Arthroplasty Register Research Articles

Development of a patient-centred tool for use in total hip arthroplasty.

The aim of this project was to develop a tool using the experience of previous patients to inform patient-centred clinical decision-making in the context of total hip arthroplasty (THA). We sought out the patients' views on what is important for them, leveraging registry data, and providing outcome information that is perceived as relevant, understandable, adapted to a specific patient's profile, and readily available. We created the information tool "Patients like me" in four steps. (1) The knowledge basis was the systematically collected detailed exposure and outcome information from the Geneva Arthroplasty Registry established 1996. (2) From the registry we randomly selected 275 patients about to undergo or having already undergone THA and asked them via interviews and a survey which benefits and harms associated with the operation and daily life with the prosthesis they perceived as most important. (3) The identified relevant data (39 predictor candidates, 15 outcomes) were evaluated using Conditional Inference Trees analysis to construct a classification algorithm for each of the 15 outcomes at three different time points/periods. Internal validity of the results was tested using bootstrapping. (4) The tool was designed by and pre-tested with patients over several iterations. Data from 6836 primary elective THAs operated between 1996 and 2019 were included. The trajectories for the 15 outcomes from the domains pain relief, activity improvement, complication (infection, dislocation, peri-prosthetic fracture) and what to expect in the future (revision surgery, need for contralateral hip replacement) over up to 20 years after surgery were presented for all patients and for specific patient profiles. The tool was adapted to various purposes including individual use, group sessions, patient-clinician interaction and surgeon information to complement the preoperative planning. The pre-test patients' feedback to the tool was unanimously positive. They considered it interesting, clear, complete, and complementary to other information received. The tool based on a survey of patients' perceived concerns and interests and the corresponding long-term data from a large institutional registry makes past patients' experience accessible, understandable, and visible for today's patients and their clinicians. It is a comprehensive illustration of trajectories of relevant outcomes from previous "Patients like me". This principle and methodology can be applied in other medical fields.

Anatomical site of radiographic degeneration is an independent variable influencing outcome of total knee arthroplasty

ObjectivesWe aimed to determine whether the site of anatomical degenerative change could be identified as an independent risk factor influencing clinical outcome of total knee arthroplasty (TKA) 12 months postoperatively. MethodsWe compared preoperative, postoperative and the change observed in Oxford Knee Score (OKS) amongst TKA patients categorised as primarily medial, lateral or patellofemoral osteoarthritis (PFJOA). Multivariable regression analysis was conducted on 434 consecutive knees in 333 patients, adjusting for sex, age and body mass index (BMI). ResultsAdjusted estimates showed that preoperatively, patients with medial and lateral osteoarthritis (OA) had a lower mean OKS of 2.1 (p ​= ​0.049) and 2.3 (p ​= ​0.056) points respectively, while those with PFJOA had mean scores 2.7 points higher (p ​= ​0.062). There was no statistically significant difference between compartments in absolute postoperative OKS. The greatest improvement of 30.1 points (95% confidence interval (CI) 16.9–36.0, p ​= ​0.012) in OKS was observed for those with lateral OA, followed by 28.9 points (95% CI 16.7–35.3, p ​= ​0.049) for those with medial OA. The improvement observed postoperatively in patients with PFJOA was less than that observed for the average of the cohort at 24.5 (95% CI 11.5–29.7, p ​= ​0.088). ConclusionsThe site of compartmental involvement in knee OA is an independent factor influencing clinical outcome of TKA. With arthroplasty registry adoption of patient-reported outcome measures (PROMs), this study supports precise anatomical categorisation of knee OA in outcome studies. Level of EvidenceLevel III, Retrospective consecutive clinical study.

The Tyrolean Federal Institute for Integrated Care (LIV Tyrol)

