[Pigmented villonodular synovitis]. / Synovite villonodulaire.

OBJECTIVE: To evaluate clinical, radiological and histological characteristics as well as outcome of pigmented villonodular synovitis (PVNS) in 14 patients. METHODS: This retrospective study examined data from 14 cases of pathologically-confirmed PVNS over a 10-year period (1990-1999). RESULTS: All 14 cases (9 women and 5 men) of PVNS involved the knee. Mean age at diagnosis was 32.7 years. The principal functional signs were mechanical pain and disability. All patients had radiographs (normal for 8 patients); 3 had arthrography, which found diffuse cyst formations, 2 had MRI, which showed images characteristic of PVNS, and 4 had arthroscopy. All patients underwent complete surgical excision, and 4 also had osmic acid synoviorthesis. Recurrence occurred in 4 patients, within 10 months on average. CONCLUSION: MRI and arthroscopy improve the early management of pigmented villonodular synovitis.

Osmium tetroxide, used in the treatment of arthritic joints, is a fast mimic of superoxide dismutase.

Aqueous solutions of osmium tetroxide (OsO4) have been injected into arthritic knees for the past 45 years to chemically destroy diseased tissue, in a procedure termed "chemical synovectomy." Arthritis is an inflammatory disease. The primary inflammatory chemical species are the superoxide anion radical (O2.-) and nitric oxide (.NO), which combine to form the peroxynitrite anion (ONOO-). Here we show that OsO4 does not react with ONOO- but very efficiently catalyzes the dismutation of O2.- to O2 and H2O2. Using the pulse-radiolysis technique, the catalytic rate constant has been determined to be (1.43+/-0.04) x 10(9) M-1 s-1, independent of the pH in the 5.1-8.7 range. This value is about half that for the natural Cu,Zn-superoxide dismutase (Cu,Zn-SOD). Per unit mass, OsO4 is about 60 times more active than Cu,Zn-SOD. The catalytically active couple is OsVIII/OsVII, OsVIII oxidizing O2.- to O2 with a bimolecular rate constant of k=(2.6+/-0.1)x10(9) M-1 s-1 and OsVII reducing it to H2O2 with a bimolecular rate constant of (1.0+/-0.1)x10(9) M-1 s-1. Although lower valent osmium species are intrinsically poor catalysts, they are activated through oxidation by O2.- to the catalytic OsVIII/OsVII redox couple. The OsVIII/OsVII catalyst is stable to biochemicals other than proteins and peptides comprising histidine, cysteine, and dithiols.

Chemical synovectomy in haemophilia: status and challenges.

Chemical synovectomy has been used for the last three decades as an alternative for surgical synovectomy in the treatment of chronic haemophilic synovitis. Comparable results have been obtained with the many different radionuclides used: decreased bleeding, decreased pain and stable range of motion, in more than 50% of treated patients. Yttrium 90Y and Phosphorus 32P seem to be the isotopes of choice. Osmic acid and rifampicine have been used in a relatively small number of subjects. Global result of treatment with these two pro-ducts seems to be less favourable than with radionuclides. Late effects of chemical synovectomy are not known.

Chemical synoviorthesis with osmic acid in haemophilia.

Based on previous experience in inflammatory arthritis, a small number of open studies have evaluated the usefulness of chemical synoviorthesis with osmic acid in haemophilia, with various assessment criteria and a wide range of follow-up periods. Based on these studies, the efficacy of osmic acid seems modest, with 30-44% of good clinical and radiological results, but with fair or poor clinical results in other patients with a possible deleterious effect on cartilage. Osmic acid was found inferior to Yttrium-90 in one retrospective study. Synoviorthesis with osmic acid seems particularly indicated in haemophilic arthritis with no or mild radiological deterioration in children between 8 and 15 years of age. However, prospective randomized studies are clearly required to evaluate the symptomatic and structural effects of chemical and radioactive synoviorthesis in haemophilic arthritis.

A retrospective study on chemical and radioactive synovectomy in severe haemophilia patients with recurrent haemarthrosis.

