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During the past few decades, surgical techniques for anterior cruciate ligament (ACL) reconstruction have been developing significantly. To date, studies have shown that after ACL reconstruction, rotational stability has a greater impact on the patient's satisfaction, functional scores, and return to sports than translational stability. Although challenged by many authors in the literature, biomechanical studies on the anterolateral ligament (ALL) of the knee and clinical studies regarding ALL reconstruction have been revealing promising results. Thus, the potentially significant role of the ALL in biomechanical load sharing and improving rotational control of the knee has led to the development of various reconstruction techniques whose goal is to achieve simplicity and yield the best results possible. Guided by this idea, we have developed a modified ACL-ALL reconstruction surgical technique. In this article, our simple, bone-saving, anatomic technique to reconstruct both the ACL and ALL using hamstring tendon autograft is described., Technique Video Video 1 On the Graft Prep Station Base (Arthrex), the harvested semitendinosus tendon is marked every 8 cm and tripled over a TightRope on the tibial side, ensuring a graft length of 8 cm. The most distal suture (No. 2-0 Vicryl) is placed to stabilize the tripled semitendinosus graft and secure the length. The gracilis tendon is put inside the tripled semitendinosus graft, and the whole graft is then tagged with multiple sutures (No. 2-0 Vicryl) to secure the gracilis position and to tubularize the graft. A No. 2 FiberWire is placed on the femoral end of the anterior cruciate ligament (ACL) graft by going around and through the tendons to ensure secure further graft manipulation. The ACL graft is marked 3 cm from both the femoral and tibial sides, representing parts of the graft that will be placed inside the bone tunnels. An ACL graft consisting of 3 parts semitendinosus and 1 part gracilis is obtained, with a diameter of 8 to 10 mm and length of 8 cm. With the patient in the supine position and the left knee in 90° of flexion and in a leg holder, 3 bony landmarks are marked on the patient's left knee: the lateral epicondyle, the Gerdy tubercle, and the head of the fibula. Two convergent bony tunnels are drilled in the proximal part of the left tibia with a 4.5-mm drill bit, separated by roughly 2 cm and approximately 1 cm distal to the joint line. A suture (No. 2 Vicryl) is then passed through the tunnels in a retroverted fashion to create a loop for further anterolateral ligament (ALL) graft (gracilis tendon) passage. The tibial guidewire (outside-in jig) is placed 55° from the external medial tibial cortex into the ACL remnant. Subsequent reaming with the retro-drill is performed for 35 mm according to the previously measured ACL graft size, with preservation of the ACL remnant synovial cover and tibial attachment. A 2- to 3-cm incision is made along the lateral aspect of the thigh, extending proximal from the lateral epicondyle. A Kirschner wire is used to mark the femoral epicondyle. A guide is introduced through the anteromedial portal. The tip of the guide is anchored at the ACL femoral insertion. The guide sleeve is pushed onto the lateral cortex through the femoral stab incision underneath the iliotibial band (ITB) and into the incision made longitudinally through the ITB fibers to position a drill for femoral tunnel drilling roughly 1 cm proximal and 8 mm posterior to the Kirschner wire. Then, subsequent femoral bone drilling is performed to the appropriate measured ACL size. By use of a suture, the TightRope and graft are passed through the longitudinal incision of the ITB and the ACL femoral tunnel to the distal 3-cm mark inside the tibial tunnel. To ensure the exact length of the graft in the tibial bone tunnel (distal demarcation), tension on the graft from the femoral side is used and the correct graft and demarcation position is monitored arthroscopically. Subsequently, the TightRope is tightened on the tibial side and secured with the knee at 90° of flexion. The knee is then placed at 20° of flexion, and the femoral part of the ACL graft is tightened and secured with an outside-in bioabsorbable interference screw. With the use of a grasper or a shuttle suture, the suture tied to the gracilis is shuttled under the ITB through the incision made longitudinally through the ITB fibers and then through the skin incision made for the posterior end of the tibial bone tunnel. The ALL graft is shuttled through the tibial bone tunnel from posterior to anterior, using the previously passed suture loop (No. 2 Vicryl). The gracilis graft is brought back proximally again under the ITB and tied with FiberWire from the femoral end of the ACL graft with the patient's left knee in full extension and neutral rotation.

