A number of popular hip implants are in the health regulator's sights, with more patients than expected ending up in hospitals needing replacements.

Eight implants — five hip, two shoulder and one ankle — have been identified by the Therapeutic Goods Administration as having higher-than-expected revision rates.

That means more Australian patients have had to go back into hospital and have new implants put in.

The affected implants are: Ankle S.T.A.R/S.T.A.R Combination Hip Delta-One-TT Acetabular Component

Delta-One-TT Acetabular Component Furlong Acetabular Component

Furlong Acetabular Component Metafix/Trinity Combination

Metafix/Trinity Combination Profemur L/Dynasty Combination

Profemur L/Dynasty Combination Taperloc Microplasty/Regenerex Combination Shoulder DeltaXtend/DeltaXtend Combination

DeltaXtend/DeltaXtend Combination GlobalUnite/GlobalUnite Combination Source: Therapeutic Goods Administration

Kathy Griffiths from Canberra had to endure a second painful procedure after having her hip replaced in 2013.

The morning after her initial surgery, Ms Griffiths woke to the news that her left thigh bone had accidently broken during the surgery — a side effect often associated with hip replacements.

While her doctors were confident the broken leg would heal, there was another complication.

"The cement used to fix the prosthesis leaked out and it was like a beehive formed around my leg," Ms Griffiths said.

Her leg and hip never healed properly, and while reluctant to undergo a second operation, Ms Griffiths decided she had no choice.

"While I really didn't want to go through it again, I had faith in the surgeon and his judgement and that it was the only way to get back to where I was beforehand," she said.

Professor Richard de Steiger, a member of the Australian joint registry, said as with all medical procedures, there was an element of risk in revision surgery after a device implantation.

He said some implants were fracturing, becoming dislocated, or parts were working loose, causing more patients to end up back in hospital.

"Only 3 or 3.5 per cent of all implants do not have the same success rate that other implants and prostheses have, and it's this group the TGA are looking at," he said.

"There are a variety of reasons causing these revision rates but there is no need for patients to be alarmed and need implants removed."

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Experts are particularly concerned about how several of the hip implants are inserted.

Two of the implants identified by the TGA were inserted by surgeons from the front rather than the side of the hip, leading to a higher chance of the implant fracturing when inserted.

Experts say the Metafix/Trinity Combination implant and the Furlong Acetabular implant have a high failure rate just two weeks after the surgery, which could indicate problems in the design or surgical approach.

Maurice Blackburn class actions lawyer Julian Schimmel, who represented patients in the recent DE Puy hip implant class action, said the poor performance rate of those two implants could lead to them being recalled.

"Just two weeks after the operation we are seeing high revision rates, that to me says there is a design problem," Mr Schimmel said.

Sydney orthopaedic surgeon Dr Munjed Al Muderis said he believed the problem was not the implant itself, but the training of surgeons putting it in.

"It is not the implant, but the surgeon factor which is the problem," he said.

"The anterior [or frontal] approach has become very popular lately as it is more attractive, with a smaller cut. However there isn't widespread proper training for this technique."

Some doctors have called for a complete overhaul of how implants are approved for use in Australia.

"I have spoken to other surgeons and they too are calling for new implants or new approaches to be trialled in a smaller control group in the private sector, not open for two years in the public system," Dr Al Muderis said.

The Therapeutic Goods Administration is reviewing the report and a decision to monitor the implants more closely or remove the items on the list will be made by early in the new year.