Coxitis in newborns and infants.

From 1985 to 1996 (12 years) we saw 24 neonates and small infants with septic arthritis of the hip joint. A minority of these infants was simultaneously affected by osteomyelitis of the femoral neck or the acetabulum. Clinical signs are a painful leg, pseudoparalysis, uneasiness and refusal to drink. Quantitative measurements of C-reactive protein (CRP) are more reliable then leucocyte count and sedimentation rate. Ultrasound images yield early information about capsular swelling and septic effusion; in late cases US can visualize femoral neck necrosis. Emergency arthrotomy to relieve the joint from septic effusion, bacteriological specimens and capsular biopsy are mandatory. Intravenous application of a second-generation cephalosporin as antibiotic has proven effective. We have been using cefuroxim for the past 10 years, changed if necessary according to the antibiogram. Parenteral antibiotic treatment is continued for an average of 3 weeks, followed by oral treatment for another 3 weeks. CRP normalisation monitors the cure from the disease. Our 24 cases included 7 with group B streptococci 2 with Staphylococcus aureus, 2 with Staphylococcus epidermidis and 2 with Escherichia coli. In 8 cases no germs could be cultured; 6 of them had outside antibiotic treatment before being transferred. If treatment was initiated within 3 days, healing without residuals was the rule. In 18 cases with early and sufficient treatment no sequelae were observed. With delay of treatment for several days, moderate osteomyelitic changes of the neck and the acetabulum were observed. In a case with delay of surgical treatment for 5 weeks, complete destruction of the hip joint occurred, causing a poor final result.

Haematogenous multifocal osteomylitis.

The clinical features, diagnosis and treatment of haematogenous multifocal osteomyelitis, a rare illness, are described. Of clinical note are the pain, pseudoparalyses and restriction of movement. Staphylococcus aureus was the pathogen in both of the cases we described. Sonography is a useful diagnostic tool for the localization of subperiosteal abscesses; scintigraphy is a supplementary examination for cases where it is difficult to establish a diagnosis. MR-tomography is the most reliable method for examination of proximal infected foci (spondylitis, pelvis osteomyelitis). In our view, the earliest possible removal of all infected foci by means of operation and parenteral antibiotics mare the most important treatment.

Mapping of the thermal neutron distribution in the lead block assembly of the PS-211 experiment at CERN, using thermoluminescence and nuclear track detectors.

The main purpose of the TARC (Transmutation by Adiabatic Resonance Crossing) experiment (PS-211), was to demonstrate the possibility to destroy efficiently Long-Lived Fission Fragments (LLFF) in Accelerator Driven Systems (ADS). The experimental set-up which consisted of a lead block with dimensions 3.3 x 3.3 x 3 m3, was installed in a CERN Proton Synchrotron (PS) beam line. The proton beam at 2.5 GeV/c and 3.5 GeV/c, was incident in the centre of the lead block assembly producing neutrons via spallation reactions. In this study, neutron flux measurements are presented in the lead block assembly using thermoluminescence and nuclear track detectors. The results are in good agreement with Monte Carlo calculations as well as with the results of the other methods used in the framework of the TARC experiment.

[First material-adapted force hypothesis for calculating equivalent stress in human femurs]. / Erste werkstoffangepasste Anstrengungshypothese zur Berechnung der Vergleichsspannung an humanen Femura.

Strength hypotheses are assumptions, usually in the form of mathematical equations, which are applied in material science to convert multiaxial stress states in a material to a uniaxial stress state. Of particular interest regarding this conversion is the fact that the calculated uniaxial stress value in the material produces the same stress as the respective individual multiaxial stress. The "fictional" uniaxial stress determined in this way is also referred to as equivalent stress. Owing to the lack of experimental material data, many researchers and practitioners have in the past applied only the equivalent stress calculation based on the equations developed by von Mises under the assumption that the "material", bone, possesses isotropic properties. The present experimental work on selected human femora has been able for the first time, to quantify the anisotropy of these bones. At the same time a strength hypothesis has been formulated that can be used to convert multiaxial stress states for the material femoral bone to a uniaxial stress state (determination of equivalent stress).

