Intermediate-Term Clinical Outcomes of High-Density Autologous Chondrocyte Implantation in Patients with Concomitant Anterior Cruciate Ligament Reconstruction and Focal Chondral Lesions.

OBJECTIVE: To investigate intermediate-term clinical results in patients with concomitant anterior cruciate ligament (ACL) reconstruction and chondral defect treated with high-density autologous chondrocyte implantation (HD-ACI) compared to patients without ACL tear but with a chondral lesion and HD-ACI treatment. DESIGN: Forty-eight patients with focal chondral lesions underwent HD-ACI (24 with ACL reconstruction after an ACL injury and 24 with an intact ACL). Follow-up assessments occurred at 6, 12, and 24 months. Patient-reported knee function and symptoms were assessed using the International Knee Documentation Committee (IKDC) questionnaire, pain was measured using the Visual Analog Scale (VAS), and adverse events were monitored. Physical activity was assessed using the Tegner Activity Level Scale, and cartilage healing was evaluated with the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. RESULTS: No significant adverse events occurred during follow-up. Both groups showed significant improvements at 2 years compared to baseline (VAS: 8.0 ± 1.3 to 1.4 ± 2.0 [normal ACL]; 7.4 ± 2.3 to 2.1 ± 2.3 [ACL reconstruction]; IKDC: 39.2 ± 10.6 to 76.1 ± 22.0 [intact ACL]; 35.6 ± 12.1 to 74.6 ± 20.9 [ACL reconstruction]). Patients in both groups exceeded the minimal clinically important difference (MCID) for IKDC scores. The Tegner Activity Level Scale decreased immediately after surgery and increased after 2 years, with 70.6% (normal ACL) and 89.5% (ACL reconstruction) returning to their preinjury activity levels. No significant differences in the MOCART score were observed between the groups. CONCLUSIONS: ACL reconstruction does not appear to reduce the outcomes (at 2 years) of HD-ACI.

Genome-wide CRISPR activation screening in senescent cells reveals SOX5 as a driver and therapeutic target of rejuvenation.

Our understanding of the molecular basis for cellular senescence remains incomplete, limiting the development of strategies to ameliorate age-related pathologies by preventing stem cell senescence. Here, we performed a genome-wide CRISPR activation (CRISPRa) screening using a human mesenchymal precursor cell (hMPC) model of the progeroid syndrome. We evaluated targets whose activation antagonizes cellular senescence, among which SOX5 outperformed as a top hit. Through decoding the epigenomic landscapes remodeled by overexpressing SOX5, we uncovered its role in resetting the transcription network for geroprotective genes, including HMGB2. Mechanistically, SOX5 binding elevated the enhancer activity of HMGB2 with increased levels of H3K27ac and H3K4me1, raising HMGB2 expression so as to promote rejuvenation. Furthermore, gene therapy with lentiviruses carrying SOX5 or HMGB2 rejuvenated cartilage and alleviated osteoarthritis in aged mice. Our study generated a comprehensive list of rejuvenators, pinpointing SOX5 as a potent driver for rejuvenation both in vitro and in vivo.

Cartilage Defect Treatment Using High-Density Autologous Chondrocyte Implantation (HD-ACI).

Hyaline cartilage's inability to self-repair can lead to osteoarthritis and joint replacement. Various treatments, including cell therapy, have been developed for cartilage damage. Autologous chondrocyte implantation (ACI) is considered the best option for focal chondral lesions. In this article, we aimed to create a narrative review that highlights the evolution and enhancement of our chondrocyte implantation technique: High-Density-ACI (HD-ACI) Membrane-assisted Autologous Chondrocyte Implantation (MACI) improved ACI using a collagen membrane as a carrier. However, low cell density in MACI resulted in softer regenerated tissue. HD-ACI was developed to improve MACI, implanting 5 million chondrocytes per cm2, providing higher cell density. In animal models, HD-ACI formed hyaline-like cartilage, while other treatments led to fibrocartilage. HD-ACI was further evaluated in patients with knee or ankle defects and expanded to treat hip lesions and bilateral defects. HD-ACI offers a potential solution for cartilage defects, improving outcomes in regenerative medicine and cell therapy. HD-ACI, with its higher cell density, shows promise for treating chondral defects and advancing cartilage repair in regenerative medicine and cell therapy.