Between 1970 and 1994, 116 chemical and 90 radioactive synovectomies were performed in 107 patients with severe haemophilia and two with type 3 von Willebrand's disease. The products used were osmic acid (OA) in 100 cases, 90-Yttrium in 35 cases, 186-Rhenium in 48, 169-Erbium in two, hexacetonide triamcinolone in 16 and radioactive gold in five cases. The use of radioactive colloids is not allowed in France in patients under 15 years of age. Twenty-nine patients had more than one synovectomy per joint. All patients were evaluated for 6 months post-synovectomy, using both a clinical and a radiological score. Six months after synovectomy, a good or excellent result was obtained for 81% of the joints treated with isotopes, compared with 44% of those treated with OA, P<0.001. This superiority of isotopes over osmic acid was still observed after 6 months for the 89 joints that were re-evaluated, with follow-up ranging from 1 to 9 years. It was possible to calculate a radiological score in 84 cases. With OA the best results were from the joints with the lowest scores pre-synovectomy (<7). No correlation could be established between the clinical and the radiological scores, due to the small size of the sample. In summary: (1) chemical and radioactive synovectomy are simple and safe procedures for haemophilic arthropathy, (2) in our series, after 6 months the efficacy of isotopic synovectomy was greater than that of chemical synovectomy, and this benefit seems to persist after 6 months, and up to 9 years in the group of patients with longer-term follow-up.

Monoarticular chronic synovitis in a child.

Lipoma arborescens is a villous lipomatous proliferation of the synovial membrane characterized by chronic and painless synovial effusion. The aetiology is unknown. It has to be included in the differential diagnosis of chronic monoarticular disease in childhood. Magnetic resonance imaging provides a highly efficient tool for the diagnosis of this very rare condition. This is indeed the fourth paediatric case reported. Rather than resorting to the often inconvenient surgical synovectomy commonly recommended, we chose to treat the knee of this 13-yr-old boy with intra-articular osmic acid.

Nonsurgical synovectomy in the treatment of arthropathy in Von Willebrand's Disease.

Von Willebrand's disease is the most common inherited bleeding disorder, with an overall prevalence in the general population of 0.8% to 1.3%. Hemarthrosis occurs mainly in the severest forms of the disease (type III), with a frequency of 3.5% to 11%, and can cause severe arthropathy similar to that seen in hemophilia. We retrospectively reviewed our experience with nonsurgical synovectomy in the treatment of recurrent hemarthrosis with arthropathy in patients with von Willebrand's disease. Four of our six patients had type III disease and the remaining two had type II disease. The age range was 13 to 63 years. The frequency of hemarthrosis prior to synovectomy was one to four per month. One (n = 2) or both (n = 1) knees were treated in 4 cases, one (n = 1) or both (n = 1) ankles in 3 cases and an elbow in one case. We used yttrium 90 in a dose of 5 mCi for one knee, rhenium 186 in a dose of 2 mCi for two ankles and the elbow and osmic acid for two knees and one ankle. Clinical and radiological results were evaluated six months after synovectomy using the World Federation of Hemophilia score. Radiologic lesions remained stable and clinical manifestations improved in every case (p < 0.05). Five patients achieved a complete remission. Safety was satisfactory. The clinical efficacy of synovectomy done, using radiocolloids or osmic acid in arthropathy due to von Willebrand's disease, seems similar to that in hemophilia.

Treatment of acute and chronic synovitis by non-surgical means.

This paper reviews personal experience in the treatment of recurrent haemarthrosis and chronic synovitis by non-surgical means. Experience with synoviorthesis with rifampicine and radioactive colloids is analyzed, and a multiple chromosomal study to demonstrate safety of radioactive injections is described. The results obtained are so very satisfactory as to recommend non-aggressive synoviorthesis as the treatment of choice to prevent recurrence of bleeding. Long experience in the treatment of chronic arthropathy with intrarticular corticosteroids and hyaluronic acid has shown very promising results.

[Chemical synovectomy in arthritis by intra-articular injection of osmic acid].

18 patients suffering from persistent synovitis despite medical therapy were treated with an intra-articular injection of osmic acid. After 1 year of follow-up, 68% had good results and there were no complications nor detectable radiographic evidence of disease progression. Because osmic acid is almost as effective as surgical synovectomy and is cheap and easy to administer, it can be recommended as the first choice for treatment of corticosteroid-resistant arthritis in the early stages of the disease.

Innovative treatment approaches for rheumatoid arthritis. Non-surgical synovectomy.

Rheumatoid patients with intractable knee effusions may benefit from medical or radio-isotopic synoviorthesis. These offer more convenient, less costly alternatives to surgery with similar long-term outcome. Temporary symptomatic relief may be obtained, but disease progression is unaffected. Potential adverse effects include development of osteoarthrosis with osmic acid and teratogenicity and mutagenicity with alkylating agents and radioisotopes.

