A former Hooters waitress has sued the restaurant chain in federal court, alleging she was pushed out of her job after brain surgery left her with buzz cut hair and a healing scar that made it too painful to wear a wig.

Sandra Lupo, 27, had worked as a waitress at a St. Peters, Mo., Hooters since April 2005 but took a leave from her job for a few weeks last summer to have a cranial mass removed.

Lupo had the support of her manager, who visited her in the hospital and suggested when she was ready to return to work that she wear a "chemo cap" or jewelry items "to distract from her lack of hair and the visibility of her cranial scar," court documents said.

On July 16, 2012, doctors gave Lupo clearance to go back to work at Hooters, where she worked to put herself through nursing school.

RELATED: Melissa Nelson: Dental Assistant Fired For Being 'Irresistible' Is 'Devastated'

Shortly before she returned to work, Lupo and her immediate manager met with the Hooters regional manager who said Lupo would be required to wear a wig while at work, according to court documents.

Lupo told him "she did not have a wig and that she could not afford a wig, as they range in cost between several hundred and several thousands of dollars," according to the lawsuit, adding that the regional manager did not offer to pay for the wig.

After her manager approached her again regarding a wig, Lupo said she borrowed one and tried to wear it at work. But it "caused extreme stress to her body because of the surgery and the healing wound," according to court records.

Lupo said her manager then reduced her hours to the point where she was making so little income that she was forced to quit, which made her ineligible for unemployment benefits.

"[Lupo's] physical injury was an actual disability from her surgery which limited the major life activity of working when such work required a wig to be worn," court documents said.

In a complaint filed with the Missouri Commission on Human Rights, Lupo said she never believed her customers were ever "offended" by her appearance at the chain, which is known for its hot wings and servers clad in tight white tank tops and orange hot pants.

"My customers were not offended, and were in fact curious about the obvious scar from my surgery," she wrote in the complaint.

The lawsuit was moved from St. Charles County Circuit Court to U.S. District Court in St. Louis last week at the request of Georgia-based Hooters.

"Hooters of America believes the lawsuit is without foundation, denies the accusations and has filed a motion that the lawsuit be dismissed," a spokesman wrote in an email to ABCNews.com.

Lupo, whose attorney said Lupo now works as a trauma nurse, was not immediately available for comment.

The Americans With Disabilities Act prohibits employers from discriminating against qualified individuals who have a disability. This includes having a physical or mental impairment, a history of having an impairment or the perception of having one.

Marcia McCormick, an associate professor of law at St. Louis University, said Lupo's surgery to remove a brain mass qualifies as a disability, but that Hooters could argue that her appearance was a bona fide qualification for her job.

"In the disability context, if Hooters is to say she's not as attractive now without this wig, if they're selling her attractiveness that might be a real function of her job and mean she isn't qualified by the Americans With Disabilities Act," McCormick said.

"Most companies can't say something like this, but Hooters sells this experience," she said.