THA for a Fractured Femoral Neck: Comparing the Revision and Dislocation Rates of Standard-head, Large-head, Dual-mobility, and Constrained Liners

No Difference in Revision Rates or Patient-Reported Outcome Measures Between Surgical Approaches for Total Hip Arthroplasty Performed for Femoral Neck Fracture: An Analysis of 5,025 Primary Total Hip Arthroplasties From the New Zealand Joint Registry

BACKGROUND

Total hip arthroplasty (THA) for femoral neck fracture (FNF) can be performed through different surgical approaches. This study compared the revision rates and patient-reported outcome measures by surgical approach.

METHODS

Data from the New Zealand Joint Registry were analyzed for patients undergoing primary THA for FNF from January 2000 to December 2021. A total of 5,025 THAs were performed for FNF; the lateral approach was used in 2,499 (49.7%), the posterior in 2,255 (44.9%), and the anterior in 271 (4.3%). The primary outcome measure was the all-cause revision rate. Secondary outcome measures included revision rates for: dislocation, aseptic femoral component loosening, periprosthetic fracture, and infection. Oxford Hip Scores (OHS) were also collected. Age, sex, body mass index, American Society of Anesthesiologists score, femoral head size, dual mobility use, femoral fixation, and surgeon experience were assessed as potential confounding variables.

RESULTS

There was no difference in the revision rates between lateral and posterior (P = .156), lateral and anterior (P = .680), or posterior and anterior (P = .714) approaches. There was no difference in the reasons for revision between the lateral and posterior approaches or 6-month OHS (P = .712). There was insufficient data to compare the anterior approach.

CONCLUSIONS

There is no difference in the overall revision rates, reasons for revision, or OHS between the lateral and posterior surgical approaches for THA performed for FNF. Insufficient data on the anterior approach is available for an accurate comparison.

LEVEL OF EVIDENCE

Level III.

What is the most appropriate comparator group to use in assessing the performance of primary total hip prostheses within the community?

BACKGROUND

There are variations in the performance of individual prostheses used in hip replacements. Some of which have unexpectedly higher revision rates - outliers. The Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) has established a standardised multi-stage approach for identifying these devices. This is done by comparing the revision rates of individual prostheses to all other prostheses in class, with the exception of large head metal-on-metal (LHMoM) prostheses. However, improvements in device design and performance over time have required a need to reconsider the comparator group. This study aimed to identify a more specific comparator to better reflect contemporary surgical practice.

METHODS

The time to first revision was estimated on the data of 413,417 primary total conventional hip replacements undertaken for osteoarthritis (OA) from 01 January 2003 to 31 December 2019. Survivorship analyses with stepwise exclusions were undertaken. The first exclusion was LHMoM, followed by other non-modern bearing surfaces (defined as all the bearing couples except metal or ceramic heads on cross-linked polyethylene and mixed ceramic-on-ceramic), and then devices with modular neck-stem design or used for specific purposes (incl. constrained, dual-mobility, and head size <28 mm). Lastly, all remaining prostheses previously identified as having a higher than anticipated rate of revision (HTARR) were also excluded.

RESULTS

These exclusions progressively reduced the cumulative percent revision (CPR) rate. The final comparator, which only includes satisfactory-performed prostheses of contemporary design and use, has a 10-year CPR of 4.30% (95% CI, 4.2-4.41) which is lower than 4.93% (95% CI, 4.84-5.02) for the current comparator used by the AOANJRR (all prostheses excluding LHMOM). Over the study period, 13 additional components were identified utilising the modified comparator.

CONCLUSIONS

The calculation of the comparator revision rate should be re-evaluated to include only modern prosthesis constructs to ensure that poorly performing prostheses are identified early.

The True Dislocation Incidence following Elective Total Hip Replacement in Sweden: How Does It Relate to the Revision Rate?

(1) Background: The true dislocation incidence following THA is difficult to ascertain in population-based cohorts. In this study, we explored the cumulative dislocation incidence (CDI), the relationship between the incidence of dislocation and revision surgery, patient- and surgery-related factors in patients dislocating once or multiple times, and differences between patients being revised for dislocation or not. (2) Methods: We designed an observational longitudinal cohort study linking registers. All patients with a full dataset who underwent an elective unilateral THA between 1999 and 2014 were included. The CDI and the time from the index THA to the first dislocation or to revision were estimated using the Kaplan-Meier (KM) method, giving cumulative dislocation and revision incidences at different time points. (3) Results: 136,810 patients undergoing elective unilateral THA were available for the analysis. The 30-day CDI was estimated at 0.9% (0.9-1.0). The revision rate for dislocation throughout the study period remained much lower. A total of 51.2% (CI 49.6-52.8) suffered a further dislocation within 1 year. Only 10.9% of the patients with a dislocation within the first year postoperatively underwent a revision for dislocation. (4) Discussion: The CDI after elective THA was expectedly considerably higher than the revision incidence. Further studies investigating differences between single and multiple dislocators and the criteria by which patients are offered revision surgery following dislocation are urgently needed.