A constantly increasing life expectancy of society leads to an increase in severe chronic diseases, which are accompanied by negative effects on the quality of life for patients and an increasing number of hospital admissions as well as long hospital stays. This poses major challenges for the healthcare system and requires innovative and integrated approaches in order to provide high quality healthcare.
 Therefore, the Tyrolean Federal Institute for Integrated Care (LIV Tyrol) was founded from a joint initiative of the federal state government of the Province of Tyrol and the social insurance institutions to target the above mentioned challenges and reduce burdens for the health care system by developing and implementing integrated care approaches and programs for different chronic diseases. Integrated care is understood to be patient-oriented, continuous, cross-sectoral, interdisciplinary and/or multiprofessional care based on standardized care concepts.
 LIV Tyrol aims for optimal care for patients – especially patients suffering from chronic diseases – at their homes in order to increase their quality of life on the one hand and, on the other hand, to relieve the healthcare system through innovative approaches. As a result, different disease management programs are developed, implemented, coordinated, operated and evaluated.
 They include disease management programs for patients with heart failure (HerzMobil Tirol), dementia (Demenz Tirol), patients who suffered a stroke (Schlaganfallpfad Tirol) or in need of palliative care (Hospiz- und Palliativversorgung). LIV Tyrol also coordinates the care management for the Province of Tyrol, Austria and the post-Covid care. Some of these programs are supported by telemedical solutions including telemonitoring systems to provide a secure framework for patient care outside the hospital and to allow for immediate measures when needed. Furthermore, different registries, such as the Austrian birth registry, the Tyrolean cancer registry, the Tyrolean arthroplasty registry, or the Tyrolean diabetes registry are located and operated at the Institute of Clinical Epidemiology, which is part of LIV Tyrol. LIV Tyrol also supports data management and analytics for (clinical) problems but also provides an important contribution to quality assurance within the Tyrolean healthcare system.
 In order to implement such disease management programs, a close collaboration of different stakeholders is needed. Stakeholders of LIV Tyrol include but are not limited to health-policy makers, social insurance institutions, healthcare providers (hospitals, resident practitioners, other health-related professions), research institutions, and patients. 
 An institution like LIV Tyrol is unique in the Austrian health care system and contributes to optimal care security for patients in Tyrol and poses hub for new, innovative and flexible integrated care models.
 To make the health care system fit for the future, the federal and state governments have agreed to expand integrated care. The federal government of Tyrol has therefore commissioned the Tyrolean Federal Institute for Integrated Care to implement these targets and to design, organize and coordinate integrated care initiatives throughout the province of Tyrol.

Temporal trends in revision rate due to knee periprosthetic joint infection: a study of 115,120 cases from the Danish Knee Arthroplasty Register.

We aimed to examine the temporal trends in periprosthetic joint infection (PJI) revision incidence after knee arthroplasty (KA) from 1997 through 2019. 115,120 primary KA cases from the Danish Knee Arthroplasty Register were followed until the first PJI revision. We computed cumulative incidences and adjusted hazard ratios (aHRs) of PJI revision by calendar periods and several patient- and surgical-related risk factors. Results were analyzed from 0-3 months and from 3-12 months after KA. The overall 1-year PJI revision incidence was 0.7%, increasing from 0.5% to 0.7% (1997 through 2019). The incidence of PJI revision within 3 months increased from 0.1% to 0.5% (1997 through 2019). The adjusted hazard ratio (aHR) within 1 year of primary KA was 5.1 comparing 2017-2019 with 2001-2004. The PJI revision incidence from 3-12 months of KA decreased from 0.4% to 0.2%, with an aHR of 0.5 for 2017-2019 vs. 2001-2004. Male sex, age 75-84 (vs. 65-74), and extreme obesity (vs. normal weight) were positively associated with the risk of PJI revision within 3 months, whereas only male sex was associated from 3-12 months. Partial knee arthroplasty (PKA) vs. total KA was associated with a lower risk of PJI revision both within 3 months and 3-12 months of KA. We observed an increase in PJI revision within 3 months of KA, and a decrease in PJI revision incidence from 3-12 months from 1997 through 2019. The reasons for this observed time-trend are thought to be multifactorial. PKA was associated with a lower risk of PJI revision.

Outcomes of total ankle replacement – Current evidence

Total ankle replacement surgery is gaining popularity and is beginning to establish itself as a viable alternative to arthrodesis in the treatment of end-stage ankle arthritis. Only a few studies exist directly comparing these 2 techniques. Also lacking are the long-term outcome studies of ankle replacement surgery. A better understanding of clinical and patient-reported outcome measures after ankle fusion and replacement will enable the surgeon to better counsel the patient and help choose the right treatment. This article will summarise the reported clinical outcomes after total ankle replacements and survivorship analysis from the various national arthroplasty registers.

