Introduction. This analysis aims to provide an update of the Level-IV Partners Arthroplasty Registry (PAR), a quality-improvement initiative and research data repository. Methods. The Harris Joint Registry was founded in 1969 and has since expanded to become the Partners Arthroplasty Registry (PAR). Today, the PAR captures data on total hip and total knee arthroplasties conducted at seven hospitals in Massachusetts. Over time, data has been sourced through independent collection at a single hospital, retrospective sourcing through the Research Patient Data Registry (RPDR), and currently through the Enterprise Data Warehouse (EDW). Various statistical methods analyzed changing trends of care provided to patients across affiliated institutions. PROMs collected in the PAR are the PROMIS Physical Function and Global Health Short Forms, the HOOS and KOOS. The registry is an associate member of ISAR and will incorporate the international implant library. Results. The PAR contains demographic, implant-specifics, and radiographic data for 45,645 primary arthroplasties and 8,400 revision surgeries from 1998 to 2018. The average recorded Charlson Comorbidity Index is 0.98. Average length of stay prior to home or care facility discharge decreased from 5.00 days in 2001 to 3.00 days in 2018. The average 30-day and 90-day mortality rates for 2018 were 0. 18% and 0.28%, respectively. Home discharge increased from 30.1% to 79.0% from 2001–2018. The values for these parameters are varied across the seven sites. Conclusion. The PAR can be used to develop best practices, analyze health-care economics, and promote evidence-based medicine. We are also developing a platform for registry development that can be exported by other hospitals that utilize an Epic-based record system. For any tables or figures, please contact the authors directly

Aims. The primary aim of this paper was to outline the processes involved in building the Partners Arthroplasty Registry (PAR), established in April 2016 to capture baseline and outcome data for patients undergoing arthroplasty in a regional healthcare system. A secondary aim was to determine the quality of PAR’s data. A tertiary aim was to report preliminary findings from the registry and contributions to quality improvement initiatives and research up to March 2019. Methods. Structured Query Language was used to obtain data relating to patients who underwent total hip or knee arthroplasty (THA and TKA) from the hospital network’s electronic medical record (EMR) system to be included in the PAR. Data were stored in a secure database and visualized in dashboards. Quality assurance of PAR data was performed by review of the medical records. Capture rate was determined by comparing two months of PAR data with operating room schedules. Linear and binary logistic regression models were constructed to determine if length of stay (LOS), discharge to a care home, and readmission rates improved between 2016 and 2019. Results. The PAR captured 16,163 THAs and TKAs between April 2016 and March 2019, performed in seven hospitals by 110 surgeons. Manual comparison to operating schedules showed a 100% capture rate. Review of the records was performed for 2,603 random operations; 2,298 (88.3%) had complete and accurate data. The PAR provided the data for three abstracts presented at international conferences and has led to preoperative mental health treatment as a quality improvement initiative in the participating institutions. For primary THA and TKA surgeries, the LOS decreased significantly (p < 0.001) and the rate of home discharge increased significantly (p < 0.001) between 2016 and 2019. Readmission rates did not correlated with the date of surgery (p = 0.953). Conclusion. The PAR has high rates of coverage (the number of patients treated within the Partners healthcare network) and data completion and can be used for both research purposes and quality improvement. The same method of creating a registry that was used in the PAR can be applied to hospitals using similar EMR systems. Cite this article: Bone Joint J 2020;102-B(7 Supple B):90–98

