[New Anterior Cruciate Ligament Reconstrucion Using Harmstring Tendon Grafts - Clinical Part]. / Nová metoda rekonstrukce predního zkrízeného vazu kolenního kloubu pomocí hamstringu ­ klinická cást.

PURPOSE OF THE STUDY The authors present the clinical use of the new instrumentation set for the anterior cruciate ligament (ACL) reconstruction using the hamstring tendons (HS). The positionning of the femoral tunnel and the fixation of the graft play an important role for the results of the surgery. The aim of the study was to confirm the proposed surgical technique and the methods of the graft fixation, especially from the point of view of the clinical midterm results at the evaluation up to eight years after the surgery. MATERIAL AND METHODS The clinical evaluation comprises 58 patients operated from 2007 to 2014 using the new instrumentation set. There were 9 men and 49 women included in the sample. The mean age was 34.6 years (range 18 - 58 yrs), namely 36.7 in women and 32.4 years in men. The evaluation was performed pre-opeatively and at 3 and 6 months, 1, 3, 5 and 8 years post-operatively. All the patients were followed based on the same criteria - clinical range of motion (ROM), stability of the knee - instrumentation Lachman test utilizing Rolimeter, subjective IKDC score and pain VAS scale for the harvesting site. The ocurrence and the rate of post-operative complications were monitored. RESULTS The integration and the ingrowth of the graft were achieved in all cases, the full ROM was gained as well, no pathological instability was observed. The fixation of the HS graft in the bone was confirmed by post-op X ray at 3 months after the surgery. The clinical evaluation showed the following mean differences in the pre-op and final post-op findings. The average preoperative laxity using the Lachmann test was 9.7 mm (range 6-12 mm), at 3 months 1.8 mm (1.4-2.1 mm), at 6 months 1.6 mm (1.2 - 2.2 mm), at 1 year 1.6 mm (1.1-2.3 mm), at 3 years the stability was 1.7 mm (1.2 mm-2.4 mm), at 5 years 2.3 mm (1.2-3.6 mm) and at 8 years after surgery it was 2.5 mm (1.2-3.9 mm). None of the patitents included in the study showed pathological instability that would be considered an indication for revision. In the evaluation of the subjective IKDC score, the pre-operative average was 56, with the range of 42-66, at 3 months post-operatively 79 (69-85), at 6 months 88 (74-92), at 1 year 95 (88-100), at 3 years 96 (89-100), at 5 years 94 (87-100), and at 8 years 92 (84-98). No severe complications were observed. CONCLUSIONS The method provided sufficient post-operative stability of the knee joint. Fixation of the femoral screw satisfied the demands laid on it. Regarding the pain perception, the method was considered positive, the level of pain involved in the procedure was low. No severe complications or technical mistakes occurred during the surgical procedures. The new instrumentation set developed for the ACL reconstruction offers an easy technique and comfortof use. Key words:anterior cruciate ligament, reconstruction, hamstrings, knee arthroscopy, instrumentation set.

[New Technique of Anterior Cruciate Ligament Reconstruction Using Hamstrings - the Surgical Instrumentation Set]. / Nová metoda rekonstrukce predního zkrízeného vazu kolenního kloubu pomocí hamstringu ­ operacní instrumentárium.