Consensus Delphi study on guidelines for the assessment of anterior cruciate ligament injuries in children.

BACKGROUND: Knee examination guidelines in minors are intended to aid decision-making in the management of knee instability. CLINICAL QUESTION: A Delphi study was conducted with a formal consensus process using a validated methodology with sufficient scientific evidence. A group consensus meeting was held to develop recommendations and practical guidelines for use in the assessment of instability injuries in children. KEY FINDINGS: there is a lack of evidence to analyse anterior cruciate ligament injuries in children and their subsequent surgical management if necessary. Diagnostic guidelines and clinical assessment of the patient based on a thorough examination of the knee are performed and a guide to anterior cruciate ligament exploration in children is developed. CLINICAL APPLICATION: In the absence of a strong evidence base, these established guidelines are intended to assist in that decision-making process to help the clinician decide on the most optimal treatment with the aim of benefiting the patient as much as possible. Following this expert consensus, surgical treatment is advised when the patient has a subjective sensation of instability accompanied by a pivot shift test ++, and may include an anterior drawer test + and a Lachman test +. If these conditions are not present, the conservative approach should be chosen, as the anatomical and functional development of children, together with a physiotherapy programme, may improve the evolution of the injury.

In vivo partial reprogramming of myofibers promotes muscle regeneration by remodeling the stem cell niche.

Short-term, systemic expression of the Yamanaka reprogramming factors (Oct-3/4, Sox2, Klf4 and c-Myc [OSKM]) has been shown to rejuvenate aging cells and promote tissue regeneration in vivo. However, the mechanisms by which OSKM promotes tissue regeneration are unknown. In this work, we focus on a specific tissue and demonstrate that local expression of OSKM, specifically in myofibers, induces the activation of muscle stem cells or satellite cells (SCs), which accelerates muscle regeneration in young mice. In contrast, expressing OSKM directly in SCs does not improve muscle regeneration. Mechanistically, expressing OSKM in myofibers regulates the expression of genes important for the SC microenvironment, including upregulation of p21, which in turn downregulates Wnt4. This is critical because Wnt4 is secreted by myofibers to maintain SC quiescence. Thus, short-term induction of the Yamanaka factors in myofibers may promote tissue regeneration by modifying the stem cell niche.

High-Density Autologous Chondrocyte Implantation as Treatment for Ankle Osteochondral Defects.

PURPOSE: Two-year follow-up to assess efficacy and safety of high-density autologous chondrocyte implantation (HD-ACI) in patients with cartilage lesions in the ankle. DESIGN: Twenty-four consecutive patients with International Cartilage repair Society (ICRS) grade 3-4 cartilage lesions of the ankle were included. Five million chondrocytes per cm2 of lesion were implanted using a type I/III collagen membrane as a carrier and treatment effectiveness was assessed by evaluating pain with the visual analogue scale (VAS) and American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score at baseline, 12-month, and 24-month follow-up, together with dorsal and plantar flexion. Magnetic resonance observation for cartilage repair tissue (MOCART) score was used to evaluate cartilage healing. Histological study was possible in 5 cases. RESULTS: Patients' median age was 31 years (range 18-55 years). Median VAS score was 8 (range 5-10) at baseline, 1.5 (range 0-8) at 12-month follow-up, and 2 (rang e0-5) at 24-month follow-up (P < 0.001). Median AOFAS score was 39.5 (range 29-48) at baseline, 90 (range 38-100) at 12-month follow-up, and 90 (range 40-100) at 24-month follow-up (P < 0.001). Complete dorsal flexion significantly increased at 12 months (16/24, 66.7%) and 24 months (17/24, 70.8%) with regard to baseline (13/24, 54.2%) (P = 0.002). MOCART at 12- and 24-month follow-ups were 73.71 ± 15.99 and 72.33 ± 16.21. Histological study confirmed that neosynthetized tissue was cartilage with hyaline extracellular matrix and numerous viable chondrocytes. CONCLUSION: HD-ACI is a safe and effective technique to treat osteochondral lesions in the talus, providing good clinical and histological results at short- and mid-term follow-ups.

Proposal for a Clinical Analysis of Patellar Tendon Pathologies: In Search of Efficient Therapeutic Indications.