The treatment of cartilage defect remains a challenging issue in clinical practice. Chitosan- based materials have been recognized as a suitable microenvironment for chondrocyte adhesion, proliferation and differentiation forming articular cartilage. The use of nasal chondrocytes to culture articular cartilage on an appropriate scaffold emerged as a promising novel strategy for cartilage regeneration. Beside excellent properties, chitosan lacks in biological activity, such as RGD-sequences. In this work, we have prepared pure and protein- modified chitosan scaffolds of different deacetylation degree and molecular weight as platforms for the culture of sheep nasal chondrocytes. Fibronectin (FN) was chosen as an adhesive protein for the improvement of chitosan bioactivity. Prepared scaffolds were characterised in terms of microstructure, physical and biodegradation properties, while FN interactions with different chitosans were investigated through adsorption–desorption studies. The results indicated faster enzymatic degradation of chitosan scaffolds with lower deacetylation degree, while better FN interactions with material were achieved on chitosan with higher number of amine groups. Histological and immunohistochemical analysis of in vitro engineered cartilage grafts showed presence of hyaline cartilage produced by nasal chondrocytes.

Objective Nasal septal pathologies requiring surgical intervention are common in the population. Additionally, nasal chondrocytes are becoming an important cell source in cartilage tissue engineering strategies for the repair of articular cartilage lesions. These procedures damage the nasal septal cartilage whose healing potential is limited due to its avascular, aneural, and alymphatic nature. Despite the high incidence of various surgical interventions that affect septum cartilage, limited nasal cartilage repair characterizations have been performed to date. Methods To evaluate the healing of the nasal septum cartilage perforation, a septal biopsy was performed in 14 sheep. Two and 6 months later, the tissue formed on the place of perforation was explanted and compared with the native tissue. Tissue morphology, protein and gene expression of explanted tissue was determined using histological, immunohistochemical and real-time quantitative polymerase chain reaction analysis. Results Tissue formed on the defect site, 2 and 6 months after the biopsy was characterized as mostly connective tissue with the presence of fibroblastic cells. This newly formed tissue contained no glycosaminoglycans and collagen type II but was positively stained for collagen type I. Cartilage-specific genes COL2, AGG, and COMP were significantly decreased in 2- and 6-month samples compared with the native nasal cartilage. Levels of COL1, COL4, and CRABP1 genes specific for perichondrium and connective tissue were higher in both test group samples in comparison with native cartilage. Conclusions Newly formed tissue was not cartilage but rather fibrous tissue suggesting the role of perichondrium and mucosa in tissue repair after nasal septum injury.

Background Matrix metalloproteinases (MMPs) play an important role in matrix remodelling, as well as in tendon integrity. Due to overuse, athletes often develop chronic tendinopathies. If not treated, they lead to severe impairment, even complete tendon ruptures. Aim The main purpose of this study was to investigate whether three functional polymorphisms within the MMP3 gene are associated with increased risk of developing tendinopathies in high-level Croatian athletes. Methods We have recruited one hundred fifty- five (63 high-level athletes with diagnosed tendinopathies and 92 asymptomatic controls) unrelated Caucasians for this case- control genetic study. All participants were genotyped for three single nucleotide polymorphisms (SNP) within the MMP3 gene: rs591058 C/T, rs650108 A/G and rs679620 G/A using the pyrosequencing method. Results The MMP3 rs650108 GG (P = 0.0074) and rs679620 AA (P = 0.0119) genotypes were significantly over-represented in cases compared with controls, while rs591058 TT (P = 0.0759), as well as haplotype variant T - G - A (P = 0.06), implicated that there is an indication of predisposition for tendinopathies. Conclusion These results support association between functional variants within the MMP3 gene and the risk of tendinopathies in high-level athletes. Further research is needed to replicate these results in a larger population.