[Forces acting on foot soles during stair climbing in healthy probands and in patients with coxarthrosis]. / Kräfte an den Fusssohlen beim Treppengang von gesunden und von Coxarthrose-erkrankten Menschen.

UNLABELLED: We investigated the contact forces acting on the sole of the foot of healthy persons and coxarthrosis patients climbing and descending stairs. The sole contact forces were determined using an experimental set-up comprising a stair construction provided with an integrated measuring step. RESULTS: In healthy subjects, the forces acting on the soles of the feet while climbing stairs were found to be 1.2 times their body weight. With regard to descending stairs, a distinction must be made between "hard" and "soft" walkers. In the case of "hard" walkers, the forces acting on the soles may be as much as 2.6 times body weight. These forces can be reduced by the wearing of shock-absorbing shoes. CONCLUSION: In coxarthrosis and prostheses-bearing patients, all movements are executed more slowly when climbing or descending stairs, so that only small dynamic forces arise. The greatest loads are about 1.2 times the patient's own weight. In these patients, an effective reduction by shockabsorbing footwear is not possible.

[The efficiency of various osteosynthesis techniques in fractures of the greater trochanter]. / Die Leistungsfähigkeit unterschiedlicher Osteosynthese-techniken bei Trochanter major-Frakturen.

Experimental investigations concerning the strength of different common used techniques of osteosyntheses of the greater trochanter were carried out on 22 cadaver femora. The maximal loading values were measured and analysed. Loading of the tilted femur corresponding to the bended-hip position decreased the tolerable loading values essentially.

[The magnitude of forces acting on the proximal femur in various weight alleviating gait forms with reduced ground reaction forces]. / Grösse der am proximalen Femur einwirkenden Kräfte bei unterschiedlichen entlastenden Gangarten mit reduzierten Bodenreaktionskräften.

To estimate the forces of the hip during partial or non-body-weight-bearing-gait a simple mechanical principle was used. For identification of the acting muscles of the hip during the swing period Electromyography was used. In the pure swing period without ground touch, being recommended as "de-loading" for the hip, forces resulted up to 85% of body-weight. In contrast to that, partial body-weight-bearing with limb-weight (approximately 12-15% body weight) resulted in the most efficient reduction of hip forces.

[Surgical technic in femur shaft fenestration within the scope of revision operations following hip joint total endoprostheses]. / Zur Operationstechnik bei der Femurschaftfensterung im Rahmen von Revisions-Operationen nach Hüftgelenk-Totalendoprothesen.

In revision arthroplasty the loss of stability secondary to fenestration of the proximal femur reduces the loading capacity of the limb and increases the risk of postoperative fractures. Trying to improve the fenestration technique we tested the usual fenestration procedure experimentally. Besides pure axial load we investigated the torsional forces of the proximal femur in the bended hip position. We recorded the deformation under increasing load and analysed the fracture pattern. The results shows an unwarantable loss of stability in lateral or complete ventral fenestration procedures. Ventral fenestration procedures with smooth edges and intact proximal bony ring having additional prosthesis stem support presented the best mechanical results. According to the tolerated load it is possible to give guide-lines for the postoperative treatment in the cemented and cementless arthroplasty of the hip joint.

[A treatment principle with questionable effectiveness in Perthes disease]. / Ein Behandlungsprinzip mit fragwürdiger Wirksamkeit bei Morbus Perthes.

