Trust-, Local Health Board- and unit-level activity and outcomes

Outlier units for 90-day mortality and revision rates for the period 2003 to 2016

The observed numbers of revisions of hip and knee replacements for each hospital were compared to the numbers expected given the unit’s case-mix in respect of age, gender and reason for primary surgery. Hospitals with a much higher than expected revision rate for hip and knee replacement have been identified.

These hospitals had a revision rate that was above the upper of the 99.8% control limits (these limits approximate to +/-3 standard deviations). We would expect 0.2% (i.e. one in 500) to lie outside the control limits by chance, with approximately half of these (one in 1,000) to be above the upper limit.

When examined over the life of the registry, a total of 28 hospitals reported higher than expected rates of revision for knee replacement and 41 hospitals had higher than expected rates of revision for hip surgery. However, revisions taken only from the last five years of the registry showed only twelve hospitals reporting higher than expected rates for knees, and five for hips.

The 90-day mortality for hip and knee replacement was calculated for all hospitals by plotting standardised mortality ratios for each hospital against the expected number of deaths. One hospital (closed in 2013) had a higher than expected mortality rate for knee replacement while none were identified for hip replacement.

Note: The case mix for mortality includes age, gender and ASA grade. Trauma cases have been excluded from both the hip and knee mortality analyses together with hips implanted for failed hemi-arthroplasty or for metastatic cancer (the latter only from November 2014 when recording of this reason began). Also, where both left and right side joints were implanted on the same day, only one side was included in the analysis.

Note: Any units identified as potential outliers in Part Four have been notified. All units are provided with an Annual Clinical Report and additionally have access to an online NJR Management Feedback system.

Important note about the outlier hospitals listed below

In previous annual reports, the NJR has reported outlying hospitals based on all cases submitted to the NJR since 1 April 2003. To reflect changes in hospital practices and component use, the NJR now also reports outlying hospitals based on the last five years of data (1 March 2012 to 1 March 2017 inclusive, the latter date being when the dataset was cut). This five year cut of data excludes from the analysis the majority of withdrawn outlier implants, and metal-on-metal total hip replacements, and thus better represents contemporary practice.

Outlier for Hip mortality rates since 2003*
None identified

Outlier for Knee mortality rates since 2003*
Redwood Diagnostic Treatment Centre [closed in 2013]
Outliers for Hip revision rates, all linked primaries from 2003*
Ashtead Hospital (Surrey)
Basingstoke and North Hampshire Hospital BMI Esperance (East Sussex)
BMI Gisburne Park Hospital (Lancashire) BMI Sarum Road Hospital (Hampshire) BMI The Somerfield Hospital (Kent) Clifton Park Hospital (North Yorkshire) Dunedin Hospital (Berkshire)
Homerton University Hospital Llandough Hospital
Maidstone District General Hospital Medway Maritime Hospital Musgrove Park Hospital
Nevill Hall Hospital
New Hall Hospital (Wiltshire) North Downs Hospital (Surrey) North Tyneside General Hospital
Northampton General Hospital (Acute)
Nuffield Health Brighton Hospital (East Sussex)
Nuffield Health Haywards Heath Hospital (West Sussex) Nuffield Health Tees Hospital (Cleveland)
Nuffield Health Wessex Hospital (Hampshire) Nuffield Health York Hospital (North Yorkshire) Pilgrim Hospital

Outliers for Hip revision rates, all linked primaries from 2003*
Prince Charles Hospital
Rotherham District General Hospital Royal Cornwall Hospital (Treliske) Salisbury District Hospital
Shepton Mallet Treatment Centre (Somerset) Spire Cardiff Hospital (Glamorgan)
Spire Gatwick Park Hospital (Surrey) Spire Tunbridge Wells Hospital (Kent) St Albans City Hospital
St Michael's Hospital
Sussex Orthopaedic NHS Treatment Centre The Royal London Hospital
University Hospital (Coventry) University Hospital Of Hartlepool University Hospital Of North Tees Watford General Hospital
York Hospital

Outliers for Hip revision rates, all linked primaries from 2012**
Homerton University Hospital 
Southampton General Hospital 
St Richard's Hospital
Watford General Hospital 
Weston General Hospital

