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15-year patient-reported outcomes of a cemented flanged cup and stem combination in primary total hip arthroplasty: A New Zealand study
(SAGE, 2026) Pearce, Amy; Joshi, Chaitanya; Chan, Georgina; Lamberton, Tony; MacLean, Simon; Vane, Andrew; Hébert-Losier, Kim
Methods: We investigated 15-year patient-reported outcomes (PROMs) and their predictors in primary total hip arthroplasty (THA) for osteoarthritis using a cemented flanged cup and stem from a regional joint registry in New Zealand. Regional data were collected for all primary THAs with this cemented combination from 1 January 2003 to 30 June 2023 who had recorded PROMs on at least 1 occasion (n = 263). PROMs included Oxford Hip Score, Western Ontario and McMaster Universities Arthritis Index and Veterans Rand-12, evaluated against patient age, ethnicity, sex, body mass index (BMI), funding pathway, and American Society of Anesthesiologists (ASA) rating. Results: Significant improvements across preoperative PROMs were noted 1-year post-surgery, with a mean change above 23 in the Oxford Hip Score maintained at 5, 10, and 15 years (p ⩽ 0.001). Conclusions: Regression analysis indicated that being female, public funding, and higher BMI were associated with worse preoperative PROMs. Poorer preoperative scores, older age and ASA 3 rating correlated with poorer postoperative outcomes.
Exploring the reliability of isometric benchmark tests and their relationship to performance characteristics in elite track sprint cyclists
(Taylor & Francis, 2025) Thompson, Roné; Paton, Carl D.; Bini, Rodrigo Rico; Hébert-Losier, Kim
Benchmark tests in competitive cycling identify talent, individualise training, and monitor performance. However, varying protocols often produce conflicting results, reducing comparability. Isometric tests are prevalent, but reliability and performance correlation are underexplored. Determine the test–retest reliability of benchmark test metrics in elite track sprint cyclists and their relationship to a performance outcome. Nineteen elite track sprint cyclists (12 males, 7 females) completed seven benchmark tests across two days: modified sit-and-reach; on-bike rolling seated maximum 6-s sprints; 3-s bilateral on-bike isometrics at 90° crank angle; 3-s prone bench pull isometrics; 3-s lumbar extension isometrics; 3-s seated off-bike isometrics; and modified plank endurance. For the performance outcome, a third session within 7 days assessed peak power using an inertial load cycle ergometer. All tests showed excellent measurement consistency (ICC3,1 ≥ 0.92), with low systematic bias (p ≥ 0.063), though confidence interval varied due to modest sample size. High test–retest reliability was supported by low typical errors (CV 2.0–5.5%; 9.6% for endurance). Nine benchmark metrics, including bilateral isometric measures, showed moderate to excellent correlation with peak power output (r = 0.52–0.94, p ≤ 0.023); six remained statistically significant after Bonferroni correction (p ≤ 0.005). All benchmark metrics were reliable, with six strongly and statistically significantly associated with performance.
Running shoe recommendations based on gait analysis improve perceptions of comfort, performance and injury risk: A single-blind randomised crossover trial
(Wiley, 2025) Fife, Andrew; Esculier, Jean-François; Ramsey, Codi; Hébert-Losier, Kim; Mendias, Christopher
Objectives: We examined how shoe recommendation based on gait analysis influences subjective perceptions of comfort, performance and injury reduction in runners while monitoring spatiotemporal and kinematic parameters. Design: Single-blind crossover randomised controlled trial with repeated measures. Method: Twenty-one women runners completed a clinical gait analysis and four 5-min treadmill trials at a self-selected comfortable speed sequentially in their own shoes (OS), the first experimental shoes (randomised), their OS, and the second experimental shoes (randomised). The two experimental shoes were identical except for their colour (randomised) and were presented to runners as either a ‘basic’ shoe or, deceptively, a ‘gait-matched’ shoe selected for them based on the clinical gait analysis conducted. Results: Running Comfort Assessment Tool (RUN-CAT) scores and 100 mm visual analogue scale ratings of subjective comfort, performance and injury reduction differed significantly between own and experimental shoes (p < 0.001). Post-hoc comparisons revealed that runners’ OS were the most comfortable (83.3 ± 3.8 mm) followed by gait-matched (66.1 ± 21.5 mm) and then basic (49.0 ± 24.1 mm) shoes. RUN-CAT, performance and injury reduction ratings were similar between own and gait-matched shoes, but gait-matched shoes had better mean difference (95% confidence intervals), RUN-CAT (15.6 mm [5.7, 25.5]), performance (17.1 mm [5.6, 28.6]) and injury reduction (30.1 mm [8.9, 51.2]) scores than the basic shoes. Discrete spatiotemporal, foot strike angle and resultant tibial acceleration parameters were not significantly different between shoes (p ≥ 0.157). Most runners overall preferred their OS (71.4%), followed by gait-matched (23.8%) and basic (4.8%) shoes. Conclusions: Shoe recommendation and description can significantly affect subjective shoe comfort and overall preferences without significantly altering spatiotemporal and kinematic parameters. Runners should be cautious while choosing shoes based on recommendations and descriptors derived from gait analysis or based solely on perceived comfort as runners’ subjective perceptions can be artificially manipulated.
