Introduction

Total hip arthroplasty (THA) is the only successful treatment for patients in whom the hip joint is destroyed by inflammatory arthritis. Due to the effects of both the disease and its treatment elevated rates of complications and of aseptic loosening have been described. Whether with modern uncemented hip prostheses the results can be improved is not fully known. Therefore, we decided to carry out a prospective study.

Material and methods

At the introduction of a new press-fit acetabular component a prospective study on the results of uncemented THA was started. From 1995 to 1999 85 primary THAs were carried out in 72 patients (57 women, 15 men) suffering from inflammatory arthritis. Diagnosis: RA 76, adult-onset Still 4, JIA 3, miscellaneous 2. Mean age at operation was 60 years (SD 15. 9). Clinically, the Harris Hip Score was used for evaluation. Radiographically, the Larsen classification was used and at follow-up radiolucencies and signs of migration were registered.

The implants used in this study were the EPF-PLUS® acetabular component and the SL-PLUS® femoral component (PLUS Endoprothetik AG, Rotkreuz-CH). The EPF-PLUS® acetabular component is a novel modular press-fit cup. Its shell has a triple radius profile on cross-section, thereby creating a gradual lowering of the polar part of the cup. This produces a small gap of about 2 mm. between the acetabulum and the pole of the cup. Therefore, forces are mainly transmitted to the peripheral part of the acetabulum, leading to an enhanced primary stability. Originally, the shell had a gritblasted surface for osseointegration. Since 1996, the outer surface of the cup has been coated with a ground layer of pure titanium and a superficial layer of a crystalline hydroxyapatite (Ti-HA). The gritblasted version was used in 14 hips (1995–1996), the Ti-HA coated version in 71 hips. In 68 hips the cup was implanted by press-fit fixation, in 17 screws were added.

Results

Larsen classification was as follows: 0-1: 6; 3: 17; 4: 60; 5: 2. At follow-up, 5 patients (6 THAs) were deceased. Deep infection required revision in one hip. Another revision was carried out for recurrent dislocations. One grit-blasted cup developed late subsidence and was revised almost 4 years postoperatively. One Ti-HA coated cup failed early due to severe acetabular bone loss. Finally, one femoral component developed a varus tilt and became symptomatic 2 years after implantation, requiring revision. In all 62 patients with 74 THAs in follow-up cup and stem are functioning well, both clinically and radiographically. Harris Hip Score increased from 36. 6 (SD 17. 7) to 87. 9 (SD 11. 8).

Discussion

The medium-term results of the EPF®-PLUS cup show that its primary stability is good and that, as the polar gap rapidly disappears, osseointegration is secure. Only severe acetabular deficiency appears to be a contra-indication for this implant. Also, the SL-PLUS® stem performs well in inflammatory arthritis.

In primary total hip arthroplasty (THA) for patients with Crowe II or higher classes developmental dysplasia of the hip (DDH) or rapidly destructive coxopathy (RDC), the placement of the cup can be challenging due to superior and lateral acetabular bone defects. Traditionally, bone grafts from resected femoral heads were used to fill these defects, but bulk graft poses a risk of collapse, especially in DDH with hypoplastic femoral heads or in RDC where good quality bone is scarce. Recently, porous metal augments have shown promising outcomes in revision surgeries, yet reports on their efficacy in primary THA are limited. This study retrospectively evaluated 27 patients (30 hips) who underwent primary THA using cementless cups and porous titanium acetabular augments for DDH or RDC, with follow-up periods ranging from 2 to 10 years (average 4.1 years). The cohort included 22 females (24 hips) and 5 males (6 hips), with an average age of 67 years at the time of surgery. The findings at the final follow-up showed no radiographic evidence of loosening or radiolucency around the cups and augments, indicating successful biological fixation in all cases. Clinically, there was a significant improvement in the WOMAC score from an average of 39.1±14.7 preoperatively to 5.1±6.4 postoperatively. These results suggest that the use of cementless cups and porous titanium acetabular augments in primary THA for DDH and RDC can lead to high levels of clinical improvement and reliable biological fixation, indicating their potential as a viable solution for managing challenging acetabular defects in these conditions