The main goal of this study was the formation of bone tissue using dexamethasone (DEX)-loaded [COCH3]-RADARADARADARADA-[CONH2] (RADA 16-I) scaffold that has the ability to release optimal DEX concentration under perfusion force. Bone-marrow samples were collected from three patients during a hip arthroplasty. Human mesenchymal stem cells (hMSCs) were isolated and propagated in vitro in order to be seeded on scaffolds made of DEX-loaded RADA 16-I hydrogel in a perfusion bioreactor. DEX concentrations were as follows: 4 &times, 10&minus, 3, 4 &times, 4 and 4 &times, 5 M. After 21 days in a perfusion bioreactor, tissue was analyzed by scanning electron microscopy (SEM) and histology. Markers of osteogenic differentiation were quantified by real-time polymerase chain reaction (RT-PCR) and immunocytochemistry. Minerals were quantified and detected by the von Kossa method. In addition, DEX release from the scaffold in a perfusion bioreactor was assessed. The osteoblast differentiation was confirmed by the expression analysis of osteoblast-related genes (alkaline phosphatase (ALP), collagen I (COL1A1) and osteocalcin (OC). The hematoxylin/eosin staining confirmed the presence of cells and connective tissue, while SEM revealed morphological characteristics of cells, extracellular matrix and minerals&mdash, three main components of mature bone tissue. Immunocytochemical detection of collagen I is in concordance with given results, supporting the conclusion that scaffold with DEX concentration of 4 &times, 4 M has the optimal engineered tissue morphology. The best-engineered bone tissue is produced on scaffold loaded with 4 &times, 4 M DEX with a perfusion rate of 0.1 mL/min for 21 days. Differentiation of hMSCs on DEX-loaded RADA 16-I scaffold under perfusion force has a high potential for application in regenerative orthopedics.

The aim of this study is to examine the capacity of muscle tissue preserved on hamstring tendons forming candy-stripe grafts in order to improve tendon to bone ingrowth and ligamentization. We hypothesized that muscle tissue does possess a stem cell population that could enhance the healing process of the ACL graft when preserved on the tendons. Human samples from gracilis and semitendinosus muscles were collected during ACL surgery from ten patients and from these tissue samples human muscle-derived stem cells and tendon- derived stem cells were isolated and propagated. Both stem cell populations were in- vitro differentiated into osteogenic lineage. Alkaline phosphatase activity was determined at days zero and 14 of the osteogenic induction and von Kossa staining to assess mineralization of the cultures. Total RNA was collected from osteoblast cultures and real time quantitative PCR was performed. Western-blot for osteocalcin and collagen type I followed protein isolation. Immunofluorescence double labeling of pericytes in muscle and tendon tissue was performed. Mesenchymal stem cells from muscle and tendon tissue were isolated and expanded in cell culture. More time was needed to grow the tendon derived culture compared to muscle derived culture. Muscle derived stem cells exhibited more alkaline phosphatase actvity compared to tendon derived stem cells, whereas tendon derived stem cells formed more mineralized nodules after 14 days of osteoinduction. Muscle derived stem cells exhibited higher expression levels of bone sialoprotein, and tendon derived stem cells showed higher expression of dental-matrix- protein 1 and osteocalcin. Immunofluorescent staining against pericytes indicated that they are more abundant in muscle tissue. These results indicate that muscle tissue is a better source of stem cells than tendon tissue. Achievement of this study is proof that there is vast innate capacity of muscle tissue for enhancement of bone-tendon integration and ligamentization of ACL hamstring grafts and consequently muscle tissue should not be treated as waste after harvesting.

Development of artificial materials for the facilitation of cartilage regeneration remains an important challenge in orthopedic practice. Our study investigates the potential for neocartilage formation within a synthetic polyester scaffold based on the polymerization of high internal phase emulsions. The fabrication of polyHIPE polymer (PHP) was specifically tailored to produce a highly porous (85%) structure with the primary pore size in the range of 50–170 μm for cartilage tissue engineering. The resulting PHP scaffold was proven biocompatible with human articular chondrocytes and viable cells were observed within the materials as evaluated using the Live/Dead assay and histological analysis. Chondrocytes with round nuclei were organized into multicellular layers on the PHP surface and were observed to grow approximately 300 μm into the scaffold interior. The accumulation of collagen type 2 was detected using immunohistochemistry and chondrogenic specific genes were expressed with favorable collagen type 2 to 1 ratio. In addition, PHP samples are biodegradable and their baseline mechanical properties are similar to those of native cartilage, which enhance chondrocyte cell growth and proliferation.