Outliers for Knee revision rates, all linked primaries from 2003*
BMI Bishops Wood Hospital (Middlesex) 
BMI Goring Hall Hospital (West Sussex) 
BMI The Meriden Hospital (West Midlands) 
Bradford Royal Infirmary
Cannock Chase Hospital 
Charing Cross Hospital 
Conquest Hospital 
County Hospital Louth 
Good Hope Hospital 
Hinchingbrooke Hospital
Horton NHS Treatment Centre (Oxfordshire) 
Hospital Of St Cross
James Paget University Hospital
King Edward VII Hospital Sister Agnes (Greater London) 
Llandough Hospital
New Hall Hospital (Wiltshire) 
Peterborough City Hospital 
South Tyneside District Hospital 
Southampton General Hospital 
Southmead Hospital
Spire Alexandra Hospital (Kent) 
Spire Clare Park Hospital (Surrey)
Spire Southampton Hospital (Hampshire) 
St Albans City Hospital
St Richard's Hospital 
University College Hospital 
Withybush General Hospital

Outliers for Knee revision rates, all linked primaries from 2012**
Ashford Hospital
BMI The London Independent Hospital (Greater London) 
BMI The Meriden Hospital (West Midlands)
Broadgreen Hospital 
County Hospital Louth 
Ealing Hospital
King Edward VII Hospital Sister Agnes (Greater London) 
North East London NHS Treatment Centre (Essex) 
Spire Southampton Hospital (Hampshire)
St Richard's Hospital 
University College Hospital 
West Cumberland Hospital

Better than expected performance

This year we have also listed hospitals where revision rates are statistically better than expected. These are units that lie below the 99.8% control limit.

Better than expected for Hip revision rates, all linked primaries from 2003*
Addenbrooke's Hospital Alexandra Hospital
Bedford Hospital South Wing Bishop Auckland Hospital
BMI Mount Alvernia Hospital (Surrey)
BMI Sandringham Hospital (Norfolk)
BMI The Edgbaston Hospital (West Midlands) 
Chapel Allerton Hospital
Claremont Hospital (South Yorkshire) 
Emersons Green NHS Treatment Centre (Avon) 
Euxton Hall Hospital (Lancashire)
Glenfield Hospital [closed 2012] 
Goole and District Hospital (Acute) 
Harrogate District Hospital 
Hereford County Hospital
Ipswich Hospital
Kidderminster Treatment Centre 
Leicester General Hospital
London Road Community Hospital [closed 2009] 
New Cross Hospital
Northern General Hospital
Nottingham Woodthorpe Hospital (Nottinghamshire) 
Nuffield Health Brentwood Hospital (Essex)
Nuffield Health Cambridge Hospital (Cambridgeshire) 
Nuffield Health Derby Hospital (Derbyshire)
Nuffield Health Exeter Hospital (Devon)
Nuffield Health Hereford Hospital (Herefordshire) 
Nuffield Health Ipswich Hospital (Suffolk)
Nuffield Health Leicester Hospital (Leicestershire) 
Nuffield Health North Staffordshire Hospital (Stafordshire) 
Nuffield Health Wolverhampton Hospital (West Midlands) 
Prince Philip Hospital
Princess Alexandra Hospital 
Queen Alexandra Hospital
Queens Hospital Burton Upon Trent
Queens Medical Centre Nottingham University Hospital 
Royal Derby Hospital
Royal Devon & Exeter Hospital (Wonford)
Royal Hospital at Haslar Treatment Centre [closed 2012] 
Royal Stoke University Hospital
Royal Surrey County Hospital 
Russells Hall Hospital
Spire Parkway Hospital (West Midlands) 
Spire Portsmouth Hospital (Hampshire) 
St Mary's Hospital
The Cheshire and Merseyside NHS Treatment Centre [closed 2011]
The Great Western Hospital 
The Princess Royal Hospital 
West Suffolk Hospital 
Wrightington Hospital

Better than expected for Hip revision rates, all linked primaries from 2012**
Addenbrooke's Hospital 
Calderdale Royal Hospital 
Ipswich Hospital
Royal Devon & Exeter Hospital (Wonford) 
Royal Surrey County Hospital

