A new crash test simulating a smaller frontal collision showed significant safety gaps among certain midsize luxury cars, according to the Insurance Institute for Highway Safety.

The IIHS, a nonprofit organization of insurance companies, found that only two of 11 luxury cars scored a "good" rating on the new test, an "offset" crash that puts more stress on a car's front corners and wheel assemblies. The new test focuses the impact on just 25 percent of the car's front end, compared with 40 percent in the older test. This kind of impact, the IIHS says, is a major cause of fatalities and one that normally goes unaddressed.

The new test, like the IIHS's roof-strength ratings in 2009 and its efforts to evaluate active safety systems, is part of a continuous attempt to make it tougher for automakers to earn spots on the vaunted Top Safety Pick list. 

"Nearly every new car performs well in other frontal crash tests conducted by the institute and the federal government, but we still see more than 10,000 deaths in frontal crashes each year," IIHS President Adrian Lund said in a press release.

Only the Volvo S60 and Acura TL scored "good." Both cars had sufficient body-frame strength to prevent the wheel assemblies from intruding into the cabin, the IIHS said. The Infiniti G37 was rated "marginal," while eight other 2012 models -- including the BMW 3 Series and Mercedes-Benz C-Class -- rated "poor." Those vehicles were likely to cause a "high risk of injury to the legs and feet," the IIHS said.

In some cases, as with the Lincoln MKZ, the crash-test dummy's head missed the front airbag because of intrusions. In testing on the Volkswagen CC, the driver's door flew off. While most vehicle safety cages and crush zones are effective within the "middle 50 percent" of the car's front end, few cars have enough strength on their edges to prevent serious injuries, the IIHS said.

The group's next step is to crash less expensive midsize cars such as the Honda Accord. However, in an interview with the Los Angeles Times, Consumer Reports said it doesn't expect there to be significant improvements in this small-offset crash test for five or even 10 years.

[Source: IIHS]