Does use of a "rim cutter" improve quality of cementation of the acetabular component of cemented exeter total hip arthroplasty?

Minimum 5 year follow-up of clinical and radiographic results of cemented acetabular components with an interface bioactive bone cement technique in primary cemented total hip arthroplasty

INTRODUCTION

A well-fixed cement-bone interface is a crucial factor for acetabular and femoral components in cemented total hip arthroplasty (THA). The aim of the present study was to evaluate the middle-term clinical and radiological results of fixing the acetabular component with an interface bioactive bone cement (IBBC) technique in primary cemented THA.

MATERIALS AND METHODS

We undertook a retrospective review was undertaken of 193 primary cemented THAs in 174 patients using acetabular components cemented with an IBBC technique and followed for a minimum of 5 years (mean 8.3 years; range 5-17 years). Baseline data, clinical and radiological outcomes were evaluated.

RESULTS

Japanese Orthopedic Association hip score and modified Harris hip scores demonstrated significant clinical improvement in all patients (p < 0.001). Radiolucent lines were detected in 15 hips (7.8%) at the first year and 24 hips (12.4%) at the final post-operative follow-up. The Kaplan-Meier survivorship with radiographic loosening as the end point was 97.8% [95% confidence interval (CI) 95.2-100]. With revision of the acetabular component for aseptic loosening as the end point, component survival was 99.0% (95% CI 97.5-100). With revision of the acetabular component for any reason as the end point, component survival was 97.0% (95% CI 93.9-100).

CONCLUSIONS

Clinical and radiological results of the acetabular component with the IBBC technique in primary cemented THA were excellent.

Cemented versus uncemented femoral component total hip arthroplasty in elderly patients with primary osteoporosis: retrospective analysis with 5-year follow-up

Objective

To compare medium-term clinical and radiological outcomes of primary unilateral uncemented (UN) or cemented (CE) femoral component total hip arthroplasty (THA) in elderly patients with osteoporosis.

Methods

Consecutive patients with osteoporosis who underwent primary unilateral UN or CE THAs at our institution from 2006 to 2013 were retrospectively reviewed. All consecutive procedures were managed by high-volume surgeons, using UN or CE THA approaches. Follow-up assessments occurred at 1, 3, 6, 9, and 12 months postoperatively, and yearly thereafter. Patient-related functional outcomes were assessed using the Harris Hip Score (HHS). Primary and secondary endpoints were early revision (<5 years) and functional outcome.

Results

In total, 496 primary unilateral THAs (CE, n = 184; UN, n = 182) were assessed with a median follow-up period of 75 months (range, 65–86 months). From 3 months after surgery to the final follow-up, HHS was consistently superior in the CE group. Respective prosthetic loosening rates in the UN and CE groups were 26.4% and 16.8% at a minimum of 5 years. There was a significant difference in rate of early revision (7.6% CE vs. 14.8% UN).

Conclusion

Compared with UN THA, CE THA exhibits a superior outcome in elderly patients with primary osteoporosis.

The Rim Cutter does not show an advantage over modern cementing techniques: a five-year radiological and clinical follow-up of the Rim Cutter used with flanged acetabular components

AIMS

We report the incidence of radiolucent lines (RLLs) using two flanged acetabular components at total hip arthroplasty (THA) and the effect of the Rim Cutter.

PATIENTS AND METHODS

We performed a retrospective review of 300 hips in 292 patients who underwent primary cemented THA. A contemporary flanged acetabular component was used with (group 1) and without (group 2) the use of the Rim Cutter and the Rimfit acetabular component was used with the Rim Cutter (group 3). RLLs and clinical outcomes were evaluated immediately post-operatively and at five years post-operatively.

RESULTS

There was no significant difference in the incidence of RLLs on the immediate post-operative radiographs (p = 0.241) or at five years post-operatively (p = 0.463). RLLs were seen on the immediate post-operative radiograph in 2% of hips in group 1, in 5% in group 2 and in 7% in group 3. Five years post-operatively, there were RLLs in 42% of hips in group 1, 41% in group 2 and in 49% in group 3. In the vast majority of hips, in each group, the RLL was present in DeLee and Charnley zone 1 only (86%, 83%, 67% respectively). Oxford and Harris Hip scores improved significantly in all groups. There was no significant difference in these scores or in the change in scores between the groups, with follow-up.

CONCLUSION

Despite the Rim Cutter showing promising results in early laboratory and clinical studies, this analysis of the radiological and clinical outcome five years post-operatively does not show any advantage over and above modern cementing techniques in combination with a well performing cemented acetabular component. For this reason, we no longer use the Rim Cutter in routine primary THA. Cite this article: Bone Joint J 2017;99-B:1450-7.

