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Biomedical subjects

G Muhr

Publications and source records attributed to G Muhr.

At least 91 records · Page 5Linked to original sources
PubMed2001

How risky is early intramedullary nailing of femoral fractures in polytraumatized patients?

There is controversy over both the time of intervention and the technique of surgical stabilisation of femoral fractures in polytraumatized patients. Retrospective analysis of data on 55 such patients revealed that stabilisation within the first 24 h using locked, unreamed nails had no negative impact on the rate of pulmonary complications. The frequency of complications was assessed by comparing immediate intramedullary (IM) osteosynthesis with extramedullary stabilisation in patients with or without concomitant blunt thoracic trauma. Due to the small study population and discrepancies the size of subgroups, no definite statistical conclusions were possible. However, our results suggest that the frequency of complications is determined by the overall severity of injury rather than by the type of acute surgical treatment.

Adolescent↗
PubMed2001

Decreased leukotriene release from neutrophils after severe trauma: role of immature cells.

Polymorphonuclear granulocytes (PMN) play a key role in host defense against microbial infections. After severe trauma PMN show cellular dysfunctions including chemotactic migration, phagocytosis, and bacterial killing. In these settings the contribution of the cellular maturation stage compared to functional activities has not been investigated. Polymorphonuclear granulocytes are potent producers of lipid mediators via the 5-lipoxygenase (5-LO) pathway (leukotrienes, LTs) which exert important proinflammatory and immunoregulatory activities. We analyzed leukotriene generation from PMN-fractions (N = 23) of 15 polytrauma patients in comparison to 17 healthy donor cell fractions and correlated this lipid mediator release to the hematopoietic maturation stage of respective PMN. Polymorphonuclear granulocytes were isolated from EDTA-anticoagulated peripheral blood employing a one step procedure based on a discontinuous double Ficoll-gradient. Cells (5 x 10(6)/500 microl phosphate-buffered saline) were stimulated for 20 min at 37 degrees C with 1 microM Ca-ionophor A23187 in the presence of 1 mM Ca++ and 0.5 mM Mg++. Leukotrienes were analyzed by reversed-phase HPLC. Expression of 5-lipoxygenase (5-LO) was additionally determined by Western blot. Maturation stage of PMN was quantitated by Pappenheim-staining of cell smears. After polytrauma the generation of leukotrienes from PMN was individually diminished. Synthesis of enzymatically formed metabolites (LTB4, OH-LTB4 and COOH-LTB4) was concomitantly reduced. The decresaed leukotriene synthesis strongly correlated (r2 = 0.907, P < 0.0001) to the occurrence of immature PMN (mostly band cells). The expression of 5-lipoxygenase in PMN fractions consisting mainly of band cells was decreased. Our results provide evidence that posttraumatic granulocyte dysfunction is partly due to immature functional cell capacities.

Adolescent↗
PubMed2001

Influence of low molecular weight heparin (certoparin) and unfractionated heparin on the release of cytokines from human leukocytes.

We analyzed the influence of heparins (unfractionated heparin, UFH and low molecular weight heparin certoparin) on the generation of IL-1ra, IL-6, IL-10, and IL-12p40 and from leukocyte fractions in vitro. Polymorphonuclear neutrophil leukocytes (PMN) and peripheral blood mononuclear cells (PBMC) from 16 different healthy donors were isolated and adjusted to 1 x 10(6) cells/ml supplemented RPMI 1640. Leukocyte fractions were differentially stimulated (PMN with 1 microg and 5 microg LPS, PBMC with 10 ng TSST- 1 or 2 microg ConA) in the presence or absence of heparins (1 U/ml, 2 U/ml, and 4 U/ml) for 24 h at 37 degrees C. Cytokine release was analyzed by ELISA. Certoparin but not UFH led to a dose-dependent increase in IL-6 from non-stimulated PBMC. In contrast, the release of IL-1ra, IL-10, and IL-12p40 was not modulated by heparins in a dose-dependent fashion. Increases in these cytokines occurred only as single incidents at intermediate heparin levels. An influence of the heparins on the apoptosis of PMN (measured as DNA-fragmentation in non-stimulated or LPS-stimulated cell-fractions) was not observed.

