To analyze the evolution of “Tsukayama type IV” infections (unexpected positive intraoperative cultures in hip arthroplasty -THA- exchange because of supposedly mechanical failure) treated with an extended protocol of combined oral antibiotics. Prospective cohort: 14 patients, 66.9+/−10.9 years (40–85), 11 males (78.6%). Eleven suffered isolated cup exchange: 6/14 first cup-exchange, 4/14 second (one with a 1st Slooff impaction-grafting reconstruction and 2 with a 2nd Slooff reconstruction), 1/14 third cup-exchange. Two were operated of isolated stem exchange. One patient received a complete exchange. Cultures identified 10 epidermidis (5 methicillin-resistant -MR-), 4 aureus (3 MR), 1 Propionibacterium, 1 Enterococcus, 1 Escherichia, 1 Streptococcus, 1 Corynebacterium, and 1 Ruminococcus. Patients received 2 oral combined intracellular and biofilm-effective antibiotics for 6 months: ciprofloxacin (8 patients), rifampin (6), amoxicillin-clavulanic (3), levofloxacin (2), clindamycin (3), trimethoprim-sulfamethoxazole (2), fosfomicin (2). Follow-up: 4.5+/−4.3 years (1–14). Healing: absence of clinical, serological and radiographic signs of infection along all followup. Infection reappeared in 1/14 patients (7.1%) with pain, distance limitation and elevated ESR&CRP; patient rejected surgery and was treated with a 2nd cycle of oral antibiotics, disappearing symptoms and serological abnormality along the following 7 years. The other 13 cases maintained normal ESR&CRP along follow-up. At the end of follow-up, 4/14 hips remain asymptomatic and with no limitation of function, 11/14 present no pain, 10/14 walk over 1Km without support, 1/11 uses a cane, 1/14 two crutches, and 2/14 a walker. In conclusión, oral combined antibiotics may be a useful alternative therapy for Tsukayama type IV hip arthroplasty infections

Aims. A typical pattern of blood loss associated with total hip arthroplasty (THA) is 200 ml intraoperatively and 1.3 l in the first 48 postoperative hours. Tranexamic acid (TXA) is most commonly given as a single preoperative dose only and is often withheld from patients with a history of thromboembolic disease as they are perceived to be “high-risk” with respect to postoperative venous thromboembolism (VTE). The TRanexamic ACid for 24 hours trial (TRAC-24) aimed to identify if an additional 24-hour postoperative TXA regime could further reduce blood loss beyond a once-only dose at the time of surgery, without excluding these high-risk patients. Methods. TRAC-24 was a prospective, phase IV, single centre, open label, parallel group, randomized controlled trial (RCT) involving patients undergoing primary unilateral elective THA. The primary outcome measure was the indirect calculated blood loss (IBL) at 48 hours. The patients were randomized into three groups. Group 1 received 1 g intravenous (IV) TXA at the time of surgery and an additional oral regime for 24 hours postoperatively, group 2 only received the intraoperative dose, and group 3 did not receive any TXA. Results. A total of 534 patients were randomized, with 233 in group 1, 235 in group 2, and 66 in group 3; 92 patients (17.2%) were considered high-risk. The mean IBL did not differ significantly between the two intervention groups (848.4 ml (SD 463.8) for group 1, and 843.7 ml (SD 478.7) for group 2; mean difference -4.7 ml (95% confidence interval -82.9 to 92.3); p = 0.916). No differences in mortality or incidence of VTE were observed between any group. Conclusion. The addition of oral TXA for 24 hours postoperatively does not reduce blood loss beyond that achieved with a single 1 g IV perioperative dose alone. There may be a clinically relevant difference in patients with a normal BMI, which warrants further investigation. Critically, there were no safety issues in patients with a history of thromboembolic, cardiovascular, or cerebrovascular disease. Cite this article: Bone Joint J 2021;103-B(7):1197–1205