PURPOSE OF THE STUDY The success rate of the anterior cruciate ligament (ACL) reconstruction depends on the fixation of the graft, the surgical technique and, of course, on the experience of the operating surgeon. The authors present the development of the construction of the new instrumentation set designed to manage the ACL lesions using the hamstring (HS) tendons. The study is divided into two parts, of which part one focuses on construction, methods and work with new instruments, while part two presents the outcomes of the surgery. MATERIAL AND METHODS Fixation of hamstring grafts depends, contrary to the union of bone blocks in the Bone-Tendon-Bone (BTB) graft and the bone tunnel, on the method of tendon graft fixation and compression inside the bone tunnel. The instrumentation set for ACL reconstruction is designed to be used for hamstring tendons (semitendon and gracilis) forming four strands of the prepared graft. The system was designed as the fixation of the graft using the femoral screw with eyelet and a press-fit fixation using a metal interference screw in tibia. The easiest and fastest option has proven to be the pulling of the screw with eyelet through the tibial tunnel and intra-articular space to the femoral canal, where fixation by screwing in is done. The exact position of the inserted screw is verified by the measuring gauge. The screw is pulled in by the long version of the femoral screwdriver and Kirschner wire passing through the middle of the screw with eyelet. The advantage of this system consists in the subsequent insertion of the interference screw by the same wire, which guarantees its exact positioning in the centre between the individual strands of the graft (thanks to the specific way of ligament preparation). The possibility of later tensioning of the graft by tightening the femoral screw is another advantage. DISCUSSION Compared to other methods using the HS tendons, the advantages of the described operative technique consist in the simplicity of the used instrumentation procedure. The technique of graft fixation inside the femoral canal is not suitable for bioabsorbable materials. It is offset by the fixation stability and the possibility of final graft tensioning. CONCLUSIONS The newly developed instrumentation set for ACL reconstruction is fit for purpose, easy as to the surgical technique, and it guarantees the logical sequence of surgical steps reducing surgical errors to minimum. The instrumentation set is userfriendly, easy to handle and, once the operating surgeon masters the surgical procedure, it allows to reduce the duration of the surgery to approximately 30 minutes. There were no major complications or technical errors reported during the surgical procedures using these instrumentation set. Key words: anterior cruciate ligament - reconstruction - instrumentation set - knee arthroscopy.

[Structural Damage to the Hamstring Graft due to Interaction with Fixation Material and its Effect on Biomechanical Properties of ACL Reconstruction]. / Strukturální zmeny stepu z hamstringu zpusobené fixacním materiálem a jejich vliv na biomechanické vlastnosti náhrady LCA.

PURPOSE OF THE STUDY Hamstring grafts are commonly used for ACL reconstruction. The purpose of our study is to determine the effects of the suspension fixation compared to graft cross-pinning transfixation, and the effect(s) of structural damage during the preparation of the graft on biomechanical properties of the graft. MATERIAL AND METHODS The design of the study is a cadaveric biomechanical laboratory study. 38 fresh-frozen human hamstring specimens from 19 cadaveric donors were used. The grafts were tested for their loading properties. One half of each specimen was suspended over a 3.3mm pin, the other half was cross-pinned by a 3.3mm pin to simulate the graft cross-pinning technique. Single impact testing was performed and the failure force, elongation and acceleration/deceleration of each graft was recorded and the loading force vs. elongation of the graft specimens was calculated. Results for suspended and cross-pinned grafts were analysed using ANOVA method, comparing the grafts from each donor. RESULTS The ultimate strength of a double-strand gracilis graft was 1287 ± 134 N when suspended over a pin, the strength of a cross-pinned graft was 833 ± 111 N. For double-strand semitendinosus grafts the strengths were 1883 ± 198 and 997 ± 234 N, respectively. Thus, the failure load for the cross-pinning method is only 64.7% or 52.9% for the suspension method. DISCUSSION Structural damage to the graft significantly reduces the graft strength. Also, extensive suturing during preparation of the graft reduces its strength. CONCLUSIONS Fixation methods that do not interfere with the graft's structure should be used to reduce the risk of graft failure. Key words: ACL reconstruction, hamstring graft, biomechanical testing.

Comparison of the cellular composition of two different chondrocyte-seeded biomaterials and the results of their transplantation in humans.

