Bilateral THA in the same sitting for avascular necrosis of the head of the femur in sickle cell patient: our African experience.

Sickle cell anemia is protective against the malaria protozoan. The heterozygous form of the disease is not fatal, and may cause musculoskeletal disorders when sickling occurs, and small vessels are occluded. When the head of the femur is involved, this may result in hip arthritis, often bilateral, at a young age. This article describes three patients in whom bilateral total hip arthroplasty (THA) was performed in the context of a humanitarian mission in Togo, Africa.

Periprosthetic joint infection from Mycobacterium Tuberculosis in Togo, Africa.

Mycobacterium Tuberculosis infections are moderately frequent in developing countries. Because of migratory flows, these diseases will always have an increasing prevalence even in those countries that do not usually present these types of cases. Extra-pulmonary tuberculosis often affects the musculoskeletal system. The sites most involved are the spine (Pott's disease) and the large joints, especially hips and knees. We describe a patient with tuberculosis of the hip, who underwent total hip arthroplasty.

Kinematic versus mechanical alignment in total knee arthroplasty: a preliminary study.

Despite the great advances of the technology in the joint prosthesis and the high execution rate of total knee arthroplasty (TKA), there are still about 15% of clinical unsatisfactory rate in this surgery. TKAs are currently performed using a mechanical alignment of the knee, correcting varus/valgus deformities with the purpose to achieve a longer implant survivorship, but this surgical technique results in an alteration of the normal knee kinematics. Nowadays, the idea to restore the pre-arthritic alignment of the knee with the goal to obtain a normal kinematics and better functional results becomes more and more consistent and the kinematic alignment (KA) was developed as alternative to the mechanical one. The aim of this preliminary study is to analyse the functional outcomes in patients who underwent KA-TKA in the short-term follow-up and to compare them with those obtained in patients treated by the mechanical alignment (MA) TKA. Therefore, skeletally mature patients, with no history of previous knee surgical procedures, who underwent isolated TKA for knee osteoarthritis, were included in this study. The patients were prospectively divided into two homogeneous groups according to the different surgical techniques performed (KA-TKA and MA-TKA groups). Clinical and functional scores (VAS, KOOS-PS, MCS-12, Final KSS, and Functional KSS) were collected pre- and postoperatively at a mean follow-up of 3 three months. As a result, 26 patients were included in the study, with a mean age of 69.3±7.61 years old (range: 55 - 84 years old). There were 38.5% male and 61.5% female. There were 13 patients in KA-TKA and 13 patients in MA-TKA. Three months after surgery each of the scores tested demonstrated statistically significant better outcomes in KA-TKA, compared to the MA-TKA group. MCS-12 resulted comparable in the two study groups. This preliminary study compares the short-term clinical and functional outcomes between KA and MA in total knee replacement. Further studies are required to confirm these results and to extend the sample size to obtain reliable clinical evidences.

One-stage Bilateral Total Hip Arthroplasty in patient with sickle cell disease and previous Girdlestone procedure on the right side: First presentation in Togo.

80% of Sickle Cell Disease cases are estimated to be in Sub-Saharan Africa. It can lead to various acute and chronic complications and osteonecrosis of the femoral head is one of these. Girdlestone procedure is an option to treat osteonecrosis in patients who could not afford arthroplasty. We report here the first case of bilateral total hip arthroplasty in a patient with a previous Girdlestone procedure on the right side and an osteonecrosis of the femoral hip on the left side.

Clinical anatomy of the meniscus in animal models: pros and cons.

Nowadays, despite the possibility to use in vitro or computer models in research, animal models are still essential. Different animal models are available for meniscal repair investigation. Although a unique perfect model for the structure of the human's knee does not exist, the choice of the proper animal model is crucial for a correct research. The principal animal models in the meniscal repair are sheep, goats, pigs and dogs. Each of these has pros and cons for their utilization. Analysing each pro and con is essential for optimizing the choice of the animal model, which depends on the experimental question, avoiding unnecessary waste of resources and minimizing the animal suffering, according to the Russell and Burch's three "Rs" principles (Reduce, Refine and Recycle). In this concise review, we resume the meniscus anatomical features of the main large animals, to help choose the most suitable animal model for subsequent studies on meniscal repair.