Nutritional Risk Screening 2002 predicts surgical outcomes in 1532 patients undergoing total joint arthroplasty: A retrospective cohort study

BACKGROUND

Limited information exists about the predictive effect of Nutritional Risk Screening (NRS) 2002 on orthopedic surgery. The aim of the present study is to explore the role of NRS 2002 in postoperative complications and resource utilization in patients with total joint arthroplasty (TJA).

METHODS

We retrospectively collected the demographics and surgical results of nearly 2000 TJA patients admitted from 2016 to 2020 and assessed the differences in short- and long-term complications and resource utilization parameters. Multivariate linear, logistic regression, and subgroup analysis were subsequently used to control for potential confounders. Survival analysis was performed to further verify the cumulative incidence of postoperative complications.

RESULTS

We identified 1532 patients receiving TJA, 8.7% of which were at nutrition risk (NRS 2002 score ≥3 out of 7). Preoperative nutrition risk was associated with an increased risk of systemic complications, incisional complications, surgical site infection (SSI), incisional SSI, periprosthetic joint infection, dislocation, and periprosthetic fracture after TJA (odds ratio [OR], 3.62-31.99; all P < 0.05). Preoperative nutrition risk was further associated with an increased risk of cardiac complications, respiratory complications, urinary complications, and arthroplasty-related reoperation (OR, 3.16-12.29; all P < 0.01). Moreover, preoperative nutrition risk was associated with increased costs and length of stay, and increased risk of unplanned intensive care unit admission, arthroplasty-related readmission, infection-related readmission, and SSI-related readmission.

CONCLUSIONS

NRS 2002 is associated with an elevated risk of postoperative complications and increased resource utilization, following TJA. Thus, routine screening is recommended to identify nutrition risk statuses of patients undergoing elective TJA.

Do Dual-mobility Cups Reduce Revision Risk in Femoral Neck Fractures Compared With Conventional THA Designs? An International Meta-analysis of Arthroplasty Registries

BACKGROUND

Dual-mobility cups in THA were designed to reduce prosthesis instability and the subsequent risk of revision surgery in high-risk patients, such as those with hip fractures. However, there are limited data from clinical studies reporting a revision benefit of dual-mobility over conventional THA. Collaboration between anthroplasty registries provides an opportunity to describe international practice variation and compare between-country, all-cause revision rates for dual-mobility and conventional THA.

QUESTIONS/PURPOSES

We summarized observational data from multiple arthroplasty registries for patients receiving either a dual-mobility or conventional THA to ask: (1) Is dual-mobility use associated with a difference in risk of all-cause revision surgery compared with conventional THA? (2) Are there specific patient characteristics associated with dual-mobility use in the hip fracture population? (3) Has the use of dual-mobility constructs changed over time in patients receiving a THA for hip fracture?

METHODS

Six member registries of the International Society of Arthroplasty Registries (from Australia, Denmark, Sweden, the Netherlands, the United Kingdom, and the United States) provided custom aggregate data reports stratified by acetabular cup type (dual-mobility or conventional THA) in primary THA for hip fracture between January 1, 2002, and December 31, 2019; surgical approach; and patient demographic data (sex, mean age, American Society of Anesthesiologists class, and BMI). The cumulative percent revision and mortality were calculated for each registry. To determine a global hazard ratio of all-cause revision for dual-mobility compared with conventional THA designs, we used a pseudoindividual patient data approach to pool Kaplan-Meier prosthesis revision data from each registry and perform a meta-analysis. The pseudoindividual patient data approach is a validated technique for meta-analysis of aggregate time-to-event survival data, such as revision surgery, from multiple sources. Data were available for 15,024 dual-mobility THAs and 97,200 conventional THAs performed for hip fractures during the study period.

RESULTS

After pooling of complete Kaplan-Meier survival data from all six registries, the cumulative percent revision for conventional THA was 4.3% (95% confidence interval [CI] 4.2% to 4.5%) and 4.7% (95% CI 4.3% to 5.3%) for dual-mobility THA at 5 years. We did not demonstrate a lower risk of all-cause revision for patients receiving dual-mobility over conventional THA designs for hip fracture in the meta-analysis once between-registry differences were adjusted for (HR 0.96 [95% CI 0.86 to 1.06]). A lower proportion of dual-mobility procedures were revised for dislocation than conventional THAs (0.9% versus 1.4%) but a higher proportion were revised for infection (1.2% versus 0.8%). In most registries, a greater proportion of dual-mobility THA patients were older, had more comorbidities, and underwent a posterior approach compared with conventional THA (p < 0.001). The proportion of dual-mobility THA used to treat hip fractures increased in each registry over time and constituted 21% (2438 of 11,874) of all THA procedures in 2019.