Arthrofibrosis is a relatively frequent complication after total knee arthroplasty. Although stiffness after total hip arthroplasty (THA), because of formation of heterotopic ossification or other causes, is not uncommon, to the authors’ best knowledge, arthrofibrosis after THA has not been described. The aim of this study is to describe the arthrofibrosis of the hip after primary total hip arthroplasty using an established clinical and histological classification of arthrofibrosis. We retrospectively examined all patients who were histologically confirmed to have arthrofibrosis after primary THA during revision surgery by examination of tissue samples in our clinic. Arthrofibrosis was diagnosed according to the histopathological SLIM-consensus classification, which defines seven different SLIM types of the periimplant synovial membrane. The SLIM type V determines the diagnosis of endoprosthesis-associated arthrofibrosis. The study population consists of 66 patients who were revised due to arthrofibrosis after primary THA. All patients had a limitation in range of motion prior to revision with a mean flexion of 90° (range from 40 to 125), mean internal rotation of 10° (range from 0 to 40) and mean external rotation of 20° (range from 0 to 50). All patients had histological SLIM type V arthrofibrosis, corresponding to endoprosthesis-associated arthrofibrosis. Histological examination revealed that seven patients (10.6%) had particle-induced and 59 patients (89.4%) had non-particle-induced arthrofibrosis. This is the first decription of endoprosthetic-associated arthrofibrosis after primary THA on the basis of a well-established histological classification. Our study results could enable new therapeutic and diagnostic opportunities in patients with such an arthrofibrosis. Surgeons should keep arthrofibrosis as a possible cause for stiffness and pain after primary total hip arthroplasty in mind. Level of evidence Diagnostic study, Level of Evidence IV. Thorsten Gehrke and Lara Althaus contributed equally to the writing of this manuscript

Literature data show varying rates of aseptic loosening of standard hemispherical cups after primary total hip arthroplasty (THA) in patients with Crowe IV developmental dysplasia of the hip (DDH). In order to improve the results regarding the frequency of aseptic loosening of the acetabular component, we decided to use custom-made acetabular implants (CMAI) in this category of patients. The aim of our study was to report outcomes after primary THA using CMAI in patients with Crowe IV DDH. We retrospectively analyzed the results of primary THA using the CMAI in 58 hips. The mean follow-up period was 5.2 years (range 4.2 – 6.3). Patients demonstrated improved functional outcomes according to the Oxford Hip Score: preoperatively 16.9 and postoperatively 38.5 (P < 0.05). Revisions were performed in 2 cases due to dislocations, in 1 case due to nonunion of the greater trochanter and in 1 case due to chronic pain syndrome caused by contact of the CMAI flange with the iliopsoas muscle. In a patient with chronic pain syndrome, during the revision, the pubic flange of the CMAI, which was in contact with the iliopsoas muscle, was removed. There were no radiological signs of loosening of the CMAI. The use of CMAI shows good results in patients with DDH. Extended capability for supplementary screw fixation is an excellent feature of such implants, allowing them to obtain reliable primary fixation. Further observation is required to assess CMAI in the long-term follow-up

Aim. Prosthetic joint infection (PJI) is a serious complication following total hip arthroplasty (THA) entailing increased mortality, decreased quality of life, and high healthcare costs. In 2009 a nationwide, multidisciplinary infection control program was launched in Sweden, PRISS, which aimed to reduce the PJI burden by 50%. The primary aim was to investigate whether the PRISS project reduced PJI incidence after primary THA; the secondary aim was to evaluate other possible benefits of PRISS, such as shorter time to diagnosis. Method. We obtained data on patients undergoing primary THA in Sweden (n = 45,723 patients, 49,946 THAs), 2012–2014. Using personal identity numbers, this cohort was matched with the Swedish Prescribed Drug Registry. Medical records of patients with ≥4 weeks antibiotic consumption were reviewed to verify PJI diagnosis (n = 2240, 2569 THAs). Results. The cumulative incidence of PJI following the PRISS project was 1.2% [95% CI 1.1–1.3] as compared to 0.9% [95% CI 0.8–1.0] before. Cox regression models for the PJI incidence post PRISS indicates there were no statistical significance difference versus pre PRISS (HR 1.1 [95% CI 0.9–1.3]. There were similar time to PJI diagnosis after the PRISS project 24 vs 23 days (p=0.5). Conclusions. Despite the comprehensive nationwide PRISS project, Swedish PJI incidence was higher after the project and time to diagnosis remained unchanged. Factors contributing to PJI, such as increasing obesity, higher ASA class, and more fractures as indications, explain the PJI increase among primary THA patients

