Long-term efficacy of autologous bone marrow mesenchymal stromal cells for treatment of knee osteoarthritis.

Knee osteoarthritis is the most prevalent joint disease and a frequent cause of pain, functional loss and disability. Conventional treatments have demonstrated only modest clinical benefits whereas cell-based therapies have shown encouraging results, but important details, such as dose needed, long-term evolution or number of applications required are scarcely known. Here we have reanalyzed results from two recent pilot trials with autologous bone marrow-derived mesenchymal stromal cells using the Huskisson plot to enhance quantification of efficacy and comparability. We find that cell doses of 10, 40 and 100 million autologous cells per knee provided quite similar healing results and that much of the effect attained 1 year after cell application remained after 2 and 4 years. These results are encouraging because they indicate that, apart from safety and simplicity: (i) the beneficial effect is both significant and sizeable, (ii) it can be achieved with a single injection of cells, and (iii) the effect is perdurable for years.Trial registration: EudraCT 2009-017405-11; NCT02123368. Registered 25 April 2014-Prospectively registered, https://clinicaltrials.gov/ct2/show/NCT02123368?term=02123368&draw=2&rank=1.

Phase II multicenter randomized controlled clinical trial on the efficacy of intra-articular injection of autologous bone marrow mesenchymal stem cells with platelet rich plasma for the treatment of knee osteoarthritis.

BACKGROUND: Mesenchymal stromal cells are a safe and promising option to treat knee osteoarthritis as previously demonstrated in different clinical trials. However, their efficacy, optimal dose and addition of adjuvants must be determined. Here, we evaluated the clinical effects of a dose of 100 × 106 bone marrow mesenchymal stromal cells (BM-MSCs) in combination with Platelet Rich Plasma (PRGF®) as adjuvant in a randomized clinical trial. METHODS: A phase II, multicenter, randomized clinical trial with active control was conducted. Sixty patients diagnosed with knee OA were randomly assigned to 3 weekly doses of PRGF® or intraarticular administration of 100 × 106 cultured autologous BM-MSCs plus PRGF®. Patients were followed up for 12 months, and pain and function were assessed using VAS and WOMAC and by measuring the knee range of motion range. X-ray and magnetic resonance imaging analyses were performed to analyze joint damage. RESULTS: No adverse effects were reported after BM-MSC administration or during follow-up. According to VAS, the mean value (SD) for PRGF® and BM-MSC with PRGF® went from 5 (1.8) to 4.5 (2.2) (p = 0.389) and from 5.3 (1.9) to 3.5 (2.5) (p = 0.01), respectively at 12 months. In WOMAC, the mean (SD) baseline and 12-month overall WOMAC scores in patients treated with PRGF® was 31.9 (16.2) and 22.3 (15.8) respectively (p = 0.002) while that for patients treated with BM-MSC plus PRGF® was 33.4 (18.7) and 23.0 (16.6) (p = 0.053). Although statistical significances between groups have been not detected, only patients being treated with BM-MSC plus PRGF® could be considered as a OA treatment responders following OARSI criteria. X-ray and MRI (WORMS protocol) revealed no changes in knee joint space width or joint damage. CONCLUSIONS: Treatment with BM-MSC associated with PRGF® was shown to be a viable therapeutic option for osteoarthritis of the knee, with clinical improvement at the end of follow-up. Further phase III clinical trials would be necessary to confirm the efficacy. Trial registration Clinical Trials.gov identifier NCT02365142. Nº EudraCT: 2011-006036-23.

Oldest old hip fracture patients: centenarians as the lowest complexity patients.

BACKGROUND: Hip fracture leads to an increase in mortality and deterioration in the quality of life. The increase in life expectancy results in an increase in the number of oldest old patients. AIMS: To analyze the characteristics of centenarian hip fracture patients and compare them with younger hip fracture patients. METHODS: Retrospective study, including 176 patients (48 centenarians, 65 nonagenarians and 63 octogenarians) undergoing surgery after hip from 2009 to 2018 and followed for 1-year survival. Qualitative variables were compared by Chi-square test and quantitative variables, by Kruskal-Wallis test. Survival analysis was performed by Kaplan-Meier test and statistical differences were assessed by log-rank test. p value < 0.05 was considered statistically significant. RESULTS: Centenarians showed the lowest Charlson index (p = 0.001), cognitive impairment (p < 0.001), and daily drug intake (p = 0.034). The in-hospital, 30-day and 1-year mortality rates did not show statistical significant differences. The 1-year survival analysis showed that patients died in order of age (p = 0.045). No differences were found regarding readmissions. DISCUSSION: Hip fracture incidence in centenarians is increasing. Our study states the lowest complexity for centenarians. Hip fracture mortality rates have been linked to patients' age. In-hospital mortality rate has been reduced, and for the 30-day and 1-year mortality rates, we noted that mortality follows a pattern clearly related to age. CONCLUSIONS: Centenarians showed the lowest comorbidity and complexity. Readmissions before 1 year, mortality rates at discharge, 30-day and 1-year follow-up were not significantly different, but 1-year survival analysis showed that patients are dying as they are ageing.

