[Radial Head Replacement: Management of Elbow and Forearm Instability after Comminuted Radial Head Fractures Associated with Elbow Dislocation]. / Endoprotéza hlavice radia: resení nestability lokte a predloktí pri trístivých zlomeninách hlavice radia spojených s luxací lokte.

PURPOSE OF THE STUDY: This manuscript aims to identify an indication algorithm for the surgical treatment of radial head fractures associated with elbow dislocation. The study compares the mid-term functional outcomes of patients with multifragment radial head fracture treated by resection with the outcomes of patients treated with radial head replacement. MATERIAL AND METHODS: The cohort of 34 patients who sustained a radial head fracture at the mean age of 42.5 years (age range 20-81 years) was broken down into two groups by type of surgery. The EXT group consists of 20 patients with the radial head fracture treated by radial head resection. The END group includes 14 patients treated with the radial head replacement. In all patients, the radial head fracture was associated with elbow dislocation (type IV fracture according to the Mason-Johnston classification). The modified Kocher's surgical approach was used in all patients of both the groups. In the EXT group, resection of the fragmented radial head was performed. In the END group, the ExploR® Modular Radial Head System (Zimmer, Biomet, USA) was used, consisting of a CoCr (cobalt chromium) alloy head and a titanium stem. The pain and the range of motion of the elbow and forearm were evaluated after the completion of the outpatient rehabilitation (the mean follow-up period was 2.4 years). Simultaneously, the elbow joint stability was assessed. Radiographs were taken to detect heterotopic ossifications, proximalization of the radius, and any signs of prosthesis loosening. The frequency of reoperations was followed-up. The MEPS (Mayo Elbow Performance Score) was calculated. RESULTS: In the EXT group, the mean elbow flexion was 117.5° and the mean pronation/supination was 166.9°. In 50% of patients, the MEPS obtained was greater than 90 points, which means an excellent functional outcome. In 1 patient (5%), recurrent elbow dislocation occurred which was the reason for revision surgery (elbow transfixation with the Kirschner wires and medial collateral ligament suture). Revision surgery was also performed in 2 patients (10%) in whom not all the radial head fragments were removed. Moreover, also observed was elbow joint instability (2 patients) and temporary radial nerve paralysis (1 patient). In 1 case discrete proximalization of the radius developed. The patients in the END group showed the mean elbow flexion of 112° and the mean pronation/supination of 135°. The MEPS obtained from 69% of patients was greater than 90 points, which means an excellent outcome. The pain under load was reported by 3 patients (21%). In 5 patients (35%), the X-rays showed radiolucent zone around the stem of the prosthesis. Neither revision surgery, nor prosthesis removal has been performed yet in any patient. No instability, neurological complications or infections have been reported. In both EXT and END group heterotopic ossifications have developed in 4 patients. CONCLUSIONS: Radial head replacement compared to the radial head resection in the management of multifragment fractures associated with elbow dislocations increase the elbow and forearm stability. The group of patients with an implanted radial head prosthesis shows a higher percentage of patients achieving excellent functional outcome than the group of patients with radial head resection. KEY WORDS: radial head, elbow, fracture, dislocation, resection, prosthesis.

[Four-Corner Arthrodesis of the Wrist with Dorsal Circular Plate - a Retrospective Monocentric Study]. / Ctyrrohá déza karpu pomocí dorzální cirkulární dlahy ­ retrospektivní monocentrická studie.

