the risk factors, we evaluated: age, sex, race, American Society of Anesthesiologists score, body mass index, smoking, hypertension and diabetes mellitus. RESULTS: In the control group, the incidence of complications was 7.1%. Whereas in the octogenarian group it was significantly higher, reaching 34.3% (OR 6.8; 95% CI 2.4-19.1). We found no association to sex, skin color, and comorbidities. Age is an independent risk factor for postoperative complications. Our data may help patients to acknowledge the risks of undergoing primary TKA and physicians to assess and adjust perioperative risk. CONCLUSION: The incidence of postoperative complications is significantly higher in octogenarians. Level of Evidence III, Case-control study.

OBJETIVO: O objetivo do estudo foi avaliar a taxa de complicações da artroplastia total do joelho (ATJ) em pacientes octogenários e tentar identificar fatores preditivos. MÉTODOS: Foi realizado um estudo envolvendo 140 pacientes, divididos em dois grupos (70 octogenários e 70 com idade abaixo de 80 anos), submetidos a ATJ no período de janeiro de 2014 a agosto de 2016. Os prontuários desses pacientes foram analisados buscando a presença de complicações ocorridas no prazo de um ano após a cirurgia. Em relação aos fatores de risco foram avaliados idade, sexo, raça, American Society of Anesthesiologists, Indice de Massa Corpórea, tabagismo, hipertensão arterial e diabetes. RESULTADOS: No grupo-controle, a incidência de complicações foi de 7,1%. Já no grupo estudado foi significativamente maior, chegando a 34,3%. A razão de chances para complicações é 6,8, com intervalo de confiança ao nível de 95% igual a (2,4;19,1). A idade maior ou igual a 80 constitui, assim, fator de risco aumentado para a incidência de complicações pós-artroplastia total de joelho. CONCLUSÃO: A ocorrência de complicações após ATJ é significativamente maior no grupo dos octogenários. Nível de Evidência III, Estudo de caso-controle.

Continuous Meniscal Suture Technique of the Knee.

The menisci are fibroelastic structures interposed between the articular surfaces of the femur and tibia. They absorb impact and transmit load. Meniscal injury may compromise function and cause rapid joint degeneration, leading to the development of secondary osteoarthritis. Surgical treatment of meniscal injury is usually performed by arthroscopy, and meniscectomy or meniscal suture may be associated with such treatment. Meniscal suture should be considered when the injury compromises the proper functioning of the meniscus to recover its anatomy and function. Different meniscal suture techniques exist; the most widely used are the inside-out, outside-in, and all-inside techniques. The gold-standard repair technique is the inside-out technique. A drawback of this technique is the need to alternate between intra- and extra-articular structures for every stitch, which makes it even more laborious. We describe the continuous meniscal suture technique, also called "meniscal stitching," for a medial meniscal bucket-handle injury. This technique is performed from the inside out and allows the surgeon to perform multiple stitches with the same thread quickly and effectively. This surgical technique is performed using a single meniscal suture device that was developed by our group, called the "Meniscus 4 A-II" device.

Intraoperative morphometric study of distal femur in Brazilian patients undergoing total knee arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) is the treatment option for patients with severe osteoarthritis (OA) of the knee whose symptoms are refractory to conservative management. Unfortunately, the level of patient dissatisfaction is high, reaching up to 25%. The reasons for this dissatisfaction are multifactorial, but bone-implant mismatch significantly increases the chance of pain and functional limitation. Sex-specific prosthesis designs have been developed to overcome this issue, but their use is still controversial. The primary objective of this study was to evaluate possible sex differences in the shape of the distal femur in patients with osteoarthritis. Secondary objectives were to investigate interpersonal variability of the distal femur and to determine the number of femoral implant sizes required to meet shape variations. METHODS AND FINDINGS: A cross-sectional observational study prospectively compared 294 knees of 293 patients with osteoarthritis according to sex (201 female/93 male). Six intraoperative measurements were performed on the distal femur (height and width of both lateral and medial condyles, total medial-lateral width of the femur, and intercondylar distance). Sex differences and interpersonal variability were analyzed by multiple linear regressions. Measurements were also correlated with patient height. An optimization analysis was used to estimate the number of femoral implant sizes required. There were significant sex differences in the distal femur, where men had higher values than women in all measurements. Great interpersonal variability was found. The height of the lateral condyle was correlated with patient height, but the correlation was not strong. Twenty-five femoral implant sizes were required to meet the shape variations in our sample. CONCLUSIONS: The shape of the distal femur in patients with osteoarthritis shows great interpersonal variability, with men showing significantly higher values than women. A total of 25 different implant sizes would be necessary to adequately meet the variations observed in our study population.

Prospective Study on the Impact of the Use of Human Fibrin Sealant free of Clot-Stabilizing Agents in Total Knee Arthroplasty.

