Medical Device Dailys

This month Siemens Healthcare (Erlangen, Germany) is rolling out in Germany, Austria and Switzerland the Cappa C-Nav system for navigation and guidance during minimally-invasive surgical procedures.

An optics-based navigation system suited to primarily spinal surgery, as well as some trauma surgery applications, the Cappa C-Nav makes its world début at the Congress of the European Federation of National Associations of Orthopaedics and Traumatology being held this week in Vienna, Austria.

Perioperative X-ray images are used to create a 3-D map of the target surgery site and then instruments and markers on the patient's body are calibrated with an infrared optic system.

Intra-operative navigation is provided by a stero infrared camera that continuously track the movement of instruments relative to the fixed positions on the patient and referencing the 3-D X-ray image.

This capability enhances accuracy, for example virtually testing the length of the pedicle screws and verifying their placement, which is credited with reducing re-interventions for repair or rescue procedures.

Cappa C-Nav can be retrofitted for hospitals with Siemens' mobile C-arm Arcadis Orbic 3D.

CAS innovations (also Erlangen) develops computer-assisted surgical navigation systems for Siemens using electromagnetics and optical tracking.

CAS and Siemens entered into a collaborative agreement at the end of 2005 and Siemens subsequently acquired the company in February 2008.

Faulty genes could reveal bone disease risk

The discovery of faulty genes by University of Edinburgh (Edinburgh, Scotland) researchers could help people with Paget's disease, a painful bone condition.

Omar Albagha, MD, reported finding three genes associated with the disease which, if detected early enough in people, could hasten diagnosis and treatment.

Paget's disease affects around 3% of the population over 55 in the UK. The carefully regulated system of renewing bone is disrupted. New bone cells (osteoblasts) increase dramatically, are overactive and enlarged causing weak, misshapen bones leading to pain deformity, osteoarthritis, fractures and even deafness.

Genetic factors are important but until now, only one gene is known to be linked to one-third of the people with Paget's disease. The research team in the rheumatology section at the university wanted to find other gene abnormalities that might predispose people to the disease.

Speaking at the European Symposium on Calcified Tissue in Vienna, Albagha said, "This discovery is important so that we can better understand the development of Paget's disease and identify those at risk."

There were 750 patients with Paget's disease in the study. They did not have the known faulty gene, but 104 of them had a family history of the disease. About 1,000 healthy people were in the control group.

In the analysis of more than 300,000 gene variations covering all known human genes, three genes were found to be associated with Paget's disease. Further research is now under way to determine how these faults cause the disease.

"Now we have identified the faulty genes, we will be able to develop ways to screen people ideally in their 30s with a family history of the disease. If necessary, we give them treatment early before the damage is done," Albagha said.

Change in measurement of HbA1c

Beginning June 1, HbA1c (long-term blood glucose levels) in all people with diabetes will be measured in millimoles per mol as well as by percentage, the UK Department of Health said.

The UK is responding to the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) call for all countries to adopt the same measurement to make it easier to compare HbA1c results among laboratories throughout the UK and worldwide.

Both the old and the new measurements will be given for the first two years of the change, until May 31, 2011, when people with diabetes will receive their HbA1c measurement only in millimoles per mol.

Dr. Rowan Hillson, national clinical director for diabetes, said, "It is really important that people with diabetes keep their blood glucose levels under good control. Controlling the glucose in a way that is safe and appropriate for each person reduces the risk of diabetic tissue damage. People with diabetes need HbA1c blood tests to check their glucose is under good control. This . . . change in the way that HbA1c is reported is being introduced in a way that allows plenty of time for us all to get used to it."

Simon O'Neill, director of care and policy at Diabetes UK, said, "Diabetes UK welcomes this change to the way HbA1c results are reported and we believe that this will have the additional benefit of making comparing results from international laboratories and research trials easier, as the new system will be adopted worldwide."

He added, "For a period of two years, people with diabetes will get their results in both percentage and millimoles per mol, which will help them get used to the new system. In addition, Diabetes UK has designed a convenient online HbA1c converter tool for people with diabetes to help them through the transition."