Study reveals joint replacement surgery inequities (Otago University media release)
The provision of publicly-funded hip and knee total joint replacement (TJR) procedures varies between District Health Boards (DHBs) and national rates have not increased since 2007, new University of Otago research has found.
The Dunedin School of Medicine study, which appears in the latest edition of the New Zealand Medical Journal, examined rates of elective TJR procedures between 2006 and 2013.
Study principal investigator Dr Helen Harcombe says that geographically-based inequities emerged from the research.
“Even taking into account age and ethnicity, rates of TJR procedures varied between DHBs, with DHBs covering larger populations tending to have lower rates than smaller ones,” Dr Harcombe says.
The study also showed that while there has been an increase in the number of TJR procedures carried out in the public system between 2007 and 2013, rates are barely keeping pace with a growing population. The number of publicly-funded TJR procedures increased by six percent over this period, but New Zealand’s growing population meant the surgery rate per head of population (aged over 20 years) actually decreased by 0.6 per cent.
The research, funded by Arthritis New Zealand, found that the highest rate of publicly-funded joint replacement procedures was for those aged 75–84 years followed by 65–74-year-olds.
Dr Harcombe says that nearly one-third of New Zealanders aged over 65 are diagnosed with osteoarthritis, which is the most common reason for joint replacement surgery. She notes that 14 per cent of the population is currently in this age group, but this is predicted to increase to 27 per cent by 2063.
“This means demand for TJR surgeries is likely to increase markedly in coming years, and the public health system will need to be adequately resourced to meet future demand.”
Equity of publicly-funded hip and knee joint replacement surgery in New Zealand: results from a national observational study
AIM: This study examines equity in the provision of publicly-funded hip and knee total joint replacement (TJR) surgery in New Zealand between 2006 and 2013 to: 1) investigate national rates by demographic characteristics; 2) describe changes in national rates over time; and 3) compare rates of provision between District Health Boards (DHBs).
METHODS: Hospital discharge data for people aged 20 years or over who had at least one hip or knee TJR between 2006 and 2013 was obtained from the Ministry of Health’s National Minimum Dataset.
RESULTS: Higher TJR rates were observed among those aged 75–84 years, females, those of Māori ethnicity, those not living in rural or main urban areas and those in the most deprived socio-economic groups.
TJRs increased from 7,053 in 2006 to 8,429 in 2013, however the rate was highest in 2007. In 2012–13, age-ethnicity-standardised rates varied between DHBs from 196 to 419/100,000 person years, with larger DHBs having lower rates than smaller DHBs.
CONCLUSION: There was evidence of geographic inequity in TJR provision across New Zealand. Despite increased numbers of procedures, rates of publicly-funded TJR surgery are barely keeping up with population increases. Reasons behind differences in provision should be examined.
How effective is our current Orthopaedic Prioritisation Tool for scoring patients for arthroplasty surgery?
AIM: To compare those patients who are being accepted onto the waiting list for total hip and knee arthroplasty surgery with those patients who are being declined surgery, using a validated functional questionnaire.
METHOD: The clinic records from all patients seen for consideration of total hip or knee arthroplasty at Hawkes Bay Hospital during the preceding four months were reviewed. We sent the Oxford Hip and Knee Score questionnaire to all patients who had been put forward for consideration of surgery.
RESULTS: Of the 150 patients we surveyed, 81 had been accepted onto the waiting list and received a date for surgery within the next four months and 69 had been declined surgery. Of the 81 patients who had been accepted onto the waiting list for surgery, 61 returned the Oxford questionnaire with an average score of 10.9. Of the 69 patients who had been declined surgery, 59 returned the Oxford questionnaire with an average score of 10.8. Thus the mean Oxford score was not statistically different between those patients being accepted onto the waiting list for surgery and those being declined surgery (p=0.925).
CONCLUSION: No difference was found between those patients being accepted onto the waiting list for total hip or knee arthroplasty and those being declined surgery in Hawkes Bay after using the Oxford Hip and Knee Score as a measure of functional impairment. The average Oxford score indicates that patients being seen in Hawkes Bay Hospital for consideration of total hip or knee arthroplasty are severely functionally impaired as a result of their condition.