Objective The present study aimed to evaluate the results of the intraoperative topical use of a human fibrin sealant free of clot-stabilizing agents in total knee arthroplasties (TKAs), looking for differences between groups regarding blood loss, transfusion requirement, length of hospital stay, pain perception, range of motion (ROM), and incidence of complications. Methods We have analyzed prospectively an intervention group with 32 patients (Sealant) and a control group with 31 patients (Control) with symptomatic knee osteoarthritis who underwent TKA. Results The results were similar between the groups regarding visible blood loss in the drain in 24 hours (Control, 276.5 mL ± 46.24 versus Sealant, 365.9 mL ± 45.73), total blood loss in 24 hours (Control, 930 mL ± 78 versus Sealant, 890 mL ± 67) and in 60 hours after surgery (Control, 1,250 mL ± 120 versus Sealant, 1,190 mL ± 96), blood transfusion requirement (which occurred only in 1 control patient), length of hospital days stay (Control, 5.61 ± 0.50 versus Sealant, 4.81 ± 0.36), postoperative pain, and ROM. Sealant use was not related to wound healing complications, to infection, or to deep venous thrombosis. Conclusion We have concluded that the hemostatic agent composed of human fibrin was not effective in reducing bleeding volume and blood transfusion requirement, nor it interfered with hospital length of stay, pain perception, and ROM. Its use was not related to any complications.

Modified Lemaire Lateral Tenodesis Associated With an Intra-articular Reconstruction Technique With Bone-Tendon-Bone Graft Using an Adjustable Fixation Mechanism.

The goal of this study was to report a surgical technique used in a revision anterior cruciate ligament (ACL) reconstruction case, consisting of an adaptation of the anterolateral iliotibial band tenodesis technique (modified Lemaire technique) combined with ACL reconstruction using an adjustable fixation mechanism. Rotational overload was one of the most likely hypotheses for failure of primary surgery, despite correct positioning and secure fixation. We performed a review of the most pertinent factors related to ACL reconstruction failure, as well as surgical strategies for its treatment. After this, we described, step by step, a combination of the 2 forms of surgical intervention that were already presented isolated with good clinical results, correcting the common anterior and rotational instabilities found in these cases. Knowing new techniques for intra- and extra-articular ligament reconstruction is imperative in the present day, when more patients are seeking a full return to their preinjury recreational, labor, and sports activities. We believe that the combination of these surgical techniques is able to achieve these goals effectively and reproducibly.

Viscosupplementation improves pain, function and muscle strength, but not proprioception, in patients with knee osteoarthritis: a prospective randomized trial.

OBJECTIVES: This study aimed to evaluate the clinical outcomes of intra-articular infiltration with hyaluronic acid and dexamethasone alone and in combination in the treatment of knee osteoarthritis (OA). METHOD: This prospective randomized trial evaluated 44 patients undergoing treatment for OA. Patients were selected through clinical and radiological analysis using the American College of Rheumatology criteria. We included patients aged between 50 and 70 years who presented with K-L stage ≤2 knee OA and normal limb alignment. Patients with a previous history of knee injury (ligamentous, meniscal or traumatic), infection, patellofemoral OA or chondroprotective drug use in the previous year were excluded. Participants were randomized into 3 groups and underwent treatment with viscosupplementation (VS, n=16), viscosupplementation plus dexamethasone (VD, n=16) or dexamethasone (DX, n=12). All patients were evaluated before and 6 weeks, 3 months and 6 months after infiltration. Analysis included a physical examination, the Western Ontario and McMaster Universities Arthritis Index (WOMAC) questionnaire (total score and domain subscores) and an evaluation of knee extensor and flexor strength and proprioception using an isokinetic dynamometer. RESULTS: VS significantly improved the WOMAC total score and subscores for pain, stiffness and function for up to 6 months after infiltration. It also improved knee extensor and flexor strength during the same period. Proprioception was not affected by any of the treatments. CONCLUSIONS: VS alone improved pain, stiffness and function according to the WOMAC total score and subscores and improved knee extensor and flexor strength, but not proprioception, for up to six months after infiltration. These findings suggest that VS has a positive effect on quadriceps arthrogenic inhibition.

Osteoarthritic Synovial Fluid Modulates Cell Phenotype and Metabolic Behavior In Vitro.

Synovial fluid holds a population of mesenchymal stem cells (MSC) that could be used for clinical treatment. Our goal was to characterize the inflammatory and metabolomic profile of the synovial fluid from osteoarthritic patients and to identify its modulatory effect on synovial fluid cells. Synovial fluid was collected from non-OA and OA patients, which was centrifuged to isolate cells. Cells were cultured for 21 days, characterized with specific markers for MSC, and exposed to a specific cocktail to induce chondrogenic, osteogenic, and adipogenic differentiation. Then, we performed a MTT assay exposing SF cells from non-OA and OA patients to a medium containing non-OA and OA synovial fluid. Synovial fluid from non-OA and OA patients was submitted to ELISA to evaluate BMP-2, BMP-4, IL-6, IL-10, TNF-α, and TGF-ß1 concentrations and to a metabolomic evaluation using 1H-NMR. Synovial fluid cells presented spindle-shaped morphology in vitro. Samples from OA patients formed a higher number of colonies than the ones from non-OA patients. After 21 days, the colony-forming cells from OA patients differentiated into the three mesenchymal cell lineages, under the appropriated induction protocols. Synovial fluid cells increased its metabolic activity after being exposed to the OA synovial fluid. ELISA assay showed that OA synovial fluid samples presented higher concentration of IL-10 and TGF-ß1 than the non-OA, while the NMR showed that OA synovial fluid presents higher concentrations of glucose and glycerol. In conclusion, SFC activity is modulated by OA synovial fluid, which presents higher concentration of IL-10, TGF-ß, glycerol, and glucose.