A 39-year-old East Boston man is accused of sexually assaulting a patient in an exam room at the MGH Back Bay Health Center, according to police.

Damien Knighton has been charged with rape and indecent assault and battery following the Wednesday afternoon alleged assault.

The patient had gone into MGH Back Bay Health Center on Commonwealth Avenue to see his doctor for a follow-up appointment for an injury to his shoulder and leg.

The patient told police he was approached by the medical assistant, Knighton, who said the doctor requested an additional test. Prior to the test, Knighton asked the patient to remove his clothes and told the patient he would be examining his penis and testicles.

Knighton then allegedly moved the patient’s penis side to side, touched his testicles, and asked if blood was rushing to his penis. The medical assistant then allegedly inserted his finger into the patient’s rectum.

Knighton then asked him to turn around and allegedly repeated the insertion for a second time.

The patient then got dressed and asked other staff about the exam. The patient concluded that he was sexually assaulted and called 911.

“Patients entering an exam room have every expectation of receiving proper medical attention and proper ethical treatment,” said Suffolk DA Kevin Hayden. “This incident presents an egregious violation of those expectations. I’m grateful the victim made authorities aware of what happened to him.”

Knighton has been ordered held on $5,000 bail, and he was ordered to have no contact with the victim and no unsupervised access to patients.

Knighton is set to return to court on Feb. 23 for a probable cause hearing.