Risk factors for periprosthetic joint infection after total knee arthroplasty.

INTRODUCTION: Periprosthetic joint infection (PJI) is the most serious and feared complication in total knee arthroplasty (TKA) and can have catastrophic consequences. The number of total knee arthroplasties is increasing, so infections could also be greater in the future. The aim of this study is to identify the most relevant risk factors associated with infection after a total knee arthroplasty. METHODS: This is a case-control study of patients who underwent total knee arthroplasty at the University Hospital of Salamanca. We included 66 TKA PJI patients and 66 control TKA patients. Demographic and clinical variables were collected. A descriptive and inferential analysis was performed by logistic regression and attributable risk fraction assessed. RESULTS: Prolonged operative time (> 90') and tourniquet time (> 60') were the most relevant risk factors described (OR 40.77, AFE 0.97, p > 0.001 and OR 37.14, AFE 0.97, p < 0.001, respectively). The use of non-antibiotic-laded cement (OR 3.62), obesity (BMI > 30, OR 8.86), diabetes (OR 2.33), high ASA grade (III-IV, OR 15.30), and blood transfusion requirement (OR 4.60) were also statistically significant risk factors for TKA PJI. CONCLUSIONS: Our study provides evidence concerning that operative time, tourniquet time, cement type, diabetes, obesity, ASA grade, and blood transfusion requirement as independently associated risk factors for TKA PJI. Modifiable risk factors were specifically relevant, so we should be able to reduce the infection rate.

Geriatric scores can predict long-term survival rate after hip fracture surgery.

BACKGROUND: The management of hip fractures is nowadays mainly performed in Orthogeriatric Units, one of whose fundamental tools is the application of geriatric scores. The purpose of this study is to establish the potential usefulness of Barthel Index, Katz Index, Lawton-Brody Index and Physical Red Cross Scale geriatric scores as predictors of survival rate and readmission rate in older patients after hip fracture surgery. METHODS: We designed a prospective single-center observational study, including 207 older adults over age 65 who underwent hip fracture surgery in the first half of 2014 and followed up to September 2018. Cumulative survival and readmission rates were analyzed by Kaplan-Meier; group comparison, by Log-Rank and hazard ratio, by Cox regression. RESULTS: We found statistical differences (p < 0.001) for cumulative survival rate by every geriatric score analyzed (BI HR = 0.98 [0.97,0.99]; KI HR = 1.24 [1.13-1.37]; LBI HR = 1.25 [1.16, 1.36]; PCRS HR = 1.67 [1.37,2.04]). Furthermore, we could determinate an inflection point for survival estimation by Barthel Index (BI 0-55/60-100*, p < 0.001, HR = 2.37 [1.59,3.53]), Katz Index (KI A-B*/C-G, p < 0.001, HR = 2.66 [1.80, 3.93], and Lawton-Brody Index (LBI 0-3/4-8*, p < 0.001, HR = 3.40 [2.09,5.25]). We reveal a correlation of the Charlson Index (p = 0.002) and Katz Index (p = 0.041) with number of readmissions for the study period. CONCLUSIONS: The geriatric scores analyzed are related to the cumulative survival rate after hip fracture surgery for more than 4 years, independently of other clinical and demographic factors. Katz Index in combination with Charlson Index could also be a potential predictor of the number of readmissions after surgery for hip fracture patients.

Intra-articular injection of two different doses of autologous bone marrow mesenchymal stem cells versus hyaluronic acid in the treatment of knee osteoarthritis: long-term follow up of a multicenter randomized controlled clinical trial (phase I/II).

