Clinical and radiographic outcomes of acetabular impaction grafting without cage reinforcement for revision hip replacement : a minimum ten-year follow-up study

Impaction bone grafting for reconstitution of bone stock in revision hip surgery has been used for nearly 30 years. We used this technique, in combination with a cemented acetabular component, in the acetabula of 304 hips in 292 patients revised for aseptic loosening between 1995 and 2001. The only additional supports used were stainless steel meshes placed against the medial wall or laterally around the acetabular rim to contain the graft. All Paprosky grades of defect were included. Clinical and radiographic outcomes were collected in surviving patients at a minimum of 10 years following the index operation. Mean follow-up was 12.4 years (SD 1.5; range 10.0-16.0). Kaplan-Meier survivorship with revision for aseptic loosening as the endpoint was 85.9% (95% CI 81.0 to 90.8%) at 13.5 years. Clinical scores for pain relief remained satisfactory, and there was no difference in clinical scores between cups that appeared stable and those that appeared loose radiographically.

Femoral impaction grafting in revision total hip arthroplasty

Between 1987 and 1999, 540 revision total hip replacements in 487 patients were performed at our institution with the femoral impaction grafting technique with a cemented femoral stem. All patients were prospectively followed for 2-15years post-operatively with no loss to follow-up. 494 hips remained successfully in situ at an average 6.7years. The ten year survival rate was 98.0% (95% CI 96.2 to 99.8) with aseptic loosening as the endpoint and 84.2% (95% CI 78.5 to 89.9) for re-operation for any reason. Indication for surgery and the use of any kind of reinforcement significantly influenced outcome (p<0.001). This is the largest known series of revision THR with femoral impaction grafting and the results support continued use of this technique.

The Exeter Hip. 40 Years of Innovation in Total Hip Arthroplasty

* Propoerties and use of acrylic cement * Design and biomechaniscs of a cemented hip replacement * The science of loosening, lysis and wear * Preparation of patients for surgery * Potential complications and their avoidance * Modern primary surgical techniques and new developments * Complex primary hip replacement and specialist techniques * Outcomes of cemented hip replacement * Principles of revision hip replacement * Basic science of bone grafting in revision surgery * Femoral acetabular impaction bone grafting techniques * Results of revision with bone graft and cement

Re-cementing in revision total hip replacement

Removal of well-fixed cement at revision surgery risks bone loss, cortical perforation and fracture, is time-consuming, technically demanding and carries increased risks for the patient. The cement-in-cement technique avoids these problems and when used appropriately has given favourable results at our centre when used on both the femoral and acetabular sides of the articulation. A modified technique has also been used in selected cases of infection and peri-prosthetic fracture. This chapter highlights the results to date and the operative techniques employed. It is essential to recognise that this technique relies fundamentally on the presence of a well-fixed cement mantle, and it is imperative that the criteria laid out are adhered to in order to achieve success. If there is loosening or lysis on the femoral side extending distal to the lesser trochanter or around more than just the periphery of the acetabular cement mantle, then alternative revision techniques should be employed.

Indications for early hip revision surgery in the UK : A re-analysis of NJR data

This study determined the rate and indication for revision between cemented, uncemented, hybrid and resurfacing groups from NJR (6 th edition) data. Data validity was determined by interrogating for episodes of misclassification. We identified 6,034 (2.7%) misclassified episodes, containing 97 (4.3%) revisions. Kaplan-Meier revision rates at 3 years were 0.9% cemented, 1.9% for uncemented, 1.2% for hybrids and 3.0% for resurfacings (significant difference across all groups, p<0.001, with identical pattern in patients <55 years). Regression analysis indicated both prosthesis group and age significantly influenced failure (p<0.001). Revision for pain, aseptic loosening, and malalignment were highest in uncemented and resurfacing arthroplasty. Revision for dislocation was highest in uncemented hips (significant difference between groups, p<0.001). Feedback to the NJR on data misclassification has been made for future analysis. © 2012 Wichtig Editore.

Revision total hip replacement using the cement-in-cement technique for the acetabular component : technique and results for 60 hips

The technique of femoral cement-in-cement revision is well established, but there are no previous series reporting its use on the acetabular side at the time of revision total hip arthroplasty. We describe the surgical technique and report the outcome of 60 consecutive cement-in-cement revisions of the acetabular component at a mean follow-up of 8.5 years (range 5-12 years). All had a radiologically and clinically well fixed acetabular cement mantle at the time of revision. 29 patients died. No case was lost to follow-up. The 2 most common indications for acetabular revision were recurrent dislocation (77%) and to compliment a femoral revision (20%). There were 2 cases of aseptic cup loosening (3.3%) requiring re-revision. No other hip was clinically or radiologically loose (96.7%) at latest follow-up. One case was re-revised for infection, 4 for recurrent dislocation and 1 for disarticulation of a constrained component. At 5 years, the Kaplan-Meier survival rate was 100% for aseptic loosening and 92.2% (95% CI; 84.8-99.6%) with revision for all causes as the endpoint. These results support the use of the cement-in-cement revision technique in appropriate cases on the acetabular side. Theoretical advantages include preservation of bone stock, reduced operating time, reduced risk of complications and durable fixation.