Our study compares the histological and immunohistochemical cellular composition of two different chondrocyte-seeded biomaterials and the results of their transplantation. Our study cohort included 21 patients, comprising 19 men and two women with a mean age of 32 years, who were affected by single chondral lesions of the femoral condyles. These patients were enrolled in our study and treated with arthroscopic implantation of the tissue Hyalograft C and/or Brno culture. Brno culture bioengineered with a fibrin-based scaffold contains round cells showing features of differentiated chondrocytes expressing S-100 protein and α-smooth muscle actin. In contrast, in the case of Hyalograft C, the scaffold was made up of a fibrillar network composed of biomaterial fibres of the esters of hyaluronic acid and cells resembling fibroblasts and myofibroblasts and expressing only α-smooth muscle actin. The average size of the defects was 2.5 cm2. Patients were evaluated using the standardized guidelines of the International Knee Documentation Committee. During the comparison of bioptic samples obtained from both patient cohorts, we did not observe any important differences in the histological makeup of the newly formed cartilage. The histological analysis of these two groups of homogeneous patients shows that this bioengineered approach, under proper indications, may offer favourable and stable clinical results over time, in spite of the different matrix and cellular composition of the two transplants used.

[Method of functional treatment of distal radius fractures]. / Vyuzití funkcní lécby v terapii zlomenin distálního radia.

PURPOSE OF THE STUDY To present the method of functional treatment of distal radius fractures, and to evaluate its results in a group of 57 patients. MATERIAL The method described here was used to treat a Colles fracture in 57 patients between 2001 and 2005. The average age of patients at the time of injury was 62 years (range, 19 to 82). The minimal interval between the end of treatment and the evaluation of the patient group was one year. METHODS The presented method is based on the principles of functional treatment of wrist fractures, as advocated by Sarmiento et al. When the patient has been indicated for this treatment, the arm is immobilised in a classic rigid cast. This cast is changed three weeks after application for a cast permitting full palmar flexion and full ulnar deviation. The cast is removed when callus formation is detected and the fracture site is free of pain. During this treatment, much attention is paid to skin condition, with an emphasis on preventing the development of Sudecks algoneurodystrophy. RESULTS This method of functional treatment resulted in complete fracture healing in all patients. None of them required hospitalization. The total period of immobilization was on average 45 days, ranging from 41 to 57 days. On subjective evaluation the patients regarded both the course and the result of treatment as good. DISCUSSION In this paper the authors address the permanent conflict between concepts of surgical and conservative therapy. Their results fully support the fact that the freedom of motion of all joints for a greater part of treatment is necessary for healing as well as prevention of a subsequent restriction of the range of motion. They also provide evidence that this modified method facilitates healing without complications. The patients were satisfied with the outcome of treatment; there was no poor result reported. CONCLUSIONS The method of functional treatment for distal radius fractures is an effective procedure allowing for good bone healing with a minimum of complications. In addition, the treatment can almost exclusively be carried out in an out-patient department. The mechanism promoting the process of osteogenesis in its course is not known yet. However, it has to be mentioned that the method is time-consuming for both the physician and the patient. Key words: distal radius fracture, functional treatment, Sarmientos method.

[Cementless total hip replacement type S.F.: mid-term results]. / Strednedobé výsledky a nase zkusenosti s necementovanou endoprotézou kycelního kloubu typu S.F.

