Intra-articular Vancomycin Reduces Prosthetic Infection in Primary Hip and Knee Arthroplasty.

Background: Intravenous antibiotic infusion has been the standard prophylaxis for total joint arthroplasty surgery. However, infection rates still occur at 1%-2% in many series. Single-dose intra-articular antibiotics (IAAs) present a safe and potentially more effective prophylactic regime in total joint arthroplasty. This study aimed to assess the outcomes of a single-dose IAA injection on PJI rates in a single surgeon series of hip and knee arthroplasty. Methods: We reviewed the data of all patients operated on for a primary hip or knee replacement from 2010 to 2021. From January 2018, 1 gm of vancomycin in 10 ml of saline was injected into every total joint replacement after fascial closure. A comparison was made with PJI referencing the Australian National Joint Replacement Registry data on revision for the 2 periods: 2010-2017 and 2018-2021. Results: During the period without IAA (2010-2017) for TKR, 6 of 489 (1.2%), and for THR, 5 of 694 (0.7%) had PJI requiring revision surgery. In the period with IAA (2018-2021) for TKR, 0 of 214 (0%, P = .11), and for THR, 1 of 517 (0.2%, P = .19) PJI required revision surgery, but the overall incidence of PJI for TKR and THR was significantly reduced (P = .03). Conclusions: A single dose of intra-articular vancomycin 1 gm injected into the total joint replacement following fascial closure reduced the incidence of deep PJI requiring a revision surgery in a single-surgeon series. These results demonstrate significant benefits to this technique which merit further larger trials.

The use of intra-articular vancomycin is safe in primary hip and knee arthroplasty.

Background: The use of a single dose of intra-articular antibiotic (IAA) has been reported in reducing the rate of prosthetic joint injection after total hip and knee arthroplasty. We examine the safety of IAA in primary hip and knee replacement surgery and the blood levels and joint fluid levels of vancomycin utilising this technique. Methods: From August to October 2021, 68 patients undergoing primary total joint arthroplasty (THA & TKA) were given 1g vancomycin intra-articularly (IA)after closure of the fascia. All patients received 2g cefazolin intravenously (IV) 30 min prior to the procedure as is our standard prophylaxis, and 21 of the patients (IA + IV) were also administered an additional 1 gm vancomycin IV. Post-operative blood vancomycin, creatinine land eGFR level monitoring was performed d1 and d3. To determine the post-operative intra-articular vancomycin levels, surgical drain fluid was sampled at day 1 and 2, in 10 patients. Results: All patients had serum vancomycin levels measured on day 1 and 3. In the group where vancomycin was injected after fascial closure, the average blood vancomycin level day 1 was 5.2 µg/ml (range 2.0-10.9) and day 3 was <1.4 µg/ml. The average pre-op creatinine levels were 69.4 µmol/L (56.1-82.6) compared to 70.2 µmol/L (57.0-83.4) on day 1 and 66.1 µmol/L (52.6-79.6) on day 3, (p = 0.663). The average pre-op eGFR levels (ml/min/1.73 m2) were 82.2 (76.0-88.3) compared to 81.7 (75.6-87.8) on day 1 and 83.0 (76.8-89.2) on day 3 (p = 0.736). Samples of joint fluid aspirated from surgical drains on day 1 and day 2 showed average vancomycin levels of 224 µg/ml and 51 µg/ml respectively, significantly higher than the MIC for Staph aureus. Conclusions: The use of intra-articular vancomycin is safe in primary TJA, with no renal damage and delivers levels within the joint which are highly therapeutic for at least 48 h post injection.

Effect of Aspirin vs Enoxaparin on 90-Day Mortality in Patients Undergoing Hip or Knee Arthroplasty: A Secondary Analysis of the CRISTAL Cluster Randomized Trial.

