Female representation in orthopedic surgery: where do we stand in Belgium ?

Female underrepresentation in Orthopedic Surgery and Traumatology is a well-known issue worldwide, including in Belgium. Most of the literature comes from northern America. This two-part study aims to quantify the female workforce in orthopedic surgery in Belgium and assess the presence of unconscious biases among active orthopedic surgeons. Epidemiological data from national registries, orthopedic societies and universities in Belgium were analyzed. This included data on medical students, residents, active orthopedic surgeons and awards given by a Belgian orthopedic society. Additionally, a questionnaire was administered to Belgian orthopedic surgeons, assessing their perceptions of gender stereotypes and potential unconscious biases. 90 participants responded with 70% of men and mean age was 36 years old. The data revealed that 12% of active orthopedic surgeons in Belgium were women in 2020. However, the representation f women was higher among residents, with a thirty percent distribution. In one university, women had a slightly higher chance of getting accepted in the orthopedic training then men. The questionnaire results indicated the presence of unconscious bias regarding subspecialties, which aligned with the actual distribution. Women tend to specialize more in upper limb surgery and pediatrics while men focus more frequently on lower limb surgery. The findings highlight the need for addressing the underrepresentation of women in orthopedic surgery and traumatology in Belgium. If the current rate of progress continues, it is projected that 30% of active orthopedic surgeons will be female by the year 2074. Identifying and addressing factors contributing to the underrepresentation, such as lack of mentorship, unconscious biases, visibility issues, and discrimination, is crucial for empowering future female orthopedic surgeons and fostering diversity in the field. Collaboration among European universities and orthopedic societies can play a vital role in reducing barriers and promoting gender equality in orthopedic surgery and traumatology.

Unilateral versus simultaneous bilateral total hip arthroplasty. The Belgian experience.

Bilateral hip osteoarthritis is frequent. The safety and patient selection for simultaneous bilateral total hip arthroplasty (SBTHA) are still debated. The purpose of this article is to share our experience and assess if performing SBTHA carries more risk than unilateral total hip arthroplasty (UTHA). METHODS: A retrospective data analysis was performed on 468 patients who underwent either UTHA (418 patients) or SBTHA (50 patients) using a direct anterior approach between June 2016 and December 2020. Apart from SBTHA patients being significantly younger, there was no significant preoperative difference in demographics, comorbidities, surgical variables and biological values between the two groups. Primary outcomes were 90-days emergency room (ER) visit and readmission, as well as 90-days minor and major complications. Secondary outcomes were length of stay (LOS), operative time and blood loss. RESULTS: 90-days ER visit (p=0.244), 90- days readmission (p=0.091), overall complications rate (p=0.376), minor complications (p=0.952) and major complications (p=0.258) were not statistically different between the two groups. Operative time and average LOS were significantly longer in the SBTHA group (p<0.001). Blood loss was significantly higher (p<0.001) in the SBTHA group. However, no difference in the transfusion rate between the two groups was observed (p=0.724). CONCLUSION: Complication rate, 90- days hospital readmission and 90-days ER visit were similar between the two groups. This study shows that performing SBTHA is a safe, effective, and doesn't carry additional risks for patients with bilateral symptomatic osteoarthritis.

Are C-reactive protein (CRP) and neutrophil to lymphocyte ratio (NLR) predictive markers of successful two-stage prosthetic joint infection management?

