Shirley Robinson, 76, of Pulborough, was walking along Lower Street, Pulborough, on August 16 last year, when she fell off the pavement, into the path of a lorry.
Despite the quick intervention of two nurses, who were nearby, Mrs Robinson sadly died at the scene.
The inquest heard from lorry driver, Philip Bacon, who described the moment he saw a “blur” in his wing mirror, and seconds later, a “bump”.
Nick Winfield, a car driver who witnessed the incident, said: “The lady fell off the pavement, into the road, and I think I saw the wheel go over her.
“The driver was in a state of shock, but there was nothing he could have done.”
A post-mortem revealed Mrs Robinson had suffered multiple fractures and a laceration of the heart.
Shortly after the incident, collision investigators from Sussex Police were called to survey the scene.
They noticed a manhole cover, which was rocking, and that the surrounding Tarmac had dipped lower than the edge of the cover.
Suspecting this had caused Mrs Robinson to trip, they contacted Jonathan Ullmer, of West Sussex County Council Highways, to assess the scene.
The inquest heard how the site was routinely inspected every month, and had been three weeks prior to the incident.
Under repair guidelines, any defect in a pavement which is greater than 20 millimetres deep must be repaired within 28 days.
The amount the manhole cover rocked was recorded by police as 24 millimetres.
Mr Ullmer said his inspectors had noted “minor deterioration” of the pavement, but it had not fallen below levels which trigger intervention.
He said: “Within that three weeks, a vehicle could have driven over it to cause the damage.
“It’s possible officers did not pick it up but I would be surprised.”
Recording a narrative verdict, assistant deputy coroner Karen Henderson stated her intention to write a letter to highways department directors.
Under a coroner’s powers, they are entitled to write a Rule 43 letter – a report of the circumstances around the death.
It is sent to the relevant authority, and they must reply within 56 days with an action plan.
The coroner said: “I find Mrs Robinson tripped. She tripped on or around a loose manhole cover.
“The state of the cover was unsatisfactory. I find it is unlikely there was damage in the three-week period.”
Speaking after the inquest, Mrs Robinson’s brother, David Aylwin, said: “Shirley, a retired ward sister at the Westminster Children’s Hospital, will be missed by the family and by the residents of Riverside Court where they lived for many years.
“In recent months she was caring for her husband, Peter. Sadly, he died just four weeks after the accident.”