PURPOSE OF THE STUDY: The authors evaluate the mid-term results and their experience with the cementless total hip replacement Beznoska type S.F. "Slavík, Fencl" in a group of 40 patients. MATERIAL: During 2002, a total of 46 patients underwent implantation of a cementless total hip replacement (THR) type S.F. Six patients failed to come to the final follow-up at 5 years after surgery. Coxarthritis was the indication for primary surgery in the majority of the patients. The average age of the group, which comprised 20 men and 20 women, was 63 (50-75) years. METHODS: At the end of 2007, 40 patients were evaluated at an average follow-up of 62.5 months. The patients' age, gender, body mass index, physical activity, diagnosis on which indication for surgery was based, size of each cementless component and intra- and post-operative complications were recorded. The objective outcome was assessed using the Harris Hip Score (HHS), signs of secondary stability were evaluated on radiographs at 3, 6 and 12 months, then at 3 and 5 years after the primary THR. RESULTS: The primary fixation of all components was always good. In the post-operative period there was no THR dislocation and no loosening of the polyethylene acetabular liner from the titanium shell. One patient suffered a periprosthetic fracture following a fall. At 5-year follow-up, no evidence of acetabular loosening was found one patient required polyethylene liner exchange for excessive wear. Thirty-eight stems were evaluated as stable, with three stems showing ingrowth of a fibrous intermediate layer. Only one femoral component was assessed as unstable with a suspected late haematogenous infection. The mean HHS value was 45.6 before THR and 90.3 at 5 years after the primary surgery. The results were excellent in 24, very good in 12, fair in two and poor in two patients. DISCUSSION: If the correct surgical procedure is observed, a perfect press-fit fixation of both components can always be achieved. The S.F. type implant can also be used for a dysplastic acetabulum in this case a deeper reaming of the acetabular bed in preferred to acetabular augmentation (acetabuloplasty). The excessive polyethylene wear in one patient can be accounted for by the patient's overdone daily exercise the imperfect secondary osteointegration of three stems was probably due to the selection of a smaller femoral component than it was appropriate. When an undersized stem is used, insufficient implant osteointegration and a higher incidence of pain symptoms should be expected. The findings of signs of stress shielding were in accordance with those reported in the literature. CONCLUSIONS The mid-term clinical results and evidence of good osteointegration of both components five years after primary implantation of the THR type S.F. in 40 patients are very satisfactory. This group of patients will be followed up for another 5 years and evaluated.

[Conservative treatment using plasma rich in growth factors (PRGF) for injury to the ligamentous complex of the ankle]. / Konzervativní terapie poranení ligamentózního aparátu hlezna s vyuzitím PRGF.

PURPOSE OF THE STUDY: The authors describe the therapeutic utilization of separated/isolated autologous growth factors in semiconservative treatment of type III injury to the ankle ligamentous complex. MATERIAL: Between October 2004 and March 2005 a group of 11 patients, two women and nine men, aged 18 to 41 (average, 25.09) years with acute injury to the lateral ligamentous complex of the ankle were treated by plasma rich in growth factors (PRGF) infiltration. On functional radiographic examination, the post-traumatic lateral opening of the tibiotalar intraarticular space was 17.45 degrees (range, 12.0-30.0; s = 5.68). METHODS: The injured patients were clinically examined and standard forced inversion radiographs were made using topical anesthesia. Autologous PRGF activated with calcium chloride was used to infiltrate the injured tissues. The treatment was followed by immobilization of the joint and its subsequent rehabilitation. Clinical examination of injured tissues was carried out at 4 and 6 weeks of follow-up, using stability assessment tests and functional radiography of the ankle. Physical therapy included standard procedures, but faster regeneration of the soft tissues allowed for more exercises. RESULTS: The average time of healing was 5.18 weeks. Five patients showed no signs of instability at 4 weeks after therapy and could return to their previous sports activities. One patient had lateral ankle instability at 5 weeks and therefore the therapy continued with prolonged immobilization and then rehabilitation at a slower pace. The average lateral opening of the tibiotalar intra-articular space at 4 or 6 follow-up weeks was 4.73 degrees (range, 3.0 - 7.0; s = 1.19). At 6 weeks after therapy, 90.9% of the patients resumed their full sports activities. DISCUSSION: Ankle distortion with swelling, hematoma and pain, but with no radiographic findings of ligament lesions, is usually treated conservatively by ankle immobilization and early rehabilitation. When an injury to the fibular ankle ligaments occurs (i.e., opening of the tibiotalar intra-articular space laterally by more than 10 degrees), surgery and reconstruction of the injured tissues is indicated. An alternative treatment of acute injury to the ligamentous ankle complex includes application of growth factors into the injured tissues. The presence of growth factors facilitates the healing and remodeling of soft tissues and regenaration may begin before leukocytes infiltrate the affected site. At a relatively low level of interleukins, the inflammatory phase of healing is suppressed, pain is reduced and the process of reparation and regenaration is accelerated. CONCLUSIONS: The use of bioinductive properties of growth factors is one of the options for treating injuries to the ligamentous complex of the ankle. It can be used alternatively to conventional surgery or as an adjunct accelerating and improving the healing of traumatic lesions and postoperative conditions.