PURPOSE OF THE STUDY Our study aimed to evaluate a group of patients who in the period from 2005 to 2014 underwent a four-corner arthrodesis of the wrist in our department. We also wanted to verify the hypothesis as to whether the use of conventional dorsal plate without the application of bone grafts leads to comparable results as the use of dorsal locking plates and routine application of bone grafts. MATERIAL AND METHODS Throughout the years 2005 to 2014 the four-corner arthrodesis of the wrist was performed in our department in a total of 62 patients, in two cases bilaterally. The indication was the diagnosis of SLAC/SNAC grade III. Normed RondoFix implant was used in all the cases. Following the surgery, the wrist was immobilized by a volar plaster splint for the period of 2 weeks and subsequently orthosis was applied for additional 4 weeks. The wrist mobilisation started in week seven when the orthosis was removed, the patients were allowed full load on the wrist 3 months after the surgery. Our group of patients was evaluated retrospectively, a total of 53 operated wrists in 51 patients were assessed. The assessment was carried out based on a radiograph of the wrist, range of motion, Mayo Modified Wrist Score, DASH Score and grip strength test. RESULTS The mean range of motion in sagittal plane was 63.7°, in frontal plane the mean value was 32.1°. According to the Mayo Modified Wrist Score 37 patients were rated "excellent" or "good". Due to the presence of moderate pain, the result in other 10 patients was assessed as "satisfactory". In a total of 4 patients the result was assessed as "weak", in two of them for a presence of non-union and in other two for severe pain under load. One of these patients underwent bilateral surgery and reported severe pain in both the wrists. Regarding DASH score, the best result equalled 0, the worst 65.83, with the mean of 20.5. The grip strength ranged from 8 to 54 kg, with the mean value of 27.5 kg. In two patients, a non-union occurred. In the first case the extraction of implant and re-arthrodesis was performed due to severe pain and screw migration. The patient is now 22 months after the surgery and the radiographs show that the arthrodesis has healed and the patient has no clinical difficulties. The second patient did not report any difficulties, therefore he is only subject to follow-up. No cases of screw or plate breakage were reported. In one case, the patient reported pain in the region of radial styloid process. A revision was indicated with radial styloidectomy and decompression of tendons of m. extensor pollicis brevis and m. abductor pollicis longus. As a result the patient had no clinical difficulty. One case of wrist radial deviation was recorded. It was managed by corrective wedge osteotomy and reosteosynthesis using a circular dorsal plate. In one patient dorsal impingement occurred, accompanied by limited range of motion and pain. Extraction of OS material was indicated and the patient was relieved of any difficulties. We have recorded aseptic necrosis of lunate bone in one case. DISCUSSION When comparing the functional results such as the range of motion and grip strength, our results are fully comparable to previously published papers. In papers where DASH was referred to, its value ranges from 13 to 29.82, which is fully consistent with our observations with the final value of 20.5. The incidence of non-union and the degree of complications is not deviating from the values included in other publications either. In all the mentioned publications the authors refer to routine use of bone grafts. The publications evaluating the use of locking plates do not report different results either. CONCLUSIONS In case of correct indication, the four-corner arthrodesis of the wrist represents a very good solution. In our group of patients, we confirmed the hypothesis that equally good results as with the use of locking plates can be achieved when using a non-locking plate system. Essential is the proper correction of DISI and primary good congruence between fused carpal bones instead of the use of bone grafts. Key words: SLAC wrist, SNAC wrist, four-corner arthrodesis, partial wrist fusion.

[Spontaneous Tendon Ruptures in the Rheumatoid Hand]. / Spontánní slachové ruptury v oblasti revmatické ruky.

A spontaneous tendon rupture is a direct consequence of rheumatoid inflammation and can appear without any noticeable impact, often during sleep. The patient then presents with inability to flex or extend metacarpophalageal or interphalangeal joints. Multiple ruptures resulting in impaired function of several fingers can also occur and markedly limit the hand's grip strength. A tear may arise from either mechanical injury to the tendon along its course over bone or connective tissues, or by biochemical action of lysosomal enzymes, released during the inflammation process, on the connective tissue of the tendon. Ischaemic damage to a part of the tendon due to constriction of vessels supplying the peritenonium is found in hypertrophic peri-tenosynovitis. Spontaneous ruptures can be prevented, in the first place, by early synovectomy and then by a number of prophylactic procedures on soft tissues and carpal bones, which can stop or at least slow down the development of severe axial deformities of the wrist and hand. Simple end-to-end suture of the stumps is usually not possible; tendon repair surgery using free grafts or, more often, intact tendon transfer is necessary. In the flexor part, transfer of the superficial flexor tendon to a stump of the deep flexor tendon is frequently performed; a free graft can also be used at a two-stage tendon reconstruction. The repair of flexor tendons is technically more demanding and the results are less satisfactory compared to repair surgery on the extensor tendon. Key words: rheumatoid arthritis, metacarpophalageal joint, interphalangeal joint, tendon rupture.