AIM: Determine the levels of expression of pluripotency genes OCT-4 and SOX-2 before and after osteogenic differentiation of human mesenchymal stem cells (hMSCs).METHODS: Human MSCs were derived from the bone marrow and differentiated into osteoblasts. The analyses were performed on days 0 and 14 of the cell culture. In vitro differentiation was evaluated due to bone markers – alkaline phosphatase (AP) activity and the messenger RNA (mRNA) expression of AP and bone sialoprotein (BSP). The OCT-4 and SOX-2 expression was evaluated at mRNA level by real-time qPCR and at protein level by immunocytochemistry.RESULTS: In vitro cultures on day 14 showed an increase in AP activity and upregulation of AP and BSP gene expression. OCT-4 and SOX-2 in undifferentiated hMSCs on day 0 is detectable and very low compared to tumor cell lines as a positive control. Immunocytochemistry detected OCT-4 in the cell nuclei prior (day 0) and post differentiation (day 14). On the same time points, cultures were negative for SOX-2 protein.CONCLUSION: Messenger RNA for pluripotency markers OCT-4 and SOX-2 isolated from hMSCs was less present, while OCT-4 protein was detected in cell nuclei prior and post differentiation into osteoblast lineage.

Usual clinical practice for autologous chondrocyte implantation (ACI) involves harvesting of articular cartilage from non- weightbearing part of the joint. Although effective, it induces additional trauma to the joint and additional surgical procedure with anesthesia. Alternative source of chondrocytes would substantially decrease morbidity and duration of the procedure, as well as the cost of the procedure. Nasal chondrocytes could be viable alternative for ACI in human patients. Before using it in clinical settings, it is necessary to test this hypothesis on translational (large animal) model. Designed model was chronic, full-thickness cartilage defect placed on lateral and medial femoral condyles in sheep. The protocol included two surgical procedures. First procedure was to create two partial-thickness defects, 4 mm in diameter on the lateral and medial femoral condyle with a standard mosaicplasty instruments used in human orthopaedic surgery. Biopsy of nasal septum cartilage was also performed with skin biopsy puncher, 8 mm in diameter. Cartilage samples from both origins were used for production of autologous tissue grafts. Chondrocytes were isolated, seeded on biphasic collagen-hydroxiapatite scaffolds, and cultured in automated bioreactor for 5 weeks. Engineered tissue was then implanted in condyle defects during second procedure. First, 4 mm partial-thickness defects were converted to osteochondral defects 6, 5 mm in diameter and 5 mm deep. Then engineered cartilage tissue was implanted. There were four study groups. Autologous tissue grafts, engineered from scaffold and nasal septum chondrocytes were implanted in the experimental group of animals. One group was implanted with autologous tissue grafts engineered from scaffold and articular chondrocytes. In one group cell free scaffolds were implanted while last group served as negative control in which only conversion of defect was performed, but it was left untreated. Animals were sacrificed and tissue analysis was performed at three different time points: 6 weeks, 3 months and 12 months after the implantation. Tissue analysis included macroscopic, microscopic and molecular evaluation. ICRS score was used to evaluate macroscopic apperance of the repair tissue. Microscopic analysis included different stains (hematoxylin-eosin, safranin O, picrosirius) and immunohistochemistry (collagen I, II and aggrecan) to determine the type of repair tissue, organization of collagen and integration. Semi-quantitative data of morphology were obtained with histological score ICRS II. ELISA and DMMB assays were performed to quantify the amount of collagen I, II and glycosaminoglycans in repair tissue. Results confirmed the feasibility of production of autologous cartilage tissue grafts from nasal septum chondrocyte for treatment of condyle cartilage defects. Furthermore, nasal chondrocyte grafts showed promising results in restoration of damaged articular cartilage. The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n°278807.