The Norwegian Arthroplasty Register (NAR) started collecting data on total hip arthroplasty (THA) in 1987. Very long-term results of implants for THA are scarce. We aimed to show long-term results for the three most used femoral stems, operated from 1987. We included the uncemented Corail femoral stem (n=66,309) and the cemented Exeter stem (n=35,050) both of which are currently in frequent use. In addition, we included the Charnley stem (n=32,578, in use until 2014). To ensure comparable conditions, stems fixated with low viscosity cement and stems revised due to infections were excluded. Differences in risk of revision (all reasons and stem revisions) were assessed with Kaplan-Meier and Cox regression analyses with adjustment for possible confounding from age, sex and diagnosis (OA, other). Stem revision was defined as a revision caused by loosening of the stem, dislocation, osteolysis in the femur, or periprosthetic femur fracture, and in which the femoral component was removed or exchanged. The median and max follow-up for Corail, Exeter and Charnley were 6.3 (33.1), 8.0 (34.2) and 13.1 (34.3) respectively. Thirty years survival estimates for Corail, Exeter and Charnley stems were 88.6% (CI:85.8–90.9%), 86.7% (83.7–89.2%) and 87.1% (85.4–88.5%) respectively with stem revision as endpoint, and 56.1% (CI:53.1–59.1%), 73.3% (70.5–76.1%) and 80.2% (78.4–82.0%) with all THA revisions as endpoint. Compared to the Corail, the Exeter (HRR=1.3, CI:1.2–1.4) and the Charnley (HRR=1.9, CI:1.7–2.1) had a significant higher risk of stem revision. Women 75 years and older had better results with the cemented stems. Analyses accounting for competing risk from other causes of revision did not alter the findings. The uncemented Corail stem performed well in terms of stem revisions for stem-related revision causes compared to two frequently used cemented stems with very long follow-up. The differences between the three stems were small

Aims. This study compares the re-revision rate and mortality following septic and aseptic revision hip arthroplasty (rTHA) in registry data, and compares the outcomes to previously reported data. Methods. This is an observational cohort study using data from the German Arthroplasty Registry (EPRD). A total of 17,842 rTHAs were included, and the rates and cumulative incidence of hip re-revision and mortality following septic and aseptic rTHA were analyzed with seven-year follow-up. The Kaplan-Meier estimates were used to determine the re-revision rate and cumulative probability of mortality following rTHA. Results. The re-revision rate within one year after septic rTHA was 30%, and after seven years was 34%. The cumulative mortality within the first year after septic rTHA was 14%, and within seven years was 40%. After multiple previous hip revisions, the re-revision rate rose to over 40% in septic rTHA. The first six months were identified as the most critical period for the re-revision for septic rTHA. Conclusion. The risk re-revision and reinfection after septic rTHA was almost four times higher, as recorded in the ERPD, when compared to previous meta-analysis. We conclude that it is currently not possible to assume the data from single studies and meta-analysis reflects the outcomes in the ‘real world’. Data presented in meta-analyses and from specialist single-centre studies do not reflect the generality of outcomes as recorded in the ERPD. The highest re-revision rates and mortality are seen in the first six months postoperatively. The optimization of perioperative care through the development of a network of high-volume specialist hospitals is likely to lead to improved outcomes for patients undergoing rTHA, especially if associated with infection. Cite this article: Bone Joint J 2024;106-B(6):565–572

The increasing number of total hip arthroplasty (THA) used in young patients will inevitably lead to more revision procedures at younger ages, especially since the outcome of primary THA in young patients is already inferior compared to older patients. However, these data are lacking in literature. The aim of this study was to determine the survival of both acetabular and femoral components placed during primary and revision hip arthroplasty in patients under 55 years using Dutch Arthroplasty Register (LROI) data. All primary THA registered in the LROI between 2007–2018 in patients under 55 years were selected (n=25,682). Subsequent cup- and stem revision procedures were included. Kaplan-Meier survival analyses were used to estimate the survival probability of primary and revised cup- and stem components. Mean follow-up of primary cups and stems was 5.8 years (SD 3.2) and 5.9 years (SD 3.2), respectively. In total, 659 cup revision procedures and 532 stem revision procedures were registered. Most common reason for cup revision was acetabular loosening (n=163), most common reason for stem revision was femoral loosening (n=202). Primary cup survival for any reason at 10 years follow-up was 96.1% (95%CI: 95.7–96.4). For primary stems, 10 year survival for any reason was 97.1% (95%CI: 96.7–97.3). Mean follow-up of all revision procedures was 4.1 years (SD 2.9). Out of 659 cup revisions, 113 cup re-revisions were registered. Survival of revised cups, with end-point cup re-revision for any reason was 82.2% (95%CI: 78.8–85.1) at 5 years follow-up. Out of 532 stem revisions, 89 stem re-revisions were registered. For revised stems, survival at 5 year follow-up, with endpoint stem re-revision for any reason was 82.0% (95%CI: 78.2–85.2). The outcome of revised acetabular and femoral components is worrisome, with a survival of 82% at 5 years follow-up. This information is valuable to provide realistic expectations for these young patients at time of primary THA