Total hip arthroplasty for osteonecrosis of the femoral head in sickle cell disease: a case series from our African experience.

Sickle cell disease causes osteonecrosis (20% to 50% of patients) and collapse of the femoral head that result in secondary osteoarthritis. Total hip arthroplasty (THA) is a valid alternative for these patients. We define the difficulties that can be encountered when undertaking THA in sickle cell disease patients and give advice on how to deal with these technically demanding procedures. We undertook total hip arthroplasty procedures on 12 patients (4 females and 8 males) with osteonecrosis of the femoral head. Two bilateral prostheses were performed. We had only one type of stem, only one type of acetabular cup and only 28 mm cobalt chrome heads. The procedures were performed through either an anterior or a direct lateral approach. The average size of the Cup was 46 (Versafit, Medacta), the average size of the femoral stem was 0 (Amistem, Medacta), the most used size of the modular head was a S. Standard stem that was used in nine patients, while three patients received a lateralizing stem. Three patients had periprosthetic fracture, treated by cerclage. Total hip replacement is an excellent alternative for patients with osteonecrosis from sickle cell disease. The preparation of the acetabulum and the femur is difficult and requires attention, time and appropriate equipment.

Bone grafiting combined with Sauvé-Kapandji Procedures for the treatment of aseptic distal radius non-union.

Distal radius fractures are the most common type of upper limb fractures in adults. Non-union after distal radius fracture is rare, serious and unpredictable. The aim of our paper is to analyse the clinical and radiological outcomes of bone grafting and Sauvé-Kapandji Procedures for the treatment of aseptic distal radius non-union. We enrolled 13 patients with distal radius aseptic non-union. The following parameters were evaluated: The surgical time, elbow, forearm and wrist range of motion, the subjective quality of life and the wrist function measured by Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH), Pain Visual Analogic Score (VAS) and the complication rate. Bone union was measured using the radiographic union score as described by Radiographic Union Score (RUS). The evaluation endpoint was set at 24 months after surgery. All patients achieved fracture union. Grip strength improved by 12.4 kg. There was also improvement in wrist flexion, in wrist extension, and forearm pronosupination. These ranges of motion and grip strength improvements were statistically significant. Only 6 patients returned to full activity. This surgical technique represents a reliable alternative for treatment of distal radius aseptic non-unions. Further studies are needed to assess the long-term clinical results of this surgical procedure.

When math meets surgery: how to improve femoral interference screw alignment in ACL reconstruction. A cadaveric study.

Transtibial femoral tunnel drilling is still an alternative technique in ACL reconstruction. Femoral interference screw divergence is a potential pitfall associated with transtibial tunnel technique, as angles greater than 15° jeopardize graft fixation. Our mathematical model theorizes the proper degrees of knee flexion during femoral screw insertion and the correct screwdriver position to obtain a minimal divergence of the screw in the femoral tunnel. The cadaveric study confirms our method. Mathematical model: using rototranslation matrices, a correlation is demonstrated between the ACLtibial- guide angle, the knee flexion, and the screwdriver position. A theoretical minimal divergence between femoral interference screw and the femoral tunnel is obtainable following these assumptions: 1) knee hyperflexion during femoral screw insertion is obtained adding a flexion corresponding to the ACL-tibial-guide angle to the flexion while drilling the femoral tunnel; 2) screwdriver position (through the AM portal) is kept parallel to tibial plateau at a rotation of 15° medial to tibial sagittal plane. Cadaveric study: 24 cadaver knees were used. The transtibial tunnel was drilled with an 8 mm drill bit with the help of an ACL tibial guide set at 55°. To simulate femoral tunnel direction, a 2.4 mm K. wire was drilled through the femur with a transtibial 7 mm offset femoral drill guide. To simulate the femoral screw direction, a second 2.4 mm K. wire was drilled from the femoral entry point of the first wire through the femur, with a cannulated screwdriver. Screwdriver direction and knee flexion during the simulation were obtained following two different methods: GROUP A (mathematical model group, 12 knees), screwdriver direction and knee flexion were calculated following the mathematical model; in GROUP B (control group, 12 knees), knee hyperflexion and screwdriver medialization were manually obtained by a senior surgeon. The divergence between the femoral interference screw and the femoral tunnel was identified as the angle formed by the two wires, measured on the plane formed by the direction of the wires. Mean divergence angles between the K. wires were significantly different (p< 0.05) between the groups: GROUP 1 (mathematical rule): 7.25° (SD 2.2); GROUP 2 (free-hand technique): 17.3° (SD 2.9). Our study shows that a minimal divergence between the femoral tunnel and the screwdriver can be achieved simply by following a mathematical rule for correct intraoperative knee flexion and screwdriver position without the need for any specialized instrumentation. Namely, during femoral interference screw insertion through the anteromedial portal: 1) the correct knee flexion is the sum between the knee flexion angle while drilling the transtibial femoral tunnel AND the ACL tibial guide angle used during tibial tunnel drilling; 2) Correct screwdriver position is parallel to the tibial plateau, engaging the femoral tunnel with a position of 15° medial to tibial sagittal plane. This simple concept has clinical relevance in helping the surgeons in obtaining an optimal alignment between the femoral tunnel and the femoral interference screw during transtibial ACL reconstruction. Furthermore, following the assumptions of this study, a starting knee flexion angle around 70° during femoral tunnel drilling seems preferable for ACL reconstruction when the transtibial tunnel technique is used. Indeed, because ACL-tibial-guide angles range commonly from 50° to 60° and in vivo, the maximal intraoperative knee flexion attainable is 130°, a starting knee flexion around 70° is optimal to allows for adding flexion angles up to 60° before reaching the physiological limit value of 130°.