Background. 91% of blood loss in Total Hip Replacement (THR) occurs in the period after skin closure and the first 24 post-operative hours. TRAC-24 was established to identify if an additional 24-hour post-operative oral regime of Tranexamic acid (TXA) is superior to a once-only intravenous dose at surgery. Methods. This was a prospective, phase IV, single centered, open label, parallel group controlled trial on patients undergoing primary elective THR. A history of thromboembolic or cardiovascular disease were not exclusion criteria. The primary outcome was indirect calculated blood loss at 48 hours (IBL). 534 patients were randomized on a 2:2:1 ratio over three different groups. Group 1 received an intravenous dose of TXA at the time of surgery and an additional 24-hour post-operative oral regime, Group 2 only received the intra-operative dose and Group 3 did not receive any TXA. Results. 233, 235 and 66 patients were recruited to groups 1,2 and 3. All groups had comparable baseline characteristics. 3.2% of all patients had previous thromboembolism and 5.4% had previous cardiac stenting. Group 3 mean (SD) IBL was 1371 (630) ml whereas group 1 and 2 combined had a mean (SD) IBL of 846 (471), p<0.001. There was no overall difference in IBL between group 1 and group 2, but subgroup analysis observed 12% less blood loss in group 1 than group 2 in the 36 patients weighing >100kg. No differences in mortality or thromboembolic events were observed in any group. Conclusion. The use of a single, intravenous, peroperative, 1-gram dose of Tranexamic acid decreased the total blood loss associated with THA by 38%. The addition of another 24-hours oral tranexamic acid did not provide additional benefit but further study on the effect of patient weight is required. Tranexamic acid is safe in patients with history of thromboembolic and cardiovascular disease

The systemic use of steroids and habitual alcohol intake are two major causative factors in the development of idiopathic osteonecrosis of the femoral head (ONFH). To examine any interaction between oral corticosteroid use and alcohol intake on the risk of ONFH, we conducted a hospital-based case-control study of 71 cases with ONFH (mean age 45 years (20 to 79)) and 227 matched controls (mean age 47 years (18 to 79)). Alcohol intake was positively associated with ONFH among all subjects: the adjusted odds ratio (OR) of subjects with ≥ 3032 drink-years was 3.93 (95% confidence interval (CI) 1.18 to 13.1) compared with never-drinkers. When stratified by steroid use, the OR of such drinkers was 11.1 (95% CI 1.30 to 95.5) among those who had never used steroids, but 1.10 (95% CI 0.21 to 4.79) among those who had. When we assessed any interaction based on a two-by-two table of alcohol and steroid use, the OR of those non-drinkers who did use steroids was markedly elevated (OR 31.5) compared with users of neither. However, no further increase in OR was noted for the effect of using both (OR 31.6). We detected neither a multiplicative nor an additive interaction (p for multiplicative interaction 0.19; synergy index 0.95), suggesting that the added effect of alcohol may be trivial compared with the overwhelming effect of steroids in the development of ONFH. Cite this article: Bone Joint J 2013;95-B:320–5

Background. Few studies have compared aspirin with DOACs (direct oral anticoagulants = direct thrombin inhibitors and factor Xa inhibitors) for venous thromboembolism (VTE) prophylaxis following total hip and knee replacement (THR and TKR). We assessed the efficacy and safety of aspirin compared with DOACs for VTE prophylaxis following THR and TKR using the world's largest joint replacement registry. Methods. We studied the National Joint Registry linked to English hospital inpatient episodes for 218,650 THR and TKR patients. Patients receiving aspirin were matched separately to (1) direct thrombin inhibitors, and (2) factor Xa inhibitors using propensity scores. Outcomes assessed at 90 days included VTE, length of stay, and adverse events. Results. Following THR, the risk of VTE was significantly lower in patients receiving direct thrombin inhibitors (0.44%; odds ratio (OR)=0.69, 95% confidence interval (CI)=0.55–0.87, p=0.002) and factor Xa inhibitors (0.37%; OR=0.63, CI=0.47–0.85, p=0.003) compared with aspirin (0.63%). Following THR, direct thrombin inhibitors (coefficient=−0.37, CI=−0.43 to −0.31, p<0.001) and factor Xa inhibitors (coefficient=−0.80, CI=−0.87 to −0.74, p<0.001) reduced length of stay compared with aspirin. Similar findings for both outcomes were observed following TKR. Compared with aspirin, DOACs did not increase the risk of short-term revision surgery; reoperation; major haemorrhage; wound disruption; surgical site infection; and mortality. Conclusions. Following THR and TKR, the risk of VTE was lower in patients receiving DOACs compared with aspirin. DOACs were associated with a reduced length of stay, and DOACs did not increase the risk of further surgery, wound problems, bleeding complications, or mortality compared with aspirin

Extensive and severe bone loss of the femur may be a result of a failed total hip arthroplasty (THA) or total knee arthroplasty (TKA) with multiple revision surgeries which may be caused by factors such as infection, periprosthetic fracture or osteolysis. The aim of this study was to assess outcomes of using the “Push-Through Total Femoral Prosthesis” (PTTF) for revision of a total hip replacement with extreme bone loss.

