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K Rohe

Publications and source records attributed to K Rohe.

16 recordsLinked to original sources
PubMed1989

[Structure and function of the "neosynovial membrane." Light and transmission electron microscopy studies of regenerated synovial membranes following surgical synovectomy].

Regenerating synovium from seven patients was examined by light- and transmission electron microscopy. Superficial layers of the "neosynovium" are composed of histocytes, fibroblasts and intermedium cells, developing out of undifferentiated mesenchymal perivascular connective tissue cells. There is no closed cell-layer, as known from mesothelia, endothelia and epithelia. Our results are similar to those of normal synovium and the so-called "pseudo-synovium" of pseudarthroses. So superficial layers of these tissues are comparable specialized connective tissues. According to experimental results in animals, in patients there will develop a "neosynovium" comparable to the original synovium in structure and function. These results confirm synovectomy as a possible operative treatment in patients.

Arthritis, Rheumatoid↗
PubMed1988

[Synovitis of the wrist joint following silicone replacement of the carpal bones].

The authors report on six patients in whom an aggressive synovitis of the wrist and erosion of the adjacent bones has developed after insertion of Silastic implants in the region of the carpus. Systemic disease, dislocation or fracture of the prosthesis was not present. In surgical revision, the prosthesis shows changes in form and rough surfaces. The synovial membrane is massively thickened and highly inflamed with pannus formation; the adjacent bone showed cartilage loss and fragmentations. Light and electron microscopic investigations of the synovial membrane and the bone show giant cells with silicone particles. We consider that compression, shearing forces as well as abnormal movements are to be considered primarily as causes of attrition. Other factors such as age, profession and location hardly play any role. Prostheses which are too large, the presence of osteophytes and structural loosening of the carpal bones are avoidable risks. After removal of the prosthesis and the synovial membrane, there is rapid healing. Subsequent arthrodesis also heals without problems.

Adult↗
PubMed1987

Cytokeratins in certain endothelial and smooth muscle cells of two taxonomically distant vertebrate species, Xenopus laevis and man.

Using immunolocalization techniques, electron microscopy, and gel electrophoresis combined with immunoblotting, we have noted remarkable interspecies differences in the expression of cytokeratins in certain nonepithelial cells. In the present study we describe, in two taxonomically distant vertebrate species, the African clawed toad Xenopus laevis and man, endothelial and smooth muscle cells which express cytokeratin intermediate filaments (IFs), in addition to vimentin and/or desmin IFs. In Xenopus, all endothelia seem to produce both vimentin and cytokeratin IFs. As well, certain smooth muscle bundles located in the periphery of the walls of the esophagus and the urinary bladder produce small amounts of cytokeratin IFs in addition to IFs containing vimentin or desmin or both. The amphibian equivalents of human cytokeratins 8 and 18 have been identified in these nonepithelial tissues. In human endothelial cells, immunocytochemical reactions with certain cytokeratin antibodies are restricted to a rare subset of blood vessels. Vessels of this type were first noted in synovial and submucosal tissues, but also occur in some other locations. Cytokeratins have also been detected in certain groups of smooth muscles, such as those present in the walls of some blood vessels in synovial tissue and umbilical cord. Here, the synthesis of low levels of cytokeratins 8 and 18, sometimes with traces of cytokeratin 19, has been demonstrated in smooth muscle cells by colocalization with myogenic marker proteins, such as desmin and/or the smooth-muscle-specific isoform of alpha-actin. Possible reasons for the differences in cytokeratin expression between adjacent endothelia in man, and smooth-muscle structures in both species, as well as biologic and histodiagnostic implications of these findings, are discussed.

Animals↗
PubMed1984

Orthopedic surgery for management of tumor pain.

Benign primary bone tumors, tumor-like lesions, and semimalignant bone tumors with pain are in most cases an indication for surgery with marginal or wide excision. In malignant primary bone tumors, the relief of pain does not have primary importance in the therapeutic concept. With en bloc resection or amputation, the cause of cancer pain is eliminated. Limb salvage procedures can be performed by endoprosthetic replacement, and phantom or stump pain will not occur. Skeletal metastases can be very painful owing to bone destruction, expansive growth, and consecutive pathologic fractures. Orthopedic surgery can relieve pain and improve the quality of life. Endoprosthetic replacement and combined osteosynthesis with PMMA and metallic implants are used to achieve early rehabilitation.

Bone Neoplasms↗
PubMed1984

[Extremity preserving interventions in malignant bone tumors].