Cytokines↗
PubMed2001

Analysis of TGFbeta3 gene expression and protein levels in human bone and serum.

Recent data indicate that TGFbeta3, one member of the TGFbeta-isoforms, has an important role in bone remodeling. Up to date little is known about the expression and regulation of TGFbeta3 in man. We established a highly specific ELISA for quantitative measurement of TGFbeta3 in bone and blood samples and a RT-PCR in combination with HPLC for detection and quantification of TGFbeta3 mRNA in 89 human bone samples. Levels of TGFbeta3 protein ranged between 30 and 66 pg/mg bone (mean 36,6 +/-1,03 pg/mg) and between 30 and 1910 pg/ml in serum (mean 128.9+/-38.9 pg/ml). TGFbeta3 mRNA expression as well as protein levels in serum and in bone declined age dependently. No specific load- or site-specific distribution of TGFbeta3 mRNA expression or protein content was detected at different sites indicating an absence of mechanical regulation. Protein levels of TGFbeta3 in serum correlated with TGFbeta3 mRNA expression in bone (p= 0.0027; r=0.49). By contrast, TGFbeta3 protein levels stored in the bone matrix were not related to TGFbeta3 mRNA reflecting the long term process of TGFbeta3 deposition during bone remodeling. Notably TGFbeta3 serum levels were highly correlated with IGF-I and osteocalcin levels in serum. We conclude that TGFbeta3 in man circulates in significant amounts which appears to be representative for TGFbeta3 expression in bone tissue and may be in part derived from bone. The high correlation of TGFbeta3 with IGF-I suggests parallel systemic principles of regulation.

Adolescent↗
PubMed2001

TGFbeta1 and TGFbeta2 mRNA and protein expression in human bone samples.

Transforming growth factor beta is one of the most abundant growth factors stored in bone. It is known as a potent regulator of osteoblast proliferation and differentiation as well as of production extracellular matrix. We established a highly specific RT-PCR in combination with HPLC for detection and quantification of TGFbeta1 and TGFbeta2 mRNA expression in 89 human bone samples. Levels of TGFbeta1 protein ranged between 27 and 580 ng/g bone (mean 188 +/- 15 ng/g; n=75) and for TGFbeta2 between 7.2 and 35 ng/g bone (mean 14.3 +/- 2.1 ng/g; n=57). TGFbeta1 and TGFbeta2 protein concentrations and TGFbeta isoform mRNA expression in bone were not significantly different between the sexes. TGFbeta isoform mRNA expression as well as protein content in bone declined age dependently. TGFbeta1 and TGFbeta2 protein and mRNA expression were different in bone samples from different sites of the skeleton indicating in part the regulation by mechanical stimuli. In contrast to TGFbeta1, TGFbeta2 mRNA expression was significantly enhanced in osteoarthritic bone compared to unaffected bone. These data are in concordance to previous results concerning the expression of TGFbeta3 in bone. In conclusion, the data suggest distinct patterns' of expression of the TGFbeta isoforms under physiological and pathological conditions in bone.

Adolescent↗
PubMed2001

[Complications in the use of the halo fixator].

50 patients out of a total of 88 who underwent treatment using a halo-fixateur between 1987 and 1997 were available for a follow-up interview reviewing local complications and quality of life. Marginal discomfort was observed in 54% of patients, moderate complaints/transitory pain in 30%, prolonged and severe discomfort and pain in 16%. 62% of patients took no analgetics, 22% infrequently, and 16% continuously throughout treatment. In pin-tract infection local treatment was successful in 6 patients, in 3 patients the screws needed to be relocated. Complaints of dysphagia due to extended forced lordosis of the cervical spine could be corrected by adjusting the position of the halo ring in 3 out of 8 patients. 3 patients developed pressure sores which could be managed without surgical intervention. Proper fixation and placement of the pin-tracts are crucial in the application of the halo fixateur if complications are to be avoided. Superficial infections must be treated locally. If the infection persists immediate pin relocation and systemic antibiotic therapy have to be initiated.

