Internal fixation of fractures of the proximal humerus with the MultiLoc nail.

OBJECTIVE: Anatomical reduction of two- to four-part fractures of the proximal humerus using indirect reduction techniques. Intramedullary fixation with a short humerus nail. Restoration of a stable bone-implant construct that enables early functional after-treatment. INDICATIONS: Displaced and unstable two- to four-part fractures of the proximal humerus. Fractures of the proximal humerus extending in the humeral diaphysis (use a long nail). Ipsilateral combined lesions of the proximal humerus and the humeral diaphysis (use a long nail). CONTRAINDICATIONS: Poor physical and/or mental status. Critical soft tissue conditions in the area near the surgical site. Local soft tissue infection. Pre-existing severe osteoarthritis of the shoulder joint; severe shoulder stiffness. Head-split fractures of the humerus head that cannot be reduced. SURGICAL TECHNIQUE: Exposure of the fracture using an anterior acromial approach and determination of the correct nail entrance point. Anatomic fracture reduction using indirect reduction techniques. Stable fixation using an intramedullary MultiLoc® nail. Determination of the proximal locking configuration depending on the fracture morphology. Distal locking with angle-stable option. POST-OPERATIVE TREATMENT: Post-operative radiographs for documentation of the surgical result and implant position. Use of an arm sling for 7-10 days. Active and passive exercises of the shoulder joint starting on day 1. Shoulder abduction limited to 60° for 2 weeks. Subsequent abduction to 90° until the 4th week. Subsequent active mobilisation without restrictions. Weight bearing and sporting activities after 3 months. Radiological evaluation after 2, 6 and 12 weeks. RESULTS: During a 6-month period, 160 patients were documented in a prospective clinical multicentre study. According to the AO classification, there were 36% A-type fractures, 41% B- and 23% C-type injuries. A 6-month follow-up was available for 17 patients. The mean age of these patients was 67 years. One patient had an A-type fracture. There were ten B- and six C-type fractures. At the time of follow-up, the mean Constant score was 66 points. Radiographically, all fractures had healed. Intra-articular screw penetration and loss of reduction were both observed once.

Calcium prevents loss of glutathione and reduces oxidative stress upon reperfusion in the perfused liver.

BACKGROUND: Addition of 1.5 mM Ca2+ to the preservation solution (UW) during static cold rat liver preservation have been shown to improve liver function upon reperfusion. Effects of adding calcium to the perfusate during liver machine perfusion are yet not described. METHODS: A recently developed model for rat liver machine perfusion (hypothermic oscillating oxygenated liver perfusion) was used to perfuse rat livers with calcium free modified UW solution (Group 1) or with modified UW + 2 mM CaCl2 (Group 2) for a period of 10 h (4 degrees C). In both experimental groups an acellular reperfusion at 37 degrees C with Ringer solution and 50 microM ferricytochrome c over a period of 90 min was performed. Liver and perfusate samples were taken before and after reperfusion to assess the cellular energy charge, metabolites, parameters of oxidative stress, cellular calcium, bile flow, enzyme release and TNF alpha. RESULTS: Hypothermic perfusion with oxygenated calcium free modified UW solution resulted in depletion of cellular calcium and glutathione. Upon reperfusion bile function was inhibited in spite of a sufficiently reloaded energy charge and low LDH release. In contrast machine perfusion with modified UW solution +2 mM Ca2+ prevented the loss of both, cellular calcium and glutathione during the preservation period and led to sufficient bile flow and less release of superoxide anions upon reperfusion. CONCLUSIONS: The loss of cellular calcium and glutathione during oxygenated machine liver perfusion appeared to be reducible by adding 2 mM Ca2+. Furthermore, upon reperfusion, livers with preserved cellular calcium demonstrated significantly lower oxidative stress and an improved liver function.

Reduced oxidative stress during acellular reperfusion of the rat liver after hypothermic oscillating perfusion.

BACKGROUND: ATP resynthesis during reperfusion after liver preservation has been shown to be well correlated with the function of transplanted grafts. Nevertheless, the advantages of a cellular energy charge loading during the preservation period are yet not fully understood. This study evaluates the effects of different nucleotide levels at the end of preservation on metabolic changes and oxidative stress during reperfusion. METHODS: Two experimental groups were chosen reflecting different energy charge states after preservation: static cold storage for 10 hr and hypothermic oxygenated oscillating perfusion for 10 hr. In both experimental groups, normothermic ex vivo acellular reperfusion over 40 min was performed. A third group consisted of nonpreserved livers similarly reperfused for 40 min. Superoxide formation was detected by the superoxide dismutase inhibitable reduction of ferricytochrome c added to the normothermic perfusate. RESULTS: Superoxide formation and lipid peroxidation malondialdehyde were significantly lower during reperfusion after the energy charge loading before reperfusion by the hypothermic oscillating perfusion technique. However, oxygen radical formation, liver cell injury (lactate dehydrogenase [LDH] release), and TNFalpha release were significantly higher in energy charge-depleted groups (nonpreserved and cold stored livers). CONCLUSIONS: Hypothermic oscillating oxygenated perfusion led to the elevated energy charge during preservation and led to reduced oxygen radical formation as well as less lipid peroxidation during reperfusion, in contrast to cold stored livers and nonpreserved livers. This suggests a correlation between the energy charge before reperfusion and oxygen radical formation as well as liver injury at reperfusion.

Hypothermic oscillating liver perfusion stimulates ATP synthesis prior to transplantation.

BACKGROUND: ATP and glycogen depletion often have been demonstrated during cold storage of the liver prior to transplantation. Suppression of events that lead to metabolic depression and to lipid peroxidation could contribute to improvement of liver preservation. A new method of liver preservation for transplantation is therefore suggested, an oscillating oxygenated hypothermic liver perfusion. METHODS: Biochemical analysis of liver tissue samples and perfusate after 10 h of perfusion by the presented oscillating perfusion model were compared with results after continuous liver perfusion for 10 h as well as with data derived from cold-stored livers over a period of 10 h. Particular reference was made to nucleotide metabolites, glycogen content, lipid peroxidation, glutathione content, glycolytic metabolites, and enzyme release before and after preservation. RESULTS: Glycogen depletion occurred to the same degree in hypothermic storage and machine perfusion (oscillating as well as continuous perfusion), but the energy charge was significantly increased after oxygenated perfusion, whereas cold storage resulted in a significant energy charge depletion. In addition, perfusion by an oscillating technique yielded superior energy charge loading compared to the continuous perfusion technique and diminished the other hand lipid peroxidation. CONCLUSIONS: Hypothermic oscillating oxygenated perfusion could be important for the improvement of the quality of energy-depleted organs prior to transplantation.