Fourteen patients who had extensive bone defects of the femur due to failed THR's and were treated with PTTF between 2012 and 2020 were included in this study. Primary functional outcomes were assessed using Harris Hip Score (HHS), Toronto Extremity Salvage Score (TESS) and Musculoskeletal Tumor Society (MSTS) scores. Range of motion, complications, and ambulatory status were also recorded to assess secondary outcomes.

Two of 14 patients underwent surgery with PTTF for both knee and hip arthroplasty revision. The mean time between index surgery and PTTF was 15 years (3 to 32 yrs.). Acetabular components were revised in six of 14 patients. After a mean follow-up of 5.9 years, hip dislocations occurred in 3 patients. All dislocated hips were in patients with retained non-constrained acetabular bearings. Patient satisfaction was high (MSTS: 67%, HHS: 61.2%, TESS 64.6%) despite a high re-operation rate and minor postoperative problems.

PTTF is a unique alternative that may be considered for a failed THA revision procedure in patients with an extreme femoral bone defect. Patients are able to ambulate pain free relatively well. Routine usage of constrained liners should be considered to avoid hip dislocation which was our main problem following the procedure.

Majority of ultra-high molecular weight polyethylene (UHMWPE) medical devices used in total joint arthroplasty are crosslinked using gamma radiation to improve wear resistance. Alternative methods of crosslinking are urgently needed to replace gamma radiation due to rapid decline in its supply. Peroxide crosslinking is a candidate method with widespread industrial applications. Oxidative stability and biocompatibility, which are critical requirements for medical device applications, can be achieved using vitamin-E as an additive and by removing peroxide by-products through high temperature melting, respectively. We investigated compression molded UHMWPE/vitamin-E/di-cumyl peroxide blends followed by high-temperature melting in inert gas as a material candidate for tibial knee inserts. Wear resistance increased and mechanical properties remained largely unchanged. Oxidation induction time was higher than most of the other clinically available formulations. The material passed the local-end point biocompatibility tests per ISO 10993. Compounds found in exhaustive extraction were of no concern with margin-of-safety values well above the accepted level, indicating a desirable toxicological risk profile. Peroxide crosslinked, vitamin-E stabilized, and high temperature melted UHMWPE has recently been cleared for clinical use in tibial knee inserts. With all the salient characteristics needed in a material that can provide superior long-term performance in total joint patients, peroxide crosslinking can replace gamma radiation crosslinking of UHMWPE for use in all total joint replacement implant including acetabular liners.

Tranexamic Acid (TXA) is now commonly used in major surgical operations including orthopaedics. The TRAC-24 randomised control trial aimed to assess if an additional 24 hours of TXA post – operatively in primary total hip (THA) and total knee arthroplasty (TKA) reduced blood loss. Contrary to other orthopaedic studies to date this trial included high risk patients. This paper presents the results of a cost analysis undertaken alongside this RTC. TRAC-24 was a prospective randomised controlled trial on patients undergoing TKA and THA. Three groups were included, Group 1 received 1 g intravenous (IV) TXA perioperatively and an additional 24-hour post-operative oral regime, group 2 received only the perioperative dose and group 3 did not receive TXA. Cost analysis was performed out to day 90. Group 1 was associated with the lowest mean total costs, followed by group 2 and then group 3. The difference between groups 1 and 3 −£797.77 (95% CI −1478.22, −117.32) were statistically significant. Extended oral dosing reduced costs for patients undergoing THA but not TKA. The reduced costs in groups 1 and 2 resulted from reduced length of stay, readmission rates, Accident and Emergency (A&E) attendances and blood transfusions. This study demonstrated significant cost savings when using TXA in primary THA or TKA. Extended oral dosing reduced costs further in THA but not TKA