Adolescent↗
PubMed2001

Osteoid osteoma that occurred in a former fracture site.

Diagnosis of osteoid osteoma often is delayed, despite its high incidence, because of similarities in presenting symptoms with other pathologic entities. The current case report describes a posttraumatic osteoid osteoma. Three years after osteosynthesis of a distal tibial fracture an osteoid osteoma was diagnosed at the former fracture site. After excluding osteomyelitis as a possible diagnosis, the tumor was excised successfully. Based on current knowledge of the pathogenesis of osteoid osteoma, it is unlikely that the lesion observed in the patient was attributable to the previous fracture.

Adolescent↗
PubMed2001

[Long-term results after resection arthroplasty according to Girdlestone for treatment of persisting infections of the hip joint].

INTRODUCTION: Persisting infections of the hip joint are regarded as one of the most feared complications following total hip arthroplasty or failed osteosynthetic treatment of fractures of the proximal femoral part. In these cases resection arthroplasty according to Girdlestone often is the ultimate treatment. METHODS: Twenty-seven patients (11 men and 16 women) who had undergone resection arthroplasty according to Girdlestone could be included in this study. In all cases Girdlestone operations had been performed because of persisting infections of the hip joint. The mean follow-up was 7.1 years. RESULTS: In 22 out of 27 cases (81.5%) eradication of the infection was finally achieved. At the time of re-evaluation 6 patients had no pain, 12 sometimes suffered from moderate pain, 7 from pain during physical activities and 2 patients experienced pain even at rest. At the time of follow-up, 11 patients used a cane, 14 patients needed two canes or crutches and in 2 cases a wheelchair was necessary. The mean shortening of the leg was 5.2 cm (range 3-15 cm). Clinical evaluation using the score according to Merle d'Aubigné and Postel to assess the functional results showed a mean of 6.7 points (range 2-10 points). Of our patients, 59.3 % were satisfied with the functional results obtained. CONCLUSION: In the long run the Girdlestone procedure still seems to be a reasonable salvage operation for persisting deep infections following hip surgery.

Activities of Daily Living↗
PubMed2001

[Osteogenetic activity of BMP-3-coated titanium specimens of different surface texture at the orthotopic implant bed of giant rabbits].

INTRODUCTION: The successful combination of osteoinductive factors with current materials used in both endoprosthetics and implantology improves bony ingrowth and long-term stability of the chosen implants. The aim of the present experimental animal study was to clarify in what way faster bony integration can be achieved through additional BMP-3-coating of titanium test implants of different surface textures (hydroxy-apatite-coated or corundum-blasted). METHODS: Thirty of 60 cylindrical titanium test implants with a hydroxy-apatite or corundum-blasted surface were coated with 230 microg porcine, high-purified BMP-3-precipitate per implant to check their osteoinductive potential in a bioassay. In each case a BMP-3-coated and an uncoated control-device were implanted with a gap formation of 1 mm into the femoral part of the patellofemoral joint of the right and left leg of 30 adult giant rabbits. Serial saw slices of all explanted specimens were prepared, and the osseous integration of the implant and time-dependent bone neoformation were analyzed microscopically and histomorphometrically 14, 35, and 56 days after implantation. RESULTS: Coating of TiAl4V6-test devices with BMP-3 led in both groups after gap implantation to an improved osseointegration, that was histomorphological and histomorphometrical verifiable. Statistical evaluation using the t-test for matched samples showed 5 weeks after surgery a significant higher volume of new formed bone of the BMP-3-coated corundum-blasted or hydroxy-apatite-coated TiAl4V6 test devices compared to the non-coated controls of the same type (P < 0.01). Light microscopy demonstrated osseointegration without connective tissue membrane around the surface of the implants after 2, 5, and 8 weeks. Better osseointegration was achieved in the hydroxy-apatite-coated implants than in the corundum-blasted implants. CONCLUSIONS: Our results indicate that composite metal implants, as used in endoprosthetics and implantology, are suitable carriers for BMP-3 and improved fixation of the implants can be achieved.

