A judge has dismissed a lawsuit brought against Harvard Medical School Professor Douglas P. Kiel for a study he led on padded underwear meant to protect the elderly from hip fractures.

The Tuesday ruling in Norfolk Superior Court brought an end to the lawsuit in which HipSaver, a hip protector manufacturer based in Canton, Mass., sued Kiel for commercial disparagement.

The study, which came under fire from the Department of Health and Human Services for not fully disclosing risks of injury to its participants, concluded that hip protectors are not effective in preventing hip fractures. HipSaver alleged that the claim was damaging to its product.

However, in Tuesday's ruling, Associate Justice Barbara A. Dortch-Okara found that because HipSaver would not be presenting evidence that either directly contests the study's conclusion or alleges that Kiel was acting maliciously, commercial disparagement could not be proven.

HipSaver filed the suit on Feb. 15, 2008.

Kiel still faces scrutiny from the HHS Division of Compliance Oversight. In a 13-page letter sent to research administrators at institutions affiliated with the study, federal health regulators said that the researchers did not keep participants informed of risks they discovered as the study progressed.

The study design, which involved fitting patients with underwear that had padding only on one side, resulted in participants falling more frequently to the side with padding compared to the side without padding. When researchers noticed this trend, they failed to disclose it to participants, HHS said.

HipSaver said it requested this investigation, resulting in HHS requiring researchers to contact participants to inform them of the risk of falling on one side.

—Staff writer Naveen N. Srivatsa can be reached at srivatsa@fas.harvard.edu.