Periprosthetic femur fracture (PFF) is a major complication following total hip arthroplasty (THA) that carries significant morbidity, mortality, and economic burden. Currently, uncemented stems are highly preferred in primary THA, but have been associated with higher risk of PFF compared to cemented stems. The use of collared stems in uncemented primary THA has shown promise in reducing PFF rates postoperatively. This retrospective study included 2,294 uncemented primary THAs using the posterior approach performed by two attending surgeons from January 2016 to December 2022. Both surgeons switched from a collarless femoral stem design to a collared design in May 2020. Data was collected regarding stem design, frequency of PFF, and requirement for revision surgery. Periprosthetic fractures were identified and confirmed using medical records and/or radiographic imaging. Fracture rates and percentages between collared and collarless stems were then analyzed. A Fisher's Exact Test was performed to determine if there was a significant association between collared and collarless stem use on PFF rates. A total of 2,294 uncemented primary THAs performed by 2 surgeons were eligible for analysis. 903 (39.4%) patients received a collared stem, and 1,391 (60.6%) patients received a collarless stem. In total, 14 (0.6%) PFFs occurred over the study period. There was 1 fracture (0.1%) out of 903 collared stems, and 13 fractures (0.9%) out of 1,391 collarless stems (p = 0.012). Collared stems were associated with a significant decrease in PFF rate when compared to collarless stems in uncemented primary THA. Future studies are encouraged to continue to investigate PFF and other complication rates with the use of a collared stem design

Abstract. Background. Although tantalum is a well recognised implant material used for revision arthroplasty, little is known regarding the use of the same in primary total hip arthroplasty. Methods. A literature search was performed to find all relevant clinical studies until March 2020, which then underwent a further selection criteria. The inclusion criteria was set as follows: Reporting on human patients undergoing primary total hip arthroplasty; Direct comparison between tantalum acetabular cups with conventional acetabular cups. for use in primary total hip arthroplasty; Radiological evaluation (cup migration, osteointegration); Clinical (functional scores, need for subsequent revision, patient-reported outcomes; Post-operative complications; Reporting findings in the English Language. After a thorough search a total of six studies were included in the review. The primary outcome. measures were clinical outcomes, implant migration, change in bone mineral density and rate of revision and infection. Results. Tantalum was found superior to titanium with regards to fewer radiolucencies, survivorship, osteointegration, decreased osteolysis and mechanical loosening. No significant difference in radioisometric analysis, bone mineral density or Harris Hip Score was found. Revision and infection rates were found to be significantly lower in tantalum group at 10 years from pooled data of national joint registry. Conclusion. The use of tantalum can be reserved for cases of high risk of failure or mechanical loosening, where failure of a contralateral joint occurred as it carries lower risk of failure and infection. Further studies with longer follow-up would be useful in drawing further conclusions

Detection of clinical situations are the most difficult for primary THA and factors which determine the complexity. Results of 2368 primary THA performed by one surgeon in 1923 patients with various hip pathologies from 2004 to 2016 were analyzed. The time of the surgery, the bloodloss, the features of the surgical technique, the implants used, and the incidence of complications and revisions were assessed and X-ray analysis was performed. Difficult cases of primary hip arthroplasty include severe dysplasia (types B2, C1, and C2 according to the Hartofilakidis classification), post-traumatic segmental acetabular defects and pelvic discontinuity, protrusio acetabuli, iatrogenic bone ankylosis and consequences of proximal femur fractures with significant shortening of the limb. X-ray signs of difficulty included an interruption of the Shenton line of 2 cm or more (except for acute fractures of proximal femur), the femoral neck-shaft angle less than 100°, and the horizontal distance from Kohler line to center of rotation less than 20% of the diameter of the femoral head. An additional burdening factor is the previous surgical interventions on the hip joint. The ten-year survival rate for standard cases was 94.9%, and for complex cases − 92.3%. The odds ratio development of complications in complex cases compared to standard cases is OR = 8.402 (95% CI from 4.614 to 15.300). In standard cases mean HHS increased from 42.9 points before surgery to 95.3 after surgery. In complex cases mean HHS before surgery was 38.9 and after surgery improved to 81.6 points, p <0.001. The complexity of the operation cannot be determined on the basis of only the etiological factor, it is necessary to take into account the severity of anatomical changes