Alloys↗
PubMed2000

The potential pattern of circulating lymphocytes TH1/TH2 is not altered after multiple injuries.

HYPOTHESIS: A shift in the balance of helper T cells type 1 (T(H)1) toward type 2 (T(H)2) has been suggested as a possible mechanism for impaired immune responses after severe trauma. We suggest that major injuries (polytrauma) induce an alteration in the pattern of T(H)1/T(H)2 cells. DESIGN, SETTING, AND PATIENTS: A prospective study of 35 polytraumatized patients (Injury Severity Score >16) admitted to a trauma intensive care unit at a level I trauma center (university hospital). INTERVENTIONS: Blood samples were collected from patients at various times during their stay in the intensive care unit and from age- and sex-matched healthy individuals. MAIN OUTCOME MEASURES: Serial determinations (n = 81) of intracellular interleukin (IL)-2 (T(H)1 cells) and IL-4 (T(H)2 cells) in stimulated CD3(+) T cells from patients with polytrauma twice a week during their stay in the intensive care unit accompanied by determination of the cell activation marker CD69 using 3-color flow cytometry. In parallel, the release of IL-2 and IL-4 from stimulated peripheral blood mononuclear cells and systemic plasma IL-4 levels were analyzed by conventional enzyme-linked immunosorbant assay. Healthy donors (n = 53) served as the control group. Data were related to outcome, Injury Severity Scores, and time after trauma. RESULTS: Expression of the cell activation marker CD69 was similar in stimulated lymphocytes from patients and healthy donors. There were no significant posttraumatic alterations in numbers of CD3(+) cells stained for intracellular IL-2 or IL-4, except for a minor decrease in IL-2(+) cells during the first week after trauma. Subgroups with high (>24) and lower (<25) Injury Severity Scores or survivors and nonsurvivors revealed no differences in intracellular cytokine staining. In contrast, patients revealed a highly significant decrease in the number of CD3(+) T cells. Mean systemic IL-4 levels did not differ in patients compared with healthy donors. Release of IL-2 and IL-4 from peripheral blood mononuclear cell fractions stimulated with phorbolmyristateacetate and ionomycin was significantly increased in patients with trauma but not from those stimulated with toxic shock syndrome toxin-1. CONCLUSIONS: Patients with multiple injuries have no significant alteration in the ratio of circulating T(H)1/T(H)2 cells. Thus, our results suggest pathomechanisms in posttraumatic T-cell suppression apart from alterations in the T(H)1/T(H)2 pattern.

Antigens, CD↗
PubMed2000

[Diaphyseal femur pseudarthroses--only a technical problem?].