Why are Joint Replacement Registries Needed? Part 2. Overview of Several National Registries of Knee Arthroplasty

Summary. Joint replacement registries are well established and have an important impact on decision making and clinical practice. The objective of this article is to review orthopedic registries to examine aspects of patient demographics, implant use, and revision outcomes in relation to knee replacement surgery. Six best known national arthroplasty registries with more than 10 years of data were selected for a review. Despite the geographic diversity, the demographics of patients referred for surgery and subcategories of surgeries were remarkably similar. For a cemented total knee replacement, minimally stabilized devices have been preferred in most countries, and a revision-free result can be expected in more than 94% of cases after 10 years. Partial replacement (lateral lateral or medial unicompartmental) was used in 6% to 15% of primary cases and had higher revision rates than total replacement, but had lower postoperative mortality and fewer infectious complications. Patellofemoral replacements are used in 1% or less of cases and have a high revision rate.

The Delta III and Delta Xtend reverse shoulder arthroplasty—risk of revision and failure mechanisms: a report on 3650 cases from the Norwegian Arthroplasty Register 1994-2021

The Delta reverse shoulder arthroplasty (RSA) is commonly used worldwide and is the most frequently used RSA in Norway. The aim of this registry-based study was to report 10- and 20-year implant survival, risk of revision, and reasons for revision in 2 consecutive time periods for Delta III (1994-2010) and Delta Xtend (2007-2021) prostheses. We included 3650 primary RSAs reported to the Norwegian Arthroplasty Register: 315 Delta III (42% cemented stems) and 3335 Delta Xtend (88% cemented stems). We used Kaplan-Meier analyses to investigate implant survival. The reasons for revision were compared for the 2 designs and fixation technique. Factors that could influence the risk of revision, such as implant design, fixation technique, and patient factors, were investigated using Cox regression analyses with adjustments for age, sex, and diagnosis. Patients operated with Delta III were more likely to be diagnosed with inflammatory disease or fracture sequela, whereas acute fracture, osteoarthritis, and cuff arthropathy were the most frequent indications for Delta Xtend. Ten-year survival was 93.0% (95% confidence interval [CI]: 87.0-99.0) (cemented stem) and 81.6% (95% CI: 75.3-87.9) (uncemented stem) for Delta III and 94.7% (95% CI: 93.3-96.1) (cemented stem) and 95.7% (95% CI: 88.3-100) (uncemented stem) for Delta Xtend. Twenty-year survival for Delta III (uncemented stem) was 68.2% (95% CI: 58.8-77.6). Compared with DeltaXtend (cemented stem) at 10-year follow-up, we found a higher risk of revision for Delta III (uncemented stem) (hazard ratio [HR]: 2.9, 95% CI: 1.7-5.0), whereas no significant difference was found for Delta III (cemented stem) and Delta Xtend (uncemented stem). The most common reason for revision of Delta III (uncemented stem) was glenoid loosening followed by deep infection and instability. Instability was the most frequent revision cause for Delta Xtend (both cemented and uncemented stem). Men had an overall higher revision risk than women (HR: 2.8 [95% CI: 2.0-3.9]), and patients with fracture sequela had increased risk for revision (HR: 2.8, 95% CI: 1.7-4.7) compared with patients with osteoarthritis. We found that Delta III (uncemented stem) had a higher risk of revision compared with Delta Xtend (cemented stem). The risk of revision for glenoid component loosening was lower for Delta Xtend, but revisions due to instability/dislocation are still a concern. This register study cannot determine whether the differences found were caused by differences in implant design or other factors that changed during the study period. Risk of revision may have been affected by the indication for primary operation.

Increased risk of aseptic loosening for posterior stabilized compared with posterior cruciate-retaining uncemented total knee replacements: a cohort study of 13,667 knees from the Dutch Arthroplasty Registry.