The use of a "rim cutter" device and a flanged cup for improving the mantle of the acetabular component of a cemented Exeter total hip arthroplasty

A retrospective study was performed to evaluate the cement mantle in two groups of patients treated with the acetabular components of cemented Exeter total hip arthroplasties (THAs). Two groups of 20 patients were compared: Group 1 received non-flanged acetabular cemented cups (Contemporary, Stryker) and Group 2 received flanged acetabular cemented cups (X3 Rim Fit, Stryker). Cups in Group 2 were implanted after using a rim cutter device. Group 2 showed better penetration of cement in zone 1 (10.76 mm compared with 2.93 mm; p = 0.008) and a thicker cement mantle in zone 1 (3.57 mm compared with 2.89 mm; p = 0.04). More cups in Group 2 had a cement mantle thickness less than 3 mm (30 % in Group 1 compared with 70 % in Group 2; p = 0.0039). No other radiological differences were observed. These results favor the use of a rim cutter device and flanged cup to improve the cement mantle for the acetabular components of cemented Exeter THAs. However, the improvements were less than expected. In view of the results of previous studies, further research is therefore needed to assess the value of this approach in improving the acetabular cement mantle.

Progressive radiolucent lines following the implantation of the cemented Rimfit acetabular component in total hip arthroplasty using the rimcutter technique: cause for concern?

AIMS

The highly cross-linked polyethylene Exeter RimFit flanged cemented acetabular component was introduced in the United Kingdom in 2010. This study aimed to examine the rates of emergence of radiolucent lines observed when the Rimfit acetabular component was implanted at total hip arthroplasty (THA) using two different techniques: firstly, the 'rimcutter' technique in which the flange sits on a pre-prepared acetabular rim; and secondly, the 'trimmed flange' technique in which the flange is trimmed and the acetabular component is seated inside the rim of the acetabulum.

PATIENTS AND METHODS

The radiographs of 150 THAs (75 'rimcutter', 75 'trimmed flange') involving this component were evaluated to assess for radiolucencies at the cement/bone interface by three observers.

RESULTS

Rimfit acetabular components implanted using the rimcutter technique had significantly higher rates of radiolucency than those introduced using the 'trimmed flange' technique one year post-operatively (one zone: 63/75 (84%) vs 17/75 (23%); two zones 42/75 (56%) vs 0/75 (0%); all three zones 17/75 (23%) vs 0/75 (0%):(all p < 0.001).

CONCLUSION

On the basis of these findings, we have stopped using the 'rimcutter' technique when implanting the Rimfit acetabular component and have reverted to the 'trimmed flange' technique.

TAKE HOME MESSAGE

Surgeons should be vigilant of the performance of the Rimfit acetabular component when used alongside the rim cutter device due to an observed higher rate of progressive radiolucencies with this combination of component / technique.

Total hip replacement and surface replacement for the treatment of pain and disability resulting from end-stage arthritis of the hip (review of technology appraisal guidance 2 and 44): systematic review and economic evaluation

BACKGROUND

Total hip replacement (THR) involves the replacement of a damaged hip joint with an artificial hip prosthesis. Resurfacing arthroplasty (RS) involves replacement of the joint surface of the femoral head with a metal surface covering.

OBJECTIVES

To undertake clinical effectiveness and cost-effectiveness analysis of different types of THR and RS for the treatment of pain and disability in people with end-stage arthritis of the hip, in particular to compare the clinical effectiveness and cost-effectiveness of (1) different types of primary THR and RS for people in whom both procedures are suitable and (2) different types of primary THR for people who are not suitable for hip RS.

DATA SOURCES

Electronic databases including MEDLINE, EMBASE, The Cochrane Library, Current Controlled Trials and UK Clinical Research Network (UKCRN) Portfolio Database were searched in December 2012, with searches limited to publications from 2008 and sample sizes of ≥ 100 participants. Reference lists and websites of manufacturers and professional organisations were also screened.

REVIEW METHODS

Systematic reviews of the literature were undertaken to appraise the clinical effectiveness and cost-effectiveness of different types of THR and RS for people with end-stage arthritis of the hip. Included randomised controlled trials (RCTs) and systematic reviews were data extracted and risk of bias and methodological quality were independently assessed by two reviewers using the Cochrane Collaboration risk of bias tool and the Assessment of Multiple Systematic Reviews (AMSTAR) tool. A Markov multistate model was developed for the economic evaluation of the technologies. Sensitivity analyses stratified by sex and controlled for age were carried out to assess the robustness of the results.