[Shape-memory osteosynthesis for trapeziometacarpal joint arthrodesis]. / Technika artrodézy trapezometakarpálního kloubu pametovou osteosyntézou.

PURPOSE OF THE STUDY: Arthrodesis of the trapeziometacarpal joint is the method of choice in the treatment of degenerative arthritis of this joint. This procedure was indicated most frequently in middle-age patients doing hard manual labor. Methods for achieving a solid fusion of the trapeziometacarpal joint are known and often reported in the literature. Frequently, they are associated with some failure rate, particularly as concerns bone union. Our study presents a simple and effective method verified in cadaver specimens and then currently used at our department. MATERIAL AND METHODS: The procedure for arthrodesis of the trapeziometacarpal joint was verified fist in fixed wrist and hand specimens at the Institute of Anatomy, 1 st Faculty of Medicine, Charles University in Prague. If the original shape of the basal thumb joint between the trapezium and the metacarpal is maintained, it allows for correct reduction and subsequent arthrodesis in a required position. In patients, surgical treatment included the use of implants, two DePuy shape-memory staples, which facilitate sufficient fragment compression and provide stable fixation. The staples were inserted in pre-drilled and gauged tunnels in the body of the trapezium and in the proximal metaphysis of the fist metacarpal. RESULTS: Between 2011 and 2014, the procedure was used in 14 patients diagnosed with primary arthritis of the trapeziometacarpal joint. The group comprised nine women and five men, the average age was 52 years and the range was 44 to 69 years. Surgery was most frequently carried out on the dominant upper extremity (85%); there was no bilateral surgery. The average follow-up was 18.3 months (range, 5 to 39 months). Solid fusion was recorded at 7 weeks after surgery in all patients except for the one still treated at the time of this paper submission. All patients were free of pain, ten reported satisfaction with grip strength and hand function, the rest would have preferred improvement in fine motor skills of the thumb. All of them found the cosmetic appearance of the hand satisfactory.. DISCUSSION: The methods generally used for trapeziometacarpal joint arthrodesis are reported to carry some risk of pseudarthrosis development. A lot of modifications have been described, from conventional procedures using AO lag screws or Kirschner wires to up-to-date plate systems involving angle-stable fixation. Total fusion of the trapeziometacarpal joint is disputable in patients with rheumatoid arthritis from the technical point of view as well as the relevance of indication criteria. Some authors consider this procedure a contraindication for patients with rheumatoid arthritis. The use of joint replacement in treating trapeziometacarpal joint arthritis is another complex issue. CONCLUSIONS: An arthrodesis of the trapeziometacarpal joint based on careful assessment of indication criteria proved to be a simple, effective and low-cost method of stable osteosynthesis that provided good conditions for solid fusion of the trapezium with the base of the fist metacarpal. It allowed for sufficient abduction and opposition of the thumb, thus permitting satisfactory hand grip strength and full involvement in everyday life activities and occupations. It provided stability of the thumb, its painless movement and good cosmetic looks.

[Comparison of in vivo characteristics of polyethylene wear particles produced by a metal and a ceramic femoral component in total knee replacement]. / Srovnání oterových charakteristik polyetylenu in vivo u náhrad kolena s kovovou a keramickou femorální komponentou.