Primary total hip replacement (THR) is a successful and common operation which orthopaedic trainees must demonstrate competence in prior to completion of training. This study aimed to determine the impact of operating surgeon grade and level of supervision on the incidence of 1-year patient mortality and all-cause revision following elective primary THR in a large UK training centre. National Joint Registry (NJR) data for all elective primary THR performed in a single University Teaching Hospital from 2005–2020 were used, with analysis performed on the 15-year dataset divided into 5-year temporal periods (B1 2005–2010, B2 2010–2015, B3 2015–2020). Outcome measures were mortality and revision surgery at one year, in relation to lead surgeon grade, and level of supervision for trainee-led operations. 9999 eligible primary THR were undertaken, of which 5526 (55.3%) were consultant led (CL), and 4473 (44.7%) trainees led (TL). Of TL, 2404 (53.7%) were non-consultant supervised (TU), and 2069 (46.3%) consultant supervised (TS). The incidence of 1-year patient mortality was 2.05% (n=205), and all-cause revision was 1.11% (n=111). There was no difference in 1-year mortality between TL (n=82, 1.8%) and CL (n=123, 2.2%) operations (p=0.20, OR 0.78, CI 0.55–1.10). The incidence of 1-year revision was not different for TL (n=56, 1.3%) and CL (n=55, 1.0%) operations (p=0.15, OR 1.37, CI 0.89–2.09). Overall, there was no temporal change for either outcome measure between TL or CL operations. A significant increase in revision within 1-year was observed in B3 between TU (n=17, 2.7%) compared to CL (n=17, 1.0%) operations (p=0.005, OR 2.81, CI 1.35–5.87). We found no difference in 1-year mortality or 1-year all-cause revision rate between trainee-led primary THR and consultant-led operations over the entire fifteen-year period. However, unsupervised trainee led THR in the most recent 5-year block (2015–2020) has a significantly increased risk of early revision, mainly due to instability and prosthetic joint infection. This suggests that modern surgical training is having a detrimental effect on THR patient outcomes. More research is needed to understand the reasons if this trend is to be reversed

The benefit of using acetabular screws in primary total hip arthroplasty (THA) has been questioned in recent years. The disadvantages of using screws include increased operative time, risk of injury to surrounding neurovascular structures and metal ware breakage. Recent large registry studies have reported that screws do not confer a protective effect against acetabular loosening or the presence of osteolysis. Other studies have even described an increased risk of aseptic acetabular loosening with the selective use of screws. We report findings from a multicentre cohort study. This large cohort study compared clinical outcomes between primary acetabular components that were inserted with and without screws. Independent variables included the presence (or absence) of screws, the total number of screws used and the cumulative screw length (CSL). Outcome measures included all-cause revision, acetabular component revision and acetabular component loosening. Statistical software (Stata/IC 13.1 for Mac [64-bit Intel]) was used to conduct all statistical analyses. A p-value < 0 .05 taken to be significant. There were 4,583 THAs performed in total. Screws were used in 15.9% (n=733). At a mean follow-up of 5.2 years, the all-cause revision rate in the screw cohort was 1.5% compared to 0.83% in the no screw cohort (p=0.085). There was no difference in acetabular component revision rates for screws (3/733, 0.41%) versus no screws (12/3,850, 0.31%) (p=0.439). The rate of acetabular loosening noted during the time of revision surgery was significantly higher when screws were used in the index procedure (2/733, 0.2%) compared to the no screw cohort (1/3,850, 0.02%) (p=0.017). There was no difference in outcomes when stratifying by the number of screws used or the cumulative screw length. Primary acetabular components do not require screws for fixation. All cause revision rates and acetabular component revision rates are comparable for the screw and the no screw cohorts. The rate of acetabular component loosening, as observed during revision surgery, is significantly higher when screws are used in the index total hip replacement

Total hip arthroplasty (THA) is one of the most successful and effective treatments for advanced hip osteoarthritis (OA). Over the last 5 years, Canada has seen a 17.8% increase in the number of hip replacements performed annually, and that number is expected to grow along with the aging Canadian population. However, the rise in THA surgery is associated with an increased number of patients at risk for the development of an infection involving the joint prosthesis and adjacent deep tissue – periprosthetic joint infections (PJI). Despite improved hygiene protocols and novel surgical strategies, PJI remains a serious complication. No previous population-based studies has investigated PJI risk factors using a time-to-event approach and none have focused exclusively on patients undergoing THA for primary hip OA. The purpose of this study is to determine risk factors for PJI after primary THA for OA using a large population-based database collected over 15 years. Our secondary objective is to determine the incidence of PJI, the time to PJI following primary THA, and if PJI rates have changed in the past 15 years. We performed a population-based cohort study using linked administrative databases in Ontario, Canada in accordance with RECORD and STROBE guidelines. All primary total hip replacements performed for osteoarthritis in patients aged 55 or older between January 1st 2002 – December 31st 2016 in Ontario, Canada were identified. Periprosthetic joint infection as the cause for revision surgery was identified with the International Classification of Diseases, 10th Edition (ICD-10), Clinical Modification diagnosis code T84.53 in any component of the healthcare data set. Data were obtained from the Institute for Clinical Evaluative Sciences (ICES). Demographic data and outcomes are summarized using descriptive statistics. We used a Cox proportional hazards model to analyze the effect of surgical factors and patient factors on the risk of developing PJI. Surgical factors include the approach, use of bone graft, use of cement, and the year of surgery. Patient factors include sex, age at surgery, income quintile and rurality (community vs. urban). We compared the 1,2,5 and 10 year PJI rates for patients undergoing THA each year of our cohort with the Cochran-Armitage test. Less than 0.1% of data were missing from all fields except for rurality which was lacking 0.3% of data. A total of 100,674 patients aged 55 or older received a primary total hip arthroplasty for osteoarthritis from 2002–2016. We identified 1034 cases of revision surgery for prosthetic joint infection for an overall PJI rate of 1.03%. When accounting for patients censored at final follow-up, the cumulative incidence for PJI is 1.44%. Our Cox proportional hazards model revealed that male sex, Type II diabetes mellitus, discharge to convalescent care, and having both hips replaced during one's lifetime were associated with increased risk of developing PJI following primary THA. Importantly, the time adjusted risk for PJI was equal for patients operated within the past 5 years, 6–10 years ago, or 11–15 years ago. The surgical approach, use of bone grafting or cement were not associated with increased risk of infection. PJI rates have not changed significantly over the past 15 years. One, two, five and ten-year PJI rates were similar for patients undergoing THA in all qualifying years. Analysis of a population-based cohort of 100,674 patients has shown that the risk of developing PJI following primary THA has not changed over 15 years. The surgical approach, use of bone grafting or cement were not associated with increased risk of infection. Male sex, Type II diabetes Mellitus and discharge to a rehab facility are associated with increased risk of PJI. As the risk of PJI has not changed in 15 years, an appropriately powered trial is warranted to determine interventions that can improve infection rate after THA

