The percentage of elective surgery requests declined by ACC has doubled since 2007, with shoulder and spinal requests among the most commonly refused.
Figures released to the Otago Daily Times show that in 2007, 11% of the 48,063 surgery requests were declined, compared with 22% of 52,542 in 2009.
In 2009, 11,758 people seeking surgery were turned down, compared with 5062 in 2007.
At the same time as the percentage of refusals has risen, the number of requests has also gone up and the number of people receiving ACC-funded surgery has dropped.
In 2009, the number of patients receiving surgery was 2217 lower than that of 2007.
ACC spokesman Laurie Edwards said the significant increase in the volume of surgery requests had ironically been at a time when overall claim numbers had stabilised or begun to fall.
The proportion of surgery requests declined increased in all age groups since 2007, with most 2009 percentages about double those of two years earlier.
"Certainly the proportion of declined surgery requests increases with age, but that is to be expected since the presence of degenerative conditions is much more likely.
In shoulder surgery, 2009 requests were more than 1500 higher than the number in 2007.
However, the percentage of refusals had increased from 15% in 2007 to 43% last year.
It was a similar story for spinal surgery where the percentage refused had more than doubled from 18% in 2007 to 39% in 2009.
The number of people declined surgery for spinal injuries rose from 605 in 2007 to 1500 last year.
Mr Edwards said some back surgery was declined because ACC's medical advice suggested the condition was primarily degenerative - "and the older a person is, the more likely they are to have a serious degenerative condition, even though they may not have been aware of it prior to the accident".
The data provided on spine, shoulder, knee and hip surgery shows that hip surgery is the only area to have a lower percentage of refusals last year.
These dropped from 42% in 2007 to 32% last year, but the number seeking such surgery had risen from 570 to 812.
The percentage of knee surgery requests declined increased from 11% last year to 16% last year (2007 data was not available)Of the four areas for orthopaedic surgery, this had the largest number of patients involved with 16,097 seeking knee surgery last year.
Tables provided by ACC showed that the proportion of surgery requests ACC declined had increased over all age groups.
In the past three years, the number of reviews being sought by patients increased, but the proportion found in ACC's favour had stayed high.
Mr Edwards said the number of review applications had increased in the past year, roughly in line with the number of decline decisions.
However, ACC did not hold data which showed what individual reviews were about - they could involve both surgery and weekly compensation.
About 65% of review applications were either withdrawn by the client or upheld in ACC's favour, 25% of ACC's decisions were overturned by the reviewer and in 8% of cases ACC changed its decision and approved surgery generally because more information was supplied.
At present it was taking about four months from the time a review application was lodged until the date of a review hearing by an independent reviewer.
Delays could be worsened by the non-availability of relevant participants or the provision of new information which required ACC to reconsider its original decision to decline funding.