BACKGROUND: Mesenchymal stromal cells (MSCs) are a promising option to treat knee osteoarthritis (OA). Their safety and usefulness have been reported in several short-term clinical trials but less information is available on the long-term effects of MSC in patients with osteoarthritis. We have evaluated patients included in our previous randomized clinical trial (CMM-ART, NCT02123368) to determine their long-term clinical effect. MATERIALS: A phase I/II multicenter randomized clinical trial with active control was conducted between 2012 and 2014. Thirty patients diagnosed with knee OA were randomly assigned to Control group, intraarticularly administered hyaluronic acid alone, or to two treatment groups, hyaluronic acid together with 10 × 106 or 100 × 106 cultured autologous bone marrow-derived MSCs (BM-MSCs), and followed up for 12 months. After a follow up of 4 years adverse effects and clinical evolution, assessed using VAS and WOMAC scorings are reported. RESULTS: No adverse effects were reported after BM-MSCs administration or during the follow-up. BM-MSCs-administered patients improved according to VAS, median value (IQR) for Control, Low-dose and High-dose groups changed from 5 (3, 7), 7 (5, 8) and 6 (4, 8) to 7 (6, 7), 2 (2, 5) and 3 (3, 4), respectively at the end of follow up (Low-dose vs Control group, p = 0.01; High-dose vs Control group, p = 0.004). Patients receiving BM-MSCs also improved clinically according to WOMAC. Control group showed an increase median value of 4 points (- 11;10) while Low-dose and High-dose groups exhibited values of - 18 (- 28;- 9) and - 10 (- 21;- 3) points, respectively (Low-dose vs Control group p = 0.043). No clinical differences between the BM-MSCs receiving groups were found. CONCLUSIONS: Single intraarticular injection of in vitro expanded autologous BM-MSCs is a safe and feasible procedure that results in long-term clinical and functional improvement of knee OA.

Intra-articular injection of two different doses of autologous bone marrow mesenchymal stem cells versus hyaluronic acid in the treatment of knee osteoarthritis: multicenter randomized controlled clinical trial (phase I/II).

BACKGROUND: Mesenchymal stromal cells are a promising option to treat knee osteoarthritis. Their safety and usefulness must be confirmed and the optimal dose established. We tested increasing doses of bone marrow mesenchymal stromal cells (BM-MSCs) in combination with hyaluronic acid in a randomized clinical trial. MATERIALS: A phase I/II multicenter randomized clinical trial with active control was conducted. Thirty patients diagnosed with knee OA were randomly assigned to intraarticularly administered hyaluronic acid alone (control), or together with 10 × 10(6) or 100 × 10(6) cultured autologous BM-MSCs, and followed up for 12 months. Pain and function were assessed using VAS and WOMAC and by measuring the knee motion range. X-ray and magnetic resonance imaging analyses were performed to analyze joint damage. RESULTS: No adverse effects were reported after BM-MSC administration or during follow-up. BM-MSC-administered patients improved according to VAS during all follow-up evaluations and median value (IQR) for control, low-dose and high-dose groups change from 5 (3, 7), 7 (5, 8) and 6 (4, 8) to 4 (3, 5), 2 (1, 3) and 2 (0,4) respectively at 12 months (low-dose vs control group p = 0.005 and high-dose vs control group p < 0.009). BM-MSC-administered patients were also superior according to WOMAC, although improvement in control and low-dose patients could not be significantly sustained beyond 6 months. On the other hand, the BM-MSC high-dose group exhibited an improvement of 16.5 (12, 19) points at 12 months (p < 0.01). Consistent with WOMAC and VAS values, motion ranges remained unaltered in the control group but improved at 12 months with BM-MSCs. X-ray revealed a reduction of the knee joint space width in the control group that was not seen in BM-MSCs high-dose group. MRI (WORMS protocol) showed that joint damage decreased only in the BM-MSC high-dose group, albeit slightly. CONCLUSIONS: The single intraarticular injection of in vitro expanded autologous BM-MSCs together with HA is a safe and feasible procedure that results in a clinical and functional improvement of knee OA, especially when 100 × 10(6) cells are administered. These results pave the way for a future phase III clinical trial. CLINICAL TRIALS: gov identifier NCT02123368. Nº EudraCT: 2009-017624-72.

Comparative analysis of the immunomodulatory capacities of human bone marrow- and adipose tissue-derived mesenchymal stromal cells from the same donor.