Primary uncemented femoral stems reported to the Norwegian arthroplasty register between 1987 and 2005 were included in this prospective observational study. There were 11 516 hips (9679 patients) and 14 different designs of stem. Kaplan-Meier survival probabilities and Cox regression were used to analyse the data. With aseptic loosening as the end-point, all currently used designs performed excellently with survival of 96% to 100% at ten years. With the end-point as stem revision for any cause, the long-term results of the different designs varied from poor to excellent, with survival at 15 years ranging between 29% and 97%. Follow-up for longer than seven years was needed to identify some of the poorly-performing designs. There were differences between the stems; the Corail, used in 5456 hips, was the most frequently used stem with a survival of 97% at 15 years. Male gender was associated with an increased risk of revision of × 1.3 (95% confidence interval 1.05 to 1.52), but age and diagnosis had no influence on the results. Overall, modern uncemented femoral stems performed well. Moderate differences in survival between well-performing stems should be interpreted with caution since the differences may be caused by factors other than the stem itself

We present the results for 4762 revision total hip arthroplasties with no previous infection in the hip, which were reported to the Norwegian Arthroplasty Register between 1987 and 2003. The ten-year failure rate for revised prostheses was 26% (95% CI 25 to 26). Cox regression analyses were undertaken separately for acetabular and femoral revision components. Cemented revision components without allograft was the reference category. For acetabular components, we found a significantly reduced risk of failure for uncemented revisions both with (relative risk (RR) = 0.66; 95% CI 0.43 to 0.99) and without (RR = 0.37; 95% CI 0.22 to 0.61) allograft. For femoral components, we found a significantly reduced risk of failure for uncemented revisions, both with (RR = 0.27; 95% CI 0.16 to 0.46) and without (RR = 0.22; 95% CI 0.11 to 0.46) unimpacted allograft. This reduced risk of failure also applied to cemented revision components with allograft (RR = 0.53; 95% CI 0.33 to 0.84) and with impaction bone grafting (RR = 0.34; 95% CI 0.19 to 0.62). Revision prostheses have generally inferior results when compared with primary prostheses. Recementation without allograft, and uncemented revision with bone impaction, were associated with worse results than the other revision techniques which we studied

There is an ongoing discussion on what bearing surfaces to use in different age groups of total hip replacement patients. We report results from uncemented total hip arthroplasty using ceramic on ceramic bearings reported to the Norwegian Arthroplasty Register in the period 1997–2014. Kaplan Meier and Cox regression analysis adjusting for age, gender and diagnosis was used to assess prosthesis survival at 10 and 15 years after primary operation and to report relative risk of revision. Endpoint was any revision. Comparison with the cemented Charnley prosthesis (n=17180), with metal-on-polyethylene articulations from the same time period was done. Results in age groups <55, 55–64, 65–74, >=75 were investigated. The following femur/cup combinations were used; Filler/Igloo (n=2590), Corail/Pinnacle (n=783), Corail/Duraloc (n=467), SCP Unique/Trilogy (n=363), Polar/R3 (n=253), ABGII/ABGII (n=131), other combinations (n=339). Alumina bearing was used in 3807 hips and Alumina-Zirconium composite bearings in 1119 hips. The overall ten and fifteen years unadjusted Kaplan Meier survivals were 94.8 % and 92.0 % respectively with no statistically significant difference between the brands. The cemented Charnley hip arthroplasty had 93.6 % survival at 15 years, and was not statistically significant different from the uncemented ceramic/ceramic group. The 10 years survival in the age groups <55, 55–64, 65–74, >=75 for the uncemented ceramic/ceramic group was 93.7%, 95.3%, 96.0% and 95.4% respectively with no difference between the uncemented brands and the cemented Charnley prosthesis. We found less revisions in patients >=75 in the Charnley group. In the ceramic on ceramic group 11 head fractures and 3 liner fractures were reported. The 15 years result of uncemented hip replacement with ceramic on ceramic bearing was good, and not different from the Charnley cemented arthroplasty in the age groups <75 years