Ultra estrutura da matriz extracelular da polpa de dentes humanos hígidos / Ultrastructural study of the extracellular matrix of pulps of healthy human teeth

Considerando o papel fisiológico e biológico da matriz extracelular, propomo-nos a estudar a estrutura da rede de glicosaminoglicanas (GAGs) e proteoglicanas (PGs) no tecido conjuntivo de polpas de dentes molares humanos hígidos de pacientes ao redor de 20 anos. As polpas foram fixadas para microscopia eletrônica de transmissäo em soluçöes de glutaraldeído com vermelho de rutênio e com tetróxido de ósmio reduzido. A rede de GAGs e PGs foi constituída por grânulos de filamentos dispostos numa extensa malha uniforme, contínua e compacta, com nítido inter-relacionamento com a estrutura e posicionamento das fibrilas colágenas e com a superfície de células do tecido conjuntivo

[Synoviorthesis--an alternative to synovectomy?]. / Synoviorthese--eine Alternative zur Synovektomie?

In the treatment of inflammatory rheumatic diseases with chronic course, operative and respectively arthroscopic synovectomy on the one hand and synoviorthesis on the other hand come into question. Synoviorthesis by corticosteroids has a very large indication if the corresponding measures of precaution are heeded. Chemical synoviorthesis, mainly by osmium tetroxide, is applied above all in exudative inflammatory diseases, whereas radiosynoviorthesis with the nuclides used at present is mainly applied in proliferative diseases; as a rule, synovectomy should be preferred in young patients. Likewise, synovectomy is the method of choice, respectively, in tenosynovitis and if reconstructive measures at the joint are necessary.

Intraarticular osmic acid in postinfectious arthritis persisting after treated bacterial arthritis.

We describe 4 patients successfully treated with intraarticular osmic acid for post-infectious arthritis persisting after apparent eradication of bacteria from the infected joint. In addition the bactericidal effect of osmic acid in vitro is demonstrated. We conclude that treatment with osmic acid carries no risk of iatrogenic infection; on the contrary, an antibacterial effect seems likely.

Sinoviórtese com ácido ósmico no tratamento das artropatias inflamatórias crônicas: estudo de 100 casos / Synoviorthese with osmic acid in the traitement of chronic inflammatory joint diseases: study of 100 cases

Os autores analisam o efeito do ácido ósmico como terapêutica auxiliar nas artropatias inflamatórias crônicas. O estudo inclui 65 casos de artrite reumatóide de adulto, 16 casos de artrite reumatóide juvenil, três de síndrome de Reiter, dois de espondilite anquilosante e seis de sinovite crônica recidivante de joelho. O período de observaçäo variou de seis a 66 meses. Noventa joelhos e 10 tornozelos foram infiltrados. Resultados excelentes e bons foram de 61,95 por cento; regulares: 9,78 por cento; maus: 28,26 por cento. Os excelentes e bons resultados predominaram nos estágios I e II da classificaçäo de Steinbrocker. Os efeitos colaterais foram: um caso de artrite septica; um caso de artrite microcristalina; e 10 casos de dor durante e após a injeçäo de ácido ósmico

Treatment of chronic knee synovitis with arthroscopic synovectomy after failure of intraarticular injection of radionuclide.

Although satisfactory results have been obtained with conventional synovectomy of the knee, there are frequent complications, and a long period of rehabilitation is necessary after this surgery. We performed arthroscopic synovectomy of the knees of 30 patients (33 knees), 22 of whom had rheumatoid arthritis. These patients underwent the procedure after failure to respond to an intraarticular injection of either osmic acid or yttrium 90. The operated knee was moved 3-5 hours after the arthroscopy, and the patients walked the next day. No rehabilitation was needed. The followup period ranged from 6 months to 36 months, with an average of 17.7 months. Except for 1 patient with severe arthritis, all patients experienced improvement. Results were rated as "good" or "very good" in 27 knees. Six months after synovectomy, the patients were asked to rate their improvement; the mean +/- SEM degree of improvement was 79.1 +/- 22.9%. All patients had significant improvement in the range of motion of the knee. One patient required manipulation of the knee (while under anesthesia) soon after the arthroscopy. There were no other complications. There was no detectable radiographic evidence of disease progression in 24 patients who were seen 1 year after the procedure or in 9 patients who were seen 2 years after the arthroscopy. Thus, arthroscopic synovectomy appears to be an effective and simple treatment for chronic knee synovitis, and has a low morbidity rate.