Periprosthetic osteolysis: a narrative review.

Periprosthetic osteolysis is still one of the major limitations of prosthetic joints longevity. The process of this "silent" iatrogenic disease involves both mechanical and biological factors that initiate a local immune response in the periprosthetic tissue that eventually lead to implant loosening and failure. There are many causes of the primary aseptic loosening inside the periprosthetic microenvironment, but the most important elements are the wear debris and the cell-particle interactions. Together with implant position, micromotion, bearings, joint fluid pressure, and increased load on the joints drive the pathogenesis of the disease. This narrative review aims to summarise recent studies describing the biological and mechanical factors in the pathogenesis of osteolysis and some of the current pharmacological attempts to "rescue" a failing implant.

Hamstring grafts are tenogenic constructs for ACL reconstruction and Pulsed Electromagnetic Fields improve tendon specific markers expression. An in-vitro study.

Hamstring tendons represent one of the commonest autologous graft used during ACL reconstruction. The harvest of the tendon and the time of tendon processing on the operating table, together with the pretensioning maneuvers and the permanence out of the joint during the time of surgery, might impair tendon derived cells (TCs) viability. The aim of the study was: i) to assess the effective viability of the TCs at the end of the surgical procedure; ii) to investigate if TCs viability and the expression of tendon specific markers may be improved through exposure to prolonged pulsed electromagnetic fields (PEMF) similar to that of clinical practice. Remnants of semitendinosus and gracilis tendons (discarded at the end of the ACL reconstruction) were collected from 13 healthy donors. To isolate TCs, the tendon tissue was minced and digested enzymatically with 0.3% type I collagenase in DMEM with continuous agitation for 15 h at 37°C. The isolated nucleated cells were then plated at 5x103 cells/cm2 in a complete medium composed of DMEM, 10% fetal bovine serum, 50 U/ml Penicillin, 50 mg/ml Streptomycin, 2 mM L-glutamine, and supplemented with 5 ng/ml basic fibroblast growth factor (b-FGF). They were maintained at 37 °C in a humidified atmosphere with 5% CO2, changing culture medium every 3 days. When they reached 80-90% of confluence, the cells were detached by incubation with trypsin/EDTA and then cultured at a density of 5x103 cells/cm2. TCs were cultured in complete medium for 7, 14, 21 days (in chamber slides, to optimize the final immunofluorescence analysis). The following cell cultures were set up: i) TCs cultured with differentiation medium + exposure to PEMF 8 h/day; ii) TCs cultured with differentiation medium without exposure to PEMF. The stimulation with PEMF was generated by a pair of electrical coils, connected with the generator of pulsed electromagnetic fields (PEMF generator system IGEA, Carpi, Italy, intensity of magnetic field = 1.5 mT, frequency = 75 Hz). At day 0, day 7, day 14 and day 21 immunofluorescence analysis was performed to evaluate the expression of tendon specific markers (collagen type I, collagen type VI, scleraxis) and proliferative markers (PCNA, beta-catenin). The TCs from the hamstring tendon fragments at the end of the ACL reconstruction were alive and they expressed markers of proliferation and tendon phenotype at the end of the culture period. The TCs in the presence of PEMF 8h/day showed a greater production of collagen type I, collagen type VI and scleraxis than TCs cultured without PEMF (p<0.05). The expression of these markers increased from 7 to 21 days of culture. The expression of proliferative markers in the presence of PEMF stimulus was significantly lower (p<0.05) than that of TCs cultured without PEMF. Hamstring tendons are not simple "tenoconductive" scaffolds but biologic alive tenogenic constructs rich in cells that can sustain tenogenic behavior and tendon matrix synthesis. Prolonged exposure to PEMF improves their phenotype. Thus, from a clinical perspective, the use of PEMF may represent a possible future strategy to positively influence the early phase of graft remodeling and, ultimately, improve the ligamentization process. Following these concepts, further studies might also exploit the anabolic role of PEMF as an adjunctive postoperative strategy in different tendon pathologies.