The Japan National Register (JAR) for total hip arthroplasty (THA) was launched in 2006. The JAR office accumulates and processes all the data and reports annually. The comparative studies among the annual data from 2013 to 2016 reveal the current trend of THA in Japan.

Up to March 2016, 1,188 hospitals have participated in the JAR. Registration ratio of THA is supposed to be about 50% in 2016. From 2006 to 2016, 88.146 data collection forms were submitted for THA.

More than 65% of the patients are diagnosed with Developmental Dysplasia of the Hip in Japan. Recently, the anterior approaches, direct Anterior approach and anterolateral modified Watson-Jones approach, have increased. About 80% of implants are cementless, while 8.7% are cement. The major reasons for revision THA are aseptic loosening, osteolysis, and infection, while periprosthetic fracture and implant dislocation/instability increase currently.

A brief summary of the annual report of the JAR is available from The Japanese Society for Replacement Arthroplasty website at http://jsra.info/.

Aims. Our primary aim was to assess reoperation-free survival at one year after the index injury in patients aged ≥ 75 years treated with internal fixation (IF) or arthroplasty for undisplaced femoral neck fractures (uFNFs). Secondary outcomes were reoperations and mortality analyzed separately. Methods. We retrieved data on all patients aged ≥ 75 years with an uFNF registered in the Swedish Fracture Register from 2011 to 2018. The database was linked to the Swedish Arthroplasty Register and the National Patient Register to obtain information on comorbidity, mortality, and reoperations. Our primary outcome, reoperation, or death at one year was analyzed using restricted mean survival time, which gives the mean time to either event for each group separately. Results. Overall, 3,909 patients presenting with uFNFs were included. Of these patients, 3,604 were treated with IF and 305 with primary arthroplasty. There were no relevant differences in age, sex, or comorbidities between groups. In the IF group 58% received cannulated screws and 39% hook pins. In the arthroplasty group 81% were treated with hemiarthroplasty and 19% with total hip arthroplasty. At one year, 32% were dead or had been reoperated in both groups. The reoperation-free survival time over one year of follow-up was 288 days (95% confidence interval (CI) 284 to 292) in the IF group and 279 days (95% CI 264 to 295) in the arthroplasty group, with p = 0.305 for the difference. Mortality was 26% in the IF group and 31% in the arthroplasty group at one year. Reoperation rates were 7.1% in the IF group and 2.3% in the arthroplasty group. Conclusion. In older patients with a uFNF, reoperation-free survival at one year seems similar, regardless of whether IF or arthroplasty is the primary surgery. However, this comparison depends on the choice of follow-up time in that reoperations were more common after IF. In contrast, we found more early deaths after arthroplasty. Our study calls for a randomized trial comparing these two methods. Cite this article: Bone Jt Open 2024;5(2):86–92