Importance: Ischemic heart disease remains the leading cause of mortality following hip and knee arthroplasty. Due to its antiplatelet and cardioprotective properties, aspirin has been proposed as an agent that could reduce mortality when used as venous thromboembolism (VTE) prophylaxis following these procedures. Objective: To compare aspirin with enoxaparin in reducing 90-day mortality for patients undergoing hip or knee arthroplasty procedures. Design, Setting, and Participants: This study was a planned secondary analysis of the CRISTAL cluster randomized, crossover, registry-nested trial performed across 31 participating hospitals in Australia between April 20, 2019, and December 18, 2020. The aim of the CRISTAL trial was to determine whether aspirin was noninferior to enoxaparin in preventing symptomatic VTE following hip or knee arthroplasty. The primary study restricted the analysis to patients undergoing total hip or knee arthroplasty for a diagnosis of osteoarthritis only. This study includes all adult patients (aged ≥18 years) undergoing any hip or knee arthroplasty procedure at participating sites during the course of the trial. Data were analyzed from June 1 to September 6, 2021. Interventions: Hospitals were randomized to administer all patients oral aspirin (100 mg daily) or subcutaneous enoxaparin (40 mg daily) for 35 days after hip arthroplasty and 14 days after knee arthroplasty procedures. Main Outcomes and Measures: The primary outcome was mortality within 90 days. The between-group difference in mortality was estimated using cluster summary methods. Results: A total of 23 458 patients from 31 hospitals were included, with 14 156 patients allocated to aspirin (median [IQR] age, 69 [62-77] years; 7984 [56.4%] female) and 9302 patients allocated to enoxaparin (median [IQR] age, 70 [62-77] years; 5277 [56.7%] female). The mortality rate within 90 days of surgery was 1.67% in the aspirin group and 1.53% in the enoxaparin group (estimated difference, 0.04%; 95% CI, -0.05%-0.42%). For the subgroup of 21 148 patients with a nonfracture diagnosis, the mortality rate was 0.49% in the aspirin group and 0.41% in the enoxaparin group (estimated difference, 0.05%; 95% CI, -0.67% to 0.76%). Conclusions and Relevance: In this secondary analysis of a cluster randomized trial comparing aspirin with enoxaparin following hip or knee arthroplasty, there was no significant between-group difference in mortality within 90 days when either drug was used for VTE prophylaxis. Trial Registration: http://anzctr.org.au Identifier: ACTRN12618001879257.

Which hip morphology measures and patient factors are associated with age of onset and symptom severity in femoroacetabular impingement syndrome?

BACKGROUND: Bony morphology is central to the pathomechanism of femoroacetabular impingement syndrome (FAIS), however isolated radiographic measures poorly predict symptom onset and severity. More comprehensive morphology measurement considered together with patient factors may better predict symptom presentation. This study aimed to determine the morphological parameter(s) and patient factor(s) associated with symptom age of onset and severity in FAIS. METHODS: 99 participants (age 32.9 ± 10.5 years; body mass index (BMI 24.3 ± 3.1 kg/m2; 42% females) diagnosed with FAIS received standardised plain radiographs and magnetic resonance scans. Alpha angle in four radial planes (superior to anterior), acetabular version (AV), femoral torsion, lateral centre-edge, anterior centre-edge (ACEA) and femoral neck-shaft angles were measured. Age of symptom onset (age at presentation minus duration of symptoms), international Hip Outcome Tool-33 (iHOT-33) and modified UCLA activity scores were recorded. Backward stepwise regression assessed morphological parameters and patient factors (age, sex, BMI, symptom duration, annual income, private/public healthcare system accessed) to determine variables independently associated with onset age and iHOT-33 score. RESULTS: Earlier symptom onset was associated with larger superoanterior alpha angle (p = 0.007), smaller AV (p = 0.023), lower BMI (p = 0.010) and public healthcare system access (p = 0.041) (r2 = 0.320). Worse iHOT-33 score was associated with smaller ACEA (p = 0.034), female sex (p = 0.040), worse modified UCLA activity score (p = 0.010) and public healthcare system access (p < 0.001) (r2 = 0.340). CONCLUSIONS: Age of symptom onset was chiefly predicted by femoral and acetabular bony morphology measures, whereas symptom severity predominantly by patient factors. Factors measured explained a small amount of variance in the data; additional unmeasured factors may be more influential.