CONCLUSION

The proportion of dual-mobility THAs in patients with hip fractures increased over time, but there was large variation in use across countries represented here. Dual-mobility cups were not associated with a reduction in the overall risk of revision surgery in patients with hip fractures. A randomized controlled trial powered to detect the incidence of dislocation and subsequent revision surgery is required to clarify the efficacy of dual-mobility cups to treat hip fractures.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The top fifty most influential articles on hip fractures

PURPOSE

Hip fractures are one of the most common disabling fractures in elderly people and peri-operative management has advanced considerably over the past decades. The purpose of this study was to evaluate the change of scientific focus by creating a top 50 list of the most influential papers on this topic.

METHODS

The Clarivate Web of Science Search was used to identify the most cited articles. The used search phrase was [(hip OR pertrochanteric OR (femoral neck)) AND fracture AND (surgery OR treatment)]. The number of citations, citation density, study type, study design, published year, fracture type, country, evidence level and published journal were recorded.

RESULTS

The top 50 articles were published between 1973 and 2014 and cited between 88 and 496 times. The mean citation density increased noticeably after the year 2000, representing the knowledge gain of the last 20 years. The topics surgical treatment (n = 19), risk factor assessment (n = 19), perioperative hemodynamic management (n = 7), additional treatment (n = 4) and general reviews (n = 1) were covered. Twenty-five articles were published from institutions in Europe, 24 from institutions in North America and one from an institution in Asia.

CONCLUSION

While studies about surgical treatment options and risk factor assessment have been historically important, there was a rise of articles about additional treatment options for osteoporosis and the optimal postoperative care after the year 2005. The presented lists and map of citation classics give an overview of the most influential studies on hip fractures.

Dual mobility versus conventional total hip arthroplasty in femoral neck fractures (DISTINCT): protocol for a registry-nested, open-label, cluster-randomised crossover trial

INTRODUCTION

Hip fractures treated with total hip arthroplasty (THA) are at high risk of prosthesis instability, and dislocation is the most common indication for revision surgery. This study aims to determine whether dual mobility THA implants reduce the risk of dislocation compared with conventional THA in patients with hip fracture suitable to be treated with THA.

METHODS AND ANALYSIS

This is a cluster-randomised, crossover, open-label trial nested within the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). The clusters will comprise hospitals that perform at least 12 THAs for hip fracture per annum. All adults age ≥50 years who meet the Australian and New Zealand Hip Fracture Registry guidelines for THA will be included. The intervention will be dual mobility THA and the comparator will be conventional THA. Each hospital will be allocated to two consecutive periods, one of dual mobility THA and the other of conventional THA in random order, aiming for an average of 16 patients eligible for the primary analysis per group (32 total per site), allowing different recruitment totals between sites. Data will be collected through the AOANJRR and linked with patient-level discharge data acquired through government agencies. The primary outcome is dislocation within 1 year. Secondary outcomes include revision surgery for dislocation and all-cause, complications and mortality at 1, 2 and 5 years. If dual mobility THA is found to be superior, a cost-effectiveness analysis will be conducted. The study will aim to recruit 1536 patients from at least 48 hospitals over 3 years.

ETHICS AND DISSEMINATION

Ethics approval has been granted (Sydney Local Health District - Royal Prince Alfred Hospital Zone (approval X20-0162 and 2020/ETH00680) and site-specific approvals). Participant recruitment is via an opt-out consent process as both treatments are considered accepted, standard practice. The trial is endorsed by the Australia and New Zealand Musculoskeletal Clinical Trials Network.

TRIAL REGISTRATION NUMBER

ACTRN12621000069853.

Is the Revision Rate for Femoral Neck Fracture Lower for Total Hip Arthroplasty Than for Hemiarthroplasty?: A Comparison of Registry Data for Contemporary Surgical Options

BACKGROUND

When arthroplasty is indicated for a femoral neck fracture (FNF), it is unclear whether total hip arthroplasty (THA) or hemiarthroplasty (HA) is best. This study compares data from the Australian Orthopaedic Association National Joint Replacement Registry using contemporary surgical options.

METHODS

Patients from 60 to 85 years old who were treated with arthroplasty for FNF, between September 1999 and December 2019, were included if the femoral stems were cemented. Only THAs with femoral heads of ≥36 mm or dual-mobility articulations were included. Patients who had monoblock HA were excluded. Rates of revision for all aseptic failures and dislocation were compared. Competing risks of revision and death were considered using the cumulative incidence function. Subdistribution hazard ratios (HRs) for revision or death from a Fine-Gray regression model were used to compare THA and HA. Interactions of procedure with age group and sex were considered. Secondary analysis adjusting for body mass index (BMI) and American Society of Anesthesiologists (ASA) classification was also considered.