Between 1981 and 1994 at the Bergmannsheil Ruhr University Hospital in Bochum, Germany, we treated 145 patients with femoral diaphyseal nonunions following initial operative treatment. Of these patients, 138 received this initial operative treatment at an outside institution. The primary reconstructions for the fractures utilized plates in 112 cases, reamed nails in 24 cases and external fixators in 9 cases. The average age of the patients was 35 years and the mean time from the initial operative treatment was 2 years. Twenty-seven patients (19%) presented with a hypertrophic nonunion and 118 (81%) with an atrophic nonunion. There was a significant correlation between primary "classic" plating and development of an atrophic nonunion (chi 2-test: P < 0.01). We observed 34 wound infections (23%) with no significant correlation to the type of primary osteosynthesis. We determined that 73 of the pseudarthroses were due to improper osteosynthesis techniques. Of these cases, 41% involved the use of plates, 83% involved the use of reamed nails, and 78% involved the use of external fixators. Fracture location near the diaphyseal-metaphyseal junctions was common in this problematic group. Ninety-two percent of all plates led to atrophic nonunions. There were 21 open fractures and of these 90% (n = 19) developed an atrophic pseudarthrosis and 29% (n = 6) developed a wound infection. Fifty-seven (39%) of all patients had additional injuries, but we found that did not increase the risk of disturbed bone healing. Our revision operations focused on the elimination of wound infections, refreshment of bone healing, and improvement in fragment stability. Only 28% of all "classic" plates and 11% of all external fixators were changed to an intramedullary implant at the time of the first revision surgery. Hypertrophic nonunions required a mean of 1.3 revision operations to achieve bone healing whereas a mean of 2 revision operations were necessary to fuse atrophic bone ends (P < 0.05). In cases of diaphyseal pseudarthrosis healing time was not affected by the type of osteosynthesis used for primary reconstructions. Since lack of fracture healing can often already be observed directly from postoperative X-rays, we recommend that revision procedures be performed early. The prolonged length of time to care for femoral nonunions underlines the importance of appropriate primary fracture treatment. That takes into consideration both the biomechanical and the biological aspects of bone healing.

Adolescent↗
PubMed2000

[Chronic venous insufficiency after open tibial fracture. An underestimated problem].

There is a wide range of alternatives for primary bone reconstruction in the treatment of open lower leg fractures with soft tissue damage of the type Gustillo II and III. The primary objective should always be the protection of soft tissue damage whether one uses the fixateur externe, or an unreamed nail or primary bone shortening with secondary callus distraction. In recent years, this approach has produced better results and a reduction in the rate of major amputations. The overall effects of the initial treatment can only be analysed after a number of years. Research results indicate long-term soft tissue complications of the lower leg, varying from harmless swelling to venous ulcer. We conducted a clinical investigation which compared 80 patients, who were treated between 1985 and 1994 using the venous-occlusion plethysmography, to 50 healthy individuals. Clinically significant damage of the deep venous system was found in over 50% of cases. There was a direct correlation between the number of years since the initial treatment and the degree of damage found. Based on these findings, we recommend that the initial treatment of this condition and the preventative treatment of the secondary trauma diseases should follow regulated surgical guidelines and be recognised for insurance purposes.

Adult↗
PubMed2000

[Does liberation of interleukin-12 correlate with the clinical course of polytraumatized patients?].

INTRODUCTION: Interleukin-12-p70 (IL-12-p70) is a potent immunoregulatory cytokine composed of a heavy chain (p40) and a light chain (p35). Contradicting results have been reported with regard to leukocyte release and systemic concentration of IL-12 after polytrauma. METHODS: We daily analyzed systemic concentrations of IL-12 in polytrauma patients (n = 37, mean ISS 33.9) in comparison to healthy donor values during intensive care course by ELISA. Patients were divided according to their mean IL-12 levels into those with elevated IL-12 (group 1, n = 7), those with decreased IL-12 (group 2, n = 4) and those with IL-12 in the normal range (group 3, n = 26). RESULTS: Patients in group 1 revealed elevated levels of IL-12 up to p70 > 1000 pg/ml and p40 > 2500 pg/ml. The common clinical feature of group 1 was a thorax trauma in combination with pneumonia (85% survivors). Patients with single thorax trauma or pneumonia without thorax trauma (group 3) showed normal IL-12 values. Patients with decreased IL-12 levels revealed also a thorax trauma and pneumonia but all patients succumbed. The groups significantly differ in their stay in the intensive care unit, in TISS, in MODS score and in respiratory ratio, but not in ISS, mean CRP values and leukocyte counts. Correlation analysis revealed no significant relation between systemically altered IL-12 values and clinical parameters, with the exception of a negative correlation of p70 and ISS (r = -0.785) or MODS score (r = -0.314) in group 1. CONCLUSIONS: After major injuries there is no overall suppression of IL-12 formation. Patients with normal or elevated IL-12 levels belong mainly to the survivors, whereas patients with decreased IL-12 levels are at high risk of succumbing to multi-organ failure.