The treatment of prosthetic joint infections (PJI) regularly involves a two-stage surgical strategy. The second stage is generally performed when the surgeon estimates that the infection is under control based on either the treatment length or clinical and biological data. We have raised the question whether standardization of C-reactive protein (CRP) and neutrophil to lymphocyte ratio (NLR) values could be either indicative of infection control or predictive of infection recurrence. This was an analytical retrospective and monocentric cross-sectional observational study. The CRP and NLR values were recorded prior to the second-stage surgery in a sample of 100 patients who underwent a two-stage revision arthroplasty following a PJI, and these values were correlated with the absence of infectious recurrence within a 2-year follow-up. The statistical analysis consisted of evaluating the diagnostic validity of each marker, first individually, and then in combination. CRP was shown associated with a 68% sensitivity, 40% specificity, 27% positive predictive value (PPV), and 79% negative predictive value (NPV). The ROC curve was 51.1%. The NLR displayed a 12% sensitivity, 89% specificity, 27% PPV, and 75% NPV. The ROC curve was 47.9%. The combination of the two markers did not fundamentally improve the statistical results, with only a 43% concordance of the two markers, 27% sensitivity, 84% specificity, 37% PPV, and 77% NPV. Measuring CRP and NLR values, either individually or in combination, before the second-stage revision arthroplasty did not turn out to be predictive of either infection recurrence or cure within two years of follow-up. Therefore, an absolute test is still lacking, which would enable us to predict without failure the absence of control or the control of a PJI before or after second-stage revision. Level of evidence: Level III, retrospective cross-sectional study.

Neutrophil-to-lymphocyte ratio (NLR) distribution shows an advantage compared to C-reactive protein (CRP) for the early inflammation monitoring after total hip arthroplasty.

C-reactive protein (CRP) distribution has been used to monitor early inflammation after total hip arthroplasty (THA). Neutrophil to lymphocyte ratio (NLR) is a new and cheap inflammatory marker. This study aimed to verify whether Neutrophil to lymphocyte ratio (NLR) distribution has an advantage when compared to C-reactive protein (CRP) distribution for the inflammation monitoring after total hip arthroplasty (THA). 116 THA patients were retrospectively selected over a 2 years period. They all had available blood tests preoperatively and at postoperative days 2, 4 and 42. Median peak values were compared between CRP and NLR. The effect of demographics on CRP and NLR was tested. At days 4 and 42, 100% and 16.3% of patients had not reached normal CRP (< 10mg/L) while 56.8% and 6.8% of patients had not reached normal NLR (<5) respectively. There was no effect of demographics on NLR except for age. Older patients had higher NLR (p 0.037). NLR showed a quicker return to normal than CRP. Our results show that NLR seems to be a better marker to follow inflammation after THA than CRP.

Bone morphotypes of the varus and valgus knee.

BACKGROUND: Coronal deformity correction with total knee arthroplasty (TKA) is an important feature in the treatment of osteoarthritis (OA). The hypothesis of this study was that bone morphology would be different in varus and valgus deformity, both before osteoarthritis development as well as during and after the disease process of OA. MATERIALS AND METHODS: Retrospective study with measurements on preoperative and postoperative full leg standing radiographs of 96 patients who underwent TKA. The included patients were selected for this study because they had an OA knee on one side and a non-arthritic knee on the contralateral side presenting the same type of alignment as the to-be-operated knee (varus or valgus alignment on both sides). The control group of 46 subjects was a group of patients with neutral mechanical alignment who presented for ligamentous problems. A single observer measured mechanical alignment, anatomical alignment, anatomical-mechanical femoral angle and intra-articular bone morphology parameters with an accuracy of 1°. RESULTS: Varus OA group has less distal femoral valgus (mLDFA 89°) than control group (87°) and valgus OA group (mLDFA 85°). Varus OA group has same varus obliquity as control group (MPTA 87°) but more than valgus OA group (MPTA 90°). Joint Line Congruency Angle (JLCA) is 3°open on lateral side in varus and medially open in valgus OA group (2°). The non-arthritic valgus group presents a constitutional mechanical valgus of 184° Hip-Knee-Ankle (HKA) angle. DISCUSSION: Varus deformity in OA as measured with an HKA angle (HKA) <177° is a combination of distal femoral wear, tibial varus obliquity and lateral joint line opening. Valgus deformity in OA with an HKA > 183° is a combination of femoral distal joint line obliquity and wear combined with medial opening due to medial collateral ligament stretching. The clinical importance of bone morphotype analysis is that it shows the intra-articular potential of alignment correction when mechanical axis cuts are performed. CONCLUSION: Bone morphology in varus and valgus deformity is different before and after osteoarthritis. Perpendicular cuts to mechanical axes do not necessarily lead to neutral mechanical axis. Constitutional mechanical valgus was observed as 184° HKA angle before the development of OA. LEVEL OF EVIDENCE: Level IV study.

