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M Genge

Publications and source records attributed to M Genge.

4 recordsLinked to original sources
PubMed2001

Loads acting in an intramedullary nail during fracture healing in the human femur.

The form and function of the musculo-skeletal system is closely related to the forces acting in its components. Significant forces are present in the long bones, but their magnitudes have so far only been estimated from mathematical models. Fracture fixation by means of metal implants provides an opportunity to measure the implant-born forces and to estimate the long bone forces before healing occurs. The load changes during fracture healing may provide additional information. Therefore, a telemetrized, interlocking femoral nail for wireless transmission of forces and moments acting across the fracture site was developed. The design was based on the geometry and material of a 16 mm AO nail with a circular, closed cross-section allowing full protection of the electronic circuits from the body fluids. After careful testing, it was implanted in a 33-year-old patient who had sustained a multifragmentary fracture of the left femur. Measurements at a rate of approx. 0.4 Hz were performed in different patient postures between the 2nd and 26th postoperative week. Significant axial forces and bending moments were measured during several activities such as sitting, unsupported leg elevation and partial weight bearing in a standing position. Forces orthogonal to the nail axis remained small. The reductions of the implant loads due to fracture consolidation were in the order of 50%. Dynamization of the nail did not change the forces. Even though the telemetry system did not allow for dynamic measurements and the results presented here provide data from one subject only, the new information will be useful with respect to implant design, biomechanics of fracture fixation and evaluation of healing progression.

Adult↗
PubMed1997

A new biological glue for cartilage-cartilage interfaces: tissue transglutaminase.

In this study, we used an in vitro model to test the capacity of tissue transglutaminase to increase the adhesive strength at a cartilage-cartilage interface. Full-thickness cartilage-bone cylinders were prepared from fresh adult bovine shoulder joints, and the superficial half of the hyaline cartilage was then removed to provide a plane surface. Tissue transglutaminase was applied to the freshly cut surface of one cylinder, and a calcium-chloride solution (to act as an activating agent) was applied to that of the other. The cartilage surfaces were immediately apposed, one on top of the other, and an eighty-gram weight was applied to the upper cylinder for ten minutes at 37 degrees Celsius under defined humidity conditions. A measured force was then applied transversely to the upper cylinder until it was displaced from the lower one (which was clamped in a holding device), and the force recorded at this point was taken as a measure of the adhesive strength achieved at the cartilage-cartilage interface. The adhesive strength increased linearly with an increasing concentration of tissue transglutaminase (0.25 to 2.75 milligrams per milliliter) and was enhanced by increasing the duration of incubation, but it was not influenced by the level of humidity. The adhesive strength was improved by as much as 40 per cent when the cartilage surfaces had been pretreated with chondroitinase AC or hyaluronidase to remove glycosaminoglycan chains of proteoglycans, which are largely responsible for the intrinsic anti-adhesive properties of cartilage.

Adhesiveness↗
PubMed1989

Contrast material-induced renal failure in patients with diabetes mellitus, renal insufficiency, or both. A prospective controlled study.

To determine the risk of nephrotoxicity induced by the infusion of radiographic contrast material, we undertook a prospective study of consecutive patients undergoing radiographic procedures with intravascular contrast material. There were three study groups: patients with diabetes mellitus and normal renal function (n = 85), patients with preexisting renal insufficiency (serum creatinine level, greater than or equal to 150 mumol per liter) without diabetes (n = 101), and patients with both diabetes and renal insufficiency (n = 34). The control group consisted of patients undergoing CT scanning or abdominal imaging procedures without the infusion of contrast material who had diabetes mellitus (n = 59), preexisting renal insufficiency (n = 145), or both (n = 64). Clinically important acute renal failure (defined as an increase of greater than 50 percent in the serum creatinine level) attributable to the contrast material did not occur in nondiabetic patients with preexisting renal insufficiency or in diabetics with normal renal function. The incidence of clinically important contrast-induced renal failure among the diabetic patients with preexisting renal insufficiency was 8.8 percent (95 percent confidence interval, 1.9 to 23.7 percent), as compared with 1.6 percent for the controls. The incidence of acute renal insufficiency, more broadly defined as an increase of greater than 25 percent in the serum creatinine level after the infusion of contrast material, was 11.8 percent among all patients with preexisting renal insufficiency. After the exclusion of patients whose acute renal insufficiency could be attributed to other causes, the incidence was 7.0 percent (95 percent confidence interval, 3.2 to 12.8 percent), as compared with 1.5 percent in the control group. The risk of acute renal insufficiency attributable to the contrast material was therefore 5.5 percent, and the relative risk associated with the infusion of contrast material was 4.7. These rates were similar whether the osmolarity of the contrast material was high or low. We conclude that there is little risk of clinically important nephrotoxicity attributable to contrast material for patients with diabetes and normal renal function or for nondiabetic patients with preexisting renal insufficiency. The risk for those with both diabetes and preexisting renal insufficiency is about 9 percent, which is lower than previously reported.

Clinical Trials as Topic↗