PURPOSE OF THE STUDY: The aim of the study was to evaluate in vivo and compare, in terms of the quality and number of ultra high-molecular polyethylene (UHMWPE) wear particles, total knee replacements of identical construction differing only in the material used for femoral component production, i.e., CoCrMo alloy or ZrO2 ceramics. MATERIAL AND METHODS: Samples of peri-prosthetic granuloma tissue were collected in two patients with total knee replacement suffering from implant migration, who were matched in relevant characteristics. The primary knee replacement in Patient 1 with a CoCrMo femoral component was done 7.2 years and in Patient 2 with a ZrO2 implant 6.8 years before this assessment. The polyethylene wear-induced granuloma was analysed by the MORF method enabling us to assess the shape and size of wear debris and the IRc method for assessment of particle concentration. RESULTS: In the granuloma tissue samples of Patient 1, on the average, particles were 0.30 mm in size and their relative volume was 0.19. In the Patient 2 tissue samples, the average size of particles was 0.33 mm and their relative volume was 0.26. There was no significant difference in either particle morphology or their concentration in the granuloma tissue between the two patients. DISCUSSION: One of the options of how to reduce the production of polyethylene wear particles is to improve the tribological properties of contacting surfaces in total knee replacement by substituting a cobalt-chrome femoral component with a zirconia ceramic femoral component. The previous in vitro testing carried out with a mechanical simulator under conditions approaching real weight-bearing in the human body did show a nearly three-fold decrease in the number of UHMWPE wear particles in zirconia components. The evaluation of granuloma tissue induced by the activity of a real prosthetic joint for nearly seven years, however, did not reveal any great difference in either quality or quantity of polyethylene debris between the two replacements. The difference of surface roughness between CoCrMo (Ra = 0.05) and ZrO2 (Ra = 0.02) components did not play any role in in vivo conditions. CONCLUSIONS In accordance with a previous clinical study, this evaluation of the quality and quantity of UHMWPE wear particles produced by a ceramic femoral component in vivo failed to demonstrate any advantage of zirconia ceramic components over the cobalt-chrome femoral components so far used.

Surface modification of cyclic olefin copolymers for osteochondral defect repair can increase pro-destructive potential of human chondrocytes in vitro.

Materials on the basis of cycloolefin copolymers (COC) are suitable for subchondral defect repairs. The objective of this study was to evaluate the influence of surface modification of COC and COC/LLDPE blends on the viability and gene expression of chondrocytes. Human chondrocytes were incubated on the surface of the studied materials. Half of the materials were plasmatically modified with a subsequent type II collagen application. The gene expression of matrix metalloproteinases (MMP-1,-3,-13), pro-inflammatory cytokines (IL-1, TNF-alpha) and apoptotic molecules (BAX, Bcl-2) was evaluated using quantitative Taq-Man PCR after 48 h incubation. Chondrocyte viability was evaluated by the MTT test after 2, 4 and 8 days of incubation. The synthesis of MMPs was measured by ELISA assay in cell culture medium after 48 h of incubation. Chondrocytes incubated on plasmatically modified in contrast to unmodified materials demonstrated significantly increased gene expression of IL-1 (p<0.05), MMP-1 and MMP-3 (p<0.05 for both comparisons) as well as MMP-13 (p<0.001). Increased gene expression was confirmed by significantly increased production of active forms of particular MMPs into the cell culture medium. Unlike surface unmodified polymers, the modified materials showed time-dependent reduction of chondrocyte viability. The gene expression of TNF-alpha and apoptotic molecules by chondrocytes was not significantly changed by different materials. Cycloolefin copolymers and their blends may represent suitable materials for tissue engineering, however, their surface modification followed by collagen type II application may, at least under in vitro conditions, reduce the viability of chondrocytes and induce their pro-destructive behavior. The potential benefit or disadvantage of surface modifications of materials for osteochondral defect repairs needs to be further elucidated.

[Os Pisiforme transposition in the treatment of Kienböck's disease - long term results]. / Transpozice os pisiforme pri resení rozvinutých stadií morbus Kienböck - dlouhodobé výsledky.