Aim. Two types of national registers surveil infections after primary total hip arthroplasty (THA) in Norway: The National surveillance system for surgical site infections (NOIS) that surveil all primary THAs 30 days postoperatively for surgical site infections (SSI), and the Norwegian Arthroplasty Register (NAR) that follow all THAs until any surgical reoperation/revision or the death of the patient. Since these registers report on the same THAs we assessed correspondence between and time trends for the two registers in period 2013 to 2022. All reported THAs were included. Method. The THAs were matched on a group level according to sex, age and ASA-class. In addition to descriptive statistics, adjusted Cox regression analyses were performed with adjustment for sex, age group (<45, 45-54, 55-64, 65-74, 75-84, >85 years) and ASA-class (1, 2, 3, 4 and missing). Changes in annual incidence and adjusted hazard rate (aHR) was calculated. Endpoints in the NOIS were 30-Days SSI and 30-Days reoperation for SSI. Endpoints in the NAR were 30-Days and 1-Year reoperation for periprosthetic joint infection (PJI). Results. The NOIS had registered 87,923 THAs with 1,393 (1.58%) SSIs and 765 (0.87%) reoperations for SSI within 30 postoperatively. The NAR had registered 91,194 THAs with 725 (0.80%) reoperations for infection after 30 days, and 1,019 (1.21%) reoperations for infections after one year. The distribution of sex, age and ASA-class was near identical in the two registers. There was a mean annual reduction in risk of both SSI (aHR 0.92 (95% CI 0.90-0.93)) and reoperation for SSI (0.95(0.92-0.97)) and PJI (30-Days: 0.96 (0.94-0.99), 1-Year: 0.95-0.99)) over the period 2013-2022. Conclusions. The NOIS and the NAR have excellent completeness and the registrations in both registers may be considered representative for the Norwegian population. Not all SSI are reoperated. The incidence and risk of SSI (NOIS) and reoperation for PJI (NAR) is declining and may reflect a true reduction in incidence of PJI after primary THA

The last two decades have seen remarkable technological advances in total hip arthroplasty (THA) implant design. Porous ingrowth surfaces and highly crosslinked polyethylene (HXLPE) have been expected to dramatically improve implant survivorship. The purpose of the present study was to evaluate survival of contemporary cementless acetabular components following primary THA. 16,421 primary THAs performed for osteoarthritis between 2000 and 2019 were identified from our institutional total joint registry. Patients received one of 12 contemporary cementless acetabular designs with HXLPE liners. Components were grouped based on ingrowth surface into 4 categories: porous titanium (n=10,952, mean follow-up 5 years), porous tantalum (n=1223, mean follow-up 5 years), metal mesh (n=2680, mean follow-up 6.5 years), and hydroxyapatite (HA) coated (n=1566, mean follow-up 2.4 years). Kaplan-Meier analyses were performed to assess the survivorship free of acetabular revision. A historical series of 182 Harris-Galante-1 (HG-1) acetabular components was used as reference. The 15-year survivorship free of acetabular revision was >97% for all 4 contemporary cohorts. Compared to historical control, porous titanium (HR 0.06, 95% CI 0.02–0.17, p<0.001), porous tantalum (HR 0.09, 95%CI 0.03–0.29, p<0.001), metal mesh (HR 0.11, 95%CI 0.04–0.31, p<0.001), and HA-coated (HR 0.14, 95%CI 0.04–0.48, p=0.002) ingrowth surfaces had significantly lower risk of any acetabular revision. There were 16 cases (0.1%) of acetabular aseptic loosening that occurred in 8 (0.07%) porous titanium, 5 (0.2%) metal mesh, and 3 (0.2%) HA-coated acetabular components. 7 of the 8 porous titanium aseptic loosening cases occurred in one known problematic design. There were no cases of aseptic loosening in the porous tantalum group. Modern acetabular ingrowth surfaces and HXLPE liners have improved on historical results at the mid-term. Contemporary designs have extraordinarily high revision-free survivorship, and aseptic loosening is now a rare complication. At mid-term follow-up, survivorship of contemporary uncemented acetabular components is excellent and aseptic loosening occurs in a very small minority of patients