RESULTS

There were 4,551 THA and 29,714 HA procedures included. The rate of revision for THA was lower for women from 60 to 69 years old (HR = 0.58 [95% confidence interval (CI), 0.39 to 0.85]) and from 70 to 74 years old (HR = 0.65 [95% CI, 0.43 to 0.98]) compared with HA. However, women from 80 to 85 years old (HR = 1.56 [95% CI, 1.03 to 2.35]) and men from 75 to 79 years old (HR = 1.61 [95% CI, 1.05 to 2.46]) and 80 to 85 years old (HR = 2.73 [95% CI, 1.89 to 3.95]) had an increased rate of revision when THA was undertaken compared with HA. There was no difference in the rate of revision for dislocation between THA and HA for either sex or age categories.

CONCLUSIONS

When contemporary surgical options for FNF are used, there is a benefit with respect to revision outcomes for THA in women who are <75 years old and a benefit for HA in women who are ≥80 years old and men who are ≥75 years old. There is no difference in dislocation rates.

LEVEL OF EVIDENCE

Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

A Comparison of Revision Rates and Dislocation After Primary Total Hip Arthroplasty with 28, 32, and 36-mm Femoral Heads and Different Cup Sizes: An Analysis of 188,591 Primary Total Hip Arthroplasties

This article was updated on August 17, 2022, because of previous errors, which were discovered after the preliminary version of the article was posted online. On page 1462, in the first sentence of the Abstract section entitled "Results," the phrase that had read "and 36-mm heads had fewer dislocations than 28-mm (HR = 0.33 [95% CI, 0.16 to 0.68]; p = 0.003), but more dislocations than 32-mm heads (HR for >2 weeks = 2.25 [95% CI, 1.13 to 4.49]; p = 0.021)" now reads "and 36-mm heads had fewer dislocations than 28-mm (HR = 0.33 [95% CI, 0.16 to 0.68]; p = 0.003) and 32-mm heads (HR for ≥2 weeks = 0.44 [95% CI, 0.22 to 0.88]; p = 0.021)." On page 1468, in the last sentence of the section entitled "Acetabular Components with a Diameter of <51 mm," the phrase that had read "and HR for ≥2 weeks = 2.25 [95% CI, 1.13 to 4.49; p = 0.021]) ( Fig. 3 )" now reads "and HR for ≥2 weeks = 0.44 [95% CI, 0.22 to 0.88; p = 0.021]) ( Fig. 3 )." Finally, on page 1466, in the upper right corner of Figure 3 , under "32mm vs 36mm," the second line that had read "2Wks+: HR=2.25 (1.13, 4.49), p=0.021" now reads "2Wks+: HR=0.44 (0.22, 0.88), p= 0.021."

Outcome and risk factors of failures associated with revision total hip arthroplasty for recurrent dislocation

INTRODUCTION

Recurrent dislocation represents the third most common cause of revision surgery after total hip arthroplasty (THA). However, there is a paucity of information on the outcome of revision total hip arthroplasty for recurrent dislocation. In this study, we investigated (1) clinical outcomes of patients that underwent revision THA for recurrent dislocation, and (2) potential risk factors associated with treatment failure in patients who underwent revision total hip arthroplasty for recurrent dislocation.

METHODS

We retrospectively reviewed 211 consecutive cases of revision total hip arthroplasty for recurrent dislocation, 81 implanted with a constrained liner and 130 with a non-constrained liner with a large-diameter femoral head (> 32 mm). Patient- and implant-related risk factors were analyzed in multivariate regression analysis.

RESULTS

At 4.6-year follow-up, 32 of 211 patients (15.1%) underwent re-revision surgery. The most common causes for re-revision included infection (14 patients) and dislocation (10 patients). Kaplan-Meier analysis demonstrates a 5-year survival probability of 77% for patients that underwent revision THA for recurrent dislocation. Osteoporosis, obesity (BMI ≥ 40), spine disease and abductor deficiency are independent risk factors for failure of revision surgery for recurrent dislocation. Liner type (constrained vs. non-constrained) was found not to be associated with failure of revision THA for recurrent dislocation (p = 0.44).

CONCLUSION

This study suggests that THA revision for recurrent dislocation is associated with a high re-revision rate of 15% at mid-term follow-up. Osteoporosis, obesity (BMI ≥ 40) spine disease and abductor deficiency were demonstrated to be independent risk factors for failure of revision THA for recurrent dislocation.

LEVEL OF EVIDENCE

Level III, case-control retrospective analysis.