The reduction of hip joint forces is a generally accepted part of the conservative treatment of Perthes disease. To reach this effect with help of splints (e.g. Thomassplint and the following models) does not seem to be efficient enough even from a clinical point of view. Theoretical considerations of former investigations of other authors point out the insufficient effect of these splints regarding the hip joint force reduction during the weight bearing phase in walking. The effect of these splints during the non-weight bearing phase in walking with regard to the hip joint forces has not been investigated so far. Therefore this paper is dealing with the forces onto the hip joint during the swinging phase of the leg with a splint, shown in a simplified, mechanical model. The results reveal significantly higher hip joint forces if the splint is used compared to the physiological forces during the swinging phase which in a static situation rise up to twice the body weight. These joint loadings are important because they occur during hip flexion and therefore cause pressure on the ventro-cranial part of the head of the femur, a region which unfortunately is often involved in Perthes' disease and therefore especially vulnerable to these forces. From a biomechanical point of view the principle of reducing the hip joint forces with splints has to be abandoned.

[Coxitis in the newborn infant and infant. Diagnosis and therapy]. / Die Koxitis beim Neugeborenen und Säugling. Diagnose und Therapie.

From 198 o 1996 (12 years) we saw 24 neonates and small infants with septic arthritis of the hip joint. A minority of these infants was simultaneously affected by osteomyelitis of the femoral neck or the acetabulum. Clinical signs are a painful leg, pseudoparalysis, uneasiness and refusal to drink. Quantitative measurements of C-reactive protein (CRP) are more reliable then leucocyte count and sedimentation rate. Ultrasound images yield early information about capsular swelling and septic effusion; in late cases US can visualize femoral neck necrosis. Emergency arthrotomy to relieve the joint from septic effusion, bacteriological specimens and capsular biopsy are mandatory. Intravenous application of a second-generation cephalosporin as antibiotic has proven effective. We have been using cefuroxim for the past 10 years, changed if necessary according to the antibiogram. Parenteral antibiotic treatment is continued for an average of 3 weeks, followed by oral treatment for another 3 weeks. CRP normalisation monitors the cure from the disease. Our 24 cases included 7 with group B streptococci 2 with Staphylococcus aureus, 2 with Staphylococcus epidermidis and 2 with Escherichia coli. In 8 cases no germs could be cultured; 6 of them had outside antibiotic treatment before being transferred. If treatment was initiated within 3 days, healing without residuals was the rule. In 18 cases with early and sufficient treatment no sequelae were observed. With delay of treatment for several days, moderate osteomyelitic changes of the neck and the acetabulum were observed. In a case with delay of surgical treatment for 5 weeks, complete destruction of the hip joint occurred, causing a poor final result.

[Hematogenous multifocal osteomyelitis]. / Hämatogene multifokale Osteomyelitis.

The clinical features, diagnosis and treatment of haematogenous multifocal osteomyelitis, a rare illness, are described. Of clinical note are the pain, pseudoparalyses and restriction of movement. Staphylococcus aureus was the pathogen in both of the cases we described. Sonography is a useful diagnostic tool for the localization of subperiosteal abscesses; scintigraphy is a supplementary examination for cases where it is difficult to establish a diagnosis. MR-tomography is the most reliable method for examination of proximal infected foci (spondylitis, pelvis osteomyelitis). In our view, the earliest possible removal of all infected foci by means of operation and parenteral antibiotics mare the most important treatment.

[Prolonged transitory paralysis after pneumatic tourniquet use on the upper arm]. / Prolongierte passagere Paralyse nach pneumatischer Blutsperrenanwendung am Oberarm.

A case of paralysis in a youth lasting 7.5 months caused by application of a tourniquet is described. The paralysis was induced by the brief application of excessive cuff pressure. The function of the arm nerves returned spontaneously.

[Experimentally established material data of human femurs and analysis of direction-dependent stress tolerance]. / Experimentell ermittelte Werkstoffdaten von humanen Oberschenkelknochen und Analyse der richtungsabhängigen Beanspruchbarkeit.

All the calculations given in the literature concerning the material data for human femora are based on the very simplistic assumption that the bone is isotropic, i.e. that it has the same mechanical behaviour in every direction. This assumptions has been employed by all authors because no detailed data on bone as a material, especially in connection with the human femur. The results of the present experiments show, however, that the femur exhibits variations in material data which are markedly direction dependent, so that support can no longer be given to the simplistic assumption of isotropic behaviour.