With the introduction of highly crosslinked polyethylene (HXLPE) in total hip arthroplasty (THA), orthopaedic surgeons have moved towards using larger femoral heads at the cost of thinner liners to decrease the risk of instability. Several short and mid-term studies have shown minimal liner wear with the use HXLPE liners, but the safety of using thinner HXPLE liners to maximize femoral head size remains uncertain and concerns that this may lead to premature failure exist. Our objective was to analyze the outcomes for primary THA done with HXLPE liners in patients who have a 36-mm head or larger and a cup of 52-mm or smaller, with a minimum of 10-year follow-up. Additionally, linear and volumetric wear rates of the HXLPE were evaluated in those with a minimum of seven-year follow-up. We hypothesized that there would be minimal wear and good clinical outcome. Between 2000 and 2010, we retrospectively identified 55 patients that underwent a primary THA performed in a high-volume single tertiary referral center using HXLPE liners with 36-mm or larger heads in cups with an outer diameter of or 52-mm or smaller. Patient characteristics, implant details including liner thickness, death, complications, and all cause revisions were recorded. Patients that had a minimum radiographic follow-up of seven years were assessed radiographically for linear and volumetric wear. Wear was calculated using ROMAN, a validated open-source software by two independent researchers on anteroposterior X-rays of the pelvis. A total of 55 patients were identified and included, with a mean age of 74.8 (range 38.67 - 95.9) years and a mean BMI of 28.98 (range 18.87 - 63-68). Fifty-one (94.4%) of patients were female. Twenty-six (47.7%) patients died during the follow-up period. Three patients were revised, none for liner wear, fracture or dissociation. Twenty-two patients had a radiographic follow-up of minimum seven years (mean 9.9 years, min-max 7.5 –13.7) and were included in the long-term radiographic analysis. Liner thickness was 5.5 mm at 45 degrees in all cases but one, who had a liner thickness of 4.7mm, and all patients had a cobalt-chrome head. Cup sizes were 52mm (n=15, 68%) and 50mm (n=7, 32%). Mean linear liner wear was 0.0470 mm/year (range 0 - 0.2628 mm) and mean volumetric wear was 127.69 mm3/year (range 0 - 721.23 mm3/year). Using HXLPE liners with 36-mm heads or bigger in 52-mm cups or smaller is safe, with low rates of linear and volumetric wear in the mid to long-term follow-up. Patients did not require revision surgery for liner complications, including liner fracture, dissociation, or wear. Our results suggest that the advantages of using larger heads should outweigh the potential risks of using thin HXLPE liners

To estimate the clinical and economic burden of primary total hip arthroplasty (THA) dislocation in England. Retrospective propensity score-matched evaluation of patients with and without dislocation following primary THA using the UK Clinical Practice Research Datalink linked and Hospital Episode Statistics datasets with a 2-year follow-up. 13,044 patients with total hip replacements met the inclusion criteria (mean age 69.2, 60.9% female) of which 154 (1.18%) suffered at least one postoperative hip dislocation. The mean number of dislocations per patient was 1.44 with a maximum of 4. Approximately one-third of the patients with dislocation (32.5%) had more than one dislocation. Among patients with a hip dislocation 148 patients (96.7%) had at least one closed reduction and 20 patients (13.1%) had revision surgery. Two-year median direct medical costs were £14,748 (95% confidence interval [CI] £12,028 to £20,638) higher with vs. without dislocation (+227%). On average, patients with a dislocation had significantly greater healthcare resource utilization and significantly less improvement in EuroQol-5D (EQ-5D) index (0.24 vs. 0.45; p<0.001) and Visual Analogue Scale (VAS) (1.58 vs. 11.23; p=0.010) scores and Oxford Hip Scores (13.02 vs. 21.98; p<0.001). This is the first study to estimate the economic burden of dislocation in the UK throughout the entire patient pathway. Dislocation following total hip replacement is a costly complication, both in terms of economic costs and to the functional quality of life of the patient. Efforts to reduce the risks of dislocation should remain at the forefront of hip research