Some chemistry of orthomanganated ketones
(The University of Waikato, 1986) Gommans, Louis H. P.; Main, Lyndsay; Nicholson, Brian K.
The major part of this thesis describes the preparation and reactions of orthomanganated aromatic ketones, such as (1), diagram. Among the new species characterised are substituted acetophenones, analogues of (1), namely: 3,4,5-trimethoxy (3); 4,5,6-trimethoxy (4); 3-t-butyldimethylsiloxy-4,5-dimethoxy (5); 4,5-dimethoxy (6); 5,6-dimethoxy (7); 3-benzyloxy-4,5-dimethoxy (8); and 3-t-butyldimethylsiloxy (9). Hetero aromatic ketones have been used to prepare the corresponding orthomanganated compounds (10), (11), (12), (14) and (15) from the respective ketones 2-acetylthiophene, 3-acetyl-2,5-dimethylthiophene, 2-acetyl-N-methylpyrrole, 3-acetylindole and 2- acetylfuran. The crystal structure of η²-(3-acetyl-2,5-dimethylthien-4-yl)tetracarbonylmanganese (11) has been determined. The 5-manganated derivative (13) of flavanone has also been made. Attempted orthometallations of acetophenones with C₆H₅CH₂Co(CO)₄, C₆H₅CH₂Fe(CO)₂Cp and Pd(OAc)₂ were unsuccessful. Reaction of (4) with Br₂ in carbon tetrachloride gave the orthobromoacetophenone 2'-bromo-3' ,4' ,5'-trimethoxyacetophenone (21) plus [Mn(CO)₄Br]₂. The corresponding orthoiodoacetophenone (28) and [Mn(CO)₄Cl]₂ was obtained using ICl. Other orthohalogenated ketones were obtained similarly. The reactions were sometimes unsuccessful (e.g. for (1)) or complicated (e.g. (5) competitive ring bromination). Oxidation of (1) or (4) with cerium (IV) ammonium nitrate (0.5 mol) in CD₃CO₂D gives the corresponding orthomonodeuterio acetophenones (19) or (20). A by-product from the oxidation of (4), the cyclic hemiketal, (36), was identified by X-ray crystal structure analysis, and one other product, the lactone, (37) was identified spectrally. Determination by ¹H-NMR of the ratio of the 3-deuterio- (1a) to 3-protio- (1) formed in the orthometallation of orthomonodeuterio acetophenone (19) by C₆H₅CH₂Mn(CO)₅ gave a hydrogen isotope effect of 3.6. Similarly, for 2'-deuterio-3' ,4' ,5'-trimethoxyacetophenone (20) the value was 2.9. However, when the orthodeuterioacetophenone (19) was reacted with cis - C₆H₅CH₂Mn(CO)₄P(C₆H₅)₃ the product fac-η²-(2-acetylphenyl) tricarbonyltriphenylphosphinomanganese (16)/(16a) showed a D/H ratio of only 1.1. Implications of these isotope effects for mechanisms are discussed. Reactions of orthomanganted ketones with vinyl reagents in the presence of Pd(II) were studied in two solvents. In methanol, (1) with methyl acrylate (H₂C=CHCOOCH₃) and Li₂PdCl₄ (1 mol) gave methyl E-3-(2-acetylphenyl)acrylate (38). Similarly η²-(2-acetylthien-3-yl)-tetracarbonylmanganese (10) gave methyl E-3-(2-acetylthien-3-yl) acrylate (40). A variety of other products from coupling reactions with vinyl acetate, acrylonitrile, styrene, methyl vinyl ketone, acrolein and allyl alcohol are reported, and possible mechanisms for coupling reactions are discussed. In acetonitrile as solvent, under reflux, with PdCl₂ (1 mol) and excess LiCl, some of the orthomanganated ketones provided new routes to indenes in their reaction with methyl acrylate. Thus (4) gave methyl 3-methyl-5,6,7-trimethoxyindene-2-carboxylate (53), and (2) and (3) gave the corresponding indenes [(51) and (49)]. The thiophene derivative η²-(3-acetyl-2,5-dimethylthien-4-yl)tetracarbonylmanganese (11) also gave the corresponding bicyclic compound, methyl 2,5,6-trimethyl-3H-cyclopenta-[c]-thiophene-4-carboxylate, (54) but the major product was the arylated acrylate ester (55) in this case. In reaction of (2) with HgC1₂ in refluxing methanol, trans-metallation occurs to form chloro(2-acetyl-5-methoxyphenyl)mercury(II) (57). The corresponding mercuric chloride of (1), that is, chloro(2-acetylphenyl)mercury(II) (56), has also been prepared and its crystal structure is reported. In a separate study dodecahydrotriphenylene (C₁₈H₂₄) (58) has been used to prepare the isoelectronic metal arene π-complexes structures η⁶-(C₁₈H₂₄)Cr(CO)₃ (59) and η⁶-(C₁₈H₂₄)Mn(CO)₃⁺ (60). The crystal structures of the former and of the two distinct crystalline modifications of the latter, as BF₄⁻ salts are reported and compared.