Moderators, Mediators, and Prognostic Indicators of Treatment With Hip Arthroscopy or Physical Therapy for Femoroacetabular Impingement Syndrome: Secondary Analyses From the Australian FASHIoN Trial.

BACKGROUND: Although randomized controlled trials comparing hip arthroscopy with physical therapy for the treatment of femoroacetabular impingement (FAI) syndrome have emerged, no studies have investigated potential moderators or mediators of change in hip-related quality of life. PURPOSE: To explore potential moderators, mediators, and prognostic indicators of the effect of hip arthroscopy and physical therapy on change in 33-item international Hip Outcome Tool (iHOT-33) score for FAI syndrome. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Overall, 99 participants were recruited from the clinics of orthopaedic surgeons and randomly allocated to treatment with hip arthroscopy or physical therapy. Change in iHOT-33 score from baseline to 12 months was the dependent outcome for analyses of moderators, mediators, and prognostic indicators. Variables investigated as potential moderators/prognostic indicators were demographic variables, symptom duration, alpha angle, lateral center-edge angle (LCEA), Hip Osteoarthritis MRI Scoring System (HOAMS) for selected magnetic resonance imaging (MRI) features, and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score. Potential mediators investigated were change in chosen bony morphology measures, HOAMS, and dGEMRIC score from baseline to 12 months. For hip arthroscopy, intraoperative procedures performed (femoral ostectomy ± acetabular ostectomy ± labral repair ± ligamentum teres debridement) and quality of surgery graded by a blinded surgical review panel were investigated for potential association with iHOT-33 change. For physical therapy, fidelity to the physical therapy program was investigated for potential association with iHOT-33 change. RESULTS: A total of 81 participants were included in the final moderator/prognostic indicator analysis and 85 participants in the final mediator analysis after exclusion of those with missing data. No significant moderators or mediators of change in iHOT-33 score from baseline to 12 months were identified. Patients with smaller baseline LCEA (ß = -0.82; P = .034), access to private health care (ß = 12.91; P = .013), and worse baseline iHOT-33 score (ß = -0.48; P < .001) had greater iHOT-33 improvement from baseline to 12 months, irrespective of treatment allocation, and thus were prognostic indicators of treatment response. Unsatisfactory treatment fidelity was associated with worse treatment response (ß = -24.27; P = .013) for physical therapy. The quality of surgery and procedures performed were not associated with iHOT-33 change for hip arthroscopy (P = .460-.665 and P = .096-.824, respectively). CONCLUSION: No moderators or mediators of change in hip-related quality of life were identified for treatment of FAI syndrome with hip arthroscopy or physical therapy in these exploratory analyses. Patients who accessed the Australian private health care system, had smaller LCEAs, and had worse baseline iHOT-33 scores, experienced greater iHOT-33 improvement, irrespective of treatment allocation.

Effect of Aspirin vs Enoxaparin on Symptomatic Venous Thromboembolism in Patients Undergoing Hip or Knee Arthroplasty: The CRISTAL Randomized Trial.