PURPOSE OF THE STUDY: One of the methods used for treatment of Kienböck's disease is based on transposition of the pisiform bone into free space created by removal of the lunate bone. It is performed in patients with stage IIIB to IV, as assessed by Lichtmann's score. However, this operative procedure has so far lacked an unequivocal assessment of its therapeutic value. The aim of our work was to assess the therapeutic effect of the Kuhlmann method in the treatment of advanced stages of Kienböck's disease. MATERIAL: From January 1996, eighteen patients (18 wrists) diagnosed with Kienböck's disease were operated on, using the Kuhlmann method, and the group of these patients was included in this follow-up study. The average follow-up time was 7.6 +/- 2.3 years. METHODS: The results were evaluated on the basis of subjective (VAS) and functional criteria (ROM, grip force, DASH questionnaire and combined Cooney score questionnaires) and radiological assessment (arthritis evaluation, C.H.I., Natrass index, RSA). RESULTS: All patients experienced pain relief. The average pain assessment by VAS (10-point scale) before and after the procedure was 8.76 +/- 0.9 and 2.94 +/- 1.59, respectively. The range of motion was reduced on the operated extremity (70% compared to non-operated) as well as the grip test (57%). The average DASH score at the time of study was 20.9 +/- 12.2 and the average Cooney score was 67.6 +/- 17.4. Before the operation, eleven wrists showed signs of osteoarthritis. At the follow-up evaluation, arthritis was present in fifteen patients.We found a significant difference in average radiological parameters characterizing a carpal collapse deformity (C.H.I., Natrass index, RSA) - all parameters showed deteriorating tendencies. DISCUSSION: In nine patients, necrotic changes of the lunate occurred. In the patients whose pisiforme was not affected, a moderate retardation of carpal collapse occurred. However, the discrepancy between relevant indicators (C.H.I, Natrass index, RSA) was not statistically significant when comparing both groups. Therefore, we cannot conclude as to whether or not a vital transposed pisiforme bone impedes the development of carpal collapse. The only proved difference between these two groups was in pain evaluation, measured by VAS, after the procedure CONCLUSION: Although there was a good subjective assessment of the operation results, we are of the opinion that this method should not be used as a routine surgical procedure for advanced Kienböck disease. In view of a large number of failed cases we believe that this method should be considered very carefully.

[First experience with total wrist replacement using an implant of our design]. / První zkusenosti s totální náhradou zápestí nasí konstrukce.

PURPOSE OF THE STUDY: To present the results of total wrist replacement with a cementless prosthesis designed by us. MATERIAL AND METHODS: A group of five men and 27 women treated between 2004 and 2007 was evaluated. The average age was 51.6 years and follow-up ranged from 4 to 38 months, with an average of 9.4 months. Indications for surgery included wrist destruction due to rheumatoid arthritis, arthritis or psoriatic arthropathy. Subjective evaluation recorded satisfaction of the patients with the wrist range of motion, cosmetic appearance of the hand and pain relief. The range of motion was assessed with a goniometer at 4 months of follow-up on average. Radiographs were made immediately after surgery and then at 6 and 12 months post-operatively. RESULTS: All patients reported pain relief, 23 were satisfied with wrist mobility and hand appearance, and seven were only partly satisfied and would have preferred a greater range of motion. Two patients were dissatisfied with an ulnar deviation of the carpal axis and therefore revision arthroplasty of the radial ligamentary and tendinous structures was planned. No aseptic or septic loosening of the implant or its migration was found. DISCUSSION: The current total wrist arthroplasty has evolved from Swanson silastic implants to prostheses with a metal-on-polyethylene bearing whose active surfaces are firmly fixed in bone. In today's Europe, the most frequently used prostheses are Meuli implants or the latest modification of the Guepar implant, which is very close to the Universal 2 implant. In the USA since 1985, Professor's Beckenbaugh's BIAX implant has continuously been improved. The implant designed by us is based on all well-tired implant components and aims at being as similar to the anatomical wrist structures as possible. The socket is fixed in the distal radius. The carpal components involve the main fixation shaft for the third metacarpal and a short antirotation pin for the second metacarpal base. A metal head is assembled onto a tapered shaft extending from the carpal component transversal zone. The implant is made of titanium alloy, in some parts coated with hydroxyapatite; the sockets has a polyethylene liner. CONCLUSION: Total wrist replacement is usually preceded, particularly in surgery for rheumatoid arthritis, by operations intended to prevent or slow down gradual wrist destruction. The usual salvage procedures include surgery on soft tissues (synovectomy, tenodesis, tendon reconstruction) and/or bone (limited wrist arthrodesis, Sauve-Kapandji procedure). These procedures usually have a temporary effect and total replacement will be the next step in surgical treatment. For the most severe destruction associated with subluxation and wrist instability, total arthrodesis in a neutral wrist position still remains the method of choice. The first results with use of the implant of our design show that this total wrist replacement allows us to preserve or restore the wrist range of motion and to improved grip strength.