Rehabilitation protocol after simultaneous anterior cruciate ligament reconstruction and high tibial osteotomy: introducing the concept of the individualized approach.

Postoperative rehabilitation after simultaneous anterior cruciate ligament reconstruction and opening wedge high tibial osteotomy is a complex concept. Different osteotomy techniques, extremely selected patients, high expectations in returning to previous sport activities, and the different individual physical profile and performances make traditional chronological criteria impractical and unfeasible. This study presents a novel rehabilitation in which functional objective criteria are considered the key factors for standardizing a 4-step protocol. Each step is "individualized", based on the patient's response to the healing processes and to the different training phases, allowing for a safe return to sports competitions. This definitively implies a strict collaboration between patient, surgeon, physician and physiotherapists, as well as thorough and detailed patient education. Due to the high versatility of these new rehabilitation concepts, the application of the "individualized" steps described in this study may be broadened to include different sports medicine knee injuries that may benefit from a specific, detailed and carefully patient-centered rehabilitation project.

Comparing different approaches in robotic-assisted surgery for unicompartmental knee arthroplasty: outcomes at a short-term follow-up of MAKO versus NAVIO system.

The popularity of unicompartmental knee arthroplasty (UKA) continues to grow among orthopaedic surgeons and robotic surgery may be helpful in obtaining a precise placement of the prosthetic components, thanks to the meticulous intra-operative computer study for simulating the prosthetic positioning. This may lead to longer implant survivorship as well as a reduction in intermediate and long-term prosthetic complications, despite the initial greater costs than those of manual UKA. In this preliminary study, from January 2017 and October 2017, 18 patients underwent UKA with MAKO robotic system assistance and 10 patients received UKA with NAVIO robotic system assistance. The two groups were homogeneous by age, BMI, degree of osteoarthritis involvement, and postoperative program. Patients were followed both clinically (Numeric Rating Scale NRS and Knee Injury Osteoarthritis Outcome Scores KOOS) and radiographically. At the end term follow up (2 years), no significant difference was observed for NRS and KOOS as well as for clinical parameters as an active range of motion. A significant discrepancy was detected regarding the duration of the surgery and time of using the robotic system, that appeared to be longer in the NAVIO group than that of MAKO group, likely due to the specific technical aspects that characterize these two different robotic systems. The main finding of this study is that favorable clinical and radiographical results may be obtained using a robotic approach (MAKO or NAVIO) for UKA positioning at a short follow up. Due to the lack of significant clinical differences observed between the two groups of patients at end term follow up, the "concept" of a robotic approach, more than a specific patented system, may be considered the key element for improving UKA technique and it is likely that in the near future the choice of a single specific robotic system will still be a "surgeon's preference". The results of the study add scientific evidence regarding the effective improvement of UKA results using different robotic approaches. They also show possible economic sustainability of this therapeutic strategy related to the optimal patients' performance obtained at short term follow up, suggesting that the robotic assistance may really become a key element for better long-term survivorship of unicompartmental knee arthroplasty.