Importance: There remains a lack of randomized trials investigating aspirin monotherapy for symptomatic venous thromboembolism (VTE) prophylaxis following total hip arthroplasty (THA) or total knee arthroplasty (TKA). Objective: To determine whether aspirin was noninferior to enoxaparin in preventing symptomatic VTE after THA or TKA. Design, Setting, and Participants: Cluster-randomized, crossover, registry-nested trial across 31 hospitals in Australia. Clusters were hospitals performing greater than 250 THA or TKA procedures annually. Patients (aged ≥18 years) undergoing hip or knee arthroplasty procedures were enrolled at each hospital. Patients receiving preoperative anticoagulation or who had a medical contraindication to either study drug were excluded. A total of 9711 eligible patients were enrolled (5675 in the aspirin group and 4036 in the enoxaparin group) between April 20, 2019, and December 18, 2020. Final follow-up occurred on August 14, 2021. Interventions: Hospitals were randomized to administer aspirin (100 mg/d) or enoxaparin (40 mg/d) for 35 days after THA and for 14 days after TKA. Crossover occurred after the patient enrollment target had been met for the first group. All 31 hospitals were initially randomized and 16 crossed over prior to trial cessation. Main Outcomes and Measures: The primary outcome was symptomatic VTE within 90 days, including pulmonary embolism and deep venous thrombosis (DVT) (above or below the knee). The noninferiority margin was 1%. Six secondary outcomes are reported, including death and major bleeding within 90 days. Analyses were performed by randomization group. Results: Enrollment was stopped after an interim analysis determined the stopping rule was met, with 9711 patients (median age, 68 years; 56.8% female) of the prespecified 15 562 enrolled (62%). Of these, 9203 (95%) completed the trial. Within 90 days of surgery, symptomatic VTE occurred in 256 patients, including pulmonary embolism (79 cases), above-knee DVT (18 cases), and below-knee DVT (174 cases). The symptomatic VTE rate in the aspirin group was 3.45% and in the enoxaparin group was 1.82% (estimated difference, 1.97%; 95% CI, 0.54%-3.41%). This failed to meet the criterion for noninferiority for aspirin and was significantly superior for enoxaparin (P = .007). Of 6 secondary outcomes, none were significantly better in the enoxaparin group compared with the aspirin group. Conclusions and Relevance: Among patients undergoing hip or knee arthroplasty for osteoarthritis, aspirin compared with enoxaparin resulted in a significantly higher rate of symptomatic VTE within 90 days, defined as below- or above-knee DVT or pulmonary embolism. These findings may be informed by a cost-effectiveness analysis. Trial Registration: ANZCTR Identifier: ACTRN12618001879257.

How does employees' behavior change how we feel about their organization? Transfer of affective impressions between employees and organizations.

Stable impressions of how good, powerful, and active an organization is may be jointly shared with their employees, yet the impression produced by employees' behavior may be transferred back to the organization. Our first studies shows that stable impressions, or sentiments, of organizations (e.g., a library) are fairly similar to those of their employees (e.g., an employee of a library), with organizations viewed as more powerful and morally extreme than their employees. Our principal studies along with affect control theory simulations show how the impressions created by an employee's behavior toward a customer (e.g., an employee of a library shouts at a customer) transfer to the employee's organization. Affect control theory simulations predict the impressions of an organization as well as they predict impressions of the individual employee. Regression and classification analyses give support to impression transfer, with the most transfer occurring for evaluation impressions, and more so for transferring bad impressions rather than good ones. Therefore, this research shows how a single behavior by a rank-and-file employee can shape outsider's impressions of organizations and the potential for applying affect control theory predictions to impressions of organizations.

Pilar Cysts of the Head and Neck: A Case Report.

Pilar cysts, a subtype of sebaceous cysts, are benign masses often commonly found on the scalp, back, and face. They are common amongst women and carry a low potential for malignancy. These lesions arise due to the buildup of keratin in the skin pore, blocking the exit port of sebaceous gland secretions. The buildup of keratin material ultimately leads to cyst formation. The complications of these cysts include inflammation, rupture, infection, and transformation to cancerous lesions in some rare instances. This is a case of a 59-year-old female with a long-standing history of recurrent complicated pilar cysts who presented to the outpatient surgical clinic for assessment of cysts for removal. A total of eleven cysts were successfully removed through two separate surgeries.

Thermal Stability and Utility of Dienes as Protecting Groups for Acrylamides.

Acrylamides are privileged electrophiles used in targeted covalent therapies, often installed at the end of a synthetic sequence due to their reactive nature. Herein, we report several diene-acrylamide adducts with a range of thermal stabilities toward retro-Diels-Alder deprotection of the acrylamide, enabling this masked functionality to be introduced early in a synthetic route and deprotected in a specific temperature range. Through kinetic studies, we identify solvent and structural trends that impact the stability of trimethylsilyl cyclopentadiene (TMS-CP) acrylamide adducts. TMS-CP protected acrylamides were installed on several amine-containing drugs, whose acrylamides were thermally unveiled (T = 160 °C, time ≤ 1 h) in moderate to high yields. We also showcase the potential utility of this protection strategy by improving the yield of a base-promoted SNAr reaction when the acrylamide is masked.

