One of the most commonly cited advantages of hip resurfacing is the technical ease of revision surgery on the femoral side of the joint. It is therefore reasonable to suggest that such surgery ought to be associated with reduced operative times, reduced blood loss and more rapid mobilisation than conventional hip revision. However, there is little objective evidence in the literature to support this view.

In our own unit, 6 consultants have now revised 15 hip resurfacings (13 Corins and 2 MMT Birmingham Hip Resurfacings). A retrospective study of the hospital records was performed to compare three well recorded parameters 1) On table operative times 2) Post Operative blood transfusion requirement 3) In patient length of stay.

Average on table time was 195 minutes for conventional THR revision and 120 minutes for revision of resurfacing i.e. a 1 third reduction in theatre time for resurfacing with attendant advantages in costs and risks. However, post operative length of stay was little different between the two groups.

Average blood transfusion requirement was 4.6 units for conventional THR revision (n=190) and 0.9 units for revision of resurfacing. However, these crude figures do not take into account the difference in physiological state between the two groups of patients. A more complex comparison of age matched revision THR patients shows and average transfusion requirement of 1.8 to 2.2 units for revision of THR versus 0.9 units for revision resurfacing.

In conclusion, there is now objective evidence of the advantages of resurfacing in the revision situation but that these advantages are more modest than those anticipated.

In recent years there has been a resurgence of interest in the concept of hip resurfacing. Since 1996, we have treated 60 patients (65 hips) with the Corin Hip Resurfacing.

Of the 65 primary procedures, 13 have now required revision. 1 case was complicated by early deep infection and 12 (17%) for mechanical failure. 5 of these patients were male and 8 female. Mean time to failure was 11 months (range 48 hours to 53 months). 8 out of the 12 mechanical failures required revision within 6 months of the primary procedure. Mean age of the revision patients was 57 years (range 22 – 71 years).

The most common failure modality (6 cases) was fractured neck of femur. 4 out of 6 of these cases occurred in women over 60 years of age. All of these fractures occurred without a specific history of trauma. Since only 12 patients were women over 60, 1 in 3 women over 60 years of age in our series were complicated by fractured neck of femur.

In 4 cases, the indication for revision was acetabular loosening. One patient had ongoing pain of unknown aetiology and one developed progressive avascular necorsis of the femoral head with subsequent collapse.

Of the 12 cases requiring revision for mechanical failure, two cases required revision of the femoral component only and this was performed using the stemmed modular CTI prosthesis produced by Corin for this purpose. Three cases required revision of the socket only and the others were revised to total joint replacement. The one case of early deep infection was treated by two stage revision. There were no dislocations in our series and there was no evidence of metallosis.

Not for the first time in the history of orthopaedics, a DGH has been unable to repeat the excellent results reported by a specialist centre with a new technique. However, analysis of the above data has led us to believe that our results may be much improved by careful patient selection. It is also apparent that formal revision strategies need to be developed for hips resurfacing.