BACKGROUND AIMS: The immunomodulatory properties of mesenchymal stromal cells (MSCs), together with their tissue regenerative potential, make them interesting candidates for clinical application. METHODS: In the current study, we analyzed the in vitro immunomodulatory effects of MSCs derived from bone marrow (BM-MSCs) and from adipose tissue (AT-MSCs) obtained from the same donor on both innate and acquired immunity cells. BM-MSCs and AT-MSCs were expanded to fourth or fifth passage and co-cultured with T cells, monocytes or natural killer (NK) cells isolated from human peripheral blood and stimulated in vitro. The possible differing impact of MSCs obtained from distinct sources on phenotype, cell proliferation and differentiation, cytokine production and function of these immune cells was comparatively analyzed. RESULTS: BM-MSCs and AT-MSCs induced a similar decrease in NK-cell proliferation, cytokine secretion and expression of both activating receptors and cytotoxic molecules. However, only BM-MSCs significantly reduced NK-cell cytotoxic activity, although both MSC populations showed the same susceptibility to NK-cell-mediated lysis. AT-MSCs were more potent in inhibiting dendritic-cell (DC) differentiation than BM-MSC, but both MSC populations similarly reduced the ability of DCs to induce CD4(+) T-cell proliferation and cytokine production. BM-MSCs and AT-MSCs induced a similar decrease in T-cell proliferation and production of inflammatory cytokines after activation. CONCLUSIONS: AT-MSCs and BM-MSCs from the same donor had similar immunomodulatory capacity on both innate and acquired immunity cells. Thus, other variables, such as accessibility of samples or the frequency of MSCs in the tissue should be considered to select the source of MSC for cell therapy.

Immunomodulatory effects of bone marrow versus adipose tissue-derived mesenchymal stromal cells on NK cells: implications in the transplantation setting.

INTRODUCTION: The ability of mesenchymal stromal cells (MSC) to suppress T-cell function has prompted their therapeutic use for graft-versus-host disease (GVHD) control. However, as MSC also modulate the activity of NK cells, which play an important role in graft-versus-leukemia (GVL) reaction, their administration could hamper this beneficial effect of allogeneic hematopoietic stem cell transplantation. MSC can be expanded from several sources, especially bone marrow and fat, but it is not well established if the cell source makes a difference in their immunoregulatory capacity. OBJECTIVE: The aim of this study was to compare the immunomodulatory effect of MSC derived from bone marrow (BM-CSM) or adipose tissue (AT-MSC) on NK cells, to determine whether the use of MSC from one or the other origin could be more favorable to preserve NK cell activity and, therefore, GVL. METHODS: Human NK cells were stimulated with IL-15 in the presence of BM-MSC or AT-MSC. The effect of both MSC populations on NK cell proliferation, cell cycle progression, and CD56 expression was analyzed by flow cytometry. Cytokine secretion was measured by ELISA, and cytotoxic activity was assessed by calcein release assays. RESULTS: Although both BM-MSC and AT-MSC induced a similar inhibition of NK cell proliferation, only BM-MSC decreased significantly NK cell cytotoxic activity and showed a trend for a higher reduction of IFN-γ secretion. CONCLUSION: These results suggest that, in the context of GVHD inhibition, the use of AT-MSC rather than BM-MSC could further preserve NK cell activity and, thus, favor GVL.

Analysis of the immune system of multiple myeloma patients achieving long-term disease control by multidimensional flow cytometry.

Multiple myeloma remains largely incurable. However, a few patients experience more than 10 years of relapse-free survival and can be considered as operationally cured. Interestingly, long-term disease control in multiple myeloma is not restricted to patients with a complete response, since some patients revert to having a profile of monoclonal gammopathy of undetermined significance. We compared the distribution of multiple compartments of lymphocytes and dendritic cells in the bone marrow and peripheral blood of multiple myeloma patients with long-term disease control (n=28), patients with newly diagnosed monoclonal gammopathy of undetermined significance (n=23), patients with symptomatic multiple myeloma (n=23), and age-matched healthy adults (n=10). Similarly to the patients with monoclonal gammopathy of undetermined significance and symptomatic multiple myeloma, patients with long-term disease control showed an expansion of cytotoxic CD8(+) T cells and natural killer cells. However, the numbers of bone marrow T-regulatory cells were lower in patients with long-term disease control than in those with symptomatic multiple myeloma. It is noteworthy that B cells were depleted in patients with monoclonal gammopathy of undetermined significance and in those with symptomatic multiple myeloma, but recovered in both the bone marrow and peripheral blood of patients with long-term disease control, due to an increase in normal bone marrow B-cell precursors and plasma cells, as well as pre-germinal center peripheral blood B cells. The number of bone marrow dendritic cells and tissue macrophages differed significantly between patients with long-term disease control and those with symptomatic multiple myeloma, with a trend to cell count recovering in the former group of patients towards levels similar to those found in healthy adults. In summary, our results indicate that multiple myeloma patients with long-term disease control have a constellation of unique immune changes favoring both immune cytotoxicity and recovery of B-cell production and homing, suggesting improved immune surveillance.