Aims. Registry studies on modified acetabular polyethylene (PE) liner designs are limited. We investigated the influence of standard and modified PE acetabular liner designs on the revision rate for mechanical complications in primary cementless total hip arthroplasty (THA). Methods. We analyzed 151,096 primary cementless THAs from the German Arthroplasty Registry (EPRD) between November 2012 and November 2020. Cumulative incidence of revision for mechanical complications for standard and four modified PE liners (lipped, offset, angulated/offset, and angulated) was determined using competing risk analysis at one and seven years. Confounders were investigated with a Cox proportional-hazards model. Results. Median follow-up was 868 days (interquartile range 418 to 1,364). The offset liner design reduced the risk of revision (hazard ratio (HR) 0.68 (95% confidence interval (CI) 0.50 to 0.92)), while the angulated/offset liner increased the risk of revision for mechanical failure (HR 1.81 (95% CI 1.38 to 2.36)). The cumulative incidence of revision was lowest for the offset liner at one and seven years (1.0% (95% CI 0.7 to 1.3) and 1.8% (95% CI 1.0 to 3.0)). No difference was found between standard, lipped, and angulated liner designs. Higher age at index primary THA and an Elixhauser Comorbidity Index greater than 0 increased the revision risk in the first year after surgery. Implantation of a higher proportion of a single design of liner in a hospital reduced revision risk slightly but significantly (p = 0.001). Conclusion. The use of standard acetabular component liners remains a good choice in primary uncemented THA, as most modified liner designs were not associated with a reduced risk of revision for mechanical failure. Offset liner designs were found to be beneficial and angulated/offset liner designs were associated with higher risks of revision. Cite this article: Bone Joint J 2022;104-B(7):801–810

Aims. Patients with femoral neck fractures (FNFs) treated with total hip arthroplasty (THA) have an almost ten-fold increased risk of dislocation compared to patients undergoing elective THA. The surgical approach influences the risk of dislocation. To date, the influence of differing head sizes and dual-mobility components (DMCs) on the risk of dislocation has not been well studied. Methods. In an observational cohort study on 8,031 FNF patients with THA between January 2005 and December 2014, Swedish Arthroplasty Register data were linked with the National Patient Register, recording the total dislocation rates at one year and revision rates at three years after surgery. The cumulative incidence of events was estimated using the Kaplan-Meier method. Cox multivariable regression models were fitted to calculate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for the risk of dislocation, revision, or mortality, stratified by surgical approach. Results. The cumulative dislocation rate at one year was 8.3% (95% CI 7.3 to 9.3) for patients operated on using the posterior approach and 2.7% (95% CI 2.2 to 3.2) when using the direct lateral approach. In the posterior approach group, use of DMC was associated with reduced adjusted risk of dislocation compared to 32 mm heads (HR 0.21 (95% CI 0.07 to 0.68); p = 0.009). This risk was increased with head sizes < 32 mm (HR 1.47 (95% CI 1.10 to 1.98); p = 0.010). Neither DMC nor different head sizes influenced the risk of revision following the posterior approach. Neither articulation was associated with a statistically significantly reduced adjusted risk of dislocation in patients where the direct lateral approach was performed, although this risk was estimated to be HR 0.14 (95% CI 0.02 to 1.02; p = 0.053) after the use of DMC. DMC inserted through a direct lateral approach was associated with a reduced risk of revision for any reason versus THA with 32 mm heads (HR 0.36 (95% CI 0.13 to 0.99); p = 0.047). Conclusion. When using a posterior approach for THA in FNF patients, DMC reduces the risk of dislocation, while a non-significant risk reduction is seen for DMC after use of the direct lateral approach. The direct lateral approach is protective against dislocation and is also associated with a lower rate of revision at three years, compared to the posterior approach. Cite this article: Bone Joint J 2022;104-B(7):844–851

In 1975, Sweden started registering primary knee replacement surgeries based on the personal identity number. Individual-based registrations of primary total hip replacements started in 1992 and for hemiarthroplasties the registration started in 2006. The completeness of these registrations is estimated at 98% during the last 10-year period. The long history and high completeness allow for accurate calculations of population-based prevalence of joint replacement and trends over time. We used all data on primary joint replacements available in the Swedish Arthroplasty Register. The prevalence was calculated using number of alive patients with 1) at least one joint replacement 2) at least one hip replacement 3) at least one knee replacement at the end of each year from 2010 – 2021. Publicly available population numbers were retrieved from Statistics Sweden. We calculated total prevalence and prevalence per age in years. By the end of 2021, 3.2% of the Swedish population had at least one hip or knee replacement. This was an increase from 2.5% in 2010. Among 80-year-old, the prevalence was 17.5% for any joint replacement. For both hip and knee replacement and all ages, the prevalence was higher for women. For knee replacement, the 2021 prevalence peaked at the age of 89 (9,4%) while the prevalence continuously increased with age for hip replacements. A considerable proportion of the Swedish elderly population is living with at least one hip or knee replacement. The prevalence has increased during the last 12-year period for both hips and knees. An increasing prevalence may also affect the incidence of fractures and infections. Knowledge about the prevalence is fundamental for planning future demand for primary and revision hip and knee replacement