Aetiology of Hip dislocation

Written by the surgeons of the Exeter Hip Team and their colleagues from around the world, this book describes 40 years of innovation and development with cemented hip replacement. Topics covered include the basic science behind successful cemented hip replacement, modern surgical techniques and recent advances. There is also extensive coverage of the revision techniques developed at Exeter and elsewhere, focussing on femoral and acetabular impaction grafting. Each chapter is a self-contained article with an emphasis, where appropriate, on practical techniques and surgical tips, supported by line drawings and intra-operative photographs.

The use of cement in hip arthroplasty

Written by the surgeons of the Exeter Hip Team and their colleagues from around the world, this book describes 40 years of innovation and development with cemented hip replacement. Topics covered include the basic science behind successful cemented hip replacement, modern surgical techniques and recent advances. There is also extensive coverage of the revision techniques developed at Exeter and elsewhere, focussing on femoral and acetabular impaction grafting. Each chapter is a self-contained article with an emphasis, where appropriate, on practical techniques and surgical tips, supported by line drawings and intra-operative photographs.

Is there a need for routine follow-up after primary total hip arthroplasty?

Background: The objective of routine outpatient assessment of well functioning patients after primary total hip arthroplasty (THA) is to detect asymptomatic failure of prostheses to guide recommendations for early intervention. We have observed that the revision of THAs in asymptomatic patients is highly uncommon. We therefore question the need for routine follow-up of patients after THA. Methods: A prospective analysis of an orthopaedic database identified 158 patients who received 177 revision THAs over a 4 year period. A retrospective chart review was conducted. Patient demographics, primary and revision surgery parameters and follow-up information was recorded and cross referenced with AOA NJRR data. Results: 110 THAs in 104 patients (average age 70.4 (SD 9.8 years). There were 70 (63.6%) total, 13 (11.8%) femoral and 27 (24.5%) acetabular revisions. The indications for revision were aseptic loosening (70%), dislocation (8.2%), peri-prosthetic fracture (7.3%), osteolysis (6.4%) and infection (4.5%). Only 4 (3.6%) were asymptomatic revisions. A mean of 5.3 (SD 5.2 and 1.9 (SD 5.3 follow-up appointments were required before revision in patients with and without symptoms, respectively. The average time from the primary to revision surgery was 11.8 (SD 7.23) years. Conclusions: We conclude that patients with prostheses with excellent long term clinical results as validated by Joint Registries, routine follow-up of asymptomatic THA should be questioned and requires further investigation. Based on the work of this study, the current practice of routine follow-up of asymptomatic THA may be excessively costly and unnecessary and a less resource-intensive review method may be more appropriate.

The concentric all-polyethylene Exeter acetabular component in primary total hip replacement

We report the long term outcome of the flangeless, cemented all polyethylene Exeter cup at a mean of 14.6 years (range 10-17) after operation. Of the 263 hips in 243 patients, 122 hips are still in situ, 112 patients (119 hips) have died, eighteen hips were revised, and three patients (four hips) had moved abroad and were lost to follow-up (1.5%). Radiographs demonstrated two sockets had migrated and six more had radiolucent lines in all three zones. The Kaplan Meier survivorship at 15 years with endpoint revision for all causes is 89.9% (95% CI 84.6 to 95.2%) and for aseptic cup loosening or lysis 91.7% (CI 86.6 to 96.8%). In 210 hips with a diagnosis of primary osteoarthritis survivorship for all causes is 93.2% (95% CI 88.1 to 98.3%), and for aseptic cup loosening 95.0% (CI 90.3 to 99.7%). The cemented all polyethylene Exeter cup has an excellent long-term survivorship.