In Revision THA, Is the Re-revision Risk for Dislocation and Aseptic Causes Greater in Dual-mobility Constructs or Large Femoral Head Bearings? A Study from the Australian Orthopaedic Association National Joint Replacement Registry

BACKGROUND

Dislocation is one of the most common causes of a re-revision after a revision THA. Dual-mobility constructs and large femoral head bearings (≥ 36 mm) are known options for mitigating this risk. However, it is unknown which of these choices is better for reducing the risk of dislocation and all-cause re-revision surgery. It is also unknown whether there is a difference between dual-mobility constructs and large femoral head bearings according to the size of the acetabular component.

QUESTIONS/PURPOSES

We used data from a large national registry to ask: In patients undergoing revision THA for aseptic causes after a primary THA performed for osteoarthritis, (1) Does the proportion of re-revision surgery for prosthesis dislocation differ between revision THAs performed with dual-mobility constructs and those performed with large femoral head bearings? (2) Does the proportion of re-revision surgery for all aseptic causes differ between revision THAs performed with dual-mobility constructs and those performed with large femoral head bearings? (3) Is there a difference when the results are stratified by acetabular component size?

METHODS

Data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) were analyzed for 1295 first-revision THAs for aseptic causes after a primary THA performed for osteoarthritis. The study period was from January 2008-when the first dual-mobility prosthesis was recorded-to December 2019. There were 502 dual-mobility constructs and 793 large femoral head bearings. There was a larger percentage of women in the dual-mobility construct group (67% [334 of 502]) compared with the large femoral head bearing group (51% [402 of 793]), but this was adjusted for in the statistical analysis. Patient ages were similar for the dual-mobility construct group (67 ± 11 years) and the large femoral head group (65 ± 12 years). American Society of Anesthesiologists (ASA) class and BMI distributions were similar. The mean follow-up was shorter for dual-mobility constructs at 2 ± 1.8 years compared with 4 ± 2.9 years for large femoral head bearings. The cumulative percent revision (CPR) was determined for a diagnosis of prosthesis dislocation as well as for all aseptic causes (excluding infection). Procedures using metal-on-metal bearings were excluded. The time to the re-revision was described using Kaplan-Meier estimates of survivorship, with right censoring for death or database closure at the time of analysis. The unadjusted CPR was estimated each year of the first 5 years for dual-mobility constructs and for each of the first 9 years for large femoral head bearings, with 95% confidence intervals using unadjusted pointwise Greenwood estimates. The apparent shorter follow-up of the dual-mobility construct group relates to the more recent increase in dual-mobility numbers recorded in the registry. The results were adjusted for age, gender, and femoral fixation. Results were subanalyzed for acetabular component sizes < 58 mm and ≥ 58 mm, set a priori on the basis of biomechanical and other registry data.

RESULTS

There was no difference in the proportion of re-revision for prosthesis dislocation between dual-mobility constructs and large femoral head bearings (hazard ratio 1.22 [95% CI 0.70 to 2.12]; p = 0.49). At 5 years, the CPR of the re-revision for prosthesis dislocation was 4.0% for dual mobility constructs (95% CI 2.3% to 6.8%) and 4.1% for large femoral head bearings (95% CI 2.7% to 6.1%). There was no difference in the proportion of all aseptic-cause second revisions between dual-mobility constructs and large femoral head bearings (HR 1.02 [95% CI 0.76 to 1.37]; p = 0.89). At 5 years, the CPR of dual-mobility constructs was 17.6% for all aseptic-cause second revision (95% CI 12.6% to 24.3%) and 17.8% for large femoral head bearings (95% CI 14.9% to 21.2%). When stratified by acetabular component sizes less than 58 mm and at least 58 mm, there was no difference in the re-revision CPR for dislocation or for all aseptic causes between dual-mobility constructs and large femoral head bearings.

CONCLUSION

Either dual-mobility constructs or large femoral head bearings can be used in revision THA, regardless of acetabular component size, as they did not differ in terms of re-revision rates for dislocation and all aseptic causes in this registry study. Longer term follow-up is required to assess whether complications develop with either implant or whether a difference in revision rates becomes apparent. Ongoing follow-up and comparison in a registry format would seem the best way to compare long-term complications and revision rates. Future studies should also compare surgeon factors and whether they influence decision-making between prosthesis options and second revision rates. Nested randomized controlled trials in national registries would seem a viable option for future research.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Fragility Fracture Systems: International Perspectives - Asia & Australia

Background:

The incidence and burden of fragility fractures have reached the level where comprehensive systematic care is warranted to optimize the care of these patients. Hip fractures are the most frequently lethal and independence level changing fragility fractures, responsible for 30-day mortality comparable to high-energy trauma patients with injury severity scores over 12. It is a reasonable expectation that countries have a hip fracture treating system of care in place for this high-risk population. This review explores the systems of care from the Asia-Pacific Perspective.