Introduction. With the widespread legalization of cannabis across the United States, well-powered studies evaluating the impact of cannabis use disorder on outcomes following primary total hip arthroplasty are warranted. Therefore, the aim of this study was to determine whether cannabis use disorder has an effect on patients who undergo primary hip arthroplasty in terms of: 1) hospital lengths of stay (LOS); 2) medical complications; 3) implant-related complications; and 4) costs of care. Methods. Using an administrative database, patients who underwent primary total hip arthroplasty and had cannabis use disorder were matched to a cohort who did not in a 1:5 ratio by age, sex, and various medical comorbidities. This yielded 44,154 patients; 7,361 who had cannabis use disorder and 36,793 who did not. Variables for analysis included postoperative LOS, 90-day medical complications, 2-year implant-related complications, and 90-day costs of care. Mann-Whitney-U tests were used to compare LOS and costs. Multivariate logistic regression analyses were used to calculate the odds ratios (ORs) of developing complications. A p-value less than 0.005 was considered statistically significant. Results. The study found that patients who had cannabis use disorder had significantly longer in-hospital LOS (4 vs. 3 days, p<0.0001) compared to the matched cohort. Additionally, study patients were found to have significantly higher incidences and odds of developing medical (11.23 vs. 4.82%; OR: 1.47, p<0.0001) and implant-related complications (18.14 vs. 8.60%; OR: 1.50, p<0.0001). Moreover, patients who had cannabis use disorder incurred significantly higher 90-day episode of care costs ($24,585.96 vs. $23,725.93, p<0.0001). Conclusions. With the growing rates of cannabis use, this study can allow orthopaedists and other healthcare professionals to educate cannabis use disorder on the possible outcomes following their total hip arthroplasty. It should be appreciated that cannabis use disorder is associated with longer hospital stays, increased complication rates, and higher costs following primary THA

Aim. To study whether revision for prosthetic joint infection (PJI) after early PJI in primary Total Hip Arthroplasty (THA) is associated with a high mortality, when compared with:. Patients, who did not undergo revision for any reason and Patients who underwent an aseptic revision. Method. This population-based cohort study was based on the Danish Hip Arthroplasty Register on primary THA performed in Denmark from 2005 to 2014. Data from the Danish Hip Arthroplasty Register were linked to microbiology databases, the National Register of Patients, and the Civil Registration System to obtain data on microbiology, comorbidity, and vital status on all patients. The mortality risk for the patients who underwent revision for PJI within 1 year from implantation of primary THA was compared with (1) the mortality risk for patients who did not undergo revision for any reason within 1 year of primary THA; and (2) the mortality risk for patients who underwent an aseptic revision. Results. A total of 68,504 primary THAs in 59,954 patients were identified, of those 445 primary THAs underwent revision for PJI, 1350 primary THAs underwent revision for other causes and the remaining 66,709 primary THAs did not undergo revision. Patients were followed from implantation of primary THA until death or 1 year of follow-up, or, in case of a revision, 1 year from the date of revision. Within 1 year of primary THA, 8% (95% CI, 6%–11%) of patients who underwent revision for PJI died. The adjusted relative mortality risk for patients with revision for PJI was 2.18 (95% CI, 1.54–3.08) compared with the patients who did not undergo revision for any cause (p < 0.001). The adjusted relative mortality risk for patients with revisions for PJI compared with patients with aseptic revision was 1.87 (9f5% CI, 1.11–3.15; p = 0.019). Patients with enterococci-infected THA had a 3.10 (95% CI, 1.66–5.81) higher mortality risk than patients infected with other bacteria (p < 0.001). Conclusions. Revision for PJI within 1 year after primary THA induces an increased mortality risk during the first year after the revision surgery. Especially enterococci-infected THA have a high motrtaly risk