[The role of growth factors in the human organism and their use in medicine, especially in orthopedics and traumatology]. / Funkce rustových faktoru v lidském organismu a jejich vyuzití v medicíne, zejména v ortopedii a traumatologii.

The authors analyze one of the new therapeutic approaches - the use of autologous growth factors. Because the chemical structure of these proteins and their involvement in many functions of the organism affect the whole range of tissues, with a possibility to use them in human medicine. Growth factors, such as platelet-derived growth factor, transforming growth factor and others, exert effects on fibroplastic events during ontogenesis as well as on regeneration of tissues injured due to an accident or surgery. The preparation of therapeutic doses of growth factors consists of autologous blood collection, plasma separation and application of plasma rich in growth factors. The fibroplastic event involves chemotaxis and proliferation of cells, proteosynthesis, reparation and remodeling of tissues. The paper describes the method and is an introduction to studies on the utilization of growth factors in orthopaedics and traumatology.

Fluorescent advanced glycation end products in the detection of factual stages of cartilage degeneration.

Patients treated for knee disorders were included in this study. They were examined clinically (Lequesne and Tegner scores) and by standard X-ray investigation. Patients underwent a surgical procedure, either arthroscopy or knee replacement. At the initial phase of surgery, a sample of cartilage was taken for laboratory examination. Progression of the disorder and the clinical examination was correlated with the actual state of the cartilage using a novel fluorescence approach. The intrinsic fluorescence of cartilages was shown as a suitable and sensitive method for detection of the actual state of cartilages because the correlation with X-ray examination and clinical status was found. Intrinsic fluorescence properties of cartilages from patients with chondropathy and osteoarthritis were described and found to be age-dependent. We also observed a higher concentration of advanced glycation end products due to inflammatory and/or degenerative processes in the cartilage. In addition, acute pathological changes due to diseases such as meniscal lesions or anterior cruciate ligament rupture caused a significant increase of formation of advanced glycation end products even in the group of young patients. In fact, such an observation could be crucial and important for the detection of knee conditions suspected of early meniscal and/or ACL lesions especially among young patients.

Positive effect of oral supplementation with glycosaminoglycans and antioxidants on the regeneration of osteochondral defects in the knee joint.

The effect of oral supplementation with glycosaminoglycans (GAG) and radical scavengers (vitamin E/selenium) on the regeneration of osteochondral defects was investigated in rabbits. After introduction of defined osteochondral defects in the knee joint, groups of ten animals were given a GAG/vitamin E/selenium mixture or a placebo (milk sugar) for 6 weeks. Following sacrifice, histological and histochemical analysis was performed. The amount of synovial fluid was increased in the placebo group, while the viscosity of the synovial fluid was significantly enhanced in the GAG group. The amount of sulfated GAG in the osteochondral regenerates (8.8 +/- 3.6 % vs. 6.0 +/- 5.6 %; p <0.03) was significantly higher in the GAG group. In both groups, the GAG amount in the cartilage of the operated knee was significantly higher than in the non-involved knee (p <0.05). Histological analysis of the regenerates in the GAG group was superior in comparison with the placebo group. For the first time, a biological effect following oral supplementation with GAG was demonstrated in healing of osteochondral defects in vivo. These findings support the known positive clinical results.

Biomechanical characterization of cartilages by a novel approach of blunt impact testing.

The present article introduces a novel method of characterizing the macromechanical cartilage properties based on dynamic testing. The proposed approach of instrumented impact testing shows the possibility of more detailed investigation of the acting dynamic forces and corresponding deformations within the wide range of strain rates and loads, including the unloading part of stress-strain curves and hysteresis loops. The presented results of the unconfined compression testing of both the native joint cartilage tissues and potential substitute materials outlined the opportunity to measure the dissipation energy and thus to identify the initial mechanical deterioration symptoms and to introduce a better definition of material damage. Based on the analysis of measured specimen deformation, the intact and pathologically changed cartilage tissue can be distinguished and the differences revealed.