Although data on uncemented short stems are available, studies on cemented short-stemmed THAs are limited. These cemented short stems may have inferior long-term outcomes and higher femoral component fracture rates. Hence, we examined the long-term follow-up of cemented short Exeter stems used in primary THA. Within the Exeter stem range, 7 stems have a stem length of 125 mm or less. These stems are often used in small patients, in young patients with a narrow femoral canal or patients with anatomical abnormalities. Based on our local database, we included 394 consecutive cemented stems used in primary THA (n=333 patients) with a stem length ≤125 mm implanted in our tertiary referral center between 1993 and December 2021. We used the Dutch Arthroplasty Registry (LROI) to complete and cross-check the data. Kaplan-Meier survival analyses were performed to determine 20-year survival rates with stem revision for any reason, for septic loosening, for aseptic loosening and for femoral component fracture as endpoints. The proportion of male patients was 21% (n=83). Median age at surgery was 42 years (interquartile range: 30–55). The main indication for primary THA was childhood hip diseases (51%). The 20-year stem survival rate of the short stem was 85.4% (95% CI: 73.9–92.0) for revision for any reason and 96.2% (95%CI: 90.5–98.5) for revision for septic loosening. No stems were revised for aseptic femoral loosening. However, there were 4 stem fractures at 6.6, 11.6, 16.5 and 18.2 years of follow-up. The stem survival with femoral component fracture as endpoint was 92.7% (CI: 78.5–97.6) at 20 years. Cemented short Exeter stems in primary THA show acceptable survival rates at long-term follow-up. Although femoral component fracture is a rare complication of a cemented short Exeter stem, orthopaedic surgeons should be aware of its incidence and possible risk factors

The early revision rate in elective Total Hip Arthroplasty (THA) three years after surgery in elderly patients over 80 years is significantly lower for cemented stems in the German Arthroplasty Register (EPRD): cemented 3,1% (3.0 – 3.2) vs. uncemented 4.2% (4.1 – 4.3; p < 0.001). However, the mortality rate in elderly patients is elevated for cemented fixation. This study presents a detailed analysis of the influence of stem type and fixation on revision and mortality rate in this patient cohort. Elective primary THA cases for primary Coxarthrosis using uncemented cups from the EPRD data base were analysed (n. 0. = 37,183). Four stem type groups were compared: cementless, cementless with collar, cementless short, and cemented. Stems with at least 300 cases at risk three years after surgery were analysed individually. The reference stem was determined as the stem with the lowest revision rate and at least 1000 cases under surveillance 3 years after surgery (n. 3. = 28,637). The revision rate for cemented stems (2.5% [2.2–1.81] was lower than for uncemented (4.5% [4.2–4.9]; p<0.001) and uncemented short stems (4.2% [3.1–5.7]; p=0.002). The revision rate of uncemented collared stems (2.3% [1.5–3.6]) was similar to cemented stems (p=0.89) and lower than for uncemented stems (p=0.02). One year mortality showed no sig. differences between the groups (p>0.17): cemented 3.2% [2.9–3.6], uncemented 3.4% [3.1–3.7], uncemented short 3.5% [2.5–4.9], uncemented collar 2.0% [1.2–3.2]. “Cementless” and “cementless short” stems should not be used in patients over 80 years due to the higher revision risk. If cementing should be avoided, “cementless collared” stems seem to be a good alternative combined with a tendency for a lower one year mortality rate