Preoperative anaemia and intraoperative blood loss result in ∼90% of individuals being anaemic following hip and knee arthroplasty. Reducing blood loss offers the opportunity to improve outcomes and reduce the risk of transfusion and costs. This review's aim was to determine the effectiveness of drugs for preventing blood loss, and identify optimal dose, route, and timing of administration. Cochrane network meta-analysis of randomised controlled trials was conducted. Inclusion criteria: adults undergoing primary or revision elective hip or knee arthroplasty. Drugs studied: tranexamic acid (TXA), aprotinin, epsilon-aminocaproic acid, desmopressin, factor VIIa and XIII, fibrinogen, fibrin sealants, and non-fibrin sealants. Primary outcomes: need for allogenic blood transfusion, all• cause mortality (within 30 days). Secondary outcomes: mean number of transfusion episodes, re-operation, length of hospital stay and adverse events (DVT, PE, CVA, MI). 102 studies with 8418 participants. Trials included more women (63%). 47 studies (4398 participants) were included within the blood transfusion NMA. TXA given intra-articularly and orally at a total dose of greater than 3g pre-incision, intraoperatively and postoperatively ranked the highest, with anticipated absolute effect of 147 fewer transfusions per 1000 (53% chance ranking 1st) (relative risk(RR) 0.02, 95% credible interval(CrI) 0–0.31); moderate-certainty). Aprotinin (RR 0.59, 95%:CrI 0.36–0.86; low certainty evidence), fibrin (RR 0.86, CrI 0.25–2.93; very-low certainty) and EACA (RR 0.60, 95%:CrI 0.29–1.27; very-low certainty) were not shown to be as effective as TXA. TXA was the most effective drug for preventing bleeding in lower limb arthroplasty. Aprotinin and EACA were not as effective. Currently, the optimal dose, route and timing of administration of TXA is unclear. However, TXA given at higher doses and via mixed routes ranked higher in the treatment hierarchy. Oral TXA may be as effective as intavenous. There was no evidence of harm associated with higher doses of TXA

High doses of intra-articular (IA) antibiotics has been shown to effectively achieve a minimal biofilm eradication concentration which could mitigate the need for removal of infected but well-ingrown cementless components of a total hip arthroplasty (THA). However, there are concerns that percutaneous catheters could lead to multi-resistance or multi-organism peri-prosthetic joint infections (PJI) following single stage THA revisions for PJI. Eighteen single-stage revision procedures were performed for acute (N=9) or chronic (N=9) PJI following a primary (N=12) or revision (N=6) cementless THA. Modular and loosened components were replaced. All well ingrown components were retained. Two Hickmann catheters were placed in the joint space. Along with intravenous antibiotics, IA antibiotics were injected twice a day for two weeks, followed by 3 months of oral antibiotics. Per-operative cultures demonstrated 4 multi-bacterial PJIs. None of the patients developed post-operatively an AB related renal or systemic dysfunction. At a mean follow-up of 38 months [range, 8–72] all patients had normal erythrocyte sedimentation rate and white blood cell count. Four had a slightly elevated C-reactive protein but were completely symptom free and did not show any sign of loosening at a mean of 27 months [range, 16–59]. Addition of high doses of IA antibiotics following single-stage revision for PJI in cementless THA, is an effective and safe treatment option that allows for retention of well-ingrown components. We found no evidence for residual implant infection or catheter induced multi-resistance. Total hip arthroplasty, revision surgery, Periprosthetic Joint Infection, Intra-articular antibiotics. Level 4 (Case series)

Introduction

Ultra-high molecular weight polyethylene (UHMWPE) can provide local sustained delivery of therapeutics^1,2. For example, it can deliver analgesics to address post-arthroplasty pain². Given that several analgesics, such as bupivacaine (anesthetic) and tolfenamic acid (NSAID), were shown to possess antibacterial activity against Staphylococci, we hypothesize that analgesic-loaded UHMWPE can also yield antimicrobial effects, preventing the development of periprosthetic joint infections.