Difficult to treat osteoarticulars infections : Focus on Mycobacterial and Fungal infection.

Bone and joint infections are rare but often devastating. While bacteria are most commonly encountered organisms, mycobacteria and fungi are less frequent. Management of the latter is often more complex, especially in the presence of foreign material. We will increasingly be faced with mycobacterial and fungal bone infections, as medical conditions and newer therapeutics lead to more immunosuppression. In this article, we will review osteomyelitis, septic arthritis and peri-prosthetic joint infections related to mycobacteria and fungi.

Joint awareness in osteoarthritis of the hip and knee evaluated with the 'Forgotten Joint' Score before and after joint replacement.

PURPOSE: To utilize the 'Forgotten Joint' Score (FJS), a 12-item questionnaire analysing the ability to forget the joint, for comparing preoperative status in osteoarthritic patients scheduled for total hip arthroplasty (THA) or total knee arthroplasty (TKA). Higher scores represent a better result with a maximum of 100. The hypothesis of this study was that a preoperative difference in favour of hip arthritis could eventually explain why THA is cited more often as a forgotten joint than TKA. METHODS: A prospective cohort study was conducted in 150 patients with either tricompartmental knee (n = 75) or hip osteoarthritis (n = 75). Patients completed FJS-12 scores preoperatively and 1 year postoperatively. RESULTS: A similar preoperative FJS-12 was observed for hip (22 (15)) and knee osteoarthritis (24 (17)) (n.s.). The postoperative FJS-12 score was significantly higher for THA (80 (24)) than for TKA (70 (27)) (p < 0.05). High reliability after 6 weeks was observed for the preoperative FJS-12 test-retest reliability (ICC = 0.87) in TKA. A preoperative floor effect of 15 % in THA and 0 % in TKA was found as well as a postoperative ceiling effect of 33 % in THA and 9 % in TKA. CONCLUSIONS: The clinical relevance of utilizing the FJS-12 as an instrument to evaluate outcome is strongly proposed for knee arthroplasty. In general, one is not aware of a healthy joint during the ADL, and it can therefore be regarded as 'forgotten'. The preoperative FJS-12 Score is a powerful tool to provide patients with clearer insights into their positive evolution after surgery. The use of the FJS-12 in THA is a topic for further research, as this study found that floor and ceiling effects limit its usefulness in studies evaluating clinical outcome in this area. LEVEL OF EVIDENCE: II.

Total knee arthroplasty in patients with substantial deformities using primary knee components.

PURPOSE: Although advocated for severe varus and valgus deformities, constrained implant designs are associated with a number of disadvantages in total knee arthroplasty (TKA). Combining a minimally invasive surgical approach with an interchangeable posterior stabilized (PS) implant design may allow adequate soft tissue balancing with a minimal amount of constraint and without residual instability. METHODS: Retrospectively 51 patients operated with the minimally invasive far medial subvastus approach for severe varus or valgus deformity, who underwent primary TKA with a fully interchangeable PS implant (Vanguard, Biomet Inc., Warsaw IN, USA) between 2009 and 2013 were examined. Soft tissue releases was performed using a piecrust needling technique. Preoperative alignment and surgical parameters were collected for all patients. All patients underwent preoperative and follow-up radiographic assessment and completed a battery of clinical assessments. RESULTS: All procedures were performed successfully, with alignment improving from a preoperative mean (SD) varus deformity of 165° (3°) and a mean (SD) valgus deformity of 196° (4.5°) to an overall mean (SD) postoperative mechanical alignment of 179.5° (3.0°). Nine patients had postoperative varus, while three patients had a postoperative valgus deviation from neutral alignment >3°. The mean change in joint line position in extension was -0.0 ± 0.6 mm. Clinical scores at final follow-up were excellent for both groups. CONCLUSIONS: Good TKA outcomes can be achieved in patients with substantial varus or valgus deformities using a combination of a minimally invasive far medial subvastus approach, interchangeable PS implants and soft tissue releases with a piecrust needling technique. LEVEL OF EVIDENCE: III.

