Biomedical subjects
Publications and source records attributed to I Michiels.
Emergency caesarean section was performed in a 40-year-old woman with solutio placentae. A Couvelaire uterus was diagnosed, showing typical blue-purple discolorations of the uterine wall, which are in fact haemorrhages caused by disseminated intravascular coagulation.
The purpose of this study was to evaluate the efficacy of three screening tests in detecting glaucoma in its early stage: the Tendency Oriented Perimetry (TOP) and Frequency Doubling Perimetry (FDP) visual field tests, and the Glaucoma Diagnostic (GDx) nerve fibre layer analyser. Eighteen patients with glaucoma who showed an early defect on HFA c 24-2 and twenty normals underwent the three tests. TOP showed a sensitivity of 94.4% and a specificity of 75%, FDP showed a sensitivity of 72.2% and a specificity of 100%, and GDx a sensitivity of 77.7% and a specificity of 60%.
During a Magnetic Resonance sequence, simultaneously acquired ElectroEncephaloGraphy (EEG) data are compromised by severe pollution due to artifacts originating from the switching of the magnetic field gradients. In this work, it is shown how these artifacts can be strongly reduced or even removed through application of an adaptive artifact restoration scheme. The method has proved to be fully automatic and to retain high frequency EEG information, which is indispensable for many EEG applications.
In this paper the kinematics of arm abduction in the scapular plane of 38 healthy experimental subjects is reported. The ratio of the glenohumoral and the scapulothoracic components of the motion were determined and the influence of the abduction speed and of the external load on it were investigated. The investigation of the effect of abduction speed involved all 38 subjects. Each of them performed one slow and one fast abduction. Statistical analysis showed that there were large differences between individuals, but that for any one individual the abduction process is essentially reproducible. For the one individual there is a strong, linear relationship between glenohumeral and scapulothoracic rotation. The slope of the regression of the glenohumeral component on total arm abduction varied from 0.75 to 0.5 with a sample mean of 0.66. It means that only two-thirds of arm abduction occurs in the glenohumeral joint, the remaining third taking place via scapular rotation. In slowly performed abductions the slope of the regression was significantly greater than in the high-speed movements, but differences were very small. In the investigation of the effect of external load, statistical analysis indicated that the slope of the intraindividual regression is largely independent of the load. The possibility of observer bias was analysed, too. It was found that the standard deviation of the abduction parameters determined by different observers was between 6 and 10% of that between different experimental subjects. RELEVANCE: A knowledge of the kinematics of the shoulder joint is necessary to understand subacromial pathology and in particular impingement problems. The scapulohumeral rhythm depends on the balanced and coordinated function of the muscles involved. The activation pattern of the abductor muscles, as reflected in shoulder kinematics, seems to be individual and stored as an engram.
The distribution of endogenous lectins, visualized by labelled neoglycoproteins, and of defined oligosaccharide structures, reactive with plant lectins, during fetal development of the fingers was analyzed in sections of human 3- to 8-month-old fetal specimens. Chondrogenesis as well as ossification were correlated with characteristic modulations in the expression of both glycoligand-binding molecules and characteristic carbohydrate structures. Occurrence of xylose-specific receptors was judged to be an early sign of cartilage development. Similarly, alpha-mannosyl residues that had been attached to labelled carrier proteins were strongly bound by the extracellular matrix already during early stages of finger maturation. Staining intensity for heparin gradually increased during chondrogenesis, whereas affinity for mannose showed a stage-related decline. Binding of mannose-6-phosphate was confined to hypertrophied cartilage of primary ossification centers. Accessible binding sites for terminal N-acetylneuraminic acid and N-acetylgalactosamine moieties were detected only in osteoid. In addition to monitoring the sugar-binding capacity, presence and developmental regulation of distinct carbohydrate structures were also assessed. PSA and SBA enabled the demonstration of an abrupt loss of staining affinity in the zone of maturing hypertrophic cartilage. Succinylated WGA proved to be an apparently useful marker of evolving bone tissue. GSL-II binding was restricted to chondroclasts and osteoclasts. The findings of this investigation are consistent with the supposed role of glycoconjugate-lectin interactions in cartilage and bone development.
In our laboratory for biomechanics, a new isolation amplifier was developed with which to record the electromyographic activity of muscles inaccessible to surface electrodes, in particular that of the rotator cuff. Our basic premisses were maximum safety for the patient or subject investigated, and optimal signal processing. These were achieved by a triple galvanic separation of the patient/subject from the battery power supply and the signal cables and by careful selection of the electronic components.
Isolated fractures of the Trochlea humeri are only rarely seen because in case of indirect trauma this portion of the elbow is only partially exposed to transmitted forces and in case of direct injury adjacent elements are also involved. On the lateral films a half-moon shaped fragment in front of the Humerus together with joint effusion are indicative of this type of fracture. Depending on the grade of dislocation of the fragment, which has to be shown radiologically, conservative or operative management are chosen.