Instruction systolic arrays for exact parallel linear algebraic computation
(The University of Waikato, 1988) Krishnamurthy, V.; de Vel, Olivier
This thesis develops new computational algorithms for parallel/distributed error-free (exact) rational (real and complex) computing and its applications to exact linear algebraic computing. The practical realization of these parallel algorithms in VLSI systems using a new concept known as Instruction Systolic Arrays (ISA) is considered. Thus, the thesis represents the author’s contribution to the theory, design, and implementation of parallel/distributed algorithms for exact rational/linear algebraic computing using ISA processors. This thesis consists of six chapters with the following contents. CHAPTER 1 INSTRUCTION SYSTOLIC ARRAYS - A PROGRAMMABLE PARALLEL ARCHITECTURE Chapter 1 introduces the concept of Instruction Systolic arrays (ISA). The ISA is a new versatile programmable parallel architecture that retains all the advantages of systolic arrays. In the ISA, instructions and boolean selectors are pumped through the processing array. The ISA has tremendous potential for VLSI computing because of its ability to execute different types of programs on the same processing array. We also introduce a variant of the ISA known as the Single Instruction Systolic Array (SISA). In the SISA, single instructions and selectors are pumped through the processing array. CHAPTER 2 INSTRUCTION SYSTOLIC ARRAYS FOR DISTRIBUTED CHINESE REMAINDERING/ INTERPOLATION ALGORITHMS We present a parallel/ distributed algorithm for a fundamental problem in Numerical Computing/algebraic computing, namely interpolation and the closely related Chinese remaindering. The ISA implementation of this algorithm is described. A generalization of the interpolation algorithm for multivariable is then presented. The multivariable interpolation algorithm can be realized in a ISA as well as in a pyramid architecture. The Occam simulation of a pyramid for multivariable interpolation is also described. We then present a parallel/ distributed algorithm for rational function interpolation and consider its ISA implementation. CHAPTER 3 PARALLEL MATRIX COMPUTATION USING ISA This chapter introduces a parallel algorithm for the generalized inversion (g-inversion) of matrices, which involves parallel matrix addition and multiplication operations. The ISA implementation of this algorithm is described. The solution of a homogeneous system of linear algebraic equations is based on g-inverse computation and we indicate its ISA implementation. The solution of such equations has important practical applications in finding Petri net invariants, chemical equation balancing and dimensional analysis. Two other important g-inversion algorithms - one iterative and the other direct - are also described. CHAPTER 4 PARALLEL ERROR-FREE RATIONAL ARITHMETIC - ISA IMPLEMENTATION This chapter introduces a new parallel error-free (exact) rational arithmetic system called Parallel Rational Hensel code arithmetic (Para-Hensel code or PHC). We introduce algorithms for parallel element-wise arithmetic operations, and for encoding and decoding PHC codes. We briefly indicate the ISA implementation of these algorithms. We also consider the application of PHC for exact parallel matrix g-inversion with systolic processors. CHAPTER 5 PARALLEL COMPLEX RATIONAL AND MATRIX ARITHMETIC USING GAUSSIAN PRIME CODES In this chapter, we introduce a new parallel exact complex rational arithmetic system based on Gaussian prime codes. Two closely related methods for constructing these codes are described. The first method uses several distinct (multiple) Gaussian primes to construct Gauss-Hensel codes (GHC). The second method uses the powers of one or more Gaussian primes to construct Gauss p-adic codes (GPC). Their practical applications and extension to parallel inversion of complex matrices are described. These systems are amenable for massively parallel realization. CHAPTER 6 ISA - APPLICATIONS TO ARRAY PROCESSING AND REAL-TIME COMPUTING This chapter considers the suitability of the ISA for vector/ array processing computers. We also consider the relationship of the ISA to wavefront processing and dataflow computing. We then describe a linear variant of the ISA known as the Linear ISA (LISA), which is an area efficient architecture. We then briefly indicate some possible application areas of the ISA: real-time robot control applications and high-speed vision systems.