Thirty-one frail, elderly people who suffered broken hips when violently tossed around by the Christchurch earthquake had major surgery to repair the injury in the city's public hospital.

A broken hip, serious for a person of any age, is far more serious for the elderly. Around a quarter of elderly fractured-hip patients do not survive beyond a year.

Some of these patients, who now need more care because of their surgery, are caught up in the region's resthome bed shortage - more than 600 beds have been lost because of the quake.

"They can't go home because they're not well enough to, or their home is not fit for them to go home, and they don't have resthomes to go to," Christchurch Hospital orthopaedic surgeon Andrew Vincent said yesterday. "Patients are being transferred out of Christchurch and that could be ongoing."

He said the earthquake workload was intense for the hospital's orthopaedics department, which received help from other hospitals, but the types of operations were not unusual, apart from the large number of crush injuries.

In total, 130 earthquake injury victims had orthopaedic surgery at Christchurch Hospital in the week after the February 22 quake that smashed large sections of the city and much of its infrastructure. Others were taken to hospitals in other cities.

The Accident Compensation Corporation said yesterday that by last Saturday it had received 7133 quake-related injury claims. The most common injury was to the lower back or spine, accounting for 15 per cent of claims. Sixty-seven per cent of claims were for soft tissue injuries such as bruising, strains and sprains.

Mr Vincent, in Auckland yesterday to address an Orthopaedic Association meeting on surgery during the disaster, said repairing the broken hips of elderly people was the most common operation.

"Half to two-thirds we fixed with a plate and screws; the rest we did a partial or full hip replacement."

Mr Vincent treated Brian Coker, the financial adviser trapped in the collapsed Pyne Gould building whose legs had to be amputated in the rubble. That life-saving operation was done by Christchurch anaesthetist Bryce Curran and Australian urologist Lydia Johns Putra using a Leatherman fold-out knife and a tradesman's hacksaw.

Mr Vincent said Mr Coker, 52, had received excellent care in the "field operation". The operation in hospital was to prevent infection.

Mr Coker was transferred to Waikato Hospital to recuperate. A spokeswoman said he was discharged home last Friday.

Mr Vincent said some of the more severely crushed patients had many operations.

One of the patients admitted to the orthopaedics department had died, an elderly patient with a hip fracture.

Some of the crush injury victims were still in the intensive care unit being treated for kidney failure.

130 orthopaedics operations for earthquake injuries at Christchurch Hospital in the week after the earthquake, including:

* 31 elderly patients had a broken hip

* 12 patients with a fractured spine

* 12 with a fractured pelvis

* 12 fractured thigh or shin bones

* 9 crush injuries, of whom 3 had both legs amputated and 2 lost one leg

* 20 arm or shoulder fractures12fractured ankles