Development and advances in our understanding of basic sciences such as anatomy, biochemistry, histology, and biomechanics have led to a better knowledge of tendon injuries. Likewise, technological advances in available therapies have conditioned the rise of new therapeutic techniques, turning both diagnosis and therapeutic indications into the foundation of treatment for patellar tendon disorders. Furthermore, we often find no correlation between patellar tendon function and structure, as studied and diagnosed from images taken and referred symptoms. This statement proposes an analytic procedure that ensures a specific therapeutic goal instead of applying a specific drug or therapeutic technique, with the aim of establishing parameters that define the kind of tendinopathy clinicians see, taking into account all conditioning factors that may affect a patellar tendinopathy. These include etiological factors, systemic illnesses affecting tendons, local mechanical causes and clinical presentation, range of clinical presentations, symptom persistence, and pain location, as well as those factors described by echography, with or without the presence of neoangiogenesis and location of the pathology, and magnetic resonance imaging. Diagnosing patellar tendinopathies requires deployment of a complex and thorough assessment process for each individual case and should include all variables that basic sciences have provided. Once a diagnosis has been made, a therapeutic strategy that includes all existing variables should be established. The more precise a diagnosis is, the more selective the treatment options become.

Mutations in foregut SOX2+ cells induce efficient proliferation via CXCR2 pathway.

Identification of the precise molecular pathways involved in oncogene-induced transformation may help us gain a better understanding of tumor initiation and promotion. Here, we demonstrate that SOX2+ foregut epithelial cells are prone to oncogenic transformation upon mutagenic insults, such as KrasG12D and p53 deletion. GFP-based lineage-tracing experiments indicate that SOX2+ cells are the cells-of-origin of esophagus and stomach hyperplasia. Our observations indicate distinct roles for oncogenic KRAS mutation and P53 deletion. p53 homozygous deletion is required for the acquisition of an invasive potential, and KrasG12D expression, but not p53 deletion, suffices for tumor formation. Global gene expression analysis reveals secreting factors upregulated in the hyperplasia induced by oncogenic KRAS and highlights a crucial role for the CXCR2 pathway in driving hyperplasia. Collectively, the array of genetic models presented here demonstrate that stratified epithelial cells are susceptible to oncogenic insults, which may lead to a better understanding of tumor initiation and aid in the design of new cancer therapeutics.

Study of Telomere Length in Preimplanted Cultured Chondrocytes.

DESIGN: In the process of cell division, the extremes of the eukaryotic chromosomes are progressively shortening, and this phenomenon is related to cell degeneration and senescence. The treatment of cartilage lesions with autologous chondrocytes implies that cells proliferate in an artificial environment. We have studied the viability of cultured chondrocytes after measurement of their telomere length before implantation. METHODS: Articular cartilage biopsies (B1, B2, and B3) were obtained from 3 patients (2 males and 1 female) with knee cartilage defects, who were going to be treated with chondrocyte implantation. Chondrocytes were cultured in DMEM with autologous serum. After the third passage, an aliquot of 1 million cells was removed to estimate the telomere length and the remaining cells were implanted. Telomere length was measured by quantitative fluorescent in situ hybridization (Q-FISH). Patients' clinical outcome was determined preoperatively, and 12 and 24 months postimplantation with the International Knee Documentation Committee (IKDC) questionnaire. RESULTS: After chondrocyte implantation, IKDC score doubled at 12 and 24 months with regard to the basal value. After 3 passages, chondrocytes were cultured for a mean of 45.67 days, the mean duplication time being 4.53 days and the mean number of cell divisions being 10.04 during the culture period. The 20th percentile of telomere lengths were 6.84, 6.96, and 7.06 kbp and the median telomere lengths 10.30, 10.47, and 10.73 kbp, respectively. No significant correlation was found between IKDC score and telomere length. CONCLUSION: Culturing autologous chondrocytes for implantation is not related to cell senescence in terms of telomere length.

Cartilage Defect Treatment Using High-Density Autologous Chondrocyte Implantation: Two-Year Follow-up.