While registry studies have suggested a higher risk of revision for posterior-stabilized (PS) compared with posterior cruciate-retaining (CR) total knee replacements (TKR) using cement, it is unknown whether this is also the case for uncemented TKR. We aimed to compare the revision rates of PS and CR designs in patients receiving primary uncemented TKR. Data from the Dutch arthroplasty register (LROI) was analyzed, comprising 12,226 uncemented primary CR TKRs and 750 uncemented PS TKRs registered between 2007 and 2022. Competing risk and multivariable Cox regression analyses were used to compare revision rates, risks of revision, and reasons for revision between groups. Sensitivity analyses were performed to analyze the risk, concerning the 5 most commonly used implants and performing hospitals for each group. Uncemented PS TKRs had higher 10-year revision rates for any reason and aseptic loosening (6.5%, 95% confidence interval [CI] 4.6-9.2 and 3.9%, CI 2.6-6.7) compared with uncemented CR TKRs (4.2%, CI 3.8-4.7 and 1.4%, CI 1.2-1.7). PS TKRs were 1.4 and 2.5 times more likely to be revised for any reason and aseptic loosening, respectively. These results remained consistent after adjustment for age, sex, BMI, previous surgeries, bearing mobility, and surface modification, with sensitivity analyses. We found that uncemented PS implants have a higher rate of revision than uncemented CR implants, mainly due to a higher risk of aseptic loosening.

Why are joint arthroplasty registers needed? Part 1. (on the example of registers of knee arthroplasty)

This article examines the creation, assignment and management of knee arthroplasty registries. Methods of collecting relevant data, cost and ways of using thinformation are considered. Registries should strive to collect and analyze data of interest to both researchers and administrators. It is important to realize that without adequate research there will be no basis for real quality improvement. Registries have now become important tools in evidence-based practice. New implants and techniques are constantly being introduced, some of which do not work as expected. Registries will continue to be important tools for identifying problems and minimizing losses for years to come. They are important to the specialty as a whole because a well-documented profession is better equipped to compete for strained medical resources. Healthcare providers are more likely to provide funding when they can show past funding results, document treatment outcomes, and predict future trends.

Uncemented trabecular metal high-flex posterior-stabilized monoblock total knee arthroplasty in patients aged 60 years or younger

BackgroundUncemented trabecular metal (TM) monoblock tibial components in total knee arthroplasty (TKA) have shown excellent clinical results for up to 10 years. However, these studies were performed in highly specialized units, with few surgeons and often excluding knees with secondary osteoarthritis (OA), severe malalignments and previous surgery. The purpose of this study was to investigate implant survivorship and clinical and radiological outcome of the uncemented TM high-flex posterior stabilized (PS) monoblock tibial component in routine clinical practice. MethodsA retrospective study of 339 knees (282 patients) operated with the implant in routine clinical practice at two hospitals on patients aged 60 years or younger between 2007 and 2015. The operations were performed by 12 surgeons and there were no specific contraindications for use of the implant. Follow up ended in 2020. The status of the implant of deceased patients at death and those not attending follow up was checked with the Swedish Knee Arthroplasty Register. Clinical follow up consisted of clinical investigation, PROMs, and knee X-ray. ResultsFollow up was mean (range) 8.5 (5–13.8) years, and the 8-year survival rate was 0.98 (standard error 0.007). Five patients five knees) were deceased, five knees were revised (none due to aseptic loosening), and 16 patients did not attend the clinical follow up.Forty-four percent of the knees had secondary OA and 45% had had previous operations. 93% were satisfied or very satisfied with the operation and forgotten joint score (FJS) was median (interquartile range) 81 (44–94). Radiographic analysis revealed bone in close contact with the tibial tray and pegs in most cases, and in only 2% of the knees were potential radiolucent lines found. ConclusionThe results indicate that this uncemented implant performs excellently in routine clinical practice and also in younger patients with secondary OA or previous knee operations.

Does changes in unicompartmental knee arthroplasty practice pattern influence reasons for revision?

The aim of this study was to describe the pattern of revision indications for unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) and any change to this pattern for UKA patients over the last 20 years, and to investigate potential associations to changes in surgical practice over time. All primary knee arthroplasty surgeries performed due to primary osteoarthritis and their revisions reported to the Danish Knee Arthroplasty Register from 1997 to 2017 were included. Complex surgeries were excluded. The data was linked to the National Patient Register and the Civil Registration System for comorbidity, mortality, and emigration status. TKAs were propensity score matched 4:1 to UKAs. Revision risks were compared using competing risk Cox proportional hazard regression with a shared γ frailty component. Aseptic loosening (loosening) was the most common revision indication for both UKA (26.7%) and TKA (29.5%). Pain and disease progression accounted for 54.6% of the remaining UKA revisions. Infections and instability accounted for 56.1% of the remaining TKA revision. The incidence of revision due to loosening or pain decreased over the last decade, being the second and third least common indications in 2017. There was a decrease associated with fixation method for pain (hazard ratio (HR) 0.40; 95% confidence interval (CI) 0.17 to 0.94) and loosening (HR 0.29; 95% CI 0.10 to 0.81) for cementless compared to cemented, and units UKA usage for pain (HR 0.67, 95% CI 0.50 to 0.91), and loosening (HR 0.51; 95% CI 0.37 to 0.70) for high usage. The overall revision patterns for UKA and TKA for the last 20 years are comparable to previous published patterns. We found large changes to UKA revision patterns in the last decade, and with the current surgical practice, revision due to pain or loosening are significantly less likely.

