In a prospective study, 93 unselected consecutive uncemented hip arthroplasties were performed in 80 patients using the titanium-coated RM acetabular component and the CLS femoral component. The mean age of the patients at operation was 52 years (28 to 81). None were lost to follow-up. In the 23 patients who had died (26 hips) only one acetabular component had been revised. In the 57 living patients (67 hips), 13 such revisions had been performed. Of the 14 revisions, seven were for osteolysis, five for loosening and two for infection.

Survival analysis of this implant showed a total probability of survival of 83% (95% confidence interval 73 to 90), with all revisions as the endpoint, and a probability of 94% (95% confidence interval 87 to 98) with revision for aseptic loosening as the endpoint, indicating reliable long-term fixation of the titanium-coated RM acetabular component.

The best treatment for the active and lucid elderly patient with a displaced intracapsular fracture of the femoral neck is still controversial. Randomised controlled trials have shown that a primary total hip replacement is superior to internal fixation as regards the need for secondary surgery, hip function and health-related quality of life. Despite good results achieved with total hip replacement in this group, most orthopaedic surgeons still advocate hemiarthroplasty for this injury. We studied 120 patients with a mean age of 81 years (70 to 90) with an acute displaced intracapsular fracture of the femoral neck. They were randomly allocated to be treated with either a bipolar hemiarthroplasty or total hip replacement. Outcome measurements included peri-operative data, general and hip-specific complications, hip function and health-related quality of life. The patients were reviewed at four and 12 months.

The duration of surgery was longer in the total hip replacement group (102 minutes (70 to 151)) versus 78 minutes (43 to 131) (p < 0.001), and the intra-operative blood loss was increased 460 ml (100 to 1100) versus 320 ml (50 to 850) (p < 0.001), but there were no differences between the groups regarding any complications or mortality. There were no dislocations in either group. Hip function measured by the Harris hip score was significantly better in the total hip replacement group at both follow-up periods (p = 0.011 and p < 0.001, respectively). The health-related quality of life measure was in favour of the total hip replacement group but did not reach statistical significance (p = 0.818 at four months and p = 0.636 at 12 months).

These results indicate that a total hip replacement provides better function than a bipolar hemiarthroplasty as soon as one year post-operatively, without increasing the complication rate. We recommend total hip replacement as the primary treatment for this group of patients.

We have investigated whether control of balance is improved during stance and gait and sit-to-stand tasks after unilateral total hip replacement undertaken for osteoarthritis of the hip.

We examined 25 patients with a mean age of 67 years (sd 6.2) before and at four and 12 months after surgery and compared the findings with those of 50 healthy age-matched control subjects. For all tasks, balance was quantified using angular measurements of movement of the trunk.

Before surgery, control of balance during gait and sit-to-stand tasks was abnormal in patients with severe osteoarthritis of the hip, while balance during stance was similar to that of the healthy control group. After total hip replacement, there was a progressive improvement at four and 12 months for most gait and sit-to-stand tasks and in the time needed to complete them. By 12 months, the values approached those of the control group. However, trunk pitch (forwards-backwards) and roll (side-to-side) velocities were less stable (greater than the control) when walking over barriers as was roll for the sit-to-stand task, indicative of a residual deficit of balance.

Our data suggest that patients with symptomatic osteoarthritis of the hip have marked deficits of balance in gait tasks, which may explain the increased risk of falling which has been reported in some epidemiological studies. However, total hip replacement may help these patients to regain almost normal control of balance for some gait tasks, as we found in this study. Despite the improvement in most components of balance, however, the deficit in the control of trunk velocity during gait suggests that a cautious follow-up is required after total hip replacement regarding the risk of a fall, especially in the elderly.