Adherence by orthopaedic surgeons to AHPRA and Australian Orthopaedic Association advertising guidelines.

OBJECTIVES: To examine adherence to Australian Health Practitioner Regulation Agency (AHPRA) and Australian Orthopaedic Association (AOA) advertising guidelines by AOA members. DESIGN, SETTING: Cross-sectional survey, Australia. PARTICIPANTS: Two samples of AOA member orthopaedic surgeons: 81 randomly selected from a list of AOA members with publicly available contact details (AOA random sample); and a sample obtained by searching with Google for "orthopaedic surgeon" and the name of the major city in each of the eight Australian states and territories in turn; the top eight results for each search were considered for inclusion (AOA Google sample). MAIN OUTCOME MEASURES: Non-compliance of advertising material, by surgeon sample, with the AHPRA and AOA guidelines; associations between non-compliance and sample, state, location (metropolitan, regional), and subspecialty. RESULTS: Of the 81 surgeons in the AOA random sample, 52 (64%) were non-compliant with at least one aspect of the AHPRA guidelines, and 53 (65%) were non-compliant with at least one aspect of the AOA guidelines. Of the 59 surgeons in the AOA Google sample, 48 were non-compliant with the AHPRA guidelines (81%) and 46 with the AOA guidelines (78%). Incidence of non-compliance with the AHPRA guidelines was influenced by sample source (AOA Google v AOA random: incidence rate ratio [IRR], 1.37; 95% CI, 1.01-1.87), but not non-compliance with the AOA guidelines (IRR, 1.09; 95% CI, 0.77-1.55). CONCLUSION: A large proportion of AOA members who advertise online do not comply with AHPRA and AOA advertising guidelines.

Modular Total Femur Replacement for Staged Total Femur Replacement.

As the numbers of arthroplasties performed worldwide increase, so do complications such as prosthetic joint infection. Cases that require a two-stage revision of a total femur replacement in the femur pose an ongoing challenge to the modern orthopedic surgeon. Unlike antibiotic spacers in hip and knee arthroplasty, there lacks a commercially available cement spacer for use in total femur replacements. We describe a novel technique for the intraoperative fabrication of a total femur spacer which uses modular components. As such, our technique is unique as it is modular and, therefore, highly customisable to each individual patient. Individual components can be made by different members of the team simultaneously and then assembled to make the final construct, thereby minimizing operative time. Furthermore, the inherent stability of the spacer allows immediate partial weightbearing and functional rehabilitation while patients are waiting for their second-stage procedure.

Multi-centre randomised controlled trial comparing arthroscopic hip surgery to physiotherapist-led care for femoroacetabular impingement (FAI) syndrome on hip cartilage metabolism: the Australian FASHIoN trial.

