Introduction: Although good mid-term results have been reported with some metal on metal hip replacements, reported complications due to metal on metal (MOM) related reactions are a cause for concern. We have assessed the clinical outcome and MRI metallic artefact reduction sequence (MARS) findings in a consecutive series of patients with a large head metal on metal hip replacement.

Methods: 62 ASR XL Corail THRs and 17 ASR resurfacings were performed at our hospital between 2005 and 2008. All patients were reviewed and assessed with an Oxford hip score (OHS), a plain radiograph and a MRI imaging was obtained on 76 (96%) hips. Implant position was assessed using Wrightington cup orientation software.

Results: At a mean follow up of 32 months, 9 (15%) ASR XL Corail THRs, and 2(12%) ASR resurfacings had been revised. 10 revisions were performed for MRI confirmed MOM related pathology. Histology confirmed a MOM reaction in all 10 cases.

Of the 76 hips that were MRI scanned, 27 (36%) had typical features of a MOM reaction. These were classified as mild in 10 (13%), moderate in 13 (17%) and severe in 4 (5%).

78 patients completed an OHS and the mean score was 21. The mean OHS was 29 pre-operatively in those that had been revised, 25 in patients with abnormal MRI findings and 20 in those with a normal MRI. 10 patients with abnormal MRIs had a near perfect OHS (15 or less)

Conclusions: The ASR XL Corail THR has an unacceptably high early failure rate. MARS MRI is able to detect metal debris related soft tissue pathology around metal on metal THRs. These lesions are sometimes asymptomatic. We suggest that MARS MRI evaluation should form part of the routine evaluation of all metal on metal THRs, and in particular of this implant.

Introduction: With the rising number of primary hip arthroplasties performed each year, patient selection criteria is becoming increasingly pertinent. There is growing concern that patients with a high body mass index (BMI) have worse outcomes following hip replacement surgery. However the evidence base is equivocal.

Our aim is to assess whether BMI has an impact on clinical and radiological outcomes of primary total hip arthroplasties

Methods: This is a prospective study of 92 patients, undergoing primary total hip arthroplasty, recruited from two hospitals. Data was collected by the operating surgical team and independent physiotherapists at the preoperative assessment clinic, intraoperatively and at six weeks post-operative follow up.

BMI was recorded. Patients were divided into 2 groups: those with a BMI less than 30 (considered nonobese) and those 30 or above (obese).

Outcomes assessed included blood loss and requirement blood transfusion, fat thickness, operation duration, complications and surgeon’s perception of the difficulty of operation (scored on a VAS). In addition functional capacity was assessed using the Oxford Hip scores pre and post-operatively. Radiographs were scored independently according to Dorr and Barrack.

Results: Of our 92 patients, 36 were obese and 56 were non-obese. There was no significant difference found in blood loss, blood transfusion requirements, operation duration and complications between the two groups, With regards to the Oxford Hip scores, the obese patients had greater differences between their pre- and post-operative scores but this difference was not significant (p=0.09). We found a significant difference (p=0.003) in surgeons’ perception of the difficulty of operation with VAS scores for obese patients being higher than non-obese patients. Our Dorr and Barrack scores revealed no significant difference in radiological outcome between our two groups.

Conclusion: Our study would suggest that obese patients do not have worse outcomes following primary total hip arthroplasty than non-obese patients.

Hip resurfacing has in recent years become increasingly popular as an arthroplasty technique, particularly amongst younger patients with more active lifestyles. The procedure has been heralded as a more conservative option, aimed at those wishing to continue strenuous work and recreational activities. In the populalapress and the internet, many claims are made regarding aspects of this procedure, but little evidence has appeared in the scientific literature, either with the results of resurfacing or comparing resurfacing to conventional total hip arthroplasty.

We compare the outcomes of a consecutive series of 44 hybrid hip resurfacings against a similar series of 50 conventional hybrid hip arthroplasties (THR’s), all performed in patients aged 60 or under by a single consultant Surgeon. Data on operation time, blood loss, and length of stay, as well as complications, were all prospectively recorded. A modified Harris Hip score was also documented preoperatively, as well as at 6, 26 and 52 weeks postoperatively. In the resurfacing group, there were 28 Male and 16 female, mean age 47.6 years. In the THR group, there were 22 male and 28 female patients, of mean age 51.9 years. The results for the two groups were analysed, and p value of < 0.05 was taken as statistically significant.

The results showed no difference in operation time or blood loss. There was a small reduction in average length of stay from 7.1 to 6.4 days, which was not clinically significant, while the Modified Harris Hip Scores at 6 and 52 weeks were the same for both groups. We conclude that whilst it has been previously shown that there is an overall preservation of bone stock following resurfacing arthroplasty, there is no evidence to back additional claimed benefits.