The man who shot and killed Florida teenager Trayvon Martin has argued he acted in self defense. Evidence of his injuries may support his case.

George Zimmerman during a court appearance on April 20. Gary W. Green | AP

George Zimmerman had a broken nose, black eyes, cuts on the back of his head and a minor back injury the day after he shot and killed Florida teenager Trayvon Martin, according to medical records compiled by his doctor, ABC News reports.

Zimmerman, a 28-year-old neighborhood watch volunteer in Sanford, Fla., says he acted in self defense on Feb. 26 when he shot Martin, a 17-year-old African-American. Martin's family and supporters have argued that Zimmerman racially profiled the boy and followed him through the Sanford neighborhood before their tragic encounter. The case has rekindled a national discussion about race relations and racial profiling.

This latest report from ABC News means that network has in recent weeks gone from reporting that a police surveillance video of Zimmerman did not show any obvious evidence of injuries to saying that an enhanced version of that video did show some sort of injury on the back of his head to now reporting that according to the doctor:

"In addition to his physical injuries, Zimmerman complained of stress and 'occasional nausea when thinking about the violence.' But he was not diagnosed with a concussion. The doctor noted that it was 'imperative' that Zimmerman 'be seen with [sic] his psychologist for evaluation.' "

Zimmerman has pleaded not guilty to a charge of second-degree murder. He is currently out on bail.

Meanwhile, Orlando's WFTV-TV says that an autopsy report shows that along with the fatal gunshot wound to his chest, Martin had "broken skin on his knuckles."

Legal analyst Bill Sheaffer tells the station that Zimmerman's attorney may try to make the case that the injuries to Martin's knuckles support his client's case that he was punched by the teenager. But the injuries also "could be consistent with Trayvon either trying to get away or defend himself," Sheaffer told the station. [Copyright 2012 National Public Radio]