OBJECTIVE: The aim of this work was to study the short- and mid-term effectiveness and safety of high-density autologous chondrocyte implantation (HD-ACI) in the first 50 patients with knee cartilage damage treated in our unit. DESIGN: Fifty consecutive patients with cartilage lesions (Outerbridge grade III-IV) in the knee treated with HD-ACI were included in this study. Chondrocytes were isolated from a nonbearing cartilage area biopsy and were cultured until 40 to 50 million cells were obtained. Five million chondrocytes per cm2 of a porcine collagen type I/III membrane were implanted covering the defect. Procedure effectiveness was assessed by evaluating pain, swelling, and range of mobility (flexion and extension) at 6-, 12-, and 24-month follow-up. The International Knee Documentation Committee (IKDC) subjective evaluation form was used to evaluate symptoms and functions of the knee. RESULTS: The percentage of patients with pain and swelling decreased progressively in the following visits, with differences being statistically significant ( P < 0.001 and P = 0.040, respectively). IKDC scores improved progressively throughout the 24-month follow-up ( P < 0.001). Thus, the mean IKDC score improvement was 26.3 points (95% confidence interval [CI] = 18.2-34.4 points) at 12 months and 31.0 points (95% CI = 22.9-39 points) at 24 months. No significant differences were found when performing extension ( P = 0.112). Flexion significantly improved by 25.1° at 24-month follow-up ( P = 0.013). CONCLUSIONS: HD-ACI is a safe and effective technique for the treatment of cartilage defects, improving clinical and subjective perception of knee functionality. These preliminary results encourage future studies comparing this technique with traditional ACI.

Criterios para el retorno al deporte después de una lesión / Criteria to return to play sports after an injury

Uno de los retos más decisivos a los cuales se enfrenta el médico y traumatólogo del deporte es la toma de decisión de cuándo el deportista que ha sufrido una lesión puede reincorporarse a la práctica deportiva. Para la toma de decisión el médico responsable tendrá que tener en cuenta distintos parámetros, como son: el tipo de deporte; el gesto técnico deportivo que tiene que realizar; el tiempo y las fases de la recuperación biológica de la lesión; la recuperación de los parámetros funcionales y la completa superación mental o psicológica de la lesión. En este trabajo, vamos ir desgranando las distintas particularidades que es preciso tener en cuenta para una toma de decisión adecuada con el fin de evitar las complicaciones, recaídas y que el deportista vuelva al mismo nivel deportivo previo a sufrir la lesión. Valoraremos la lesión en general y no la particularidad de cada una de ellas. Es importante valorar cada parámetro de forma individual y a la vez de forma colectiva. No puede ser dado de alta deportiva y autorizado a reincorporarse al deporte si no tiene todos los parámetros en los niveles adecuados. Estableceremos distintos criterios: biológico; funcional; deportivo y criterio psicológico para que el análisis en su conjunto nos pueda ayudar a la toma de la decisión mas adecuada a cada deportista y a su lesión. Consideramos que existen tres altas a nivel de la traumatología del deporte. El alta médica, cuando deportista deja de ser un enfermo y puede comenzar la preparación física. Alta deportiva, que acontece cuando ha terminado la preparación física general y está apto para los entrenamientos específicos de su especialidad deportiva, y por último, el alta de competición, después del cual el deportista puede competir. Proponemos una lista para el chequeo y toma de decisión de cualquier lesión deportiva, que sirva de base para posteriores estudios y modificaciones que concreten este importante reto de la medicina deportiva

One of the most decisive challenges clinicians and sports medicine specialists face is deciding when an athlete who has just come out of injury may return to play. To take such a decision, the corresponding doctor must keep in mind several parameters such as: kind of sport, technical gesture to be performed in the sport, time of injury and it’s biological recovery stages; recovery of functional parameters and finally a full psychological recovery from such an injury. In this paper, we will explain in detail the various specific features which are to be considered in order to take a suitable decision with the aim of avoiding complications, recidives and thus enabling the athlete to return to his/her state of form, prior to the injury. We will provide a general evaluation of the injury without considering specific aspects each injury may show. Each variable must be both individually and collectively considered. An athlete should not be given the ok to return to play unless all criteria show adequate values. We will establish various criteria: biological, functional, sport specific and psychological in order to obtain an overall analysis which will enable us to take the most adequate decision for each athlete and his/her injury. We believe a patient may receive the trauma specialist’s OK from three points of view: The clinical OK, received when the athlete is no longer "ill" and may begin his physical training regime. The sports activity OK which takes place when his general physical training period has terminated and is prepared to undergo workout sessions specific to his sport specialty and finally the competition OK, after which athletes can return to competition. We propose a decision taking and check list for any sport injury which may be used as future reference for subsequent studies and possible modifications that may further help to define this important challenge in sports medicine

Viability of Pathologic Cartilage Fragments as a Source for Autologous Chondrocyte Cultures.

