WEST PALM BEACH, Fla. (AP) _ William Kennedy Smith's attorneys were ready today to begin presenting their defense, after the judge turned down prosecution efforts to present one last state witness, a rape expert.

Circuit Judge Mary Lupo said presentation of the testimony of Dr. Dean Kilpatrick would have a ''devastating effect'' on the trial schedule, noting she had promised jurors the case would wind up before Christmas.

The judge, however, left open the possibility that Kilpatrick could be presented as a rebuttal witness.

Smith's attorneys had argued that prosecutors violated state rules by failing to notify them of their planned witness until Nov. 27, only five days before the beginning of testimony, meaning they didn't have reasonable time to question him and investigate his credentials.

Defense attorneys told Ms. Lupo they could start their case this afternoon after the state rested.

On Friday, jurors heard Smith's uncle, Sen. Edward M. Kennedy, testify that he wished he'd gone for a walk instead of inviting his son and nephew on the fateful visit March 30 visit to a bar led to rape charges.

At one point, Smith wept as his uncle talked about his father, Stephen, who died in August 1990. Kennedy said he asked his son and Smith to join him for some late-night drinks so he could unwind after an emotional family discussion about the death.

''I wish I'd gone for a long walk on the beach instead, but we went to Au Bar,'' Kennedy said.

Smith's attorneys say the woman consented to sex with Smith and later became vengeful.

An orthopedic surgeon who examined Smith's accuser a week after the incident testified today, the sixth day of testimony, about his findings she had pain or tenderness in her shoulders, rib cage, hip and pubic bone. Dr. Barry Lotman testified that the woman said the pain had worsened during the days after the incident as shock set in.

''It hurt her to take a deep breath,'' said Lotman.

She also had ''a tremor in her right arm ... almost like a palsy,'' Lotman said. He added that the woman told him she had been raped and asked him about the possibility she was infected with the AIDS virus because of that. The woman later tested negative for AIDS.

However, defense attorney Mark Seiden said the woman's pain complaints were the same as earlier complaints she had made stemming from a broken neck she suffered in a car accident as a teen-ager. Lotman had treated the woman for her continuing othopedic problems even before the alleged rape.

Lotman testified her injuries limited her movements, but he answered ''yes'' to a series of questions about how she might have resisted an attacker.

''Could she kick?'' Seiden asked. ''Could she bite? Could she scratch? Could she scrape? Could she punch? Could she use her knee in someone's groin? Could she scream? She could run?''

Seiden also asked whether some patients fake pain for the purpose of lawsuits. ''It is possible to fake pain,'' Lotman replied.

Palm Beach police Sgt. Keith Robinson testified about the police investigation of the alleged rape. Police have complained they were misled when they went to the Kennedy estate April 1 asking for Smith and the senator, but under cross-examination by attorney Mark Schnapp, Robinson agreed Smith had voluntarily provided evidence once they contacted him after he returned to Washington.

Smith, a medical school graduate, drew his own blood for police analysis, Robinson recalled.

In addition to today's session, Ms. Lupo set a half-day session for Sunday as she pushed to wrap up the proceedings before Christmas.

On Friday, Kennedy repeatedly answered, ''No, I did not,'' to questions by prosecutor Moira Lasch about whether he heard any screams or unusual noises while sleeping with his windows open during the time of the alleged rape.

He also recalled the August 1990 death of Smith's father from cancer.

''Steve Smith was Will's father ... ,'' he said. ''Next to a brother to me. I lost a brother in the war. When Jean married Steve we had another brother and when Steve was gone something left all of us when we buried him.''

Kennedy's oldest brother, Joe Jr., was killed in World War II.

The senator also made mention of his ''brother Bob'' during questioning. Sen. Robert F. Kennedy was assassinated as he campaigned for president in 1968. Asked if he was close to his sister Jean, he said: ''We are a very close family. ... We spend a lot of time with her. My sister, Pat, Eunice, have spent time with her. Ethel has. Jackie has. We're a very close family.''

Tears streamed down Smith's face. One of his lawyers leaned over to ask if he was all right and he shook his head yes.

''Obviously, this was a very moving day,'' Smith said outside the courthouse afterward. He added that he thought ''this part of the process has been unfair'' to his uncle.

Kennedy's 24-year-old son, Patrick, a Rhode Island state legislator, took the stand after his father.

The younger Kennedy testified that Smith told him his accuser had acted strangely the morning of the alleged attack - calling him by the wrong name, demanding to see his driver's license and claiming to have been at the estate before.

He also testified that Smith told him the woman said she would call the police.

Mrs. Lasch repeatedly asked the younger Kennedy why he didn't ask Smith why the woman would call the police and why he didn't tell anyone else at the estate about the threat.

''In retrospect, perhaps I should have talked to somebody,'' he said. ''If I knew then what I know now.''