Therapeutic potential of mesenchymal stromal/stem cells in critical-care patients with systemic inflammatory response syndrome.

BACKGROUND: Despite notable advances in the support and treatment of patients admitted to the intensive care unit (ICU), the management of those who develop a systemic inflammatory response syndrome (SIRS) still constitutes an unmet medical need. MAIN BODY: Both the initial injury (trauma, pancreatitis, infections) and the derived uncontrolled response promote a hyperinflammatory status that leads to systemic hypotension, tissue hypoperfusion and multiple organ failure. Mesenchymal stromal/stem cells (MSCs) are emerging as a potential therapy for severe ICU patients due to their potent immunomodulatory, anti-inflammatory, regenerative and systemic homeostasis-regulating properties. MSCs have demonstrated clinical benefits in several inflammatory-based diseases, but their role in SIRS needs to be further explored. CONCLUSION: In the current review, after briefly overviewing SIRS physiopathology, we explore the potential mechanisms why MSC therapy could aid in the recovery of this condition and the pre-clinical and early clinical evidence generated to date.

Lower estimated glomerular filtration rate at admission is associated with a worse outcome in older patients with hip fracture who undergo surgical treatment.

BACKGROUND: We assessed the relationship of estimated glomerular filtration rate values at hospital admission on the outcome of surgically treated older adults who had suffered a hip fracture. METHODS: Prospective study that included patients > 65 years of age, surgically treated for primary hip fracture, with no pathologic or high-energy trauma aetiology admitted to a tertiary teaching hospital between 2018 and 2019. We stratified patients based on their estimated glomerular filtration rate at admission and examined its association to demographic and clinical variables, including 90-day post-discharge mortality. RESULTS: The study included 942 hip fracture patients. Lowered estimated glomerular filtration rate was significantly associated to a worsening of the functional status, higher incidence of medical postoperative complications, higher postoperative renal dysfunction, and greater number of blood transfusions. Mortality displayed a staircase pattern, increasing with decreasing estimated glomerular filtration rate. Patients with estimated glomerular filtration rate <60 had significantly higher mortality at 90 days after discharge. In-hospital mortality rate was 10.7% in hip fracture patients with chronic kidney disease who experienced a significant variation in the estimated glomerular filtration rate (>5 mL/min/1.73m2) on admission in comparison to baseline values. CONCLUSION: Older adult patients treated for hip fracture with lower glomerular filtration rate values have poorer functional status and worse prognosis. A significant clinical variation of estimated glomerular filtration rate upon hospital admission for hip fracture may be associated with increased in-hospital mortality of chronic kidney disease patients.

Long-Term Results of a Phase I/II Clinical Trial of Autologous Mesenchymal Stem Cell Therapy for Femoral Head Osteonecrosis.