In situ fixation of slipped capital femoral epiphysis carries a greater than 40% risk of later total hip arthroplasty during a long-term follow-up.

We aimed to assess the cumulative risk of total hip arthroplasty (THA) from in situ fixation for slipped capital femoral epiphysis (SCFE) after a follow-up of almost 50 years. In this study, 138 patients with 172 affected hips treated with in situ fixation were evaluated retrospectively. A total of 97 patients (70%) were male and the mean age was 13.6 years (SD 2.1); 35 patients (25%) had a bilateral disease. The median follow-up time was 49 years (interquartile range 43 to 55). Basic demographic, stability, and surgical details were obtained from patient records. Preoperative radiographs (slip angle; SA) were measured, and data on THA was gathered from the Finnish National Arthroplasty Register. The preoperative SA was a mean of 39° (SD 19°). At follow-up, 56 of the patients had undergone THA for a hip previously fixed in situ for SCFE (41%) and 64 of all affected hips had been replaced (37%). Kaplan-Meier analysis gave a median prosthesis-free postoperative survival of 55 years (95% confidence interval (CI) 45 to 64) for the affected hips. In a multivariate analysis, female patients had a two-fold risk for THA (hazard ratio (HR) 2.42 (95% CI 1.16 to 5.07)) and a greater preoperative SA increased the risk of THA (HR 1.03 for every increment of 1° (95% CI 1.01 to 1.05)), while patient age at surgery, slip laterality, stability of slip, or diagnostic delay did not have a statistically significant effect on the risk of THA. SCFE treated primarily with in situ fixation may lead to THA in more than 40% of affected hips at a near 50-year follow-up. This risk is approximately 15-times the reported lifetime risk in the Finnish general population. Female sex and increasing preoperative SA significantly predicted higher risk of THA.

Primary reverse total shoulder arthroplasty for fractures requires more revisions than for degenerative conditions 1 year after surgery: an analysis from the Dutch Arthroplasty Register.

Although reverse total shoulder arthroplasty (RTSA) is considered a viable treatment strategy for proximal humeral fractures, there is an ongoing discussion of how its revision rate compares with indications performed in the elective setting. First, this study evaluated whether RTSA for fractures conveyed a higher revision rate than RTSA for degenerative conditions (osteoarthritis, rotator cuff arthropathy, rotator cuff tear, or rheumatoid arthritis). Second, this study assessed whether there was a difference in patient-reported outcomes between these 2 groups following primary replacement. Finally, the results of conventional stem designs were compared with those of fracture-specific designs within the fracture group. This was a retrospective comparative cohort study with registry data from the Netherlands, generated prospectively between 2014 and 2020. Patients (aged ≥ 18 years) were included if they underwent primary RTSA for a fracture (<4 weeks after trauma), osteoarthritis, rotator cuff arthropathy, rotator cuff tear, or rheumatoid arthritis, with follow-up until first revision, death, or the end of the study period. The primary outcome was the revision rate. The secondary outcomes were the Oxford Shoulder Score, EuroQol 5 Dimensions (EQ-5D) score, numerical rating scale score (pain at rest and during activity), recommendation score, and scores assessing change in daily functioning and change in pain. This study included 8753 patients in the degenerative condition group (mean age, 74.3±7.2 years) and 2104 patients in the fracture group (mean age, 74.3±7.8 years). RTSA performed for fractures showed an early steep decline in survivorship: Adjusted for time, age, sex, and arthroplasty brand, the revision risk after 1 year was significantly higher in these patients than in those with degenerative conditions (hazard ratio [HR], 2.50; 95% confidence interval, 1.66-3.77). Over time, the HR steadily decreased, with an HR of 0.98 at year 6. Apart from the recommendation score (which was slightly better within the fracture group), there were no clinically relevant differences in the patient-reported outcome measures after 12 months. Patients who received conventional stems (n=1137) did not have a higher likelihood of undergoing a revision procedure than those who received fracture-specific stems (n=675) (HR, 1.70; 95% confidence interval, 0.91-3.17). Patients undergoing primary RTSA for fractures have a substantially higher likelihood of undergoing revision within the first year following the procedure than patients with degenerative conditions preoperatively. Although RTSA is regarded as a reliable and safe treatment option for fractures, surgeons should inform patients accordingly and incorporate this information in decision making when opting for head replacement surgery. There were no differences in patient-reported outcomes between the 2 groups and no differences in revision rates between conventional and fracture-specific stem designs.