BACKGROUND: Arthroscopic surgery for femoroacetabular impingement syndrome (FAI) is known to lead to self-reported symptom improvement. In the context of surgical interventions with known contextual effects and no true sham comparator trials, it is important to ascertain outcomes that are less susceptible to placebo effects. The primary aim of this trial was to determine if study participants with FAI who have hip arthroscopy demonstrate greater improvements in delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) index between baseline and 12 months, compared to participants who undergo physiotherapist-led management. METHODS: Multi-centre, pragmatic, two-arm superiority randomised controlled trial comparing physiotherapist-led management to hip arthroscopy for FAI. FAI participants were recruited from participating orthopaedic surgeons clinics, and randomly allocated to receive either physiotherapist-led conservative care or surgery. The surgical intervention was arthroscopic FAI surgery. The physiotherapist-led conservative management was an individualised physiotherapy program, named Personalised Hip Therapy (PHT). The primary outcome measure was change in dGEMRIC score between baseline and 12 months. Secondary outcomes included a range of patient-reported outcomes and structural measures relevant to FAI pathoanatomy and hip osteoarthritis development. Interventions were compared by intention-to-treat analysis. RESULTS: Ninety-nine participants were recruited, of mean age 33 years and 58% male. Primary outcome data were available for 53 participants (27 in surgical group, 26 in PHT). The adjusted group difference in change at 12 months in dGEMRIC was -59 ms (95%CI - 137.9 to - 19.6) (p = 0.14) favouring PHT. Hip-related quality of life (iHOT-33) showed improvements in both groups with the adjusted between-group difference at 12 months showing a statistically and clinically important improvement in arthroscopy of 14 units (95% CI 5.6 to 23.9) (p = 0.003). CONCLUSION: The primary outcome of dGEMRIC showed no statistically significant difference between PHT and arthroscopic hip surgery at 12 months of follow-up. Patients treated with surgery reported greater benefits in symptoms at 12 months compared to PHT, but these benefits are not explained by better hip cartilage metabolism. TRIAL REGISTRATION DETAILS: Australia New Zealand Clinical Trials Registry reference: ACTRN12615001177549 . Trial registered 2/11/2015.

Silacycle-Templated Intramolecular Diels-Alder Cyclizations for the Diastereoselective Construction of Complex Carbon Skeletons.

The utility of the dioxasiline ring as a π-facial directing group in the intramolecular Diels-Alder cyclization is explored. An initial investigation of substrate scope demonstrates that the rigidity of this directing group delivers robust stereocontrol across a number of substrates, affording single diastereomers in moderate to good yields. A mechanistic investigation reveals that the reactive diene is formed through γ deprotonation followed by [1,5] hydride shifts.

Total volume of cam deformity alone predicts outcome in arthroscopy for femoroacetabular impingement.

PURPOSE: Rates for arthroscopic surgery for femoroacetabular impingement (FAI) are rising and there is growing concern related to the effectiveness and costs associated with this treatment. There is a general lack of consensus as to the criteria for surgical selection of patients. The purpose of this study was to determine whether patient outcome following arthroscopic surgery for FAI could be predicted based on the size and location of deformity. The specific questions were: (1) what is the morphology of FAI in terms of size and location of deformity in a cohort of patients selected for surgery? (2) Do morphological factors predict postoperative improvement in hip scores? (3) Do morphological factors predict preoperative hip scores? (4) Are there clusters of morphological factors which explain postsurgical improvement in hip scores? MATERIALS AND METHODS: Computer tomography (CT) surgical plans of 90 hips in 79 patients who had undergone primary hip arthroscopy for FAI were retrospectively reviewed. Four parameters for the femur and acetabulum were created: total depth of deformity, maximal depth, extent and the position of maximal deformity. This data were compared with prospectively acquired preoperative and postoperative patient outcome data using generalised linear models. RESULTS: The cohort comprised 33 males and 46 females aged 37.9 (18-61). The majority (74%) had mixed morphology, 23% isolated cam, and 3% isolated pincer. Overall, the bone depth was greatest and more extensive on the femur. Increased total additional cam deformity alone predicted poorer postoperative outcome (p = 0.045). None of the morphological factors were related to preoperative scores and there was no association between the meta-variables and postoperative outcome. CONCLUSIONS: The results of this study indicate that a greater total volume of cam deformity led to poorer postoperative patient outcome scores at 1 year. This information provides the surgeon with more accurate patient-specific data for prediction of expected outcomes. LEVEL OF EVIDENCE: Level III diagnostic.

Relative and Absolute Structure Assignments of Alkenes Using Crystalline Osmate Derivatives for X-ray Analysis.

Osmium tetroxide and TMEDA form stable crystalline adducts with alkenes. The structure of liquid alkenes can be determined through the X-ray analysis of these derivatives. Osmium, a heavy atom, facilitates the crystallographic analysis and the determination of the absolute configuration using common Mo X-ray sources. The utility of this method for assigning structures and absolute configurations was demonstrated on a number of unsaturated substrates that include simple alkenes, enones, enol ethers, and silyl enol ethers.