Periprosthetic osteolysis and its association with RANKL expression.

Extensive osteolysis adjacent to orthopedic implants is often associated with wear particles of prosthetic material. The activation of the RANKL/RANK/OPG system is considered to be a likely cause of periprosthetic osteolysis leading to implant failure. The aim of this study was to examine the possible correlation between the clinical extent of osteolysis, the number of wear particles and expression of the osteoclastic mediator RANKL (receptor activator of nuclear factor kappa B ligand) in the tissues around aseptically loosened cemented and non-cemented total hip replacements. Periprosthetic tissues were harvested from 59 patients undergoing revision of hip replacement for aseptic loosening. We observed RANKL-positive cells in 23 of our 59 patients, their presence was noted predominantly in tissues with a loosened cemented endoprosthesis. We have found that RANKL is present only in tissues with a large amount of wear debris and predominantly in cases involving loosened cemented implants.

Resistin in rheumatoid arthritis synovial tissue, synovial fluid and serum.

BACKGROUND: Resistin is a newly identified adipocytokine which has demonstrated links between obesity and insulin resistance in rodents. In humans, proinflammatory properties of resistin are superior to its insulin resistance-inducing effects. OBJECTIVES: To assess resistin expression in synovial tissues, serum and synovial fluid from patients with rheumatoid arthritis, osteoarthritis and spondylarthropathies (SpA), and to study its relationship with inflammatory status and rheumatoid arthritis disease activity. METHODS: Resistin expression and localisation in synovial tissue was determined by immunohistochemistry and confocal microscopy. Serum and synovial fluid resistin, leptin, interleukin (IL)1beta, IL6, IL8, tumour necrosis factor alpha, and monocyte chemoattractant protein-1 levels were measured. The clinical activity of patients with rheumatoid arthritis was assessed according to the 28 joint count Disease Activity Score (DAS28). RESULTS: Resistin was detected in the synovium in both rheumatoid arthritis and osteoarthritis. Staining in the sublining layer was more intensive in patients with rheumatoid arthritis compared with those with osteoarthritis. In rheumatoid arthritis, macrophages (CD68), B lymphocytes (CD20) and plasma cells (CD138) but not T lymphocytes (CD3) showed colocalisation with resistin. Synovial fluid resistin was higher in patients with rheumatoid arthritis than in those with SpA or osteoarthritis (both p<0.001). In patients with rheumatoid arthritis and SpA, serum resistin levels were higher than those with osteoarthritis (p<0.01). Increased serum resistin in patients with rheumatoid arthritis correlated with both CRP (r=0.53, p<0.02), and DAS28 (r=0.44, p<0.05), but not with selected (adipo) cytokines. CONCLUSION: The upregulated resistin at local sites of inflammation and the link between serum resistin, inflammation and disease activity suggest a role for resistin in the pathogenesis of rheumatoid arthritis.

[Ten years' experience with our method of wrist joint arthrodesis]. / Desetileté zkusenosti s vlastní metodou totální artrodézy zápestního kloubu.