The Impact of Social Determinants of Health on Outcomes and Complications After Total Knee Arthroplasty: An Analysis of Neighborhood Deprivation Indices.

Social determinants of health (SDOH) are important factors in the delivery of orthopaedic care. The purpose of this study was to investigate the relationship between outcomes following total knee arthroplasty (TKA) and both the Social Vulnerability Index (SVI) and the Area Deprivation Index (ADI). The Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) database was utilized to identify TKA cases for inclusion. Demographic characteristics and medical history were documented. The SVI, its subthemes, and the ADI were analyzed. Outcome data included length of stay, discharge disposition, postoperative change in the Knee Injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS, JR), 90-day incidences of emergency department (ED) visits, readmission, death, deep venous thrombosis (DVT) and/or pulmonary embolism (PE), periprosthetic fracture, implant failure, periprosthetic joint infection (PJI), and all-cause reoperation. Database cross-referencing was completed to document aseptic and septic revisions beyond 90 days postoperatively. Bivariate quartile-stratified and multivariable analyses were used to associate deprivation metrics with outcomes. A total of 19,321 TKA cases met inclusion criteria. Baseline patient characteristics varied among the SVI and/or ADI quartiles, with patients of non-White race and with a greater number of comorbidities noted in higher deprivation quartiles. Higher SVI and/or ADI quartiles were correlated with an increased rate of discharge to a skilled nursing facility (p < 0.05). A higher SVI and/or ADI quartile was associated with increased incidences of ED visits and readmissions postoperatively (p < 0.05). DVT and/or PE and long-term aseptic revision were the complications most strongly associated with higher deprivation metrics. Upon multivariable analysis, greater length of stay and greater incidences of ED visits, readmissions, DVT and/or PE, and aseptic revision remained significantly associated with greater deprivation based on multiple metrics. Greater deprivation based on multiple SVI subthemes, the composite SVI, and the ADI was significantly associated with increased length of stay, non-home discharge ED visits, and readmissions. The SVI and the ADI may be important considerations in the perioperative assessment of patients who undergo TKA. Prognostic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Modern robotics platform associated with reduced 90-day complications in hospital setting

BACKGROUND: Early complications in total knee arthroplasty (TKA) associated with modern robotics platforms integrated with digital balancing technology have not been investigated. OBJECTIVE: The objective was to compare 90-day complication rates between a manual technique and a modern robotic-assisted ligament balancing TKA platform. METHODS: 895 primary TKA procedures from a single surgeon were retrospectively reviewed (614 manual TKA, 281 using a modern robotics platform with an integrated digitally controlled ligament balancing device). Post-operative complications within the 90-day episode of care were recorded by the Michigan Arthroplasty Registry Collaborative Quality Initiative. Differences in complication rates between techniques were further divided into inpatient hospital, outpatient hospital, and ambulatory surgery center (ASC) cohorts. RESULTS: In the pooled hospital cohort and inpatient hospital cohort, ‘Return to OR’ was significantly lower for the robotic assisted group (1.3% vs 5.2% and 0% vs 4.9%, respectively, p&lt; 0.0370). Specifically, the need for manipulation under anesthesia (MUA) was reduced for the robotics group (0.0% vs 2.5%, p= 0.0352). No differences in overall complication rate or cause of complication was found between manual and robotics cases for the hospital outpatient and ASC cohorts (p⩾ 0.68). CONCLUSION: Within the hospital setting, robotic assisted ligament balancing technology was associated with reduced 90-day postoperative complications for ‘Return to OR’ and MUA.