Methods:

From the International Orthopaedic Trauma Association's member societies, nations from the Asia-Pacific Region were requested to contribute with an overview of their fragility fracture management systems. The content or the review was standardized by a template of headings, which each country endeavored to cover.

Results:

Australia, Japan, and South Korea contributed voluntarily from the 5 member countries of the region. Each country has made considerable efforts and achievements with diverse approaches to standardize and improve the care of fragility fractures, particularly hip fractures. Beyond the individual nations’ efforts there is also an existing Asia-Pacific Collaborative. The data collection and in some counties the existence of a registry is promising; funding and recognition of the problem among competing health care budget priorities are common.

Conclusions:

Our review covers some of the countries with strongest economy and highest health care standards. The lack of a universal robust system for hip fracture care is apparent. The data collection from registry initiations is expected to drive system development further in these countries and hopefully fast track the development in other countries within the most populous geographical region of the Earth.

Dual-mobility constructs versus large femoral head bearings in primary and revision total hip arthroplasty: a systematic review and meta-analysis of comparative studies

BACKGROUND

Both dual-mobility (DM) constructs and large femoral head bearings (⩾36 mm) reduce dislocation following total hip arthroplasty (THA). There is limited research comparing DM with large bearings.

METHODS

A systematic review of published literature was performed including studies that compared DM with large femoral head bearings in primary or revision THA according to PRISMA guidelines. The primary outcome was revision surgery for dislocation. The secondary outcome was all-cause revision surgery. Other complications were recorded. 2 authors independently selected studies, performed data extraction, and risk of bias assessment. Treatment effects were assessed using odds ratios and data were pooled using a fixed-effect model, where appropriate.

RESULTS

9 studies, all retrospective, met the final inclusion criteria. 2722 patients received DM and 9,789 large femoral head bearings. The difference in the odds of revision surgery for dislocation (OR 0.67; 95% CI, 0.45-1.01; p = 0.06) and aseptic loosening are unclear (OR 0.61; 95% CI, 0.36-1.05; p = 0.07); including important benefits and no difference. There was a benefit favouring DM for the risk of all-cause revision (OR 0.70; 95% CI, 0.56-0.86; p = 0.001), revision for fracture (OR 0.49; 95% CI, 0.29-0.81; p = 0.005) and dislocation not requiring revision (OR 0.29; 95% CI, 0.14-0.57; p < 0.001). The estimate in the difference in the odds of revision surgery for infection was imprecise (OR 0.78; 95% CI, 05.1-1.20; p = 0.26).

CONCLUSIONS

This study provides evidence that there may be clinically relevant benefits of DM constructs over large femoral head bearings. Prospective randomised studies are warranted given these findings.

Dislocation of Total Hip Replacement in Femoral Neck Fracture: Do Surgical Approach and Dual Mobility Implant Matter?

INTRODUCTION

Total hip replacement (THR) in the neck of femur fracture in the elderly is associated with a higher risk of dislocation compared to hemiarthroplasty of hip or total hip replacement in the native hip. There is uncertainty regarding combining surgical approach, femoral head size, and the usage of single bearing or dual mobility to reduce the risk of dislocation. This study looks into the bearing of the prosthesis for posterior or lateral surgical hip approach as well as their head size to give a stable hip to these vulnerable groups of patients.

METHODS

Initial data were collected retrospectively from February 2017 till May 2019 from the electronic records database and clinical notes. Patients included in the study had a femoral neck fracture (age >60 years) who underwent a total hip replacement. Subsequent data were collected prospectively from June 2019 to July 2020.

RESULTS

High rate of dislocation was found with posterior approach and single bearing prosthesis. However, if dual mobility prosthesis was used while using the posterior approach the dislocation rate was very low. Also, with lateral approach and single bearing prosthesis using large femoral head size, the dislocation rate was negligible.

CONCLUSIONS

We recommend a dual mobility prosthesis for posterior approach THR and lateral approach with single-bearing hip replacement with large size femoral head. The dislocation rate is low using this principle irrespective of the surgical approach.

Total, hemi, or dual-mobility arthroplasty for the treatment of femoral neck fractures in patients with neurological disease : analysis of 9,638 patients from the Swedish Hip Arthroplasty Register

AIMS

The aim of this study was to investigate the potentially increased risk of dislocation in patients with neurological disease who sustain a femoral neck fracture, as it is unclear whether they should undergo total hip arthroplasty (THA) or hemiarthroplasty (HA). A secondary aim was to investgate whether dual-mobility components confer a reduced risk of dislocation in these patients.