Tips and tricks for writing a scientific manuscript.

An original scientific manuscript is the target for any researchers whose aim is to show the innovative results arising from the original intuitions that drove all their experiments. Time and patience are essential to decide how to present the data, how to conceive the tables and figures representing the main outcomes of the research, and how to read and mention the necessary references. Few basic rules may help in this difficult task. The first basic rule is: "do not follow the sequence of the paper". On the opposite, i) start writing the "Materials and Methods (or Patients and Methods when dealing with a clinical study)", ii) then write the "Results" section, iii) then, write the "Discussion" paragraph, in which the principal investigator explains the results and the innovations proposed, iv) then, write the "Introduction", which should be clear and concise. The last element to be written should be the "Abstract", which is the "interface" between the authors and the readers. The second basic rule is that any of the central chapters of the manuscript, i.e. "Materials and Methods" (MM), "Results" (R) and "Discussion" (D), should follow a methodical and sequential description of the topics in a "corresponding sequence of paragraphs". In other words, in the R and the D chapter sequence of the paragraphs should be linked to the sequence of the concepts described and discussed in the paragraphs of the MM chapter. Thus, a sequential description of concepts will be easily followed by the writers, facilitating both the authors in the organization of the data and the reader in finding a reasonable "answer" to all the aspects of the study mentioned in the MM chapter. In this article, these two rules are extensively described and several tips and tricks for each chapter are suggested to ease the composition of a scientific paper. Indeed, it may be possible to solve the complex problem of "writing a scientific paper" by means of separating it in main sections (chapters) and subsections (paragraphs) and dealing with them one by one. Naturally, this takes time and passion, but, as affirmed by Steve Jobs, "the only way to do great work is to love what you do".

Current trends in tendinopathy: consensus of the ESSKA basic science committee. Part II: treatment options.

The treatment of painful chronic tendinopathy is challenging. Multiple non-invasive and tendon-invasive methods are used. When traditional non-invasive treatments fail, the injections of platelet-rich plasma autologous blood or cortisone have become increasingly favored. However, there is little scientific evidence from human studies supporting injection treatment. As the last resort, intra- or peritendinous open or endoscopic surgery are employed even though these also show varying results. This ESSKA basic science committee current concepts review follows the first part on the biology, biomechanics and anatomy of tendinopathies, to provide a comprehensive overview of the latest treatment options for tendinopathy as reported in the literature.

One-step cartilage repair with minced chondral fragment on a composite scaffold: an in vitro human study at low oxygen tension.

Minced cartilage fragments are a viable cell source for one stage cartilage repair. However, the joint surface is a low oxygen tension microenvironment and little evidence is present in literature regarding the behaviour of cartilage fragments in this peculiar condition. The aim of the study is i) to verify if low oxygen tension could negatively influence chondrocyte outgrowth from cartilage fragments into a Hyaluronic-Acid(HA)/fibrin scaffold and ii) to evaluate its effects on the behaviour of migrating chondrocyte, compared to normoxic condition. A slight decrease in chondrocyte migration and proliferation was observed in low oxygen tension cultures. Conversely, an increase in the expression of SOX9, ß-catenin, HIFs, collagen-I and II (p<0.05) in migrating chondrocytes from low oxygen tension cultures was present. Thus, a long term- exposure at low oxygen tension seems to improve the chondrocytic phenotype expression of cell outgrowing from cartilage fragments onto a HA/fibrin scaffold.

Histological changes of the meniscus following an osteochondral lesion.

In the last few years, different tissue engineering strategies have been developed for the repair of osteochondral lesions. When the osteochondral scaffold is implanted on the femoral condyle, the meniscus might be affected by the implant and might undergo a progressive degeneration. The aim of our study is to analyze the morphological changes of the meniscus following an osteochondral lesion and the implant of a biphasic scaffold. A critical osteochondral defect was generated in the medial femoral condyle of mature sheep. Three defects were left untreated, the remaining lesions were divided into three groups and treated with a biphasic substituted formed by collagen type I and Wollastonite or Wollastonite/Hydroxyapatite. Animals were sacrificed after 6 months and menisci were isolated and analyzed by arthro-CT, macroscopic evaluation and histology. The results demonstrated that the osteochondral lesion negatively affects meniscus morphology and that the osteochondral substitute only partially mitigates the meniscus degeneration.