RESULTS

A total of 2469 records were screened of which 37 were included, representing 16 RCTs and eight systematic reviews. The mean post-THR Harris Hip Score measured at different follow-up times (from 6 months to 10 years) did not differ between THR groups, including between cross-linked polyethylene and traditional polyethylene cup liners (pooled mean difference 2.29, 95% confidence interval -0.88 to 5.45). Five systematic reviews reported evidence on different types of THR (cemented vs. cementless cup fixation and implant articulation materials) but these reviews were inconclusive. Eleven cost-effectiveness studies were included; four provided relevant cost and utility data for the model. Thirty registry studies were included, with no studies reporting better implant survival for RS than for all types of THR. For all analyses, mean costs for RS were higher than those for THR and mean quality-adjusted life-years (QALYs) were lower. The incremental cost-effectiveness ratio for RS was dominated by THR, that is, THR was cheaper and more effective than RS (for a lifetime horizon in the base-case analysis, the incremental cost of RS was £11,284 and the incremental QALYs were -0.0879). For all age and sex groups RS remained clearly dominated by THR. Cost-effectiveness acceptability curves showed that, for all patients, THR was almost 100% cost-effective at any willingness-to-pay level. There were age and sex differences in the populations with different types of THR and variations in revision rates (from 1.6% to 3.5% at 9 years). For the base-case analysis, for all age and sex groups and a lifetime horizon, mean costs for category E (cemented components with a polyethylene-on-ceramic articulation) were slightly lower and mean QALYs for category E were slightly higher than those for all other THR categories in both deterministic and probabilistic analyses. Hence, category E dominated the other four categories. Sensitivity analysis using an age- and sex-adjusted log-normal model demonstrated that, over a lifetime horizon and at a willingness-to-pay threshold of £20,000 per QALY, categories A and E were equally likely (50%) to be cost-effective.

LIMITATIONS

A large proportion of the included studies were inconclusive because of poor reporting, missing data, inconsistent results and/or great uncertainty in the treatment effect estimates. This warrants cautious interpretation of the findings. The evidence on complications was scarce, which may be because of the absence or rarity of these events or because of under-reporting. The poor reporting meant that it was not possible to explore contextual factors that might have influenced study results and also reduced the applicability of the findings to routine clinical practice in the UK. The scope of the review was limited to evidence published in English in 2008 or later, which could be interpreted as a weakness; however, systematic reviews would provide summary evidence for studies published before 2008.

CONCLUSIONS

Compared with THR, revision rates for RS were higher, mean costs for RS were higher and mean QALYs gained were lower; RS was dominated by THR. Similar results were obtained in the deterministic and probabilistic analyses and for all age and sex groups THR was almost 100% cost-effective at any willingness-to-pay level. Revision rates for all types of THR were low. Category A THR (cemented components with a polyethylene-on-metal articulation) was more cost-effective for older age groups. However, across all age-sex groups combined, the mean cost for category E THR (cemented components with a polyethylene-on-ceramic articulation) was slightly lower and the mean QALYs gained were slightly higher. Category E therefore dominated the other four categories. Certain types of THR appeared to confer some benefit, including larger femoral head sizes, use of a cemented cup, use of a cross-linked polyethylene cup liner and a ceramic-on-ceramic as opposed to a metal-on-polyethylene articulation. Further RCTs with long-term follow-up are needed.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013003924.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Benefits of using modern cementing techniques in the acetabulum: the Rim Cutter

PURPOSE

To compare radiological records of 90 consecutive patients who underwent cemented total hip arthroplasty (THA) with or without use of the Rim Cutter to prepare the acetabulum.

METHODS

The acetabulum of 45 patients was prepared using the Rim Cutter, whereas the device was not used in the other 45 patients. Postoperative radiographs were evaluated using a digital templating system to measure (1) the positions of the operated hips with respect to the normal, contralateral hips (the centre of rotation of the socket, the height of the centre of rotation from the teardrop, and lateralisation of the centre of rotation from the teardrop) and (2) the uniformity and width of the cement mantle in the 3 DeLee Charnley acetabular zones, and the number of radiolucencies in these zones.

RESULTS

The study group showed improved radiological parameters and were closer to the anatomic centre of rotation both vertically (1.5 vs. 3.7 mm, p<0.001) and horizontally (1.8 vs. 4.4 mm, p<0.001) and had consistently thicker and more uniform cement mantles (p<0.001). There were 2 radiolucent lines in the control group but none in the study group.

CONCLUSION

The Rim Cutter resulted in more accurate placement of the centre of rotation of a cemented prosthetic socket, and produced a thicker, more congruent cement mantle with fewer radiolucent lines.

The Exeter Universal cemented femoral component at 15 to 17 years

The first 325 Exeter Universal stems (309 patients) implanted at the originating centre were inserted between March 1988 and February 1990 by a group of surgeons with differing experience. In this report we describe the clinical and radiological results at a mean of 15.7 years (14.7 to 17.3) after operation with no loss to follow-up. There were 97 patients (108 hips) with replacements still in situ and 31 (31 hips) who had undergone a further procedure. With an endpoint of revision for aseptic loosening, the survivorship at 17 years was 100% and 90.4% for the femoral and acetabular component, respectively. The mean Merle D’Aubigné and Postel scores at review were 5.4 (sd 0.97) for pain and 4.5 (sd 1.72) for function. The mean Oxford score was 38.4 (sd 9.8) (0 to 48 worst-to-best scale) and the mean combined Harris pain and function score was 73.2 (sd 16.9). Radiological review showed excellent preservation of bone stock in the proximal femur and no failures of the femoral component.