METHODS

We undertook a longitudinal cohort study linking the Swedish Hip Arthroplasty Register with the National Patient Register, including patients with a neurological disease presenting with a femoral neck fracture and treated with HA, a conventional THA (cTHA) with femoral head size of ≤ 32 mm, or a dual-mobility component THA (DMC-THA) between 2005 and 2014. The dislocation rate at one- and three-year revision, reoperation, and mortality rates were recorded. Cox multivariate regression models were fitted to calculate adjusted hazard ratios (HRs).

RESULTS

A total of 9,638 patients with a neurological disease who also underwent unilateral arthroplasty for a femoral neck fracture were included in the study. The one-year dislocation rate was 3.7% after HA, 8.8% after cTHA < 32 mm), 5.9% after cTHA (= 32 mm), and 2.7% after DMC-THA. A higher risk of dislocation was associated with cTHA (< 32 mm) compared with HA (HR 1.90 (95% confidence interval (CI) 1.26 to 2.86); p = 0.002). There was no difference in the risk of dislocation with DMC-THA (HR 0.68 (95% CI 0.26 to 1.84); p = 0.451) or cTHA (= 32 mm) (HR 1.54 (95% CI 0.94 to 2.51); p = 0.083). There were no differences in the rate of reoperation and revision-free survival between the different types of prosthesis and sizes of femoral head.

CONCLUSION

Patients with a neurological disease who sustain a femoral neck fracture have similar rates of dislocation after undergoing HA or DMC-THA. Most patients with a neurological disease are not eligible for THA and should thus undergo HA, whereas those eligible for THA could benefit from a DMC-THA. Cite this article: Bone Joint J 2022;104-B(1):134-141.

Cost-effectiveness of dual-mobility components in patients with displaced femoral neck fractures

AIMS

Total hip arthroplasty (THA) with dual-mobility components (DM-THA) has been shown to decrease the risk of dislocation in the setting of a displaced neck of femur fracture compared to conventional single-bearing THA (SB-THA). This study assesses if the clinical benefit of a reduced dislocation rate can justify the incremental cost increase of DM-THA compared to SB-THA.

METHODS

Costs and benefits were established for patients aged 75 to 79 years over a five-year time period in the base case from the Canadian Health Payer's perspective. One-way and probabilistic sensitivity analysis assessed the robustness of the base case model conclusions.

RESULTS

DM-THA was found to be cost-effective, with an estimated incremental cost-effectiveness ratio (ICER) of CAD $46,556 (£27,074) per quality-adjusted life year (QALY). Sensitivity analysis revealed DM-THA was not cost-effective across all age groups in the first two years. DM-THA becomes cost-effective for those aged under 80 years at time periods from five to 15 years, but was not cost-effective for those aged 80 years and over at any timepoint. To be cost-effective at ten years in the base case, DM-THA must reduce the risk of dislocation compared to SB-THA by at least 62%. Probabilistic sensitivity analysis showed DM-THA was 58% likely to be cost-effective in the base case.

CONCLUSION

Treating patients with a displaced femoral neck fracture using DM-THA components may be cost-effective compared to SB-THA in patients aged under 80 years. However, future research will help determine if the modelled rates of adverse events hold true. Surgeons should continue to use clinical judgement and consider individual patients' physiological age and risk factors for dislocation. Cite this article: Bone Joint J 2021;103-B(12):1783-1790.

A Comparison of Revision Rates for Dislocation and Aseptic Causes Between Dual Mobility and Large Femoral Head Bearings in Primary Total Hip Arthroplasty With Subanalysis by Acetabular Component Size: An Analysis of 106,163 Primary Total Hip Arthroplasties

BACKGROUND

Dual mobility (DM) and large femoral head bearings (≥36 mm) both decrease the risk of dislocation in total hip arthroplasty (THA). There is limited comparable data in primary THA. This study compared the revision rates for dislocation and aseptic causes between DM and large femoral heads and subanalyzed by acetabular component size.

METHODS

Data from the Australian Orthopedic Association National Joint Replacement Registry were analyzed for patients undergoing primary THA for osteoarthritis from January 2008 (the year of first recorded DM use) to December 2019. All DM and large femoral head bearings were identified. The primary outcome measure was the cumulative percent revision (CPR) for dislocation and for all aseptic causes. The results were adjusted by age, sex, and femoral fixation. A subanalysis was performed stratifying acetabular component diameter <58 m and ≥58 mm.

RESULTS

There were 4942 DM and 101,221 large femoral head bearings recorded. There was no difference in the CPR for dislocation (HR = 0.69 (95% CI 0.42, 1.13), P = .138) or aseptic causes (HR = 0.91 (95% CI 0.70, 1.18), P = .457). When stratified by acetabular component size, DM reduced the CPR for dislocation in acetabular component diameter <58 mm (HR = 0.55 (95% CI 0.30, 1.00), P = .049). There was no difference for diameter ≥58 mm. There was no difference in aseptic revision when stratified by acetabular component diameter.