[The tensile strength of various osteosyntheses of the unstable major trochanter. An experimental study]. / Die Zugfestigkeit unterschiedlicher Osteosynthesen des instabilen Trochanter major. Eine experimentelle Studie.

Eight of the prevalent techniques for performing osteosynthesis of the greater trochanter were compared to determine the stability of each. In an experimental setup, the reaction to deformation in the osteotomy cleft as a result of increasing tension stress was determined and analyzed in the femora of 22 corpses. The strain tolerance was not only dependent on the particular form of osteosynthesis but also on the technical details. Our study on the reaction to deformation showed that even low levels of tension stress caused significant dislocation in the osteyomy cleft despite an intact osteosynthesis. The results permit conclusions to be drawn that will contribute to the improvement of surgical technical details as well as postoperative treatment.

[Studies on the stability of pertrochanteric fractures following the application of various osteosynthesis techniques with special reference to torsional forces at the proximal femur]. / Untersuchungen zum Festigkeitsverhalten pertrochanterer Frakturen nach Anwendung verschiedener Osteosynthesetechniken unter besonderer Berücksichtigung der Torsionsbelastung am proximalen Femur.

Fourteen different commonly used osteosyntheses for unstable pertrochanteric fractures with medial bone defect were systematically analysed concerning their stability. For this purpose the deformation and the maximum stability of 36 surgically stabilized fractured femora from donor corpses were tested. For the experimental investigations the hip force FM was not only induced on the femora in orthograde direction but also in an inclination of 45 degrees of anteflexion of the femur as it appears during walking up stairs. As a result, all tested osteosyntheses had significantly lower maximum stability and greater deformation if the hip force was induced on the anteflexed femur in contrast to orthograde loading. From our analysis clinically important conclusions can be drawn concerning the operation techniques and the post-operative after treatment concepts.

[Concomitant vascular complications in supracondylar humerus fractures in children]. / Begleitende Gefässkomplikationen bei suprakondylären Humerusfrakturen des Kindes.

From January 1st 1990 to December 31st 1997, 614 children were treated for supracondylar humerus fracture at the Department of Orthopedic Surgery in the Olga Hospital, Stuttgart. Ten of these children had concomitant vascular complications. The concept of treatment we had chosen was analysed retrospectively. The median patient age of the seven girls and three boys with vascular complications was six years. The vascular injuries were diagnosed after admission to the hospital by palpation of the wrist pulse, clinical appraisal of the vascularity and by registration of the Doppler signal via the arteries of the wrist. The emergency operations carried out initially comprised fragment reposition and fixation with crossed K wires via an access route on the extensor side in all ten children. The subsequent appraisal of the blood flow revealed a pulse restoration (transient vascular occlusion due to dislocation) in two out of the ten children. In eight out of the ten children, the pulse did not return, which is why the vessel had to be explored under emergency conditions. Intraoperatively, we saw a vascular spasm with functional vascular occlusion in one of these eight children. Mechanical vascular occlusion were diagnosed in five of these eight children. In adventitial strangulation (two of these five children), the pulse transmission to the hand occurred immediately after severance of the strangulation connective tissue. In intimal damage (three of these five children), the vascular segment concerned was resected and reconstructed, mostly in the form of an end-to-end-anastomosis with venous patch grafting. We observed a combined vascular occlusion (mechanical-functional occlusion) in two out of these eight children. In the follow-up investigation, the wrist pulses could be palpated in nine children. Nine children had a physiological signal in color duplex sonography, and one child had a pathological monophasic signal over the brachial artery, radial artery as well as the ulnar artery. Late ischemic damage (cold intolerance, claudicatio, Volkmann's contracture) were not detected in any of the children. Appraisal of elbow joint mobility revealed a median extension deficit of 0 degrees (range 0-10 degrees ), a median flexion deficit of 0 degrees (range 0-15 degrees ) and a normal pronation and supination equal on each side. The load-carrying joint axis was normal in a comparison of the sides in all children.