Current trends in tendinopathy: consensus of the ESSKA basic science committee. Part I: biology, biomechanics, anatomy and an exercise-based approach.

Chronic tendinopathies represent a major problem in the clinical practice of sports orthopaedic surgeons, sports doctors and other health professionals involved in the treatment of athletes and patients that perform repetitive actions. The lack of consensus relative to the diagnostic tools and treatment modalities represents a management dilemma for these professionals. With this review, the purpose of the ESSKA Basic Science Committee is to establish guidelines for understanding, diagnosing and treating this complex pathology.

Allogeneic Umbilical Cord-Derived Mesenchymal Stem Cells as a Potential Source for Cartilage and Bone Regeneration: An In Vitro Study.

Umbilical cord (UC) may represent an attractive cell source for allogeneic mesenchymal stem cell (MSC) therapy. The aim of this in vitro study is to investigate the chondrogenic and osteogenic potential of UC-MSCs grown onto tridimensional scaffolds, to identify a possible clinical relevance for an allogeneic use in cartilage and bone reconstructive surgery. Chondrogenic differentiation on scaffolds was confirmed at 4 weeks by the expression of sox-9 and type II collagen; low oxygen tension improved the expression of these chondrogenic markers. A similar trend was observed in pellet culture in terms of matrix (proteoglycan) production. Osteogenic differentiation on bone-graft-substitute was also confirmed after 30 days of culture by the expression of osteocalcin and RunX-2. Cells grown in the hypertrophic medium showed at 5 weeks safranin o-positive stain and an increased CbFa1 expression, confirming the ability of these cells to undergo hypertrophy. These results suggest that the UC-MSCs isolated from minced umbilical cords may represent a valuable allogeneic cell population, which might have a potential for orthopaedic tissue engineering such as the on-demand cell delivery using chondrogenic, osteogenic, and endochondral scaffold. This study may have a clinical relevance as a future hypothetical option for allogeneic single-stage cartilage repair and bone regeneration.

The meniscus vascularization: the direct correlation with tissue composition for tissue engineering purposes.

Meniscal lesions still represent an unsolved problem in clinical practice. Like the articular cartilage, meniscus has a scarce healing potential. Thus, when this tissue is damaged, the joint biomechanics is completely altered, leading to the development and progression of premature osteoarthritis. Therefore, in the last years, several tissue-engineering strategies have been developed to regenerate the meniscus with debated results. The comprehension of complex processes underlying meniscus maturation and structure is essential for a correct approach for the generation of a biomimetic meniscal substitute. In this chapter, we will first review the morphology of the meniscus during growth, focusing on the unique pattern of vascularization, and then we will discuss the most common tissue engineering strategies for meniscus repair.

Tranexamic acid effects on cartilage and synovial tissue: an in vitro study for a possible safe intra-articular use.

The possible toxic effects of intra-articular tranexamic acid (TA) are still debated. The aim of this study was to evaluate TA effects on human cartilage fragments and synovial biopsies. Explant culture of minced articular cartilage underwent prolonged TA exposure. Histological analysis, immunofluorescence and colorimetric assay for quantification of s-GAG and DNA were performed at the end term. Synoviocytes were cultured for 48h in presence of TA. Light microscopy and flow cytometry analysis were performed at the end of the exposure to TA and one week after the treatment. TA exposure did not influence i) the chondrocyte outgrowth and migration, ii) the expression of chondrogenic and proliferative markers and iii) the s-GAG/DNA ratio. TA treatment did not affect synoviocytes' morphology and treated cells were phenotypically similar to control cells. This study demonstrated that TA does not negatively affect chondrocytes and synoviocytes cultured in vitro. Thus, our findings may be clinically relevant in order to validate the intra-articular TA administration during orthopedic procedures.