CONCLUSION

There is no difference in revision rates for dislocation or aseptic causes between DM and large femoral heads in primary THA. When stratified by acetabular component size, DM reduces dislocation for acetabular component diameter <58 mm.

LEVEL OF EVIDENCE

Level III.

Hip Hemiarthroplasty for Fractured Neck of Femur Revised to Total Hip Arthroplasty: Outcomes Are Influenced by Patient Age Not Articulation Options

BACKGROUND

Hip hemiarthroplasty is the most common arthroplasty option for fractured neck of femur (FNOF). Revision to total hip arthroplasty (THA) is occasionally required. This study aimed to assess the outcome of hemiarthroplasty revised to THA and to assess the impact of femoral head size, dual mobility (DM), and constrained liners.

METHODS

All aseptic 1^st revisions reported to the Australian Joint Replacement Registry after hemiarthroplasty performed for FNOF when a THA was used as the revision procedure were included from September 1999 to December 2019. The primary outcome measure was the cumulative percent revision for all-causes and dislocation. The impact of prosthesis factors on revision THA was assessed: standard head THA (≤32 mm), large head THA (≥36 mm), DM, and constrained liners. Outcomes were compared using Kaplan Meyer and competing risk.

RESULTS

There were 96,861 hemiarthroplasties performed, with 985 revised to THA. The most common reasons for 1^st revision were loosening (49.3%), fracture (17.7%), and dislocation (11.0%). Of the hemiarthroplasty procedures revised to THA, 76 had a 2^nd revision. The most common reasons for 2^nd revision were fracture (27.6%), dislocation (26.3%), loosening (23.7%), and infection (18.4%). Femoral head size, DM, or constrained liner use did not alter the incidence of all-cause 2^nd revision. This did not change when solely looking at patients still alive. A 2^nd revision was more likely in patients aged <75 years.

CONCLUSION

The outcome of hemiarthroplasty performed for FNOF revised to THA is influenced by patient age, not by the articulation used.

Spine Fusions, Yoga Instructors, and Hip Fractures: The Role of Dual Mobility in Primary Total Hip Arthroplasty

BACKGROUND

Despite the increased use of dual mobility (DM) in primary total hip arthroplasty (THA), debate exists regarding the indications for its use. No specific algorithm exists to guide this decision-making process. Therefore, the purpose of this article is to summarize the currently available literature regarding the use of DM in primary THA and provide evidence-based guidelines based on specific patient populations and risk factors for instability.

METHODS

We reviewed the current literature for studies evaluating risk factors for dislocation in primary THA, as well as the clinical use and results of DM in primary THA. Based on the strength of the literature, we discuss the use of DM in specific patient populations. We provide a decision-making algorithm to determine whether a patient may be indicated for DM in primary THA.

RESULTS

Surgeons should consider preoperative patient demographics, risk factors for instability (eg, significant hip-spine issues), type of procedure to be performed (eg, conversion arthroplasty), and indications for surgery (eg, THA for femoral neck fracture). Based on this algorithmic assessment, DM may be warranted in the primary THA setting if a patient's combined risk reaches an established threshold based on the literature.

CONCLUSION

This evidence-based algorithm may help guide current practice in the use of DM in primary THA. We advocate the continued judicious use of DM in hip arthroplasty. Longer term studies are needed in order to evaluate the durability of DM, as well as any complications related to the DM articulation.

Total hip arthroplasty in acetabular fractures

Total Hip Arthroplasty (THA) is a well-accepted treatment for established hip arthritis following acetabular fractures. If a conservatively managed or operated case progresses to non-union/mal-union failing to restore the joint integrity, it may eventually develop secondary arthritis warranting a total hip arthroplasty. Also, in recent years, acute total hip arthroplasty is gaining importance in conditions where the fracture presents with pre-existing hip arthritis, is not amenable to salvage by open reduction and internal fixation, or, a poor prognosis is anticipated following fixation. There are several surgical challenges in performing total hip arthroplasty for acetabular fractures whether acute or delayed. As a separate entity elderly patients pose a distinct challenge due to osteoporosis and need stable fixation for early weight bearing alleviating the risk of any thromboembolic event, pulmonary complications and decubitus ulcer. The aim of surgery is to restore the columns for acetabular component implantation rather than anatomic fixation. Meticulous preoperative planning with radiographs and Computed Tomography (CT) scans, adequate exposure to delineate the fracture pattern, and, availability of an array of all instruments and possible implants as backup are the key points for success. Previous implants if any should be removed only if they are in the way of cup implantation or infected. Press fit uncemented modern porous metal acetabular component with multiple screw options is the preferred implant for majority of cases. However, complex fractures may require major reconstruction with revision THA implants especially when a pelvic discontinuity is present.