Development and validation of a clinical prediction model for 90-day venous thromboembolism risk following total hip and total knee arthroplasty: a multinational study

BackgroundThe risk of venous thromboembolism (VTE) following total hip arthroplasty (THA) and total knee arthroplasty (TKA) is 1.0% to 1.5%, despite uniform thromboprophylaxis. ObjectivesTo develop and validate a prediction model for 90-day VTE risk. MethodsA multinational cohort study was performed. For model development, records were used from the Oxford Royal College of General Practitioners Research and Surveillance Centre linked to Hospital Episode Statistics and Office of National Statistics UK routine data. For external validation, data were used from the Danish Hip and Knee Arthroplasty Registry, the National Patient Registry, and the National Prescription Registry. Binary multivariable logistic regression techniques were used for development. ResultsIn the UK data set, 64 032 THA/TKA procedures were performed and 1.4% developed VTE. The prediction model consisted of age, body mass index, sex, cystitis within 1 year before surgery, history of phlebitis, history of VTE, presence of varicose veins, presence of asthma, history of transient ischemic attack, history of myocardial infarction, presence of hypertension and THA or TKA. The area under the curve of the model was 0.65 (95% CI, 0.63-0.67). Furthermore, 36 169 procedures were performed in the Danish cohort, of whom 1.0% developed VTE. Here, the area under the curve was 0.64 (95% CI, 0.61-0.67). The calibration slope was 0.92 in the validation study and 1.00 in the development study. ConclusionThis clinical prediction model for 90-day VTE risk following THA and TKA performed well in both development and validation data. This model can be used to estimate an individual’s risk for VTE following THA/TKA.

Long-term follow-up and survival of delayed total hip arthroplasty following acetabular fracture: a matched cohort study of 552 cases from the Norwegian Arthroplasty Register.

Operative treatment of acetabular fractures generally yields good results, but several authors report up to 15-20% of patients developing post-traumatic osteoarthritis (OA). Previous studies have shown that total hip arthroplasty (THA) following post-traumatic OA have inferior results compared to THA for primary OA. The aim of this study was to report on long-term outcome of THA following acetabular fracture, compared to primary OA. We performed a matched cohort study with data from the Norwegian Arthroplasty Register (NAR). All patients receiving THA following an acetabular fracture between 1987 and 2018 were identified. A 3:1 matched cohort consisting of patients treated for primary OA with THA was selected using propensity scores and matched for age, gender and year of surgery. Survival analysis was performed with revision of any cause as endpoint. Cox regression was used to identify factors associated with risk of revision surgery. 552 cases were identified, 397 men and 155 women. Mean age was 58.8 (11-91) years. 224 had previously been operated for the acetabular fracture, 328 had been treated non-operatively. Mean follow up time was 8.7 (1-29) years. Implant survival at 10 years was 79.7% (75.6-83.3) and at 20 years 62.4% (55.5-69.3). The hazard ratio for revision was 1.38 (1.07-1.77, p < 0.001) compared to the OA cohort, regardless of operative or non-operative treatment of the index acetabular fracture. Uncemented acetabular components had an increased risk of revision with hazard ratio for revision 1.61 (p = 0.012). THA following an acetabular fracture can be performed with acceptable results regarding implant survival, however, we report an increased risk for revision when compared to primary OA. Our results indicate that previous operative fracture treatment does not increase the risk for THA revision compared to cases treated non-operatively.

Current design and cement mantle thickness in hip arthroplasty : Theory and analysis of register data

In this article, an overview and comparison of the most commonly used cemented hip stems, grouped into different stem types and cement mantle thickness, is given to see which combination performs well. Revision rates of cemented stem types were categorized from the Endoprosthesis Register-Germany, and 3‑ and 5‑year revision rates were reported and analyzed. For the research, the focus was on the Exeter, C‑Stem, MS-30, Excia, Bicontact, Charnley, Müller straight stem, Twinsys, Corail, Avenir, Quadra, and the Lubinus SPII stems. An important aspect was which stem is preferred to be implanted and which cementing technique is used with regard to the planned cement mantle thickness. In order to identify atrend in cemented hip arthroplasty, data from the Danish, Swedish, Norwegian, Swiss, New Zealand, English and Australian arthroplasty registers were also compared. Most countries use cemented prostheses according to the taper slip principle (Exeter, MS30, C‑Stem etc) or the composite beam (Charnley, Excia, Bicontact), which are implanted with acement mantle thickness of 2-4 mm. However, atrend has emerged in Germany and Switzerland towards the line-to-line technique, with aplanned cement mantle thickness of 1 mm (Twinsys, Corail, Avenir, Quadra), following the principle of the Müller straight stem prosthesis and the Kerboul-Charnley prosthesis, even though these are postulated to be "French paradoxes" in themselves. In the EPRD 5‑year results, the newer line-to-line prostheses seem to perform slightly worse. The best results are achieved by the "MS30" in Germany and the "Exeter" in England. These are polished straight stems with centralizer and subsidence space at the apex with a2-4 mm cement mantle in good cementing technique.

