[A new plate for dorsal occipito-cervical fusion. Design, surgical technique, initial clinical results]

A survey of actually practiced methods for cranio-cervical fusion is presented, followed by the description of a new osteosynthesis-plate to solidly fuse this region. The new plate offers a number of advantages when compared with competing procedures. It is rigidly fixed to the occipital bone by five screws, sublaminar wireloops bond the vertebrae to be fused to both branches of the U-shaped plate where the individual loops are positioned into obliquely ascending slots. This safely prevents migration and disengagement resulting in a high initial horizontal and vertical stability allowing for a postoperative care without external support. During the procedure tightening of the wire loops may succeed on reposition of the deformity. The plate exists in two lengths allowing fusion of C0-C2 or more segments of the cervical spine. The typical indication is instability of C0-C2 in rheumatoid arthritis or tumoral lesions of the area. Clinical experience in 7 patients suffering from rheumatoid arthritis (follow-up: 6-31 months) is very positive, fusion has occurred in all cases.

Early surgical treatment for congenital vertical talus

Congenital vertical talus is characterised by a dislocated talonavicular joint in association with an equinus position of the calcaneus. We report the results in 13 operated feet in 10 children, 3 of whom (5 feet) presented with a primary neurological disorder and 2 of whom (3 feet) suffered from arthrogryposis multiplex congenita. The other children were normal. All patients were surgically treated by a one-stage procedure which included reduction of the talonavicular joint and correction of the hindfoot equinus, trying to avoid tendon lengthenings and transfers. The age at operation was between the 3rd and the 6th month of life, with one child being operated on later due to other reasons. The patients were reviewed after an average time of 3.5 +/- 2.2 years. The clinical results were good or excellent in ten feet. Two feet showed partial or complete recurrence and one foot was slightly over-corrected. Radiographic angle measurements (talo-metatarsal I angle and talocalcaneal angle on the anteroposterior radiograph; talocalcaneal, tibiotalar and tibiocalcaneal angles on the lateral radiograph) returned to normal values in the ten good or excellent feet. Early operative treatment for congenital pes vertical talus leads to very satisfactory functional and cosmetic results, usually avoiding extensive procedures including tendon lengthenings and tendon transfers.

[Diagnosis and therapy of coxitis fugax with special reference to the value of ultrasonographY-assisted diagnosis and hip joint puncture]

Between 1984 to 1991 55 children (mean age 7.0 years) were observed with a painful effusion of the hip examined by ultrasound. Children with radiologically diagnosed hip diseases were excluded. In 47 cases we found a transient synovitis of the hip which started at an average interval of 4 days in mean before admission. All children were reexamined 6 weeks after the end of treatment sonographically and clinically, 4 of those revealing incipient Perthes diseases. The primary sonographic right/left difference in amount of effusion (mean) was 4.0 +/- 1.7 mm and after aspiration 1.5 +/- 1.4 mm with a significantly correlation with the amount of aspirated synovial fluid. The radiological findings for a diagnosis of an effusion of the hip were not reliable. Beside the diagnostic signs of the appearance of the aspirated fluid the sonographic assisted aspiration of the hip is an important treatment mode to reduce the intracapsular pressure and the pain of a hip effusion in children.

The influence of physical fitness on automatic and effortful memory changes in aging

A cross-sectional study was carried out in order to determine the influence of cardiovascular fitness on age-related declines in cognitive performance. Forty-eight volunteers were divided into Young (n = 13, 18-27 years), Middle-Aged (n = 22, 60-65 years) and Old (n = 13, 65-88 years) groups and tested on a battery of cardiovascular, pulmonary, hemodynamic, and biochemical tests in order to assess physical fitness. Cognitive performance was evaluated by a variety of memory tasks distributed along an automatic-to-effortful processing continuum. Memory for location and frequency of occurrence were selected as representative of automatic processing, whereas, an auditory free-recall task was selected as representative of effortful processing. Age-related performance declines were observed for the free-recall task, but no such age-dependent association was observed for frequency and location memory. With regard to the influence of physical fitness; the Middle-Aged and Older participants were divided into High and Low Fitness groups and significant differences were observed between these groups for the effortful but not the automatic memory tasks. These data suggest that the relationship between physical fitness and cognitive performance in old age is task dependent. Furthermore, the apparent prophylactic effects of physical fitness on effortful memory, do not appear to extend to cognitive tasks requiring less effortful processing.

