Hospitalisation and the treatment of osteoarthritis

At present there is no cure for osteoarthritis. A variety of procedures are performed in hospitals to restore joint function, help relieve pain and improve quality of life for someone with osteoarthritis. For people unresponsive to medication, joint replacement surgery is a cost-effective intervention [1].

Based on the AIHW National Hospital Morbidity Database (NHMD), in 2014–15:

  • there were 111,053 hospitalisations with a principal diagnosis of osteoarthritis
  • there were more hospitalisations for osteoarthritis per 100,000 population for females (509 per 100,000) than males (431 per 100,000)
  • the hospitalisation rate was higher for males than females up to the age of 50–54, above which the rate was higher for females
  • the hospitalisation rate increased with age until the age of 75–79, after which it fell.

Figure 1: Rate of hospitalisation for osteoarthritis by sex and age, 2014–15

The vertical bar chart shows that in 2014–15, the hospitalisation rate for the principal diagnosis of osteoarthritis was higher for males up to the of 50–54, above which the rate was higher for females. The hospitalisation rate increased with age until the age of 75–79 after which it fell.

Source: AIHW National Hospital Morbidity Database (Data table).

The age-standardised hospitalisation rate for Australians with osteoarthritis increased in the 10 years from 2005–06 to 2014–15: from 371 hospitalisations per 100,000 population to 413 per 100,000 population. There was a slightly larger increase for females.

Figure 2: Age-standardised rate of hospitalisations for osteoarthritis, by sex, 2005–06 to 2014–15

 

The line chart shows that age-standardised hospitalisation rates for osteoarthritis as the principal diagnosis increased between 2005–06 and 2014–15. In 2005–06 hospitalisation rates for osteoarthritis were 371 per 100,000 population, increasing to 413 per 100,000 population in 2014–15. There was a slightly larger increase for females.

Note: Rates are age-standardised to the Australian population as at 30 June 2001.

Source: AIHW National Hospital Morbidity Database (Data table).

Knee and hip replacements

Joint replacement surgery is a cost-effective intervention for people with severe osteoarthritis and those unresponsive to medication [1]. These procedures restore joint function, help relieve pain and improve quality of life of the affected person.

The number of total joint replacements where osteoarthritis was the principal diagnosis increased over the 10 years to 2014–15. The age standardised rate of knee replacement increased by 29% from 133 to 172 per 100,000 population. The rate of hip replacements increased by 31% from 81 to 106 per 100,000 population.

Figure 3: Trends in total knee and hip replacements for osteoarthritis, 2005–06 to 2014–15

The line chart shows that age-standardised rate of knee replacement for ostoearthritis as the principal diagnosis increased by 29%25 from 133 per 100,000 population in 2005–06 to 172 per 100,000 population in 2014–15. The rate of hip replacement increased by 31%25 from 81 to 106 per 100,000 population.

Note: Rates are age-standardised to the Australian population as at 30 June 2001.

Source: AIHW National Hospital Morbidity Database (Data table).

In 2014–15, 75,692 total hip and knee replacements were performed in people with a principal diagnosis of osteoarthritis (47,087 knee replacements and 28,605 hip replacements). The rate of knee or hip replacements was highest among men and women aged 75–79 years.

Figure 4: Rate of total knee and hip replacements for osteoarthritis, by age, 2014–15

The vertical bar chart shows that in 2014–15, the rate of knee or hip replacements was highest among men and women aged 75–79 years.

Source: AIHW National Hospital Morbidity Database (Data table).

Joint replacements do not last forever, so some people will require revision surgery. Based on data from the Australian Orthopaedic Association National Joint Replacement Registry [1], there were 4,307 revision hip replacements and 4,104 revision knee replacements reported in 2014. There is about a 5% chance of revision surgery within 10 years of a hip or knee replacement.

Between 2003 and 2014, revision hip replacement increased by 19.2% in the private sector and 33.8% in the public sector. Over the same period, revision knee replacements increased 78.1% in the private sector and 75.3% in the public sector [1].

Second revisions of knee and hip replacements occurred in more than 20% of people who had a first revision. Second revisions were more likely to occur in people aged 70 or under [1].

References

  1. AOA (Australian Orthopaedic Association) 2015. Australian Orthopaedic Association National Joint Replacement Registry. Annual Report. Adelaide: AOA.
  2. NCCC (National Casemix and Classification Centre) 2012. The international statistical classification of diseases and related health problems, 10th revision. Australian modification (ICD-10-AM), Australian Classification of Health Interventions (ACHI) and Australian Coding Standards (ACS), 8th edn. Wollongong: University of Wollongong.