Current opinions about coronal plane alignment in total knee arthroplasty: A survey article.

PURPOSE: To survey an audience of international knee surgeons about their current opinions on the analysis of coronal knee alignment and their objectives for postoperative alignment in total knee arthroplasty. METHODS: Survey of 300 surgeons from 32 different countries with an audience response system allowing three possible answers being either a positive or negative answer or an abstention. RESULTS: Surveyed surgeons perform rarely preoperative and postoperative full leg radiographs and evaluate radiological outcomes more with short films. The main trend in this survey was towards neutral mechanical alignment, however varus alignment is acceptable in constitutional varus patients. This residual varus should be obtained through a femoral varus cut rather than a tibial varus cut. The valgus knee can remain in slight valgus but most of the correction will be performed at the femoral level. The main objective of postoperative alignment in TKA is a joint line parallel to the floor and a central load-bearing axis through the middle of the arthroplasty. Surgeons prefer unicompartmental arthroplasty more for themselves than for their patients in case of medial bone on bone arthritis. CONCLUSIONS: Neutral mechanical axis with a joint line parallel to the floor and a centrally running load bearing axis remains the central scope of the surveyed surgeons. Because of the literature on residual varus it becomes more acceptable for the orthopaedic community to accept this type of outlier before aiming at a surgical correction.

Vascular study of decellularized porcine long bones: Characterization of a tissue engineering model.

INTRODUCTION: Massive bone allografts enable the reconstruction of critical bone defects in numerous conditions (e.g. tumoral, infection or trauma). Unfortunately, their biological integration remains insufficient and the reconstruction may suffer from several postoperative complications. Perfusion-decellularization emerges as a tissue engineering potential solution to enhance osseointegration. Therefore, an intrinsic vascular study of this novel tissue engineering tool becomes essential to understand its efficacy and applicability. MATERIAL AND METHODS: 32 porcine long bones (humeri and femurs) were used to assess the quality of their vascular network prior and after undergoing a perfusion-decellularization protocol. 12 paired bones were used to assess the vascular matrix prior (N = 6) and after our protocol (N = 6) by immunohistochemistry. Collagen IV, Von Willebrand factor and CD31 were targeted then quantified. The medullary macroscopic vascular network was evaluated with 12 bones: 6 were decellularized and the other 6 were, as control, not treated. All 12 underwent a contrast-agent injection through the nutrient artery prior an angio CT-scan acquisition. The images were processed and the length of medullary vessels filled with contrast agent were measured on angiographic cT images obtained in control and decellularized bones by 4 independent observers to evaluate the vascular network preservation. The microscopic cortical vascular network was evaluated on 8 bones: 4 control and 4 decellularized. After injection of gelatinous fluorochrome mixture (calcein green), non-decalcified fluoroscopic microscopy was performed in order to assess the perfusion quality of cortical vascular lacunae. RESULTS: The continuity of the microscopic vascular network was assessed with Collagen IV immunohistochemistry (p-value = 0.805) while the decellularization quality was observed through CD31 and Von Willebrand factor immunohistochemistry (p-values <0.001). The macroscopic vascular network was severely impaired after perfusion-decellularization; nutrient arteries were still patent but the amount of medullary vascular channels measured was significantly higher in the control group compared to the decellularized group (p-value <0.001). On average, the observers show good agreement on these results, except in the decellularized group where more inter-observer discrepancies were observed. The microscopic vascular network was observed with green fluoroscopic signal in almost every canals and lacunae of the bone cortices, in three different bone locations (proximal metaphysis, diaphysis and distal metaphysis). CONCLUSION: Despite the aggressiveness of the decellularization protocol on medullary vessels, total porcine long bones decellularized by perfusion retain an acellular cortical microvascular network. By injection through the intact nutrient arteries, this latter vascular network can still be used as a total bone infusion access for bone tissue engineering in order to enhance massive bone allografts prior implantation.