Amputation or exarticulation are the easiest and safest ways to effect a radical cure of a malignant musculo-skeletal tumor. With progress in adjuvant chemotherapy and development of endoprosthetic devices tumor resections became more important for limb salvage procedures. Competitive surgical techniques for curative treatment always require radical tumor elimination.

Arm↗
PubMed1984

[Pathological fracture of the proximal femur and its therapy].

"Pathologic fracture" is understood as a discontinuity of pathologic bone caused by normal mechanical stress without adequate trauma. The pathologic condition of bone causing mechanical instability may be a general osteopathia (osteoporosis, osteomalacia, fibrous dysplasia, Paget's disease) or as well a localized one (primary or secondary bone tumors, tumor-like lesions, osteomyelitis). Following "pathologic fracture" pain and functional deficiency are severe, so besides diagnosis and treatment of basic disease conservative and often operative treatment of the pathologic fracture are necessary. The different procedures are discussed in relation localisation of pathologic fracture, basic disease and age of patient.

Adult↗
PubMed1980

[Connective tissue in non-union and pseudarthrosis of long bones. Part I: Capsule of false joints in dogs (author's transl)].

Animal experiments were carried out on 28 dogs which underwent osteotomy of the femur without postoperative fixation. For systematic light- and transmission electron microscopy tissue from this area of 7 dogs was prepared. Result was a functional morphology of connective tissue. Instability of bone fragments is regarded as the most important factor in pathogenesis of pseudarthrosis. Pathologic mobility in the osteotomy area caused specific altered differentiation of local connective tissue cells, leading to a joint capsule-like formation of connective tissue. "Lining cells" to the pseudarthrotic cavity are fibroblasts and histiocyts, comparable to the "lining cells" of normal stratum synoviale. These cells are surrounded by some collagenous fibres and large amounts of amorphous ground substances. They derive means of numerous transitional forms. The capsule-like tissue formation aside the pseudarthrotic cavity is comparable to stratum synoviale of normal joints. In some of these capsule-like areas there are degenerative alterations similar to those of joint capsules in osteoarthritis.

Animals↗
PubMed1980

[Connective tissue in non-union and pseudarthrosis of long bones. Part II: cavity of false joints in dogs (author's transl)].

Pseudarthrotic cavity is surrounded by joint capsule-like connective tissue as well as by the locked-up bone ends. Macroscopic and microscopic examinations indicate instability as a traumatic factor to the surrounding tissues, leading to tears and clefts covered by fibrin and erythrocyte deposits. Below, cell-layers consisting of fibroblasts and histiocytes are formed, which become comparable to stratum synoviale of normal joint especially in areas with constant mechanical stimulus like sliding and little pressure without considerable traumatic effect. Where bone ends reach like lever-arms far into the peripseudarthrotic tissue and mechanical stress of abnormal mobility is of adequate permanent traumatic effect, vascularisation is not visible and regressive, necrobiotic alterations are predominant. In areas with presumable more pressure, with little or no vascularisation, woven cartilage-like partially calcified tissues are formed. Where osteotomized bones are pressed upon each other with instability an intensive remodeling with resorption and rebuilding of bone trabeculae is visible. Muscle interposits degenerate within the continuously injured and scarcely vasculated osteotomized area, and are replaced by tight connective tissues as well as walled-in by bone trabeculae. By reforming abundant collagenous fibres the pseudarthrosis becomes more and more tight. In this way there is a reduction of the functional stimulus abnormal mobility, which induces the local connective tissue to differentiate into joint-like structures, comparable to a mechanism of "self-limitation". One animal was observed up to 48 months after osteotomy. Without therapeutic immobilisation bony consolidation and corticalisation was present in the former pseudarthrotic region, joint capsule-like tissues were no more demonstrable.

Animals↗
PubMed1980

[Connective tissue in non-union and pseudarthrosis of long bones. Part III: comparative examination of human false joints (author's transl)].

Nontreatment of far dislocated fractures of long bones is seldom, fortunately. In comparison to our animal experiments tissue samples from only one patient with similar conditions could be examined by light- and transmission electron microscopy. Microscopic findings are similar to those of animal experiments. Pathologic pseudarthrotic conditions caused by abnormal mobility can be taken as a model for observing reformation of connective tissue. In general tissue dynamics are the same as those known from the ontogeny of connective tissue. The influence of abnormal mobility to pseudarthrosis formation is discussed.

Aged↗
PubMed1980

[A morphologic contribution to the pathogenesis of psoriatic arthritis (author's transl)].