Constrained acetabular inserts provide a solution for both complex primary and revision hip arthroplasty, but there have been ongoing concerns for high risk of failure and their longevity. The Stryker® Trident acetabular insert is pre-assembled with its constrained ring. We believe this to be the largest series of constrained acetabular inserts with a minimum of 5 year follow-up. We retrospectively reviewed all Stryker® Trident ‘All-Poly’ constrained acetabular inserts cemented into bone in our unit between 2008 and 2016. We collated demographic details and reviewed all patients’ radiographs and clinical notes. Indications for surgery, latest Oxford Hip Scores (OHS) and clinical and radiographic complications were identified. 117 consecutive Stryker® Trident ‘All-Poly’ constrained inserts were cemented into bone in 115 patients during the study period with a mean age of 80 (47–97). Most common indications for surgery were recurrent dislocation (47), complex primary arthroplasty (23), revision arthroplasty (19) and failed hemiarthroplasty (12). 41 patients required revision of the acetabular component only. Follow-up was a minimum of 5 years (mean 8.6, range 5–13). There were three 30-day mortalities and six 1-year mortalities. The mean latest OHS was 37 (24–45). Four cups failed in three patients, one at the cement-bone interface, two at the cement-prosthesis interface and one at the bipolar interface. These were treated conservatively in three patient and with excision arthroplasty in one patient. There were four peri-prosthetic fractures, one Vancouver C distal femur fracture treated conservatively and three Vancouver B1 fractures, two treated conservatively and one treated with open reduction internal fixation. There was breakage of one constrained ring with no adverse effects and one superficial wound infection requiring oral antibiotics only. This series demonstrated that despite the elderly and complex nature of these patients’ clinical situations, constrained acetabular inserts offer a useful and pragmatic solution, with relatively low complications, including in our series a cup failure rate of 3% and peri-prosthetic fracture rate of 3%

Background. The purpose of this multicenter, randomized clinical trial was to determine the optimal dosing regimen of tranexamic acid (TXA) to minimize perioperative blood loss for revision total hip arthroplasty (THA). Methods. Six centers prospectively randomized 155 revisions to one of four regimens: 1g of intravenous (IV) TXA prior to incision, a double dose regimen of 1g IV TXA prior to incision and 1g IV TXA during wound closure, a combination of 1g IV TXA prior to incision and 1g intraoperative topical TXA, or three doses of 1950mg oral TXA administered 2 hours preoperatively, 6 hours postoperatively, and on the morning of postoperative day one. Randomization was based upon revision subgroups to ensure equivalent group distribution, including: femur only, acetabulum only, both component, explant/spacer, and second stage reimplantation. Patients undergoing an isolated modular exchange were excluded. An a priori power analysis (alpha = 0.05; beta = 0.80) determined 40 patients per group were required to identify a 1g/dL difference in postoperative hemoglobin reduction between groups. Per-protocol analysis involved an analysis of variance, Fisher's exact tests, and two one-sided t-tests for equivalence. Results. Demographic and surgical variables were equivalent between groups. No significant differences were found between TXA regimens when evaluating reduction in hemoglobin (single IV = 3.6 g/dL, double IV = 3.6 g/dL, combined = 3.4 g/dL, and oral = 3.6 g/dL; p = 0.87), calculated blood loss (p = 0.67), or transfusion rates (single IV = 14%, double IV = 20%, combined = 17%, oral = 21%; p = 0.85). Equivalence testing revealed all possible pairings were statistically equivalent, assuming greater than a 1g/dL difference in hemoglobin reduction as clinically relevant. Conclusions. All TXA regimens tested had equivalent blood-sparing properties in the setting of revision THA. Surgeons should consider the lowest effective dose and the most economical regimen. For any tables or figures, please contact the authors directly

To compare the incidence of Bone Cement Implantation Syndrome (BCIS), perioperative thromboembolic events and mortality in patients with a femoral neck fracture (FNF) treated with a hybrid total hip arthroplasty (THA) without intraoperative unfractioned heparin (UFH) (control) versus a group of patients who received intraoperative UFH before femoral cementation. We retrospectively reviewed 273 patients who underwent hybrid THA due to a FNF between 2015 and 2020. We compared a group of 139 patients without intraoperative administration of UFH (group A) with 134 patients who underwent THA with intraoperative administration of 10 UI/kg UFH (group B). UFH indication was dependent on surgeon´s preference. We assessed the advent of BCIS and 30-day thromboembolic events, as well as 90-day and 1-year mortality. BCIS was observed in 51 cases (18%), defined as Grade 1 (O2% < 94% or fall in systolic blood pressure of 20% to 40%) in 37 cases (13%) and Grade 2 (O2% < 88% or fall in systolic blood pressure of > 40%) in 14 cases (5%). Forty-seven BCIS (35%) were observed in the group that received UFH and 4 BCIS (3%) in the control group (p <0.001). Multivariate regression model showed that intraoperative UFH (OR=18, CI95% 6–52) and consumption of oral anticoagulants (OR=3.3, CI95% 1–10) had an increased risk of developing BCIS. Five patients developed a pulmonary embolism in the UFH group while 2 patients presented this complication in the non UFH group (p=0.231). Mortality was 1% for both groups at 90 days PO (p= 0.98), 2% at 1 year for group A and 3% for group B (p =0.38). BCIS in our series was 18%. We found a paradoxically 17-fold significant increase of BCIS with the use of UFH. Heparin did not prevent BCIS, thromboembolic events and mortality in this group of patients

