[Growth and differentiation factor 5 (GDF-5) composite improves the healing of necrosis of the femoral head in a sheep model. Analysis of an animal model]. / Das Wachstumsfaktorkomposit aus GDF-5 und mineralisiertem Kollagen verbessert die Ausheilung einer Hüftkopfnekrose. Eine Untersuchung im Tiermodell.

MATERIALS AND METHODS: After creation of necrosis in 23 sheep, the composites were implanted in half of the animals. The animals were sacrificed 6 and 12 weeks after implantation and the femora were harvested. The specimens were investigated by microradiography, computed tomography, and histologically. RESULTS: The GDF-5 composites were effective in the necrosis model. Osseous regeneration of the necrosis and the drill track were accelerated and enhanced by the composites. In treated animals the necrosis was nearly healed and the drill track was filled with bone after 12 weeks. In the control group the track was partially filled with fibrous tissue and necrotic lesions were still present. Specific side effects of the growth factor or the matrix were not documented. This was documented by histological scoring and CT investigation. DISCUSSION: The application of an absorbable GDF-5 composite in combination with a core decompression procedure may enhance the healing of devitalized bone defects and is a promising approach for further studies.

Restoration of liver function and portosystemic pressure gradient after TIPSS and late TIPSS occlusion.

TIPSS (transjugular intrahepatic portosystemic shunt) may be indicated to control bleeding from esophageal and gastric varicose veins, to reduce ascites, and to treat patients with Budd-Chiari syndrome and veno-occlusive disease. Numerous measures to improve the safety and methodology of the procedure have helped to increase the technical and clinical success. Follow-up of TIPSS patients has revealed shunt stenosis to occur more often in patients with preserved liver function (Child A, Child B). In addition, the extent of liver cirrhosis is the main factor that determines prognosis in the long term. Little is known about the effects of TIPSS with respect to portosystemic hemodynamics. This report deals with a cirrhotic patient who stopped drinking 7 months prior to admission. He received TIPSS to control ascites and recurrent esophageal bleeding. Two years later remarkable hypertrophy of the left liver lobe and shunt occlusion was observed. The portosystemic pressure gradient dropped from 24 mmHg before TIPSS to 11 mmHg and remained stable after shunt occlusion. The Child's B cirrhosis prior to TIPSS turned into Child's A cirrhosis and remained stable during the follow-up period of 32 months. This indicates that liver function of TIPSS patients may recover due to hypertrophy of the remaining non-cirrhotic liver tissue. In addition the hepatic hemodynamics may return to normal. In conclusion, TIPSS cannot cure cirrhosis but its progress may be halted if the cause can be removed. This may result in a normal portosystemic gradient, leading consequently to shunt occlusion.