(1) Background: Osteonecrosis of the femoral head (ONFH) is characterized by impaired vascularization with ischemia resulting in bone cell death, leading to the deterioration of the hip joint. Mesenchymal stem/stromal cells (MSCs) are an attractive potential therapeutic approach in this setting. The aim of this study is to evaluate the clinical improvement in terms of pain and quality of life, as well as the safety of the procedure during the follow-up of patients. (2) Methods: A Phase I-II Open-Label Non-Randomized Prospective clinical trial was conducted. Eight patients with idiopathic ONFH and stage < IIC in the ARCO classification were included. Four weeks before therapy, 40 mL of autologous bone marrow was obtained, and MSCs were expanded under Good-Manufacturing-Practice (GMP) standards. Study medication consisted of a suspension of autologous BM-derived MSCs (suspended in a solution of 5-10 mL of saline and 5% human albumin) in a single dose of 0.5-1 × 106 cells/kg of the patient, administered intraosseously with a trocar and under radioscopic control. Per-protocol monitoring of patients included a postoperative period of 12 months, with a clinical and radiological assessment that included the visual analog scale (VAS), the Harris scale, the SF-36, and the radiological evolution of both hips. In addition, all patients were further followed up for eight years to assess the need for long-term total hip replacement (THR) surgery. (3) Results: Median age of patients included was 48.38 ± 7.38 years, and all patients were men. Autologous MSCs were expanded in all cases. There were no adverse effects related to cell administration. Regarding efficacy, both VAS and ODI scores improved after surgery. Radiologically, 12.5% of patients improved at the end of follow-up, whereas 50% improved clinically. No adverse effects related to the procedure were recorded, and none of the patients needed THR surgery within the first year after MSC therapy. (4) Conclusions: The use of autologous MSCs for patients with ONFH disease is feasible, safe in the long term, and potentially effective.

Autologous mesenchymal stem cell transplantation for spinal fusion: 10 years follow-up of a phase I/II clinical trial.

Posterolateral spinal fusion is the standard surgical approach for patients with degenerative disc disease. In our previously published article, we reported a 5-years follow-up of a phase I/II clinical trial in patients undergoing spinal fusion with autologous mesenchymal stem cells (MSCs) embedded in tricalcium phosphate. In the current manuscript, we have updated the results with a 10-year follow-up, the longest reported to date in this setting. After clinical and radiological evaluation, safety of the procedure was further confirmed in all 11 treated patients, with no evidence of tumor, infection, inflammatory reaction, or heterotopic ossification related to the administration of MSCs. Regarding clinical efficacy, low back pain and radicular pain (both assessed by the visual analogue scale-VAS), and the Owestry Disability Index remained significantly lower compared to pre-intervention. Radiologic evaluation demonstrated spinal fusion in all cases, improving over time. Finally, quality of life improved significantly also during follow-up. In summary, the use of tricalcium phosphate-embedded autologous MSCs with lumbar posterolateral arthrodesis is safe and potentially provides long-term benefits for 10 years.

[Effects mangrove conversion to pasture on density and shell size of two gastropods in the Turbo River Delta (Urabá Gulf, Caribbean coast of Colombia)]. / Efecto de la conversión del manglar a potrero sobre la densidad y tallas de dos gasterópodos en el delta del río Turbo (golfo de Urabá, Caribe colombiano).

Mangrove deforestation is widespread in the Greater Caribbean but its impact on macrobenthos has not been evaluated to date. In order to assess the impact of mangrove conversion to pasture, densities and shell sizes of two dominant gastropods (Neritina virginea and Melampus coffeus) were compared among four mangrove types: 1) Rhizophora mangle-dominated fringing mangroves, 2) Avicennia germinans-dominated basin mangroves, 3) Mixed-species basin mangroves, and 4) A. germinans- basin mangroves converted to pastures, in the Turbo River Delta (Urabá Gulf, Colombia). Mangrove types were polygon-delimited with satellite images and color aerial photographs were taken in 2009. Various (n<5) polygons per mangrove type were sampled in January, July and December 2009, and a total (n<20) 0.025m2-quadrats were randomly placed along each polygon. Forest structure variables, pore-water physicochemical variables and sediment-grain metrics were measured in the four mangrove types. Mean density and size of both gastropod species were measured. The results showed that the mean density and size of both species were significantly greater in R. mangle-fringing mangroves. N. virginea density decreased gradually towards the A. germinans-basin mangroves seemly related to the diadromous life-history. This species nearly disappeared in the neighboring pastures because individuals were constrained to a few remaining flooded areas. In the pastures, M. coffeus individuals were clumped in the remaining A. germinans trees due to its climbing behavior as a pulmonate. We hypothesize that the decline of these two gastropods was related to physical microhabitat (e.g. trees, prop roots, and seedlings) degradation, and alteration of soil properties (e.g. temperature, pH, organic matter content). Finally, we also hypothesize that the local extinction of N. virginea due to clear-cutting may exert strong negative effects on the ecosystem function because it is a dominant omnivore.

Anterior cruciate ligament innervation in primary knee osteoarthritis.

