Introduction: Hip resurfacing is a successful pain-relieving procedure which restores function in young patients. However, some patients have persisting pain. We suggest that load characteristics in relation to position of the cup may influence these symptoms. We aimed to determine the effect of acetabular cup inclination angle on pain following hip resurfacing.

Methods: 92 consecutive hips in 81 patients were resurfaced with the ASR prosthesis. The average age was 56.5 years (35–72). 33 were female hips. Harris Hip Scores (HHS) and UCLA activity scores were recorded pre-operatively and at last follow-up. Patient satisfaction was recorded. Acetabular cup inclination angle was measured. An acceptable angle for hip replacement is 45 degrees +/− 5 degrees. We therefore grouped cups into those above 50 degrees and those below. Average follow-up was 17.9 months (8–31). There were 39 hips with an angle less than 50 degrees (A), and 53 greater than 50 (B). Patients in each group were comparable for age, sex, follow-up and BMI.

Results: In group A HHS improved from 53.4 to 98.7 and UCLA activity score improved from 4.2 to 7.5. All patients were extremely or very pleased. In group B HHS improved from 49.0 to 94.0 and UCLA activity score improved from 3.9 to 7.1. 48 of 53 patients were extremely or very pleased. At follow up 37 of 39 (95%) of patients in group A had no pain. In group B 35 of 53 had no pain (66%). This is a statistically significant difference when analysed with Fisher’s exact test (p< 0.05).

Discussion: This study shows that an excessively open acetabular cup may contribute to persisting pain and patient dissatisfaction. This may be a result of excessive eccentric wear and metal ion deposition, and may lead to early failure of the prosthesis.

Introduction: Traditionally, hip resurfacing has been performed in younger patients. We compared the early results of a single surgeon series of ASR resurfacings performed in male patients in this age group with men over 60 years old.

Methods: 114 consecutive procedures were performed in male patients. Group 1 consisted of 48 hips in 43 patients aged 60 years and over (average age 64.2, range 60 to 73). Group 2 consisted of 66 hips in 59 male patients aged below 60 years (average age 50.4, range 31–59). Patients were followed up at a mean of 17.1 months in group 1 and 19.4 in group 2. BMI, ASA grade and proportion of Charnley walking grade A patients was similar.

Results: In group 1, average HHS improved from 56.4 to 98.6 and in group 2 from 54.2 to 96.7. Average UCLA activity score improved from 4.3 to 7.2 in group 1 and 4.1 to 7.7 in group 2. There has been 1 revision for neck fracture in group 1 (neck notched at time of primary procedure). There were no revisions in group 2. All of the patients in group 1, and 57 of 59 patients in group 2, give a high satisfaction rating. In group 1, one radiograph demonstrates lucency surrounding the ace-tabular component. This patient is asymptomatic with a HHS of 100 and a UCLA activity score of 10. There are areas of incomplete lucency around the components of a further 8 hips in group 1 and 10 in group 2. There has been no migration of components in either group.

Discussion: Functional outcome in patients over 60 years appears to be similar to younger patients. The early results are encouraging; we will continue to offer this procedure to active patients over 60. The areas of lucency on the radiographs will need careful follow-up to determine the long-term significance of these changes.