Considerable debate exists regarding which agent(s) should be preferred for venous thromboembolism (VTE) chemical prophylaxis following joint replacement. We assessed the practice of surgeons regarding VTE chemical prophylaxis for primary THR and TKR, pre and post issuing of updated NICE guidance in 2018. A survey, circulated through the British Hip Society and regional trainee networks/collaboratives, was completed by 306 UK surgeons at 187 units. VTE chemical prophylaxis prescribing patterns for surgeons carrying out primary THR (n=258) and TKR (n=253) in low-risk patients were assessed post publication of 2018 NICE recommendations. Prescribing patterns before and after the NICE publication were subsequently explored. Questions were also asked about surgeon equipoise for participation in future RCTs. Following the new guidance, 34% (n=87) used low-molecular weight heparin (LMWH) alone, 33% (n=85) aspirin (commonly preceded by LMWH), and 31% (n=81) direct oral anticoagulants (DOACs: with/without preceding LMWH) for THR. For TKR, 42% (n=105) used aspirin (usually monotherapy), 31% (n=78) LMWH alone, and 27% (n=68) DOAC (with/without preceding LMWH). NICE guidance changed the practice of 34% of hip and 41% of knee surgeons, with significantly increased use of aspirin preceded by LMWH for THR (before=25% vs. after=73%;p<0.001), and aspirin for TKR (before=18% vs. after=84%;p<0.001). Significantly more regimens were NICE guidance compliant after the 2018 update for THR (before=85.7% vs. after=92.6%;p=0.011) and TKR (before=87.0% vs. after=98.8%;p<0.001). Support from surgeons for future RCTs was dependent on the clinical question, ranging from 48% participation in trials (effectiveness of aspirin vs. a DOAC) to 79% (effectiveness of 14 days LMWH vs. 28 days LMWH). Over one-third of surveyed surgeons changed their VTE chemical prophylaxis in response to 2018 NICE recommendations, with more THR and TKR surgeons now compliant with latest NICE guidance. The major change in practice was an increased use of aspirin for VTE chemical prophylaxis. Furthermore, there is an appetite amongst UK surgeons for participating in future RCTs, with a trial comparing standard versus extended duration LMWH likely feasible in current practice

The gold standard for PJI treatment comprises the use of antibiotic-loaded bone cement spacers, which are limited in their load bearing capacity[1]. Thus, developing an antibiotic-eluting UHMWPE bearing surface can improve the mechanical properties of spacers and improve the quality of life of PJI patients. In this study, we incorporated vancomycin into UHMWPE to investigate its elution characteristics, mechanical properties and its efficacy against an acute PJI in an animal model.

Vancomycin hydrochloride was incorporated into UHMWPE (2 to 14%) by blending and consolidation. We studied drug elution with blocks in PBS and UV-Vis spectroscopy at 280 nm. We determined the tensile mechanical properties and impact strength [3]. We implanted osteochondral plugs in rabbits using either control UHMWPE, bone cement (40g) containing vancomycin (1g) and tobramycin (3.6g) or vancomycin-eluting UHMWPE (n=5) plugs in the patellofemoral groove of rabbits. All rabbits received a beaded titanium rod in the tibial canal. All groups received two doses of 5×10⁷ cfu of bioluminescent S. aureus in the distal tibial canal prior to insertion of the rod and the articular space after closure of the joint capsule. No intravenous antibiotics were used. Bioluminescence signal was measured when the rabbits expired, or at 21-day post-op. Hardware, polyethylene implants, and joint tissues were sonicated to further quantify live bacteria via plate seeding.