Composite hyaluronate-type I collagen-fibrin scaffold in the therapy of osteochondral defects in miniature pigs.

The potential of novel scaffold containing sodium hyaluronate, type I collagen, and fibrin was investigated in the regeneration of osteochondral defects in miniature pigs. Both autologous chondrocyte-seeded scaffolds and non-seeded scaffolds were implanted into two defects located in the non-weight-bearing zone of the femoral trochlea (defect A was located more distally and medially, defect B was located more proximally and laterally). Control defects were left untreated. Twelve weeks after the operation, the knees were evaluated in vivo using MRI. Six months after the implantation, the defects were analyzed using MRI, histological, and immunohistochemical analysis. In the A defects of chondrocyte-seeded scaffold group, hyaline cartilage and fibrocartilage was formed, containing type II collagen, acidic and neutral glycosaminoglycans while the non-seeded scaffold group was predominantly filled with fibrocartilage. Defects in the control group were predominantly filled with fibrous tissue. Histomorphometric analysis of photomicrographs revealed a significantly higher amount of hyaline cartilage in the cell-seeded scaffold group in A defects than in other groups. Both scaffold groups in A defects showed significantly less fibrous tissue than cell-seeded defects B and the control group. Both histological and MRI analysis proved that the novel composite scaffold has a potential to regenerate osteochondral defects within six months.

[Autologous chondrocyte implantation in the treatment of cartilage lesions of ankle joint]. / Transplantace kultivovaných autologních chondrocytu hlezenného kloubu.

PURPOSE OF THE STUDY: The authors present the results of surgical treatment of talar dome cartilage defects. They used the transplantation of autologous cultured chondrocytes in the form of a solid chondral graft. MATERIAL AND METHODS: Patients with chondral lesions categorized as grades II to IV by the Anderson classification or as grades II to IV by the Berndt and Harty classification were indicated for this treatment. After preoperative MRI examination, a small sample of healthy cartilage was harvested arthroscopically from the non-weight-bearing area of the talus and was sent to the Tissue Bank in Brno for chondrocyte cultivation. After 28 to 42 days the cultured chondrocytes were formed into a solid chondral graft, implanted at the damaged site of the talar dome and fixed with fibrin glue (Tissucol). RESULTS: Between July 2003 and October 2005 five patients, three males and two females, were treated using this method. Their age ranged from 22 to 46 years. Follow-up was 6 to 24 months, with an average of 12.6 months, and the patients were examined by MRI at 2 weeks, 2 and 6 months and at 1 year. The clinical results were evaluated on the basis of the Mazur and Weber scoring systems. CONCLUSIONS: A significant improvement in clinical function of the ankle joint was achieved in three patients and the condition remained unchanged in one patient. In one patient, the surgical outcome was too recent for evaluation, but the MRI results indicated tendency to good incorporation of the graft.

[Orthopaedic treatment of osteolytic lesions in long bones of multiple myeloma patients]. / Ortopedická lécba osteolytických lézí dlouhých kostí pri mnohocetném myelomu.

Treatment of the multiple myeloma has developed rapidly during the last years. Introduction of autologous transplantation in the ninetieth of the previous century radically prolonged the period of survival. New types of drugs influencing the metabolism of myeloma cells and their adhesion to neighbouring tissues brought promising improvement of the therapy results. In spite of the optimistic view, multiple myeloma represents an incurable disease and its multiplex manifestations in the skeleton endanger the patient by pathologic fractures and significant decrease of the duality of life. In the article we aimed to identify reliability of individual diagnostic methods. The manifold symptomatology of the disease implies the necessity of complex evaluation of the patient's status, considering the risks of surgical intervention and the possibility of related complications. In the surgical treatment selection of the most appropriate approach and type of implant related to the prognosis of survival with the aim to improve the quality of life of the patient.