PMMA-cement anterior column reconstruction in surgical treatment of spondylodiscitis.

Introduction and research question: This paper explains how antibiotic loaded cement can be used in surgical treatment of spondylodiscitis to reconstruct the anterior column of the spine. Material and methods: 35 consecutive surgical procedures performed for spondylodiscitis were collected over a 11-year period and charts were reviewed. Most infections were caused mainly by staphylococcus spp (n = 16), streptococcus spp (n = 8) and pseudomonas spp (n = 4). Most patients had long standing but unsuccessful antibiotic therapy (median 42 days). Other indications included instability, neurologic deficit, abscess, and patients were generally in very poor medical condition. Results: Anterior debridement was followed by a partial cavity filling with surgical high viscosity PMMA cement in all cases. Cement was a high viscosity gentamycin loaded cement, that was placed in the cavity created by debridement under the direct eye control. In 25 cases, a part of the cavity was filled with freeze dried cancellous bone allograft rehydrated in rifampicin. Spine was further stabilized with an anterior plate in 15 cases, with short (+1/+1) posterior instrumentation in 5 cases, and a long (≥ +2/+2) posterior instrumentation in 11 cases. In four patients, spine was left un-instrumented. Immediate, unrestricted mobilization was always authorized after surgery. None of the patients were reoperated neither for mechanical failure nor for infection relapse. Conclusion: This report supports the idea that surgical bone cement is an efficient gap filler when used through anterior approach. For small as well as for large defects, it can help to reconstruct the anterior column and locally control the infection in combination with additional stabilization and optimal intravenous and oral antibiotic treatment.

Human tissue allograft processing: impact on in vitro and in vivo biocompatibility.

This work investigates the impact of chemical and physical treatments on biocompatibility for human bone/tendon tissues. Nontreated and treated tissues were compared. In vitro testing assessed indirect and direct cytotoxicity. Tissues were subcutaneously implanted in rats to assess the immunological, recolonization, and revascularization processes at 2-4 weeks postimplantation. No significant cytotoxicity was found for freeze-dried treated bones and tendons in comparison to control. The cellular adhesion was significantly reduced for cells seeded on these treated tissues after 24 h of direct contact. A significant cytotoxicity was found for frozen treated bones in comparison to freeze-dried treated bones. Tissue remodeling with graft stability, no harmful inflammation, and neo-vascularization was observed for freeze-dried chemically treated bones and tendons. Frozen-treated bones were characterized by a lack of matrix recolonization at 4 weeks postimplantation. In conclusion, chemical processing with freeze-drying of human tissues maintains in vitro biocompatibility and in vivo tissue remodeling for clinical application.

Bone allografts: What they can offer and what they cannot.

Bone allografts can be used in any kind of surgery involving bone from minor defects to major bone loss after tumour resection. This review describes the various types of bone grafts and the current knowledge on bone allografts, from procurement and preparation to implantation. The surgical conditions for optimising the incorporation of bone are outlined, and surgeon expectations from a bone allograft discussed.

[Tarsal osteoarthritis: a rare localisation of tuberculosis]. / Ostéoarthrite tarsienne: une localisation rare de la tuberculose.