PURPOSE OF THE STUDY: Total arthrodesis of the carpal joint is a complex operative procedure that results in the restoration of joint stability in frontal and sagittal planes and improvement in function of the tendons of digits' extensors and flexors. We developed our own method based on the use of a special implant; in this study we report our long-term results. MATERIAL: Since 1992 we have carried out 54 total carpal arthrodeses, using our method, on 51 patients; three patients were treated bilaterally. Both wrists were treated in. This group comprised 34 women and 19 men, with the average age of 47.6 years. We used the modified method mainly in patients with stage IV rheumatic carpal destruction (Larsen classification) or in those with wrist destruction due to arthritis or psoriasis. In two patients, this method was indicated because of a non-reparable lesion of the nervus radialis. It was also used in two patients who had their wrist replacements removed due to failure. METHODS: The procedure was carried out, with a tourniquet applied to the upper arm, from the dorsal approach to the carpal joint. After opening the capsule, using an oscillating saw, we resected the facies articularis radii, the carpal bones, which were freed from cartilage and turned into a cancellous in situ filling, and the distal ulna. This procedure prepared the operation field for the application of our plate. This L-shaped plate, only 2 mm thick, with its concave curve fitting the palm, allows for three-point fixation of the metacarpal region and also maintains slight compression. RESULTS: In all the patients, we achieved osseous fusion detectable by radiography and clinical examination on average at 12 weeks postoperatively. The grasping function of the hand improved in all patients because the carpal axis was adjusted to a functionally convenient position. The resection of the distal ulna, which is a part of our method, removed pain caused by supination or pronation. The patients reported the absence of pain, instability and edema of the wrist. DISCUSSION: The aim of any method for total wrist arthrodesis is the firm fixation of resection-treated articular surfaces of the radius, carpal bones and metacarpal bases for a period long enough to allow for their complete fusion. These techniques involve intraosseous procedures, the use of plates, osteorrhaphy and external fixation. Most of these methods use massive corticocancellous grafts collected from the hipbone crest. The critical point of all methods is fixation of the metacarpal region. CONCLUSIONS: The method described here is based on an original implant in the form of an L-shaped plate that permits sufficient fixation without using grafts taken from the pelvis. In patients with rheumatic arthritis, if needed, it facilitates peritenosynovectomy or reconstruction of spontaneous tendon ruptures in one operation. It does not require long-term immobilization in plaster cast and permits early rehabilitation of finger joints.

[Polyethylene disease]. / Polyetylenová choroba.

PURPOSE OF THE STUDY: The experience obtained during revision surgery and findings of polyethylene granulomas in surrounding tissues of replacement as well as marked differences in the viability of implants resulted in the study of polyethylene disease and its basic mechanisms producing the development of osteoaggressive granulomas. We investigated the morphology of particles and their number in tissues surrounding the implant. The aim of our study was to develop a method for the detection of polyethylene particles in tissues, to identify different types of wear and to assess factors that may influence the viability of joint arthroplasty in general. MATERIAL: Every revizion of joint arthroplasty performed during the last five years was evaluated in terms of the presence of polyethylene granules and the viability state of articular polyethylene inserts. A total of 55 samples were taken from tissues around loosened endoprostheses. The location of each sample was exactly determined. METHOD: A technique was developed to identify wear particles and to visualize them after all organic structures of a polyethylene granuloma were dissolved with nitrogenic acid. RESULTS: The viability of articular polyethylene implants showed extreme differences in relation to different periods of manufacture and probably also to different methods of sterilization. Articular inserts sterilized with formaldehyde (the method used at the beginning of arthroplasty in our country) showed the highest viability and the lowest wear. The polyethylene particles present in tissues surrounding the implant were characterized in terms of morphology and size. DISCUSSION: The comparison of literature data and our results has revealed that there are many unknown facts about the quality and structure of polyethylene. The method of sterilization also appears to play a role. Because the issue is complex, we were not able to identify all factors leading, in some cases, to an early and unexpected failure of the implant and we consider further investigation to be necessary. CONCLUSIONS: Polyethylene disease is an important factor limiting the viability of joint arthroplasty. It results from a complex interaction of polyethylene particles arising by wear with surrounding tissues. The particles, less than 0.5 micron in size, are phagocytized by macrophages and, by complex mechanism of expression of inflammation mediators, they result in the inhibition of osteogenesis and activation of osteoclastic processes. The previous methods of sterilization with formaldehyde vapors apparently reduced wear influenced the resistance of polyethylene to wear to a lesser degree. A method was developed to detect these particles and to characterize their morphology in the tissues of a polyethylene granuloma.