OBJECTIVE: To relate the Anterior Cruciate Ligament (ACL) innervation and histologic degeneration status to the knee osteoarthritis radiologic and functional status. DESIGN: Prospective observational study including 30 consecutive patients affected by primary knee osteoarthritis undergoing Total Knee Arthroplasty (TKA). All patients suffering secondary knee osteoarthritis, an antecedent of an infectious process, malignant process, autoimmune disorder, or previous knee surgery were excluded. We recorded biodemographic, clinical, and radiologic variables of all participants previous to the TKA procedure. ACL tissue was harvested during TKA standard procedure and the obtained sample was fixed in 4% formalin and paraffin-embedded. ACL cross-sections were stained by haematoxylin-eosin and Gallego staining for elastic and collagen fibers, and Sevier-Munger silver staining for nervous tissue. RESULTS: ACL samples histologic degeneration classification reported 15.4% normal, 23.1% slight, 26.9% mild, 11.5% moderate and 23.1% marked. We noted 46.2% large nervous fascicles, 15.4% medium fascicles, 3.8% small fascicles, and no nerve fibers were found in 34.6% ACL samples. No significant correlation was found between the histologic degeneration and the nervous fiber quantification (p>0.05, in all cases). We noted a significant histologic degeneration inverse correlation with the VAS scale (p=0.016), and nervous fiber quantification correlation with Lequesne maximum distance walked punctuation (p=0.043). We also noted greater nervous fiber quantification with minor radiological knee osteoarthritis (Kellgren-Lawrence grade II). CONCLUSIONS: ACL degeneration and innervation deficit may play a role in primary knee osteoarthritis onset, but the lack of a defining relationship among the different parameters assessed justifies further research in greater populations.

Titanium and tantalum as mesenchymal stem cell scaffolds for spinal fusion: an in vitro comparative study.

INTRODUCTION: In the last few years, great interest has been focused on tissue engineering as a potential therapeutic approach for musculoskeletal diseases. The role of metallic implants for spinal fusion has been tested in preclinical and clinical settings. Titanium and tantalum have excellent biocompatibility and mechanical properties and are being used in this situation. On the other hand, the therapeutic role of mesenchymal stem cells (MSC) is extensively explored for their multilineage differentiation into osteoblasts. OBJECTIVES: In vitro comparison of titanium and tantalum as MSCs scaffolds. MATERIAL AND METHODS: In the present study, we have compared the in vitro expansion capacity, viability, immunophenotype (both explored by flow cytometry) and multi-differentiation ability of MSC cultured in the presence of either titanium or tantalum fragments. The adherence of MSC to either metal was demonstrated by electron microscopy. RESULTS: Both metals were able to carry MSC when transferred to new culture flasks. In addition, our study shows that culture of MSC with titanium or tantalum improves cell viability and maintains all their biological properties, with no significant differences regarding the metal employed. CONCLUSION: This would support the use of these combinations for clinical purposes, especially in the spinal fusion and reconstruction setting.

Quality assessment of orthopedic surgery referral request letters from primary care consultation: Evaluation of a Spanish healthcare area.

BACKGROUND: One of the most requested referrals for specialist consultations from primary care (PC) is orthopedic surgery (OS). The purpose of this work was to analyze the number, characteristics, and quality of PC referral request letters in a Spanish healthcare area to their OS reference department. MATERIALS AND METHODS: The referral rates for 10 years were collected, and a total of 6,225 referral letters issued during the first half of 2019 were analyzed in detail. Gender, age, patient provenance, as well as priority and other process descriptors (type of pathology, suspected diagnosis, exploratory signs, imaging tests) were assessed. A scoring system was developed to evaluate the quality of the referral to an OS consultation: Quality evaluation in OS (QEOS) model. RESULTS: The rate of referral to OS is rising. The mean age of the referred patient was 53 years and 59.3% were women. Degenerative pathologies justified most referral requests (65.7%), most of which related to the spine (24.2%) or the knee (23.2%). In the QEOS analysis of the referral request letters, we noted that only 36.5% described some physical exploration, 32.9% image tool request, 25.8% indicated the pharmacological treatment, and 11.2% subsequent physiotherapy, resulting in a poor average quality of PC to OS patient referral. CONCLUSION: There is a growing demand for patient referral from PC to OS, however, the number, content, and quality of referral request letters varies greatly. The QEOS tool can be the germ of a simple evaluation system that would help in the improvement of the process of continuous care.