At least a quarter of people who have been injured in the Gaza Strip since the Israeli war broke out last year have "life-changing injuries," according to new data from the World Health Organization (WHO).

That total - 22,500 people as of late July, and likely closer to 24,000 today, officials said - is mostly made up of people whose limbs were amputated or otherwise severely injured. But some also have spinal cord injuries, traumatic brain injuries, and major burn injuries.

The WHO considers the injuries to be life-changing if people continue to need rehabilitation services in the long term.

"The huge surge in rehabilitation needs occurs in parallel with the ongoing decimation of the health system," Rik Peeperkorn, the WHOs representative for the Palestinian territories, said in a statement.

Pointing to a fresh analysis of the types of injuries resulting from the conflict, the UN health agency said "many thousands of women and children" figured among those badly injured and that many had suffered more than one injury.

It estimated there had overall been between 13,455 and 17,550 "severe limb injuries", which it said were the main driver of the need for rehabilitation.

The report also showed that between 3,105 and 4,050 limb amputations had occurred.

At the same time, WHO said only 17 of Gazas 36 hospitals are currently even partially functional, while primary health care services are frequently suspended or inaccessible due to insecurity, attacks and repeated evacuation orders.