We report the case of a 39-year-old woman with an uneventful medical history who presented an inflammatory left foot with no notion of trauma or fever. The plain x-ray and magnetic resonance imaging demonstrated talonavicular and subtalar osteoarthritis. A surgical biopsy with excision of inflammatory and necrotic tissue and removal of a fistular tract was performed. Histology revealed the presence of granulomas with caseous central necrosis suggesting tuberculosis of the bone. The diagnosis was confirmed when bacteriology samples grew Mycobacterium tuberculosis. Antituberculosis drugs were administered for twelve months. At 24 months, the patient presents a painful stiff rear foot after the development of secondary talonavicular degeneration. This case illustrates a particular clinical presentation of tuberculosis. This diagnosis should be considered in the presence of atypical bony lesions with a chronic course. Early diagnosis enables proper therapeutic management. Useful diagnostic imaging techniques include plain x-rays, computed tomography, and magnetic resonance imaging. Certain diagnosis is based on bacteriological and histological examinations.

Diagnosis of prosthetic joint infection with alpha-defensin using a lateral flow device: a multicentre study.

AIMS: The purpose of this current multicentre study is to analyse the presence of alpha-defensin proteins in synovial fluid using the Synovasure lateral flow device and to determine its diagnostic reliability and accuracy compared with the prosthetic joint infection (PJI) criteria produced by the Musculoskeletal Infection Society (MSIS). PATIENTS AND METHODS: A cohort of 121 patients comprising 85 total knee arthroplasties and 36 total hip arthroplasties was prospectively evaluated between May 2015 and June 2016 in three different orthopaedic centres. The tests were performed on patients with a chronically painful prosthesis undergoing a joint aspiration in a diagnostic pathway or during revision surgery. RESULTS: Based on the MSIS criteria, 34 patients (28%) would have had a PJI, and 87 patients had no PJI. Testing with the lateral flow device had a sensitivity of 97.1% (95% confidence intervals (CI) 84.5 to 99.9) and a specificity of 96.6% (95% CI 90.3 to 99.2). The positive predictive value was 91.7% (95% CI 77.7% to 98.3), and the negative predictive value was 98.8% (95% CI 93.6 to 99.9). Receiver operator characteristics analysis demonstrated an area under the curve for the Synovasure test of 0.97 (95% CI 0.93 to 1.00). CONCLUSION: Our findings suggest that the Synovasure test has an excellent diagnostic performance to confirm or reject the diagnosis of a PJI. The results are promising for the care of the painful or problematic knee and hip joint arthroplasty and the test should be considered as part of the diagnostic toolbox for PJIs. Cite this article: Bone Joint J 2017;99-B:1176-82.

Nocardia prosthetic knee infection successfully treated by one-stage exchange: case report and review.

A 64-year-old man with a history of sarcoidosis on corticosteroids and azathioprine was admitted to our hospital with complaints of worsening left knee pain and swelling for the past 3 weeks. His past medical history is also significant for severe osteoarthritis requiring a cemented total left knee arthroplasty 1 year ago. Diagnostic investigation during his hospital admission eventually led to the diagnosis of Nocardia nova knee prosthetic joint infection in the setting of a disseminated nocardiosis. He was successful treated by one-stage complete hardware exchange in conjunction with an adapted antibiotic therapy regimen (meropenem and doxycycline followed by ceftriaxone and doxycycline). Two years later, his recovery was deemed excellent.

Inhomogeneity of human vertebral cancellous bone: systematic density and structure patterns inside the vertebral body.