Vancomycin elution increased with increasing drug loading. Vancomycin elution above MIC for 3 weeks and optimized mechanical properties were obtained at 6–7 wt% vancomycin loading in UHMWPE. In our lapine acute infection model using bioluminescent S. aureus, knees treated with UHMWPE without antibiotics and bone cement containing vancomycin and tobramycin had significantly higher bioluminescence compared to those treated with vancomycin-eluting UHMWPE.

These results suggest that an antibiotic-eluting UHMWPE spacer with acceptable properties as a bearing surface could be used to treat periprosthetic joint infection in lieu of bone cement spacers and this could allow safer load bearing and a higher quality of life for the patients during treatment. In addition, this presents a safer alternative in cases where the second stage surgery for the implantation of new components is hindered.

Introduction. Many pharmacologic agents have been used for venous thromboembolism (VTE) prophylaxis after elective total hip arthroplasty (THA). Rivaroxaban was the first novel oral anticoagulant approved for THA patients, but its actual efficacy and safety in clinical practice, beyond randomized trials, is unknown. Materials and Methods. This is a retrospective study, using the Truven Health MarketScan database, of anticoagulation medication prescriptions after elective THA, in both commercially insured (CI) and Medicare supplement insured (MS) patients, from 2010 to 2015. After exclusions, there were 83,179 CI and 50,534 MS patients available for analysis. There were 12,876 new users of warfarin (W) and 10,892 new users of rivaroxaban (R) in CI patients, and 7,416 new users of W and 4,739 new users of R in MS patients. We asked the following questions: (1) What were the trends and predictive factors for anticoagulant use after elective THA? (2) What was the actual clinical efficacy: frequency of deep vein thrombosis (DVT) and pulmonary embolism (PE), and frequency of adverse events within 90 days with the two most commonly used oral agents, rivaroxaban and warfarin, from June 2011 to September 2015? Data was analyzed for each anticoagulant by odds ratios using logistic regression models with stabilized inverse probability treatment weighting. Results. There was a change in use of anticoagulants after R approval. Use of W decreased from approximately 50% each in 2010 in both insurance cohorts to 10% in CI patients and 30% in MS patients in 4th quarter 2015. The use of R increased from 0 to 33% in both cohorts from 2011 to 2015. In the multivariate analysis, in CI patients, females had lower odds of getting R, and patients in Western region had higher odds of getting R; in MS patients, increasing age had reduced odds of getting rivaroxiban, but Western region and surgery in 2015 had higher odds. Patients with capitated insurance plans and renal impairment had lower odds of R initiation, but a history of cardiovascular disease or hypertension had higher odds. In 90 days after THA, patients given R had significantly lower odds ratio of both DVT and PE in both CI patients (DVT: 1.54 with W, 0.54 with R; PE: 2.12 with W, 0.73 with R) and MS patients (DVT: 3.01 W, 1.73 R; PE: 4.09 W, 1.88 R). With logistic regression analysis, users of W had significantly higher odds ratio of both DVT (CI 2.63 and MS 1.78) and PE (CI 2.60 and MS 2.09) than R. There was no significant difference in rates of bleeding between W and R, but W had higher odds ratio than R of prosthetic joint infection (PJI) in both CI (1.574) and MS (1.790) cohorts. Conclusions. There has been an increase in VTE prophylaxis with R, and a decrease in both W and LMWH use after elective THA over four years. Patient factors, insurance type, and comorbidities were associated with this change. In actual clinical efficacy, R had lower odds ratio of both DVT and PE than W, and bleeding risks were similar. The association of W with an increased odds ratio of PJI compared to R requires further study

Aims

The duration of systemic antibiotic treatment following first-stage revision surgery for periprosthetic joint infection (PJI) after total hip arthroplasty (THA) is contentious. Our philosophy is to perform an aggressive debridement, and to use a high local concentration of targeted antibiotics in cement beads and systemic prophylactic antibiotics alone. The aim of this study was to assess the success of this philosophy in the management of PJI of the hip using our two-stage protocol.

Aims

Periprosthetic joint infection (PJI) in total hip arthroplasty in the elderly may occur but has been subject to limited investigation. This study analyzed infection characteristics, surgical outcomes, and perioperative complications of octogenarians undergoing treatment for PJI in a single university-based institution.

Aims

Transfusion after primary total hip arthroplasty (THA) has become rare, and identification of causative factors allows preventive measures. The aim of this study was to determine patient-specific factors that increase the risk of needing a blood transfusion.