Examination by light- and transmission electron microscopy of synovial tissues from 11 patients with psoriatic arthritis revealed several morphologic pictures. Besides the previously well described zones of fibrosis and degeneration of superficial cells, now the following were shown: 1. vascular alterations, especially of endotheliocytes, 2. transitional forms among endotheliocytes, perivascular cells, and fibroblasts as well as 3. lymphoidfollice-like accumulations of round cells. These changes could indicate the presence of an exogenous agent with perhaps strong antigenic effect but in low concentration. Such findings could be interpreted as indicating that in psoriasis there is an immunologic process in stratum synoviale which leads through abnormal cell proliferation and fibrosis to the final destructive event, osterarthritis and ankylosis.

Arthritis↗
PubMedDate not supplied

[Are pathohistological studies helpful in the clinical differential diagnosis of chronic arthritis?].

We have evaluated the diagnostic and therapeutic consequences of histopathological examinations of knee synovium from 216 patients with chronic arthropathies. We were able to differentiate between non-rheumatic etiologies, such as tuberculous arthritis, villonodular synovitis, crystal arthropathies and chondromatosis. This resulted in the establishment of a diagnosis and often a guide to therapy as well. It is rarely possible however to conclusively differentiate among the different inflammatory rheumatic diseases or osteo-arthroses by the histopathology of the joint lesions seen.

Arthritis↗
PubMedDate not supplied

[Limb-saving resection procedures in primary malignant bone tumors].

Thoroughly indicated and performed limb salvaging resections of primary malignant bone tumors can be as well affective as amputations and disarticulations. Possible limb salvaging operative procedures are described with regard to histodiagnosis grading, localisation, expansion of neoplasma as well as to the personality of the patient.

Adolescent↗
PubMedDate not supplied

[Transposition of the medial meniscus as an anterior cruciate ligament replacement in animal experiments].

In 24 rabbits the anterior cruciate ligament was resected and replaced with the medial meniscus. The posterior and middle part of the meniscus was dissected from the capsule. The anterior horn remained in biological fixation. The posterior horn was fixed with a wire under tension and placed in a drill hole through the lateral femoral condyle. After 6 weeks, 3 months and 6 months the ligamentous replacement was examined. Colour and strength of the transplanted meniscus was related to tension of the cruciate ligament replacement. The transformation in ligamentous tissue could be shown histologically. According to tensile strength in the cruciate ligament fibrous cartilage tissue was replaced by parallel collagenous tissue. The intraarticular surface of the new ligament was covered with a layer of synovial cells. Boney insertion showed collagen fibers inserted in new bone formation. Metaplasia of fibrous cartilage tissue into ligamentous structures is possible under tensile strength. Autologous menisci should be preserved whenever possible. In the future allogenic menisci wight be used for cruciate ligament replacement.

Animals↗
PubMedDate not supplied

[Ender nailing of per and subtrochanteric fractures. Results and complications].

An evaluation of 84 trochanteric and subtrochanteric fractures, treated with Ender pins in the Department of Orthopaedic Surgery (University of Heidelberg) proved to be of instant success in 66 (78%) cases. A reoperation had to be performed in 10 (12%) cases, in 3 of these reoperation the pins had to be redriven. The use of Ender pins failed in 7 patients, a total hip arhtroplasty became necessary. The mortality was 14%. A third of the cases showed an external malrotation which, however, is of no relevance in older people. The intermedullary fixation with Ender pins is a useful operative procedure. Stable internal fixation can be achieved even in sever trochanteric ans subtrochanteric fractures. In case the form of the fracture, the age and the general condition of the patient are satisfactory, a total hip arthroplasty should be considered.

Adult↗
PubMedDate not supplied

[Carbon band implants in animal experiments. Light and transmission electron microscopy studies of biocompatibility].

Part of the patella ligament was resected in rabbits and replaced by carbon fibre implants. After 1, 2, 3, 6 weeks, 3 and 12 months carbon implants with surrounding tissues as well as iliac lymph nodes were removed and examined by light- and transmission electron microscopy. Of special interest were the questions whether the carbon fibre implant, will be removed by phagocytosis and substituted by a new ligament or a adequate repair tissue? Our light- and transmission electron microscopic studies give no indication of successful removal of carbon fibres by phagocytosis. The carbon fibre implant was surrounded by dense connective tissue like a scar. In deep layers of the carbon implant was no vital dense or regular connective tissue, even not after 3 and 12 months. There is no replacement of the carbon fibre implant by a new ligament or tendon but a persistent foreign body reaction. With regard to these results it is very doubtful if good late results with ligament and tendon replacement by carbon fibre implants can be expected in patients.

Animals↗