In the spine, cancellous bone quality is usually assessed for the whole vertebral body in a transverse central slice. Correct identification and assessment of the weakest parts of the cancellous bone may lead to better prediction of fracture risk. The density and structural parameters were systematically investigated inside the thoracic (T-9), thoracolumbar (T12-L1), and lumbar (L-4) vertebral bodies of nine subjects. On both sides of the median sagittal plane, anterior and posterior 8.2 mm vertical cores were harvested in the thoracic vertebra. In the thoracolumbar and lumbar vertebrae, external samples were also cored. Peripheral quantitative computed tomographic (pQCT) density analysis of the 136 cores was performed at four different levels, from the lower to the upper endplate. The relatively thin slice thickness (300 microm) and small pixel size (70 microm x 70 microm) was considered sufficient to investigate the structural parameters on the four transverse slices and in the sagittal and coronal planes (total of 816 images). Using a constant threshold a binary image was generated and the morphometric data were extracted. The binary image was further skeletonized and classical strut analysis was performed. Cancellous bone density was 20% higher in the posterior cores than in the anterior and external cores. Moreover, clear vertical inhomogeneity was noted because the lowest half of the vertebral body presented lower density than the upper half (differences ranging from 25% to 15%). All structural parameters were strongly dependent on the location of the measurement. Structural differences between anterior, posterior, and external areas were mild and followed the density patterns. On the other hand, vertical inhomogeneity of the structural parameters was important. For example, in the thoracolumbar and lumbar vertebrae, the numbers of nodes or node-to-node struts were almost twofold higher in the inferior half than in the superior half (p < 0.01), whereas trabecular thickness and number of free-ends presented a center/close-to-endplate structural pattern, with central trabeculae being 15% thicker (p < 0.05) and presenting 30% fewer free-ends (p < 0.01) than the close-to-endplate ones. Variability of density and structural parameters was high and a substantial part of this variability could be explained by the place inside the vertebral body where the measurement was made. The weak part was not in the center of the body but in its upper half where the lower density did not seem to be compensated by a higher structural architecture. Further clinical investigation could enhance fracture prediction by tracking and focusing on the weakest part of the vertebral body.

Physical and chemical processing for a human dura mater substitute.

OBJECT: Allogenic human fascia lata used in neurosurgery, as dura mater substitute, can be associated with a risk of viral and bacterial transmission. Chemical and physical procedures, developed to inactivate virus and bacteria, have been applied to fascia lata. The aim of this study consists in the evaluation of the biological properties of this treated graft. METHODS: Grafts were treated with solvent detergents, freeze-dried for conservation and gamma irradiated (25,000 Gy) for sterilization. The indirect toxicity evaluation was performed by extraction method, according to the International Standard Organization (ISO). First, the cytotoxic effect of each extracts incubated in the presence of human fibroblasts (WI38) was quantitatively assessed by measuring the cell growth, the viability (succinate dehydrogenase activity, MTT), the membrane integrity (uptake of the neutral red by viable cells, NR) as well as the release of lactate dehydrogenase in the culture medium. Second, confocal laser scanning microscopy (CLSM) was used to assess the direct contact between human primary fibroblasts and graft. CLSM was performed at days 3 and 7 after cells loading. RESULTS: No acute cytotoxicity was observed for chemically processed allografts. Cells loaded on the graft have demonstrated a good growth and spreading. CONCLUSIONS: Human fascia lata secured against conventional and non-conventional agents is a fully biocompatible alternative to the available dural graft materials.

In vitro evaluation of acute cytotoxicity of human chemically treated allografts.

In order to minimize the risk of contamination associated with tissue transplantation, tissue banks commonly chemically treat the tissues whenever possible. As viral inactivation uses agents lethal to microorganisms, it is imperative to assure that chemically inactivated tissue remains biocompatible. In vitro assays can be an effective means to assess the acute cytotoxicity of chemically treated human allografts. We have used different types of cells cultured in the presence of treated tissue extract. A standard cell line, a human fibroblast (WI38), which was the same for all the samples, was chosen. In addition, as the banked tissues (bone and fascia lata) were prepared to be used in bone or as a dura mater substitute, two other cell types were also used: an osteoblastic cell line (SaOS-2) and a neuronal cell line (Neuro 2A). Cytotoxic assessment was performed by qualitative evaluation of cell morphology based on confluence, granulation, vacuolization and swelling analysis. In addition, quantitative methods based on the use of neutral red (NR) and 3- (4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) were assayed. Qualitative and quantitative evaluation of fascia lata and bone extracts did not show deleterious effects on cell cultures. These results show that in vitro methods can be appropriate to select a non-toxic procedure before it is used in the human body and that several strong chemical treatments can result in a tissue suitable for human.