Total Synthesis and Structure Revision of (-)-Illisimonin A, a Neuroprotective Sesquiterpenoid from the Fruits of Illicium simonsii.

Illisimonin A was isolated from Illicium simonsii and has a previously unreported tricyclic carbon framework. It displayed neuroprotective effects against oxygen-glucose deprivation-induced cell injury in SH-SY5Y cells. It incorporates a highly strained trans-pentalene ring system. We report the first synthesis of (±)-illisimonin A. Notable steps in the route include a 1,3-dioxa-2-silacyclohexene templated Diels-Alder cycloaddition and type-3 semipinacol rearrangement to generate the trans-pentalene. The final step is an iron-catalyzed C-H oxidation. The synthetic route is robust, with 94 mg of racemic material prepared in a single pass. Resolving an intermediate enabled the synthesis of natural (-)-illisimonin A. The absolute configuration of (-)-illisimonin A was revised to 1S,4S,5S,6S,7R,9R,10R based on the X-ray structure of a heavy-atom analogue.

Does soft tissue balancing using intraoperative pressure sensors improve clinical outcomes in total knee arthroplasty? A protocol of a multicentre randomised controlled trial.

INTRODUCTION: Soft tissue imbalance is considered to be a major surgical cause of dissatisfaction following total knee arthroplasty (TKA). Surgeon-determined manual assessment of ligament tension has been shown to be a poor determinant of the true knee balance state. The recent introduction of intraoperative sensors, however, allows surgeons to precisely quantify knee compartment pressures and tibiofemoral kinematics, thereby optimising coronal and sagittal plane soft tissue balance. The primary hypothesis of this study is that achieving knee balance with use of sensors in TKA will improve patient-reported outcomes when compared with manual balancing. METHODS AND ANALYSIS: A multicentred, randomised controlled trial will compare patient-reported outcomes in 222 patients undergoing TKA using sensor-guided balancing versus manual balancing. The sensor will be used in both arms for purposes of data collection; however, surgeons will be blinded to the pressure data in patients randomised to manual balancing. The primary outcome will be the change from baseline to 1 year postoperatively in the mean of the four subscales of the Knee Injury and Osteoarthritis Outcome Score (KOOS4) that are most specific to TKA recovery: pain, symptoms, function and knee-related quality of life. Secondary outcomes will include the surgeon's capacity to determine knee balance, radiographic and functional measures and additional patient-reported outcomes. Normality of data will be assessed, and a Student's t-test and equivalent non-parametric tests will be used to compare differences in means among the two groups. ETHICS AND DISSEMINATION: Ethics approval was obtained from South Eastern Sydney Local Health District, Approval (HREC/18/POWH/320). Results of the trial will be presented at orthopaedic surgical meetings and submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ACTRN#12618000817246.

Catalytic Enantioselective Allylations of Acetylenic Aldehydes via 2-Propanol-Mediated Reductive Coupling.

Cyclometalated π-allyliridium C,O-benzoates modified by ( S)-SEGPHOS or ( S)-Cl,OMe-BIPHEP catalyze enantioselective 2-propanol-mediated reductive couplings of diverse nonmetallic allyl pronucleophiles with the acetylenic aldehyde TIPSC≡CCHO. Absolute stereochemistries of the resulting secondary homoallylic-propargylic alcohols were assigned using Rychnovsky's competing enantioselective conversion method.

Heteroatom-Directed Acylation of Secondary Alcohols To Assign Absolute Configuration.

Birman's HBTM catalyst is effective for the enantioselective acylation and kinetic resolution of benzylic secondary alcohols. The enantioselective acylation has now been extended to secondary alcohols bearing electron-withdrawing groups such as halides and other heteroatoms. The level of selectivity is modest to good and is sufficient for determining configuration using the competing enantioselective conversion method. A mathematical analysis identifies conditions for achieving maximum differences in conversion and, consequently, assigning configuration with greater confidence. The new method is effective for halohydrins and secondary-tertiary 1,2-diols and was used to confirm the configuration of two inoterpene natural products.