The Lubinus SP II is an anatomical femoral stem with high survivorship levels notably described in the Swedish Arthroplasty Register. As the clinical and economic burden of revision total hip arthroplasty (THA) and periprosthetic fracture (PPF) continues to increase, it has been suggested that use of anatomical stems may facilitate more uniform cement mantles and improve implant survival. The primary aim of this study was to determine the long-term survivorship and PPF rate of the Lubinus SP II 150mm stem in a single UK centre. Between January 2007 and April 2012, 1000 consecutive THAs were performed using the Lubinus SP II femoral stem in our institution. Patient demographics and operative details were collected in a prospective arthroplasty database. Patient records and national radiographic archives were then reviewed at a mean of 12.3 years (SD 1.3) following surgery to identify occurrence of subsequent revision surgery, dislocation or periprosthetic fracture. Mean patient age at surgery was 69.3 years (SD 10.1, 24–93 years). There were 634 women (63%). Osteoarthritis was the operative indication in 974 patients (97%). There were 13 revisions in total (4 for recurrent dislocation, 3 for infection, 6 for acetabular loosening) and 16 dislocations (1.6%). Stem survivorship at 10 years was 99.6% (95 % confidence interval [CI], 99.5%–99.7%) and at 15 years was 98.8% (98.7%–98.9%). The 15-year stem survival for aseptic loosening was 100%. Analysis of all cause THA failure demonstrated a survivorship of 99.1% (99.0%–99.3%) at 10 years and 98.2% (98.1%–98.3%) at 15 years. There were 4 periprosthetic fractures in total (0.4%) at mean 12.3 year follow-up. The Lubinus SP II stem demonstrated excellent survivorship, low dislocation rates and negligible PPF rates up to 15 years following primary THA. Use of anatomical stems such as the Lubinus SPII would appear to be a wise clinical and economic investment for patients and healthcare systems alike

Aims. To compare the functional outcome, health-related quality of life (HRQoL), and satisfaction of patients who underwent primary total hip arthroplasty (THA) and a single debridement, antibiotics and implant retention (DAIR) procedure for deep infection, using either the transgluteal or the posterior surgical approach for both procedures. Methods. The study was registered at clinicaltrials.gov (ID: NCT03161990) on 15 May 2017. Patients treated with a single DAIR procedure for deep infection through the same operative approach as their primary THA (either the transgluteal or the posterior approach) were identified in the Norwegian Arthroplasty Register and given a questionnaire. Median follow-up after DAIR by questionnaire was 5.5 years in the transgluteal group (n = 87) and 2.5 years in the posterior approach group (n = 102). Results. Patients in the posterior approach group were less likely to limp after the DAIR procedure (17% vs 36% limped all the time; p = 0.005), had a higher mean Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function score (80 vs 71; p = 0.013), and were more likely to achieve a patient acceptable symptom state for the WOMAC function score (76% vs 55%; p = 0.002). In a multivariable analysis, the point estimate for the increase in WOMAC function score using the posterior approach was 10.2 (95% CI 3.1 to 17.2; p = 0.005), which is above the minimal clinically important improvement. The patients in the posterior approach group also reported better mean HRQoL scores and were more likely to be satisfied with their hip arthroplasty (77% vs 55%; p = 0.001). Conclusion. In patients treated with a single, successful DAIR procedure for deep infection of a primary THA, the use of the posterior approach in both primary surgery and DAIR was associated with less limping, better functional outcome, better HRQoL, and higher patient satisfaction compared with cases where both were performed using the transgluteal approach. The observed differences in functional outcome and patient satisfaction were clinically relevant. Cite this article: Bone Joint J 2020;102-B(12):1662–1669

