Abstract
Orthopaedic practice is increasingly guided by conclusions drawn from analysis of Joint Registry Data. Analysis of the England and Wales National Joint Registry (NJR) led Sibanda et al to conclude that UKR should be reserved for more elderly patients due to higher revision rates in younger patients. To determine our UKR revision rates at the Great Western Hospital we requested knee arthroplasty data from the NJR, Hospital Episode Statistics (HES) data submitted by our centre to the Primary Care Trust, and interrogated our internal theatre implant database. This revealed significant discrepancies between different data sources.
We collected data from each source for 2005, 2006, and 2007. Operations were classified as TKR, UKR, Other or Unspecified. Results are illustrated in the attached table:
Key findings:
Our theatre implant database appears most accurate and includes a greater number of joint replacement operations than NJR or HES data and fewer ‘unspecified’ procedures.
On average 15% NJR, 0% HES and 0.3% theatre data procedures were ‘unspecified’.
NJR data comprises an average 17 fewer, and HES data an average 36 fewer procedures each year compared with our theatre data.
Up to 80% UKRs performed are recorded as TKR in HES data.
In summary there is significant inaccuracy in our NJR data which may affect the validity of conclusions drawn from NJR data analysis. HES data is even less accurate with implications for hospital funding. We strongly advise other centres to continue to maintain accurate implant data and to perform a similar audit to calculate error rates for NJR and HES data. Further analysis is required to identify at which stage of data collection inaccuracies occur so that solutions can be devised. We are currently analysing data from 2008 and 2009.