Following irrigation-suction drainage and synovectomy in 68 knee joints for empyema between 1971 and 1987, all were available for clinical and radiological follow-up. Since in 24 cases the empyema occurred after total knee arthroplasty, this group of patients was evaluated separately. The mean follow-up time in the no-prosthesis group was 8.3 and that in the prosthesis group, 5.3 years. In particular the aetiological factors, the bacterial pathogens and the effect of infection on radiological signs of degeneration were studied. The clinical results, including subjective findings, were assessed with the aid of HSS score. Our late results show that the prognosis for knee joint empyema can be rated as good if it is diagnosed early and treated aggressively. The poor outcome in a few cases was rather the result of underlying local disease and concomitant factors, and seemed not to be an immediate consequence of the infection itself. The relatively poor results in prosthesis group have to be referred predominantly to cases dating from the early years of total arthroplasty, with implants of the metal-on-metal type.
We have carried out an electromyographical examination of the activity of five different regions of the deltoid muscle during abduction/adduction in various body postures with different biomechanical actions of arm gravity. The results show that the deltoid action is highly differentiated in its different regions and is not restricted only to the generation of an abducting moment in the shoulder joint. There is obviously a biomechanical contribution, mainly by its spinal and clavicular regions, to the stabilization of the glenohumeral joint and to the control of the selected plane of abduction.
Thirty-one elbow joints in 29 patients (28 males, only 1 female), operated on for osteochondritis dissecans, were available for follow-up after an average of 10 years. The mean age at diagnosis was 24.4 years, but 11 patients were younger than 20. In 23 out of 29 patients the right elbow was involved, including 2 cases with bilateral involvement. In 20 cases removing the free bodies was the only surgical procedure performed, but in 2 cases it was combined with resection of the radial head. At follow-up, only one-third of the patients had no complaints. Nevertheless, daily activity was not restricted for any of the cases. Degenerative arthritic changes were found in only a few cases. These results are illustrated by means of three typical cases, which are compared with six similar cases in the international literature.
Calcifying tendinitis of the shoulder joint is a relatively common condition. Its pathogenesis is well documented in anatomical-pathological terms. The clinical observation of four unusual locations in the upper limb makes us to suspect the same pathological process as in the supraspinatus location. The clinical course of calcifying tendinitis in a typical location is discussed in detail.
A case of septic Candida albicans arthritis of the knee in a patient with systemic candidiasis is presented. Systemic and intra-articular cellular immune responses to C albicans and various bacterial antigens were monitored for 15 weeks. It is shown that the candida induced blastogenesis of synovial fluid lymphocytes was much more stimulated than that of peripheral blood lymphocytes, and that the proportion of activated cells expressing HLA class II antigens was markedly increased in the synovial fluid. Strong cellular immune responses to Candida albicans could still be shown many weeks after the synovial fluid aspirates had become sterile. For the first time synovial fluid derived, CD4 positive T lymphocyte clones with specificity for candida antigens were characterised and further propagated in vitro.
The radiation exposure during biomechanical investigation of the shoulder joint done with a digital radiography system (Polytron 1000 VR - Siemens) was measured experimentally. Total radiation dose and surface dose were determined by phantom measurements. The radiation exposure per image is about 1/6 to 1/7 of that of a conventional study. The digital radiography system used is thus suitable for kinesiologic studies of large joints in healthy volunteers.
In this study 17 patients with recurrent dislocation of the patella were followed up 10 years after Goldthwait-operation. The subjective and clinical findings were excellent rsp. good in 70%, whereas the x-ray findings showed osteoarthritis of the femoropatellar joint in 60%. Concerning the aetiopathological factors we found an increased external torsion of the afflicted extremity measured by computed tomography.
Basing on 13 dislocations of 215 total hip arthroplasties are presented the characteristics of this complication. All things considered the dislocation following total hip arthroplasty seems to be no serious complication, if there is no severe operation failure and if the necessary treatment consisting in plastic cast immobilisation is performed.
Cartilage damage in the knee joints of rats was induced with a single intraarticular injection of 10 mg papain. Such damage was indicated by a decrease in the content of glycosaminoglycans and histologically detectable alterations in the surface of patellar cartilage. Daily treatment of the rats with N-acetylglucosamine by gavage led to an increase of the glycosaminoglycans of the cartilage and of incorporation of the radioactive precursor of glycosaminoglycan synthesis, 3H-glucosamine hydrochloride, in comparison to control animals treated with saline. The incidence of pathological alterations of the cartilage in histological samples was reduced.
Four cases of malignant synovialoma (synonym: synovial sarcoma) of the sole of the foot are reported. A striking feature of all four cases was the long delay before the final diagnosis was made. Although this condition is rare, our cases nevertheless show that chronic neuralgiform pain close to the joint should prompt consideration of this tumor in the differential diagnosis. However, even surgical revision or explorations do not always reveal the tumor.
Osteochondritis dissecans (OD) of the lateral tibial condyle is a rare condition. A review of the literature revealed only nine cases in seven patients. We report about a new case. It is widely accepted that this form of OD originates from an accessory center of ossification. Our case supports this theory. Although comparative roentgenograms of the left knee, taken because of complaints in the right one, were interpreted to be normal, retrospective analysis clearly revealed the lateral intercondylar eminence of the left knee to have been irregular many years before the onset of symptoms. Association with a classical OD in the contralateral knee is striking in most of the reported cases.