[Therapy of severe chondral defects of the patella by autologous chondrocyte implantation]. / Lécba hlubokých chondrálních defektu pately transplantací kultivovaných autologních chondrocytu.

PURPOSE OF THE STUDY: The aim of this study was to present the results of treatment of deep chondral defects of the patella by transplantation of a solid chondral graft formed by autologous cultured chondrocytes. MATERIAL AND METHODS: Indications for autologous chondrocyte implantation most frequently included acute trauma to the knee, particularly the patella, which resulted in a severe focal cartilage defect. The lesions were assessed on the basis of the Bessette and Hunter classification preoperatively, and on the Outerbridge classification during arthroscopy. A sample of healthy cartilage was harvested from a non-weight-bearing area of the trochlea femoris. After cultivation of chondrocytes for 28 to 42 days in the tissue bank, a solid chondral graft, prepared with the use of fibrin glue (Tissucol), was ready for implantation. RESULTS: Six patients, two males and four females (average age, 21.1 years; range, 13 to 39 years) were treated by this method in the period from July 2003 to October 2005. Follow-up ranged from 1 to 25 months, with an average of 18.5 months. The patients were examined postoperatively by magnetic resonance imaging (MRI) at 2 weeks, 2 and 6 months, and at 1 year. The clinical results were evaluated by the Meyers, the Tegner and the Lysholm knee scoring systems. Two of the six patients, in whom the follow-up period was shorter than 6 months, were not included in the evaluation. CONCLUSIONS: A significant improvement in knee function was recorded when the preoperative and final follow-up stages were compared, as well as on comparison with the healthy contralateral knee joint. MRI examination showed good graft incorporation in all patients.

Polycaprolactone foam functionalized with chitosan microparticles - a suitable scaffold for cartilage regeneration.

For biodegradable porous scaffolds to have a potential application in cartilage regeneration, they should enable cell growth and differentiation and should have adequate mechanical properties. In this study, our aim was to prepare biocompatible scaffolds with improved biomechanical properties. To this end, we have developed foam scaffolds from poly-epsilon-caprolactone (PCL) with incorporated chitosan microparticles. The scaffolds were prepared by a salt leaching technique from either 10 or 15 wt% PCL solutions containing 0, 10 and 20 wt% chitosan microparticles, where the same amount and size of NaCl was used as a porogen in all the cases. PCL scaffolds without and with low amounts of chitosan (0 and 10 wt% chitosan) showed higher DNA content than scaffolds with high amounts of chitosan during a 22-day experiment. 10 wt% PCL with 10 and 20 wt% chitosan showed significantly increased viscoelastic properties compared to 15 wt% PCL scaffolds with 0 and 10 wt% chitosan. Thus, 10 wt% PCL scaffolds with 0 wt% and 10 wt% chitosan are potential scaffolds for cartilage regeneration.

[Experience with the use of hyaluronic Acid in the treatment of arthritis.]. / Zkusenosti s pouzitím hyaluronové kyseliny pri lécbe artrózy.

The authors describe their experience with hyaluronic acid (Hyalgan) in the treatment of arthritis in clinical and ambulatory practice. A total of 278 doses of Hyalgan were administered to 169 patients for treatment of arthritis of the knee, ankle, shoulder and hip joint. A certain limitation of treatment was the price of the preparation which had to be paid by the patients. The authors recorded an early subjective effect of the preparation, i.e. regression of pain, improved mobility and improvement of the clinical manifestations of osteoarthritis. It did not prove possible to detect an effect modifying the arthritic manifestations on the joint, although such an effect can be anticipated. Because no negative effect of the preparation on the joints or organism was found, Hyalgan can be considered an effective drug for osteoarthritis of the weight bearing joints. Key words: osteoarthritis, hyaluronic acid, intraarticular administration.