OBJECTIVE: To study if a culture of chondrocytes can be obtained from pathologic hyaline cartilage (PHC) fragments. DESIGN: Twenty-five men and 9 women with osteochondritis dissecans (OCD) in 11 cases, arthrosis in 13 patients, and trauma in the remaining 10 cases were included. The PHC fragments and a small sample of the next healthy cartilage were extracted by arthroscopy. According to the appearance, the PHC samples were divided into fixed (3 cases), flapped (6 patients), or loose bodies (25 cases), depending on the attachment degree of the cartilage to the subchondral bone. Approximately half of each pathologic sample and the whole healthy one were digested to isolate the cells trying to establish the cell culture. RESULTS: We were able to establish a cell culture in 7 out of 34 (20.6%) PHC samples (positive samples), whereas in the remaining 27 (79.4%) no cell growth was observed (negative samples). Most of the negative samples were loose bodies (P = 0.005) taken from patients with OCD or arthrosis (P = 0.001) with an evolution time of more than 1 year (P < 0.001). The best binary logistic regression model (P < 0.001) showed that the only factor affecting the establishment of cell culture was the evolution time (P = 0.044). CONCLUSION: It is possible to culture chondrocytes from osteochondral fragments if they are traumatic, within a year of injury and not from fragments due to arthrosis or OCD.

Epidemiology of injuries in the Spanish national futsal male team: a five-season retrospective study.

BACKGROUND: Futsal started being played in 1930 and the number of futsal players has increased all over the world ever since. Nonetheless, despite the fact that Spain is one of the most relevant national teams worldwide, information on the incidence of injuries and their anthropometric characteristics is sparse in this country. AIM: To analyse medical assistance provided to players in their prematch concentration camps with the Spanish national team over five seasons, from 2010-2011 to 2014-2015, and also to collect data regarding anthropometric characteristics. MATERIALS AND METHODS: This is a retrospective and detailed study of injuries players suffered over these five seasons. All variables were registered on an Excel spreadsheet and later analysed statistically. RESULTS: 411 injuries were studied in total. The dominant somatotype was mesomorph and the injured pivots were both the most endomorphic and the most mesomorphic. The most injured body structure was the hamstring muscles, occurring due to training and intrinsic mechanisms, where fatigue was the most frequent diagnosis. Only a few complementary examinations were carried out and prematch withdrawal was rare. DISCUSSION: The skinfold test total sum was lower than that of the Spanish 11-a-side players or than that in the lower category futsal Spanish players. In various research studies analysing exclusively injuries occurring in matches, the most frequent injury is ligament injury by extrinsic mechanism. The body mass index was not a useful parameter when assessing players' appropriate weight. Most injuries occurred in training sessions, mostly by intrinsic mechanism; the highest percentage of traumatic injuries occurred in official matches.

The Importance of the Intercondylar Notch in Anterior Cruciate Ligament Tears.

BACKGROUND: The factors associated with anterior cruciate ligament (ACL) tears are not completely clear. Some studies have shown that patients with a narrow intercondylar notch have a predisposition for ACL tears. PURPOSE: To determine the relationship between the α angle and intercondylar notch width measurements and ACL tears. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A total of 530 patients (308 with ACL rupture, 222 with healthy ACLs) were included in this study. The α angle and intercondylar width were measured from magnetic resonance images (MRIs). Binary logistic regression analysis was performed to determine the influence of the variables on ACL status (normal or torn). Odds ratios (ORs) and their respective 95% CIs were also calculated. RESULTS: No significant differences in patient age and the affected knee were found between patients with normal or torn ACLs. The mean α angle was higher in patients with a torn ACL than in those with an intact one (57.5° ± 5.5° vs 56.2° ± 4.5°; P = .009). Intercondylar width was significantly lower in patients with a torn ACL than in those with an intact one (18.2 ± 3.1 vs 19.5 ± 3.6 mm; P < .001). A highly significant difference between men and women was found for mean intercondylar notch width (19.3 ± 3.3 vs 17.4 ± 3.1 mm; P < .001). In a logistic regression model, sex, intercondylar width, and α angle were statistically significant when adjusted for age. CONCLUSION: Study results suggest that the ACL tears are associated with a narrow intercondylar notch and a high α angle, and that tears occur more frequently in men than in women. CLINICAL RELEVANCE: The model proposed in this study could be used by the physician in the medical office as a tool to identify the risk factors that may predispose a patient for a potential ACL tear.