Dislocation after Total Hip Arthroplasty (THA) is a frequent cause of revision and patients with intrinsic risk factors have been identified. The use of dual mobility (DM) cup has shown great efficiency in preventing dislocation, with questions regarding selective or absolute use. The aim of this study was to compare the outcome of single mobility THA (SM-THA) and DM-THA, when used for selected patients. This retrospective continuous cohort study evaluated 490 patients of whom 275 received SM-THA and 215 received DM-THA. There were 304 primary osteoarthritis (62%), 121 femoral neck fractures (24%) and 65 other indications (14%). The surgical approach was anterior (AA) in 79% and posterior (PA) in 21% of cases. In the DM-THA group, 189 patients (87%) presented at least one dislocation risk factor compared to 128 patients (46%) in the SM-THA group. The primary outcome was revision for all causes, with or without implant removal. Secondary outcomes included length of hospital stay. There was no difference in all cause revision at two years follow up with 9 procedures (3.2%) in SM-THA group and 11 in DM-THA group (5.1%) (p=0.3). There were 3 dislocations in SM-THA group (3 AA) and 3 in DM-THA group (2 PA and 1 AA) (p=0.4). The length of stay was significantly longer in DM-THA group with 7 days (2–12) compared to 4 days (1–7) in SM-THA group (p=0.001). SM-THA and DM-THA are two complementary devices in the management of patients requiring primary THA. SM-THA is a safe option for patients without dislocation risk factors, especially when using AA. The identification of such factors is important to select patients requiring DM-THA and provide reproducible outcomes in a University Hospital practice including various levels of surgeon experience

Background. Uncemented dual-tapered stems are a popular choice for primary total hip arthroplasty (THA). The purpose of this study was to examine long-term outcomes after primary THA utilizing a single dual-tapered stem. Patients and Methods. Utilizing our total joint registry, we retrospectively identified 1215 THAs (1055 patients) performed with an uncemented dual-tapered stem from 1998 to 2009. Mean age was 55 years, 70% were male, and mean BMI was 30 kg/m. 2. Mean follow-up was 10 years. Analysis included implant survivorship, clinical outcomes, and radiographic results. Results. Survivorship from stem revision for any reason was 99.0% at 5 years postoperatively and 98.4% at both 10 and 15 years. Survivorship from stem revision for aseptic loosening was 99.9% at 5-, 10-, and 15-years postoperatively. Survivorship from stem revision for periprosthetic fracture was 99.7%, 99.1%, and 98.9% at 5, 10, and 15 years postoperatively, respectively. In total, 18 (1.5%) stems underwent revision. Revisions were performed for periprosthetic fracture (10, 0.82%), infection (7, 0.58%), and aseptic loosening (1, 0.08%). Intraoperative fracture occurred in 58 (4.77%) THAs treated with cerclage wiring (52, 89.66%) or no treatment (6, 10.34%) and insertion of a standard prosthesis. At mean radiographic follow-up of 10 years, only 4 of 1084 (0.37%) stems with 1-year radiographic follow-up had any radiolucency around the proximal ongrowth coating, and only 1 (0.10%) of these had a circumferential radiolucent line (Gruen zones 1–14). Conclusions. This uncemented dual-tapered femoral stem is associated with excellent survivorship, reasonably low intraoperative fracture rate, and extremely low rates of revision for aseptic loosening, periprosthetic fracture, and infection when used for primary THA at long-term follow up. For any tables or figures, please contact the authors directly

Introduction. Patients undergoing primary total hip arthroplasty (THA) with prior lumbar spine fusion (LSF) are at high risk for instability with reported incidence of dislocation as high as 8.3%. The use of dual mobility cups in patients undergoing revision THA, another high risk group, has demonstrated decreased incidence of instability. Purpose of this study was to evaluate the risk of instability in patients undergoing primary THA with a history of prior LSF using dual mobility cups. Methods. This was a multi-center retrospective study with 93 patients undergoing primary THA using a dual mobility cup with prior history of instrumented LSF. The primary outcome investigated was instability. Secondary variables investigated included number of levels fused, approach, length of stay, and other complications. The minimum follow-up time was 1 year since the majority of dislocations occur during first year following the primary THA. Results. There were 56 females and 47 males with average age of 66 years (46–87) and average BMI of 30. Mean follow up was 31 months (range 12 – 124.2). Surgical approach included: posterior (63), direct lateral (15), anterior (11), direct superior (4). 44% had one level fusion, 29% with 2 levels, and 15% with 3 or more levels fused. There were no dislocations or infections in this study group. There was one intraoperative fracture and one DVT. Conclusions. Patients undergoing primary THA with prior LSF are a high risk group with an increased risk for instability due to the loss of normal spino-pelvic relationship. The use of dual mobility cups in a high risk group of patients in this study demonstrated excellent results with no incidence of dislocation. Despite the limitations in this study with varying approaches and multiple sites, the use of dual mobility cups to decrease the incidence of instability in patients with prior LSF appears promising. For any tables or figures, please contact the authors directly