[Promoting venous return in plaster cast by AV impulse system. A preclinical study]. / Förderung des venösen Rückstroms im Liegegipsverband durch das AV-Impulssystem. Eine präklinische Untersuchung.

A new pneumatic compression pump--the AV-impulse system--causes increased return of venous blood from the lower limbs to the heart and increases total blood flow in the lower limbs by emptying the plantar venous plexus. Up to date there exist no experiences with using this system in plaster cast. We studied the maximum venous blood flow, the venous blood flow per minute and the venous diameters above the popliteal and femoral vein by duplexsonography in 12 lower limbs of 6 healthy persons before and after applying below-the-knee plaster casts. After applying the plaster cast we observed a slight increase in venous diameter (p = 0.02). By using the AV-impulse-system we observed a significant increase in maximum venous blood flow and venous blood flow per minute (p < 0.05). We demonstrated a significant increase of venous blood return in the deep veins of the lower limbs after applying a lower limb plaster cast by using the AV-impulse-system. These results indicate the possible benefit of using the AV-impulse-system as a physical method of thromboprophylaxis in orthopaedic and trauma patients with plaster cast immobilisation of the leg.

[Emergency care and treatment costs of polytrauma patients]. / Erstversorgungs- und Behandlungskosten polytraumatisierter Patienten.

Treatment costs of emergency therapy, surgery and intensive care were analysed in 20 randomly chosen, representative patients with severe multiple trauma (mean ISS 32 p). For an average stay of about 22.5 days on ICU, the total costs were DM 106924.36 (about 70,000 US $). DM 39,635.88 (= 37%) were the costs for physicians and nurses; DM 67,289.08 (= 63%) were needed for materials, X-rays, laboratory investigations, drugs and blood components. The whole treatment caused daily costs of DM 4752.22 or DM 3.30/min. The first emergency diagnostic procedures and emergency therapy take a mean time of 451.9 min from admission to the beginning of the ICU treatment and by itself already generates costs of about DM 12325.99. In Germany, a new way of compensation by a diagnosis-related group was introduced in 1996. These data suggest that treatment of severe multiple trauma is very expensive and trauma care could be economically harmful for smaller hospitals. We conclude that treatment of multiply injured patients (ISS > 16 p) should be compensated for by a special daily amount of about DM 5000 (about 3500 US $) for selected trauma centres.

[Quantitative determination of the effect of induced alternating currents on the integration of autologous spongiosa transplants]. / Quantitative Bestimmung des Einflusses von induziertem Wechselstrom auf die Integration autologer Spongiosatransplantate.

In a right-left experiment on the ulna of beagles, the authors investigate the influence of induced alternating current on the number of healed-in autologeous spongiosa grafts taken from the same side of the body. At first an atrophic pseudarthrosis is produced in both ulnae of twenty animals by bone resection and electrocoagulation over six months. Following to spongiosa transplantation and plate osteosynthesis, the ulnae are stimulated during eight weeks with a sinusoidal current of 38 cps and an electromagnetically induced alternating-current voltage of 600 mV on an average. The blindfold evaluation of the X-ray picture is performed by four experts and shows significantly better results in the stimulated side. By variance analysis of the results of electronic planimetry of serial layers in the region of transplantation represented by microradiography, it is demonstrated that the greater bone density of the stimulated grafts compared to the control grafts is statistically significant. It has to be considered that these results refer strictly to the electric data and treatment times applied by the authors. Particularly the results are not valid for the unique application of electromagnetic fields without alternating-current component.

[Indications and clinical results of electromagnetically-induced alternating current stimulation of poorly reacting pseudarthroses]. / Indikation und klinische Ergebnisse der elektromagnetisch induzierten Wechselstromstimulation reaktionsarmer Pseudarthrosen.

The authors present first results of clinical application of electromagnetically induced alternating-current voltage in 37 pseudarthroses showing poor reaction. The pseudarthroses had been persisting for two years on an average, the clinical pre-treatment time was seven months, the number of preceding operations was 2.76, eleven patients had been already operated by us one or several times without electric stimulation. Most of the pseudarthroses were contaminated; they were treated by sequestrotomy and immediate fixation with plate or marrow nail and autologous spongiosa graft. The alternating-current carrier was implanted in the bone with two electrodes each. When the wound was healed, the induction of alternating current was continued at home with a loan apparatus for three times 45 minutes to three times 2 hours daily. The electric treatment was performed during 6.7 months, the ossification was finished after 4.7 months, and the lower extremity could be fully loaded after five months. The recovery rate after one single operation is 89.2%. Repeated operations included, the total rate of recovery is 97.3%, no amputations. The review of literature shows that the method is favorable as to the stationary treatment time, the number of necessary surgical interventions, and the number of amputations.

[Electromagnetic fields and alternating current, do they accelerate bone healing? (author's transl)]. / Fördern niederfrequentes Magnetfeld und Wechselspannung die Knochenheilung?

The effects of combined treatment with electromagnetic fields and alternating current according to the method of Kraus is investigated in two groups at bone-nonunions of 21 beagle-dogs. Identical atrophic nonunions of both ulnae are stabilized with plates and treated electrically for eight weeks at one side only, the other side serves as control. The second group gets an additional cancellous bone graft. Qualitative and quantitative evaluation of X-rays and histology of undecalcified bone shows better bone healing in the group with cancellous bone graft on the treated side compared with the control. The first group shows no remarkable differences between both sides, except an increased periosteal bone formation around the active implants.

[Electromagnetic stimulation of infected experimental pseudarthrosis in a left-right study of beagles]. / Elektromagnetische Stimulation infizierter Defektpseudarthrosen im Rechts-Links-Versuch am Beagle.

Electromagnetic AC-stimulation according to the method of KRAUS was applied in 9 infected ununited ulnar fractures in the beagle. New cortical bone formation, bridging of the bone defect and the number of blood vessels in bone and soft tissue was assessed. Electromagnetic stimulation had no significant influence on bone healing or on the number of vessels.