[Deformities of the forefoot in patients with rheumatoid arthritis--results of surgical treatment]. / Deformity prednozí u pacientu s revmatoidní artritidou--výsledky operacní lécby.

PURPOSE OF THE STUDY: Rheumatoid arthritis affects the foot very frequently. The transversal arch of the foot gradually declines due to the inflammation, the metatarsal heads protrude in the sole of the foot which is accompanied by painful bunions and sometimes also skin necrosis. The great toe turns into a valgus position and pronation. Walking is very painful. MATERIAL: The authors evaluate a group of patients operated on for the deformities of the forefoot between 1995 and 2002. METHODS: In the deformities of the forefoot the authors use resection of the heads of II-V metatarsals. They use a plantar surgical approach during which they remove bunions under the heads of the metatarsals. Then they gradually perform resection of the heads of--V metatarsals. In case of the great toe they prefer resection after Keller. In 5 cases they used fusion of the MTP joint of the great toe. They use fusion only in cases of a marked valgus position of the great toe. Where I MTT was in a significantly varus position, they applied in 3 cases the Lapidus procedure. RESULTS: Between 1995 and 2002 they operated on 92 patients, in 38 of them the surgery was performed bilaterally. Evaluation covered 130 surgeries. In 85 cases the patients had rheumatoid arthritis, in 7 the basic diagnosis was psoriatic arthritis. The group included 72 women and 20 men. The average age at the time of surgery was 38.4 years. Eighty-two (63.1%) patients were without pain 7 (5.4%) patients had severe pain. The authors monitored the occurrence of revalgization of the great toe after Keller resection arthroplasty--of 77 patients revalgization occurred in 23 cases (29.8%). The complications included 3 times a late infect 1-2 years after the surgery after the protrated infect of the organs, 3 times a skin necrosis between the great toe and 2nd metatarsal, when prior to the surgery there was a significant valgus deformity and after the correction of the great toe there was a skin tension in this region, 6 times a delayed healing of the wound on the sole of the foot. DISCUSSION: The authors present different surgical techniques of the forefoot and the great toe of the foot used by different authors. CONCLUSION: As the patients suffer from a polyarticular affection the emphasis is put on the individual approach and a properly timed operation. In this respect of vital importance is the cooperation involving a rheumatologist, orthopaedic surgeon, physical therapist and prosthetic department. Orthopaedic insoles and orthopaedic shoes are an integral part of the comprehensive therapy. Surgical treatment is not very demanding for patients and in most cases it brings a significant relief.

[Postoperative sciatic nerve palsy after hip joint surgery.]. / Poskození sedacího nervu pri operacích kycelního kloubu.

Postoperative impairment of the function after surgery in the region of hip joint has always a strong negative impact on the final outcome of the surgery. In most patient neurological functions are fully restored, residual impairment affects only a smaller part of them. Specialist literature most frequently deals with the development of lesion during THR. The risk of injury of the nerve is significantly higher in revision surgery relating toTHR reimplantation or inTHR in a changed anatomical region. The cause which leads to the impairment of the sciatic nerve is considered direct injury of the nerve during the surgery, ischemization of the nerve tissue, compression or excessive distraction of the nerve, compression of the nerve by bone cement having penetrated to a place of its course, thermic injury of the nerve during polymerization of bone cement, injury during dislocation or revision of THE, compression of the nerve by hematoma in the surgical wound, compression of the nerve by a bone prominence or implanted acetabular component. Another aetiolgical factor which may be the cause of the impairment of the function of the sciatic nerve or any of its branches is in the authors' view overdistension of the sciatic nerve in the region of contracted pelvitrochanteric muscles after their excision from origin which is necessary for obtaining a sufficient access to the proximal femur during the implantation of the stem. Such overdistension may occur mainly in case of the present of any variant anatomical relations of m. piriformis and the sciatic nerve of one of its portions. Literature states the incidence of different realtions of both structures between 15_34 %. Authors studied this incidence on 51 cadaveric specimens and found the above mentioned "risk" situation in 10 cases (20 %). Key words: sciatic nerve, hip joint, total hip replacement, sciatic nerve palsy.