A healthcare assistant, identified only as "Ms C" in the report, grabbed the woman's upper arms and slapped her upper thigh during a night shift.
Following breakfast the next morning, the woman was unable to walk, which was unusual. A nurse examined her left leg and found it was swollen and shiny and contacted the woman's GP.
Two days later, the woman's family took her to a public hospital, from which she was discharged the next day, to the care of her family. She died early last year.
Ms Wall says a second healthcare assistant saw and overheard the abuse of the woman, but did not report the incident overnight and did not complete an incident form.
The morning after the assault, a third healthcare assistant reported - to the nurse - that there were bruises on the woman's body.
"While it was noted that Mrs A [the elderly woman] had finger-mark bruises on her upper arms, the incident report completed did not refer to other details such as Mrs A's complaints that the bruising was caused by a staff member, or that she had been 'bashed on the knee'."
"In mid-2013, there had been an allegation of Ms C physically abusing another resident at CHT. CHT had investigated the allegation, and Ms C had remained in the employment of CHT and undergone further training and supervision."
Ms Wall says the private hospital's initial care plan and incident reports did not contain adequate information. The care plan was not updated to take into account changes in the woman's condition and medication management was sub-optimal. Staff failed to assess the woman's injuries adequately and failed to manage them appropriately.
The deputy commissioner also criticised the hospital for not providing Ms C with training about abuse and neglect after the mid-2013 incident, and for the second healthcare assistant's failure to properly report the physical abuse of Mrs A at the time.
"People with dementia can be particularly vulnerable to abuse," Ms Wall says, "and the fact that the person has dementia can make it harder to establish whether abuse is taking place, and by whom."
There was a marked power imbalance between the woman and the healthcare assistant who physically abused her and the healthcare assistant's response to the situation was "clearly inappropriate" and "a very serious departure from fundamental professional and ethical standards".
" ... we are sorry for the stressful situation Mrs A's family has experienced as a result of the alleged incident," said CHT's chief executive, Max Robins.
CHT had managed the situation quickly.
" ... we were disappointed with the findings of the inquiry, given the very good record we have over our 53-year history of providing great care for older people."