[Wound secretions in standard orthopedic surgery interventions using a new kind of closed vacuum drainage. A report of experiences]

One year's experience with 400 closed Redyrob drainage systems in 267 male and female patients has yielded encouraging results, which led to the replacement of the drainage system formerly used in the orthopaedic university clinic in Marburg by the new system. This makes it possible to regulate the suction strength between 0 and 900 mbar and to couple two suction tubes with one container. Drainage without suction and changing of the containers, which may be necessary in the case of large wound surfaces, can be performed without opening the system, which would endanger both patients and clinic personnel. Additional containers were only needed in 2.3%, because of the better filling volume. Thus, the new drainage system also proved to be superior with respect to cost efficiency and disposal. The total amount of wound secretion never exceeded 1620 ml, depending on the type of surgery performed, and there were no cases of infection or bleeding complications. The suction was regulated in 74% of all systems, and after most of the operations for insertion of endoprostheses. The handling of the systems was classed by the staff on the ward as "very good" or "good" in 96% of all cases. These results are discussed in the light of important aspects of wound drainage already mentioned by other authors.

[Autologous cartilage-bone transplantation in the therapy of osteochondrosis dissecans of the knee joint]

This study presents the results of twelve patients, treated by an autologous bone and cartilage transplant for an advanced stage (stage IV and V referring to Rodegerdts and Gleissner, 14) of osteochondritis dissecans of the knee. In a follow up examination after an average time of 3.7 years all patients could be reviewed clinically and radiologically. The clinical results have been very satisfying in all but one patient. Radiologically all patients showed early signs of gonarthrosis, but only in 4 of 12 patients more advanced signs of arthrosis were found. In their own opinion all patients were satisfied with the outcome of the operation, and two of them regarded the result as excellent. Besides the operative technique the indications practising autologous bone-cartilage-transplantation in large osteochondral defects of osteochondritis dissecans are described as well. Furthermore the advantages of autologous against homologous bone-cartilage-transplants are discussed.

Ultrasound examination for the early determination of dysplasia and congenital dislocation of neonatal hips

Hip sonography enables an accurate and clinically relevant evaluation of hip maturation during the first days of human life. Experience has shown that an integration of hip sonography into neonatal screening programs is useful and necessary because clinical and even roentgenographic examination does not always establish a confirmed diagnosis of dysplasia.

[The hip joint of children. Clinical diagnosis in the infant]

The relative importance of clinical findings is age-related. While instability is the key criterion in the neonatal phase, inhibition of abduction is of decisive importance as of the second month of life. However, the correct diagnosis can only be reached on the basis of a synopsis of all historical and clinical signs. Such signs are not sufficient to rule out disorders of hip maturation or to detect them beyond doubt, and above all early. Early diagnosis can only be improved by general sonographic screening of newborns. Clinical examination continues to be indispensable for differential diagnosis and for the introduction and performance of therapy tailored to the individual case.

Ultrasonography of achilles tendons in primary hypercholesterolemia. Comparison with computed tomography