Bone defects, including normal fracture healing as well as healing prob- lems represent a global health problem. The need for better treatment of bone defects is one of the central issues of tissue engineering and regenerative medicine. Regenerative orthopedics has several approaches – activation of endogenous stem cells, stem cell therapy and tissue engineering. Development of new treatments is mainly focused on the tissue engineering strategies that include stem cells, bioactive signals and appropriate scaffold support. The aim of this review is to describe a variety of stem cells that have an ability to become bone cells and therefore are of central importance for bone tissue engineering. Several cell types have been proposed as starting material - embryonic stem cells, induced pluripotent stem cells and adult stem cells. Due to ethical and safety issues, embryonic and induced pluripotent stem cells may be more suitable for studying human development and tissue for- mation under diverse experimental conditions, and represent an excellent base for understanding human diseases and development of innovative therapeutic solutions. Among adult stem cells, mesenchymal stem cells are the most suitable for bone tissue engineering. They can be isolated from variety of mesenchymal tissues and can differentiate into osteoblasts when given appropriate mechanical support and osteoinductive signal. The near future of bone healing and regeneration is closely related to advances in tissue engineering. The optimization of protocols of bone graft production using autologous mesenchymal stem cells loaded on appropriate scaffolds, exposed to osteogenic inducers and mechanical force in bioreactor, should be able to solve the current limitations in managing bone injuries.

The purpose of this paper is to review current developments in bone tissue engineering, with special focus on the promising role of nanobiotechnology. This unique fusion between nanotechnology and biotechnology offers unprecedented possibilities in studying and modulating biological processes on a molecular and atomic scale. First we discuss the multiscale hierarchical structure of bone and its implication on the design of new scaffolds and delivery systems. Then we briefly present different types of nanostructured scaffolds, and finally we conclude with nanoparticle delivery systems and their potential use in promoting bone regeneration. This review is not meant to be exhaustive and comprehensive, but aims to highlight concepts and key advances in the field of nanobiotechnology and bone regeneration.

Osteogenesis imperfecta or brittle bone disease, a heritable disorder of connective tissue, is the most common of the inherited disorders primarily affecting bone. There are approximately 400 individuals with OI in Croatia alone. It is estimated that twice that number is present, represented by individuals with mild OI in whom the diagnosis has not been made. Due to the relatively low number of patients in the general population, treating physicians have limited experience with this disease, either with children or adults. The basis of this disease in European populations is mostly the result of defects in the structure or processing of collagen type I, an important protein of the extracellular matrix of many tissues. Presently, molecular defects in 16 different genes have been discovered to result in at least one type of OI of which 14 are not COL1 mutation loci. Although fractures occurring with no injury or minor injury are the hallmark of OI, other non-mineralized tissues can be affected as well and the pathological changes can be present in skin, tendons, eyes, teeth and blood vessels. Clinical manifestations are very heterogeneous and numerous signs and symptoms such as blue sclera, deafness, abnormal teeth development, joint hypermobility, increased risk of hernias, capillary fragility, aneurysms etc. Although there is no cure for this disease, there are specific therapies that can reduce the pain and complications associated with OI. The purpose of this review is to provide a brief overview of the molecular basis of this disease, describe clinical presentations, as well as to present orthopaedic therapeutic modalities for the patients with OI.

Stress fractures are common overuse injuries of the bone that are most often seen in athletes and military personnel. These types of injuries seem to be commonly missed or delayed in diagnosis. Physicians should consider the possibility of such an injury while determining the diagnosis of a long-lasting foot pain. The aim of this paper was to report an isolated stress fracture of the lateral cuneiform bone. A review of the literature failed to find a similar case. (J Am Podiatr Med Assoc 103(4): 337–339, 2013)

Clinical management of delayed healing or nonunion of long bone fractures and segmental bone defects poses a substantial orthopaedic challenge. Surgical advances and bone tissue engineering are providing new avenues to stimulate bone growth in cases of bone loss and nonunion. The reamer-irrigator-aspirator (RIA) device allows surgeons to aspirate the medullary contents of long bones and use the progenitor-rich “flow-through” fraction in autologous bone grafting. Dexamethasone (DEX) is a synthetic steroid that has been shown to induce osteoblastic differentiation. A series of 13 patients treated with RIA bone grafting enhanced with DEX for nonunion or segmental defect was examined retrospectively to assess the quality of bony union and clinical outcomes. Despite the initial poor prognoses, promising results were achieved using this technique ; and given the complexity of these cases the observed success is of great value and warrants controlled study into both standardisation of the procedure and concentration of the grafting material.