Acetabular impaction grafting in total hip replacement

Background and purpose: Acetabular impaction grafting has been shown to have excellent results, but concerns regarding its suitability for larger defects have been highlighted. We report the use of this technique in a large cohort of patients with the aim of better understanding the limitations of the technique. Methods: We investigated a consecutive group of 339 cases of impaction grafting of the cup with morcellised impacted allograft bone for survivorship and mechanisms for early failure. Results: Kaplan Meier survival was 89.1% (95% CI 83.2 to 95.0%) at 5.8 years for revision for any reason, and 91.6% (95% CI 85.9 to 97.3%) for revision for aseptic loosening of the cup. Of the 15 cases revised for aseptic cup loosening, nine were large rim mesh reconstructions, two were fractured Kerboull-Postel plates, two were migrating cages, one medial wall mesh failure and one impaction alone failed. Interpretation: In our series, results were disappointing where a large rim mesh or significant reconstruction was required. In light of these results, our technique has changed in that we now use predominantly larger chips of purely cancellous bone, 8-10 mm3 in size, to fill the cavity and larger diameter cups to better fill the mouth of the reconstructed acetabulum. In addition we now make greater use of i) implants made of a highly porous in-growth surface to constrain allograft chips and ii) bulk allografts combined with cages and morcellised chips in cases with very large segmental and cavitary defects.

Evaluation of the cost-effectiveness of strategies claiming to reduce the risk of surgical site infections following primary total hip arthroplasty

Background Total hip arthroplasty (THA) is a commonly performed procedure and numbers are increasing with ageing populations. One of the most serious complications in THA are surgical site infections (SSIs), caused by pathogens entering the wound during the procedure. SSIs are associated with a substantial burden for health services, increased mortality and reduced functional outcomes in patients. Numerous approaches to preventing these infections exist but there is no gold standard in practice and the cost-effectiveness of alternate strategies is largely unknown. Objectives The aim of this project was to evaluate the cost-effectiveness of strategies claiming to reduce deep surgical site infections following total hip arthroplasty in Australia. The objectives were: 1. Identification of competing strategies or combinations of strategies that are clinically relevant to the control of SSI related to hip arthroplasty 2. Evidence synthesis and pooling of results to assess the volume and quality of evidence claiming to reduce the risk of SSI following total hip arthroplasty 3. Construction of an economic decision model incorporating cost and health outcomes for each of the identified strategies 4. Quantification of the effect of uncertainty in the model 5. Assessment of the value of perfect information among model parameters to inform future data collection Methods The literature relating to SSI in THA was reviewed, in particular to establish definitions of these concepts, understand mechanisms of aetiology and microbiology, risk factors, diagnosis and consequences as well as to give an overview of existing infection prevention measures. Published economic evaluations on this topic were also reviewed and limitations for Australian decision-makers identified. A Markov state-transition model was developed for the Australian context and subsequently validated by clinicians. The model was designed to capture key events related to deep SSI occurring within the first 12 months following primary THA. Relevant infection prevention measures were selected by reviewing clinical guideline recommendations combined with expert elicitation. Strategies selected for evaluation were the routine use of pre-operative antibiotic prophylaxis (AP) versus no use of antibiotic prophylaxis (No AP) or in combination with antibiotic-impregnated cement (AP & ABC) or laminar air operating rooms (AP & LOR). The best available evidence for clinical effect size and utility parameters was harvested from the medical literature using reproducible methods. Queensland hospital data were extracted to inform patients’ transitions between model health states and related costs captured in assigned treatment codes. Costs related to infection prevention were derived from reliable hospital records and expert opinion. Uncertainty of model input parameters was explored in probabilistic sensitivity analyses and scenario analyses and the value of perfect information was estimated. Results The cost-effectiveness analysis was performed from a health services perspective using a hypothetical cohort of 30,000 THA patients aged 65 years. The baseline rate of deep SSI was 0.96% within one year of a primary THA. The routine use of antibiotic prophylaxis (AP) was highly cost-effective and resulted in cost savings of over $1.6m whilst generating an extra 163 QALYs (without consideration of uncertainty). Deterministic and probabilistic analysis (considering uncertainty) identified antibiotic prophylaxis combined with antibiotic-impregnated cement (AP & ABC) to be the most cost-effective strategy. Using AP & ABC generated the highest net monetary benefit (NMB) and an incremental $3.1m NMB compared to only using antibiotic prophylaxis. There was a very low error probability that this strategy might not have the largest NMB (<5%). Not using antibiotic prophylaxis (No AP) or using both antibiotic prophylaxis combined with laminar air operating rooms (AP & LOR) resulted in worse health outcomes and higher costs. Sensitivity analyses showed that the model was sensitive to the initial cohort starting age and the additional costs of ABC but the best strategy did not change, even for extreme values. The cost-effectiveness improved for a higher proportion of cemented primary THAs and higher baseline rates of deep SSI. The value of perfect information indicated that no additional research is required to support the model conclusions. Conclusions Preventing deep SSI with antibiotic prophylaxis and antibiotic-impregnated cement has shown to improve health outcomes among hospitalised patients, save lives and enhance resource allocation. By implementing a more beneficial infection control strategy, scarce health care resources can be used more efficiently to the benefit of all members of society. The results of this project provide Australian policy makers with key information about how to efficiently manage risks of infection in THA.