Increasing the Dose of Autologous Chondrocytes Improves Articular Cartilage Repair: Histological and Molecular Study in the Sheep Animal Model.

BACKGROUND: We hypothesized that implanting cells in a chondral defect at a density more similar to that of the intact cartilage could induce them to synthesize matrix with the features more similar to that of the uninjured one. METHODS: We compared the implantation of different doses of chondrocytes: 1 million (n = 5), 5 million (n = 5), or 5 million mesenchymal cells (n = 5) in the femoral condyle of 15 sheep. Tissue generated by microfracture at the trochlea, and normal cartilage from a nearby region, processed as the tissues resulting from the implantation, were used as references. Histological and molecular (expression of type I and II collagens and aggrecan) studies were performed. RESULTS: The features of the cartilage generated by implantation of mesenchymal cells and elicited by microfractures were similar and typical of a poor repair of the articular cartilage (presence of fibrocartilage, high expression of type I collagen and a low mRNA levels of type II collagen and aggrecan). Nevertheless, in the samples obtained from tissues generated by implantation of chondrocytes, hyaline-like cartilage, cell organization, low expression rates of type I collagen and high levels of mRNA corresponding to type II collagen and aggrecan were observed. These histological features, show less variability and are more similar to those of the normal cartilage used as control in the case of 5 million cells implantation than when 1 million cells were used. CONCLUSIONS: The implantation of autologous chondrocytes in type I/III collagen membranes at high density could be a promising tool to repair articular cartilage.

De la anti-inflamación a la regulación de la inflamación en las lesiones deportivas / From the anti-inflammation to the regulation of inflammation in sports injuries

Desde la antigüedad se pensaba que la inflamación era un proceso patológico que debía ser bloqueado con los medios terapéuticos disponibles, este pensamiento ha hecho que el uso de técnicas y fármacos antiinflamatorios proliferen y sean de practica habitual, extendida e indiscriminada en la población en general y en los deportistas en particular. Los conocimientos de la biología y fisiología de la reparación de los tejidos demuestran cada vez con más frecuencia que el proceso inflamatorio pone en marcha los mecanismos intrínsecos de reparación y regeneración de los tejidos dañados de forma traumática, circunstancia frecuente en el mundo del deporte. El presente artículo define a la inflamación como el conjunto de fenómenos bioquímicos y celulares que ponen en marcha los mecanismos para la restauración del tejido lesionado, por otra parte, realiza una revisión de los conocimientos actuales sobre la reparación y regeneración tisular de los tres tejidos principales del aparato locomotor (hueso, músculo y tendón),y explica las fases de inflamación, de degeneración y revascularización, de proliferación celular y producción de la matriz extracelular, y por último, la fase de modelación y adaptación funcional. La evolución de un tejido dañado hacia fibrosis o regeneración completa dependerá de qué hecho bioquímico o celular predomine en el foco de la lesión durante la fase inflamatoria, por este hecho deberíamos comenzar hablar de la regulación de la inflamación y abandonar la anti-inflamación. Se hacen necesarios más estudios e investigaciones de ciencias básicas para definir los nuevos tratamientos ante la lesión deportiva y su utilización por los clínicos (AU)