Aims. Periprosthetic femoral fractures (PPF) are a serious complication of total hip arthroplasty (THA) and are becoming an increasingly common indication for revision arthroplasty with the ageing population. This study aimed to identify potential risk factors for PPF based on an analysis of registry data. Methods. Cases recorded with PPF as the primary indication for revision arthroplasty in the German Arthroplasty Registry (Endoprothesenregister Deutschland (EPRD)), as well as those classified as having a PPF according to the International Classification of Diseases (ICD) codes in patients’ insurance records were identified from the complete datasets of 249,639 registered primary hip arthroplasties in the EPRD and included in the analysis. Results. The incidence of PPFs was higher (24.6%; 1,483) than reported in EPRD annual reports listing PPF as the main reason for revision (10.9%; 654). The majority of fractures occurred intraoperatively and were directly related to the implantation process. Patients who were elderly, female, or had comorbidities were at higher risk of PPFs (p < 0.001). German hospitals with a surgical volume of < 300 primary procedures per year had a higher rate of PPFs (p < 0.001). The use of cemented and collared prostheses had a lower fracture risk PPF compared to uncemented and collarless components, respectively (both p < 0.001). Collared prostheses reduced the risk of PPF irrespective of the fixation method and hospital’s surgical volume. Conclusion. The high proportion of intraoperative fractures emphasises the need to improve surgeon training and surgical technique. Registry data should be interpreted with caution because of potential differences in coding standards between institutions. Cite this article: Bone Joint J 2021;103-B(4):650–658

Special acetabular polyethylene (PE) liners are intended to increase the stability of the artificial hip joint, yet registry studies on them are limited. The pupose of this study was to investigate differences in revision rates for mechanical complications in primary cementless total hip arthroplasty (THA) with standard and special PE acetabular liners in patients with ostheoarthritis. Data from the German Arthroplasty Registry (EPRD) between 2012 until 2020 were analysed. Patients with diagnosed ostheoarthritis of the hip without relevant prior surgeries, who received a primary cementless THA with a ceramic/PE bearing articulation were included. Cumulative incidences of revision for mechanical complications for Standard and 4 special PE liners (Lipped, Increased Offset, Angulated, Angulated|Increased Offset) were determined using the Kaplan-Meier Estimator. Confounding factors were investigated with a Cox proportional-hazards model. In total 151.104 cases were included. 7-year unadjusted revision-free survival for mechanical complications compared to Standard liners (97.7%) was lower for Angulated (97.4%), Lipped (97.2%) and Angulated|Increased Offset liners (94.7%), but higher for Increased Offset liners (98.1%). Risk of revision for mechanical complications was not significantly different between Standard, Lipped and Angulated liners. Increased Offset liners (HR=0.68; 95% CI=0.5–0.92) reduced, while Angulated|Increased Offset liners (HR= 1.81; 95% CI=1.38–2.36) increased the risk. Higher age at admission and an Elixhauser comorbidity index greater zero increased the risk, whereas a larger liner share slightly reduced the risk. Only the use of Increased Offset liners reduced the risk of revision for mechanical complications compared to Standard liners — other special liners did not

Dislocation after total hip arthroplasty in individuals treated for acute hip fracture is up to 10 times more frequent than in elective patients. Whilst approach plays a role, the effect of head sizes in conventional THA and dual mobility cups (DMC) is less studied in fracture cases. The total dislocation rate at 1-year and 3-year revision rates were recorded in this observational study on 8,031 patients with acute hip fracture, treated with a THA 2005–2014. Swedish Arthroplasty Register data were linked with the National Patient Register. Cox multivariable regression models were fitted to calculate adjusted hazard ratios stratified by approach and head size. The cumulative risk of dislocation during year 1 was 2.7% (95% CI 2.2–3.2) with lateral approach and 8.3% (7.3–9.3) with posterior approach (KM estimates). In the posterior approach group DMC was associated with a lower risk of dislocation compared to cTHA=32mm (HR=0.21; 0.07–0.68), whilst a head size <32mm carried a higher risk (HR=1.47; 1.10–1.98). These differences were no longer visible when revision in general was used as outcome. Neither of the implant designs influenced the dislocation risk when direct lateral approach was used. Male gender and severe comorbidity increased the risk. DMC with lateral approach was associated with a reduced risk of revision in general (HR=0.36; 0.13–0.99). Head size did not influence the revision risk. When aiming to reduce the risk of any dislocation, lateral approach – regardless of cup/head design – is referable. If, for any reason, posterior approach is used, DMC is associated with the lowest risk of dislocation. This is not reflected in analysing revision in general as outcome. An interpretation could be that there are different thresholds for dislocation prompting revision