Orthopedic surgery is going through a serious paradigm shift ; instead of simply replacing damaged tissues with prosthetic or allograft material, the aim is to regenerate them. This endeavor has generated the field of regenerative orthopaedics, an increasingly expanding area of research with hopes of providing new and better treatments for diseases and injuries affecting the musculoskeletal system. As part of this process, we are witnessing a substantial accumulation of new cellular and molecular insights into connective tissue function, coupled with emerging new concepts in stem cell biology and scaffolding technologies. Indeed, any successful strategy to regenerate musculoskeletal tissues can be portrayed as an intricate interplay between the three main constituents of the regenerative system: cells, environment and scaffolds. This review is not meant to be exhaustive and comprehensive, but aims to highlight concepts and key advances in the field of regenerative orthopaedics and tissue engineering, as well as to present current possibilities for clinical translation.

U posljednja tri destljeća znatno se povećao broj žena koje se natječu u sportskim aktivnostima na svim razinama. Povećano sudjelovanje žena je dovelo i do povećanog rizika od ozljeda, bilo akutno-traumatskih bilo onih uzrokovanih prenaprezanjem. Ozljede izazvane prenaprezanjem definiraju se kao neravnoteža izazvana preintenzivnim treniranjem bez odgovarajućeg odmora, što s vremenom dovodi do prestanka rada mehanizama za reparaciju tkiva. Ovaj članak daje pregled najčešćih ozljeda izazvanih prenaprezanjem kod sportašica , s posebnim naglaskom na anatomske, fiziološke i psihološke razlike među spolovima., The last three decades have witnessed a tremendous increase in female sports participation at all levels. However, increased sports participation of female athletes has also increased the incidence of sport-related injuries, which can be either acute trauma or overuse injuries. Overuse injuries may be defined as an imbalance caused by overly intensive training and inadequate recovery, which subsequently leads to a breakdown in tissue reparative mechanisms. This article will review the most frequent overuse injuries in female athletes in the context of anatomical, physiological, and psychological differences between genders. The ancient Greeks barred women from participating at the ancient Olympics, even as spectators (1). Baron Pierre de Coubertin, the man credited for the birth of the modern Olympics, regarded women’s taking part in sports as being “against the laws of nature.” To cite his words: “Olympics are solemn and periodic exaltation of male athleticism, with internationalism as a base, loyalty as a means for its setting and female applause as a reward” (2). As a result of this attitude, women did not participate at the first modern Olympic games in Athens in 1896. However, a century later at the same place – during the 2004 Olympics, 4329 women from all over the world competed in the majority of 300 official events. Nowadays, taking part in sports is seen a positive experience for women, since it improves physical fitness, enhances self-esteem, and contributes to better physical and mental health. Apart from professional sport, there has also been a dramatic increase in women’s sports participation on recreational and amateur level.