Adolescent↗
PubMed2000

[Anterior screw fixation for odontoid fractures].

The results of anterior screw fixation of odontoid fractures in 28 patients are presented. There were 27 type II- and 1 type III-injuries. Non-union with persistent instability had to be notified in one patient (3.6 %), secondary posterior C1/2 fusion had to be performed. Incorrect positioning of the screws in the odontoid with penetration of the postero-lateral cortex occurred in 3 patients (10.7 %). Malpositioning of the odontoid after screw fixation was documented in 5 cases (17.9 %). Cardiopulmonary complications had to be treated in 5 patients (17.9 %), 4 patients (14.3 %) died in the postoperative period. 17 patients could be followed up. Only 3 patients (17.8 %) were free of symptoms. A significant limitation in ROM of axial rotation was seen in 44 % of the patients. With anterior screw fixation of the odontoid high fusion rates can be achieved, however the procedure is technically demanding. Regarding the functional outcome, there is no significant difference to other established treatment methods.

Adolescent↗
PubMed2000

[Intrathoracic displacement of the transverse colon as a late complication after abdominal knife stab wound. A case report].

The treatment of stab wounds of the abdomen is discussed controversely. The management of these wounds depends on a high degree on the clinical situation of the patient. Repeated physical examination, peritoneal lavage and laparotomy are recommended. The identification of an isolated diaphragmatic injury is worrisome because its subtle clinical presentation is often not alleviated by adjunctive tests. Delayed recognition of an incarcerated diaphragmatic hernia has a high mortality rate. We report about an 23 year old African male, who was injured by an intraabdominal stab wound. Initially he did not have any clinical problems, but after 6 months he was admitted to the hospital due to severe pulmonary complications. A diaphragmatic hernia with dislocation of the transverse colon into the left thorax was identified on x-rays. A thoracotomy as well as a laparotomy were performed to restore the anatomic conditions and to dose the hernia. After two weeks, the patient could leave the hospital without pulmonary complications. Under consideration of the literature we recommend exploratory laparotomy for stab wounds that penetrate the left side of the chest below the fourth intercostal space anteriorly, the sixth intercostal space laterally and the tip of the scapula posteriorly. The high mortality rate after a delayed recognition appears to justify an early operative approach.

Abdominal Injuries↗
PubMed2000

[Acute pseudo-obstruction of the colon as complication of hip surgery].

Pseudo-obstruction of the colon is characterized by a massive colonic dilatation without mechanical obstruction. It is rarely after hip surgery, however, untreated it may be complicated by a life threatening perforation of the colon. In a retrospective analysis we reviewed 11 patients (4 women, 7 men, mean age 75.2 years, range 67 to 86 years) with pseudo-obstruction of the colon after hip surgery in the years 1995 to 1998. In relation to all patients aged 65 years and older who underwent surgery of the hip, the prevalence was 1.06%. The leading clinical symptom was abdominal distension. On plain x-rays, dilatation of the colon measured 13.3 cm on average (9-16 cm). In two patients (18%) adequate application of drugs stimulating the gastro-intestinal motility was sufficient, whereas in 8 patients (73%) colonoscopic decompression had to be performed. In three of these, the procedure failed and because of persistent symptoms a cecostomy was performed. One patient underwent immediate laparotomy because of peritonitis. 2 patients (18%) died because of a complicated course. Non operative treatment should not exceed 24 hours, endoscopic decompression and tube placement is considered as the treatment of choice. In cases of failure of these procedures, perforation of the colon and/or peritonism, urgent laparotomy with open decompression by a cecostomy is essential.

Acute Disease↗