In ancient times inflammation was regarded as a pathological process that had to be blocked with all the therapeutic means available. This thought has made the use of anti-inflammatory drugs and techniques proliferate and become of common practice, widespread and indiscriminately used in the general population and especially in athletes. The knowledge of the biology and physiology of tissue repair shows increasingly more often that the inflammatory process starts internal mechanisms of repair and regeneration of the tissue damaged by trauma, this being a common situation in the world of sports. This article defines inflammation as the set of biochemical and cellular mechanisms that start the restoration processes in the damaged tissue. It also reviews the current knowledge about tissue repair and regeneration of the three main musculoskeletal tissues (bone, muscle and tendon). Furthermore, it explains the phases of inflammation, degeneration and revascularization, cell proliferation and production of extracellular matrix, and lastly, there modeling phase and functional adaptation. The evolution of a damaged tissue to either fibrosis or complete regeneration depends on the predominant biochemical or cellular process in the site of injury during the inflammatory phase. For this reason, we should start talking about the regulation of inflammation and abandon the anti-inflammation concept. More studies and basic sciences research are needed in order to define new ways to treat sports injuries and to use it for clinicians (AU)

Conceptos actuales de la lesión tendinosa. Criterios terapéuticos / Current concepts of the tendon injury. Therapeutic criteria

La lesión del tendón es frecuente en la practica deportiva, produce daño en la estructura del tendón cuya reparación en algunos casos es defectuosa, produciéndose una tendinopatía. Todavía no se conoce con exactitud la biología del tendón y el tratamiento de sus lesiones sigue siendo controvertido. Los conocimientos actuales hacen pensar que el tendón es una estructura dinámica que está en un proceso continuo de regeneración/ degradación. Los agentes lesivos, alteran este equilibrio produciendo la lesión .En este trabajo exponemos algunos agentes lesivos, nivel de actuación y su mecanismo de acción. Su conocimiento se hace imprescindible para asentar el criterio terapeútico afín de aplicar el tratamiento adecuado a cada lesión tendinosa (AU)

The injury of the tendon is frequent when practicing sports; it produces damages in the tendon´s structure sometimes the treatment becoming defective in this one, producing a tendinopathy. Not yet known exactly tendon biology and treatment of his injuries remains controversial. Current knowledge suggests that the tendon is a dynamic structure that is in continuous process of regeneration/ degradation. Damaging agents, alter this balance causing the injury. In this paper, some harmful agents, level of activity and its mechanism of action. Their knowledge is essential to settle the therapeutic approach to aplied appropriate treatment to each tendon injury (AU)

Conceptos actuales de la fisiopatología de las tendinopatías. Ingeniería tisular / Current concepts of the pathophysiology of tendinopathies. Tissue engineering

La tendinopatía es una lesión frecuente que se produce durante la práctica deportiva.El reparto desigual de la carga de trabajo a lo largo del tendón produce roturas heterogéneas en extensión y distribución. Estas roturas ponen en marcha procesos de reparación defectuosos que producen un tendón degenerado con alteración estructural y de la respuesta funcional al ejercicio.En este trabajo se estudian y analizan los distintos factores predisponentes, mecanismos de acción de los agentes químicos y celulares implicados en la fisiopatología de la tendinopatías.Por otra parte, se analizan los componentes básicos (soporte, células y sustancias químicas) que se usan para la ingeniería tisular. Las posibilidades actuales de uso de los componentes básicos y sus interrelaciones, y el nivel actual de desarrollo(AU)

Tendinopathy is a common condition that occurs while practising sport.The unequal distribution of the work load throughout the tendon causes heterogeneous ruptures in extension and distribution. These ruptures start defective repair processes that produce a degenerated tendon with a change in structure and functional response to exercise.In this article the different predisposing factors are study, along with the mechanisms of action of the chemical and cellular agents involved in the physiology of tendinopathies.The basic components (support, cells and chemical substances) that are used for tissue engineering are also analysed, as well as the current possibilities of using the basic components, the inter-relationships between them and the current level of execution(AU)

Epiphyseal femoral tumour resection under intraosseous endoscopic control.

We have resected 4 benign cystic femoral head tumours under intraosseous endoscopic control. The resections were completely extraarticular through a tunnel made in the femoral neck from the lateral cortex. The procedures were assessed endoscopically with the help of a standard arthroscope. With a minimum follow-up of 1 year (range 1-16 years), there were no recurrences. Mean age at time of surgery was 23 years (range 19-26 years). Only 1 (fibrous defect) needed prophylactic osteosynthesis with a dynamic hip screw. The lateral approach through a bone tunnel allows preservation of the joint. The creation of a wider tunnel (10-15 mm) avoids the need for an irrigation system, without debilitating the bone structure, and simplifies the surgical procedure.