In June 2021, the woman, who was said to be at risk of harming herself, became agitated, kicking and hitting her cell door and wall with a book to get the attention of custody staff.
When they approached and opened the cell, the woman slipped out of the cell and ran down the hall.
One worker grabbed her arm before another took the woman down to the ground.
CCTV footage showed the worker sweeping her legs from under her, with her head narrowly missing a wall.
The footage also showed the woman unable to take any weight on the sore leg, with neither officer physically examining her ankle.
She immediately complained about the pain and a staff member was said to have phoned the duty doctor, who said the injury was not serious, and to give Panadol.
"I continued to ask to see a doctor, but I was spoken to disrespectfully and denied the right," the woman told the IPCA.
"They told me a doctor didn't need to be called and my injury was not serious."
A document taken by one of the custody staff members tried to cover the incident up, blaming her behaviour from earlier on in the night.
"Hurt foot kicking door bit swollen – called Dr - says to give Panadol – no serious injury."
The next morning she was taken to the hospital where she was diagnosed with a fractured ankle that required surgery.
Police have acknowledged and accepted the findings.
"In this instance, we have fallen short of these expectations and standards," Manukau District Commander Superintendent Shanan Gray said.
"As an organisation, we are always open to learning to find improvements to better inform Police and other key decision-makers around the management of detainees."
Doherty also raised concerns about the woman being mistreated because of her identification - she was formally identified and called by a male name.
"This does raise concerns about the attitude of the Police staff towards her and possibly the culture of the Custody Unit."
One Custody staff member involved has since left New Zealand Police.