Better than expected for Knee revision rates, all linked primaries from 2003*
Bishop Auckland Hospital Blackpool Victoria Hospital
BMI Beardwood Private Hospital (Lancashire) BMI Huddersfield (West Yorkshire)
BMI Three Shires Hospital (Northamptonshire) Bronglais General Hospital
Chapel Allerton Hospital City Hospital
Clifton Park Hospital (North Yorkshire) Darlington Memorial Hospital Glenfield Hospital [closed 2012] Ipswich Hospital
London Road Community Hospital [closed 2009] New Cross Hospital
Nuffield Health Derby Hospital (Derbyshire) 
Nuffield Health Ipswich Hospital (Suffolk) 
Nuffield Health Leeds Hospital (West Yorkshire) 
Nuffield Health York Hospital (North Yorkshire) 
Princess Alexandra Hospital
Queen Elizabeth Hospital Woolwich 
Queens Hospital Burton Upon Trent 
Rivers Hospital (Hertfordshire) 
Royal Bournemouth Hospital
Royal Derby Hospital
Royal Orthopaedic Hospital
Royal Stoke University Hospital 
Russells Hall Hospital
Sandwell General Hospital
Spire Hartswood Hospital (Essex) 
St Woolos Hospital
Stepping Hill Hospital 
Wansbeck Hospital 
Worcestershire Royal Hospital 
Wrightington Hospital

Better than expected for Knee revision rates, all linked primaries from 2012**
Bishop Auckland Hospital 
Burnley General Hospital 
Calderdale Royal Hospital 
New Cross Hospital
North Tyneside General Hospital 
Princess Alexandra Hospital 
Queens Hospital Burton Upon Trent 
Royal Derby Hospital

*Date range 1 April 2003 to 1 March 2017 inclusive
**Date range 1 March 2012 to 1 March 2017 inclusive

Implant- and unit-level activity and outcomes 2016

Part Four of the annual report gives performance and data entry quality indicators for Trusts, Local Health Boards (many of whom comprise more than one hospital) and independent (private) providers in England, Wales, Northern Ireland and the Isle of Man for the 2016 calendar year. Outcomes analysis after hip and knee replacement surgery is also provided for the period 2003 to 2016. This section now also provides data for implant outliers since 2003 and further information on notification and last usage date.

Clinical activity

Overall in 2016, 150 NHS Trusts and Local Health Boards (comprising 247 separate hospitals) and 177 independent hospitals were open and eligible to report patient procedures to the NJR. All units except for three trauma units submitted data in 2016.

The proportion of all hip and knee joint replacements entered in to the NJR against those carried out (compliance) is only available by NHS Trust and Local Health Board. No data on this is currently available from private providers and figures would also exclude units in Northern Ireland as compliance is not available.

• 26% of NHS providers reported 95% or more of the joint replacements they undertook
• 54% of NHS providers reported between 80% and 95%
• 20% of NHS providers reported less than 80%

Of those hospitals submitting data, the proportion of patients who gave permission (consent) for their details to be entered into the NJR were:

NHS hospitals

• 48% of NHS hospitals achieved a consent rate of greater than 95%
• 34% achieved a consent rate of 80% to 95%
• 18% recorded a consent rate of less than 80%

Independent hospitals

• 70% of independent hospitals achieved a consent rate greater than 95%
• 21% achieved a consent rate of 80% to 95%
• 8% recorded a consent rate of less than 80%

Similarly, the proportion of entries in which there is significant data to enable the patient to be linked to an NHS number (linkability) are listed below:

NHS hospitals

• 87% achieved a proportion of patients with a linkable NHS number greater than 95%
• 11% achieved a proportion of 80% to 95%
• 2% recorded a proportion of linkable records of less than 80%

Independent hospitals

• 72% achieved a proportion of patients with a linkable NHS number greater than 95%
• 21% achieved a proportion of 80% to 95%
• 6% recorded a proportion of linkable records of less than 80%

Note: Independent hospitals might be expected to have lower linkability rates than NHS hospitals, as a proportion of their patients may come from abroad and not have an NHS number. Linkability figures are not currently available for Northern Ireland or the Isle of Man.

Trust-, Local Health Board- and unit-level activity and outcomes 2016

Part Four of the annual report gives performance and data entry quality indicators for Trusts, Local Health Boards (many of whom comprise more than one hospital) and independent (private) providers in England, Wales, Northern Ireland and the Isle of Man for the 2016 calendar year. Outcomes analysis after hip and knee replacement surgery is also provided for the period 2003 to 2016.

This section now also provides data for implant outliers since 2003 and further information on notification and last usage date.