Tendon xanthoma are a hallmark of familial hypercholesterolemia and are among its earliest clinical manifestations. Achilles tendon size, advanced to a generally accepted marker, is virtually specific for the disease and easily accessible for measurement. Hypercholesterolemic patients with coronary heart disease have been reported to have larger diameters of the Achilles tendons than patients without coronary problems. Furthermore, Achilles tendon xanthomas have been shown to regress with treatment of the lipid disorder. Mainly radiological procedures were applied in the past to evaluate the diameters of the Achilles tendon but their use is limited by radiation protection. We have used real-time ultrasonography to evaluate the Achilles tendons of 38 patients with primary hypercholesterolemia and 32 normocholesterolemic controls. The anterior posterior diameter in the patients was 13.4 +/- 5.9 mm (range 6-20 mm) and 5.7 +/- 0.7 mm (range 5-8 mm) in the control group. In 8 patients with newly diagnosed and previously untreated hypercholesterolemia the thickness correlated highly with their age. The Achilles tendons in about half of the patients (n = 21) showed a homogeneous thickening, whereas the others revealed an inhomogeneous thickening indicating the presence of circumscribed xanthoma. Upon comparison of the ultrasonographic procedure with an established method (computed tomography) in 18 patients and 8 normal volunteers a highly significant correlation (r = 0.96) proved the validity of the sonography. We show that real time ultrasonography is a valid procedure to assess Achilles tendon diameters in patients with primary hypercholesterolemia. It can be applied frequently and may be useful to follow xanthoma regression during lipid lowering treatment.

[Ultrasonic diagnosis of soft tissue tumors]

Ultrasonography is relatively simple to manage, has no known risks to be patient, and is quickly available, all of which makes it a valuable tool, among the imaging techniques, in the primary diagnosis and initial work-up of soft-tissue tumors. Ultrasonography can reveal the extent of a tumor. Preoperative examination of a tumor in any number of planes gives the clinician a spatial idea of its size. Additionally, the internal architecture and structure of the tumor can be assessed. Sonography can distinguish whether lesions are predominantly cystic, solid, or more complex. Calcium deposits or foreign bodies can be demonstrated in some cases. It is difficult to delineate the margins of a tumor by sonography. Expanding and displacing tumor growth or infiltration cannot be diagnosed with certainty. Perifocal edema can make tumors appear larger than they in fact are. Ab type-specific differences of soft tissue tumors are demonstrable by sonography. Tissue differentiation is not possible.

[Sonographic control of the clinical course of hip development disorders]

The ultrasonic examination is a valuable completation of the diagnostical possibilities of recognizing very early disturbed maturation of hips. In our clinic the employment of ultrasonic methods has proved extremely valuable in more than 1500 hips of newborns. The value of sonographic examinations of hips is represented by means of follow-up's.

[Follow-up results after lumbar renucleotomy]

This is a report on the results of reoperations of lumbar disc prolapses. Ninety-seven operations in ninety-one patients were performed for recurrence of a disc prolapse. The recurrence rate of the cases reviewed was 6.5 per cent. More than 80 per cent of the ninety-one patients who had answered a questionnaire were satisfied with the result of reoperation. About 66 per cent of the patients were able to pursue their former occupation, 20 per cent required vocational rehabilitation, in about 20 per cent of the cases disablement was acknowledged.

[Lumbar nucleotomy in children and adolescents]

Among 2987 patients operated on for lumbar disc protrusion between 1969 and 1980 twenty-six adolescents up to the age of twenty years have been found. This corresponds to 0.87 per cent. The average age at operation was 17.3 years, the youngest patient had twelve years. Twenty-one patients have been followed up for one to twelve years. The postoperative results as well as special details as to etiology and symptoms are discussed.

[Osteochondrosis dissecans of the patella (author's transl)]

This is a report on seven cases of osteochondritis dissecans patellae in which the diagnosis was made and operative treatment was performed. The clinical and roentgenological follow-up after an average of fourteen months shows that generally good results have been achieved by the fixation of the osteochondral fragments by cortical match stick grafts.

Experiments and calculations concerning a thermal enzyme probe

A simple device capable of measuring almost any reactant in an enzyme-catalyzed reaction is created when an enzyme is immobilized onto one thermal sensor of a differential thermometer. Experiments are described in which two thermistors, one bare and one coated with immobilized enzyme, are immersed in a well-stirred solution. The response of this device to increases in glucose-ATP concentration was observed using hexokinase (ATP:D-hexose 6-phosphotransferase, EC 2.7.1.1), and to increases in glucose concentration using glucose oxidase (beta-D-glucose:oxygen 1-oxidoreductase, EC 1.1.3.4). A simple model is presented whose predictions are in reasonable agreement with the experimental results.