Can Dual Mobility Cups Reduce Revision and Dislocation Risks? An Analysis of 107,528 Primary Total Hip Arthroplasties in the United States

BackgroundDual mobility acetabular cups (DMC) were designed to increase the effective femoral head size and improve stability with the goal of reducing revision risk at the potential cost of polyethylene thickness. We sought to evaluate revision risk following primary elective total hip arthroplasty with DMC compared to highly cross-linked polyethylene (XLPE). MethodsA cohort study was conducted using data from a Kaiser Permanente’s total joint arthroplasty registry. Patients ≥18 years who underwent primary elective total hip arthroplasty using DMC, unipolar Metal-on-XLPE (MoXLPE), or unipolar Ceramic-on-XLPE (CoXLPE) were identified (2010 to 2021). The final sample comprised 2,219 DMC, 48,251 MoXLPE, and 57,058 CoXLPE. Multiple Cox proportional hazard regressions were used to evaluate aseptic revision and any dislocation regardless of revision within 6 years follow-up. ResultsIn adjusted analyses, no differences in aseptic revision risk were observed for MoXLPE (hazard ratio [HR] = 1.04, 95% confidence interval [CI] = 0.72 to 1.51) or CoXLPE (HR = 0.98, 95% CI = 0.69 to 1.40) compared to DMC. No differences in dislocation risk were observed for MoXLPE (HR = 1.42, 95% CI = 0.93 to 2.15) or CoXLPE (HR = 1.25, 95% CI = 0.84 to 1.87) compared to DMC. ConclusionsIn a US-based cohort, 6-year aseptic revision risk of DMC was similar to metal or ceramic femoral head unipolar constructs. Furthermore, no difference in dislocation risk was observed. Continued longer-term follow-up may reveal if there is a reduced risk of dislocation that comes at the cost of increased late revision. Level of EvidenceLevel III.

No clinically relevant difference in patient-reported outcomes between the direct superior approach and the posterolateral or anterior approach for primary total hip arthroplasty: analysis of 37,976 primary hip arthroplasties in the Dutch Arthroplasty Registry.

The direct superior approach (DSA) is a modification of the posterolateral approach (PLA) for total hip arthroplasty (THA). Patient-reported outcome measures (PROMs) of the DSA have not been investigated previously using nationwide data. Our aim was to assess PROMs after THA using the DSA compared with the PLA and, secondarily, with the anterior approach (DAA). In this population-based cohort study we included 37,976 primary THAs performed between 2014 and 2020 (PLA: n = 22,616; DAA: n = 15,017; DSA: n = 343) using Dutch Arthroplasty Registry data. PROMs (NRS pain, EQ-5D, HOOS-PS, and OHS) were measured preoperatively, and at 3 and 12 months postoperatively. Repeated measurements were analyzed using mixed-effects models, adjusted for confounders, to investigate the association between surgical approach and PROMs over time. From baseline to 3 and 12 months, improvements for NRS pain scores, EQ-5D, and OHS were comparable for the DSA compared with the PLA or DAA. No difference was found in HOOS-PS improvement 3 months postoperatively between DSA and PLA (-0.2, 95% confidence interval [CI] -2.4 to 1.9) and between DSA and DAA (-1.7, CI -3.9 to 0.5). At 12 months postoperatively, patients in the DSA group had improved -2.8 points (CI -4.9 to -0.6) more in HOOS-PS compared with the DAA, but not with the PLA group (-1.0, CI -3.2 to 1.1). Our study showed no clinically meaningful differences between the DSA and either PLA or DAA.