Prije dvadesetak godina u Klinici za ortopediju ugrađivali smo umjetne ligamente, i to tip proteze ligamenta Gore-Tex (razgranati polytetrafluoroethylen) kao postupak spašavanja nestabilnih koljena. U 13 bolesnika koristili smo protezu ligamenta Gore-Tex za rekonstrukciju stražnje ukrižene sveze (engl. posterior cruciate ligament PCL). U pacijenta F. K. imali smo priliku nakon 20 godina od izvršene rekonstrukcije PCL-a izvršiti kliničku, artroskopsku, magnetskorezonantsku (MRI) i patohistološku evaluaciju. Zbog artrotskih promjena u koljenu u bolesnika je bilo potrebno izvršiti artroskopsku toaletu koljena. Tom prilikom se izvršila i artroskopska evaluacija ugradene proteze ligamenta Gore-Tex te se napravila biopsija za patohistološku analizu (PHD). Prethodno je napravljen MRI koji je pokazivao uredan kontinuitet i volumen PCLa uz uznapredovale artrotske promjene koljena. Nalaz MRI bio je sukladan kliničkom nalazu koji je pokazivao dobru stabilnost koljena. Tijekom artroskopije uz standardne ulaze koristio se i posteromedijalni ulaz radi boljeg prikazivanja PCL-a. Artroskopija je pokazala da je proteza ligamenta Gore-Tex u cijelosti obložena zadebljanom sinovijalnom membranom odnosno fibrozom, a kada se na jednom mjestu odstranila sinovijalna membrana vidjele su se karakteristične polytetrafluoroethylenske niti u kontinuitetu. Probatornom sondom dokazao se kontinuitet PCL-a, a potom se uzelo nekoliko komadića ovojnice umjetnog ligamenta za PHD. Isto tako uzelo se i nekoliko komadića sinovijalne membrane iz drugih dijelova koljena. Patohistološki nalaz je pokazao da nema upalne reakcije u sinovijalnoj membrani koljena, a u ovojnici proteze ligamenta Gore-Tex našlo se zrelo vezivno tkivo s prisustvom multinuklearnih orijaških stanica uz fragmente stranog polarizirajuceg materijala. Ovaj prikaz slučaja pokazuje dobru biokompaktibilnost te dobru stabilnost koljena nakon 20 godina od ugradnje proteze ligamenta Gore-Tex u bolesnika s izrazito nestabilnim koljenom. Zanimljivo je napomenuti da nije došlo do propadanja niti polytetrafluoroethylena., Twenty years ago the Gore-Tex expanded polytetrafluoroethylene (PTFE) prosthetic ligament was used as feasible salvage procedure in patients with failed, multiply operated knees, or knees with gross instability. At the Department of Orthopaedic Surgery we operated 13 patients and replaced the posterior cruciate ligament (PCL) with the Gore-Tex prosthetic ligament. Recently we had opportunity to evaluate clinical, arthroscopic, magnetic resonance imagining (MRI) and patohystologic (PH) findings in patient F. K. twenty years after the reconstruction. Due to osteoarthritic changes arthroscopic toilette of the knee was performed. On that occasion arthroscopic evaluation and biopsies for microscopic examination were carried out. MRI performed prior to arthroscopy revealed tidy continuity and volume of PCL with advanced arthritic changes of knee. MRI findings were consistent to clinical findings of good knee stability. Arthroscopy revealed the Gore-Tex prosthetic ligament completely coated with thicken synovial membrane i.e. fibrosis. Partial removal of the synovial membrane showed continuity of characteristic PTFE strands. The continuity of PCL was established by the probe. After that, few pieces of synovial membrane from sheath of PCL and from other parts of synovial membrane of the knee were taken. One PTFP strand of artificial PCL was collected as well. Patohystological findings clearly excluded inflammatory reaction in synovial membrane of the knee. Furthermore, synovial membrane of Gore-Tex prosthetic ligament sheath was found to contain mature fibrotic tissue with multinuclear giant cells and fragments of foreign polarizing material. This case report demonstrated good biocompatibility and good knee stability twenty years after replacement of the PCL with the Gore-Tex prosthetic ligament in patient with gross instability. It is interesting to mention that there was no deterioration of PTFE strands.

The aim of this paper is to report on three cases of symptomatic osteochondritis dissecans of the humeral capitellum in adolescent gymnasts, two females and one male. In all the cases arthroscopic surgery was performed. During arthroscopy, loose osteochondral fragments were removed, the defect was debrided and microfractures were performed. All the three patients regained the full range of motion of the affected elbow, and returned to the high-level gymnastics within a period of 5 months. At 12 months follow-up, all the three patients remained symptomless and were participating in high-level gymnastics. A combination of arthroscopy and the microfracture technique is a reliable method with excellent short-term results in the treatment of the osteochondritis dissecans of the elbow.

The authors report a case of a 21-year-old woman with osteoid osteoma of the talar neck that was treated with arthroscopic resection. The nidus was removed in one piece with grasping forceps, and histopathologic findings confirmed the preoperative diagnosis of osteoid osteoma. Postoperatively, the patient was immediately relieved of ankle pain and there was no recurrence at the 1-year follow-up. If possible, the nidus should be removed without the use of a motorized instrument to ensure the correct histolologic diagnosis.