Browsing by Author "Johnston, Kelly"

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    The Application of the Reference Finite Helical Axis for Characterizing Knee Joint Kinematics
    (2022-01) Bugajski, Tomasz; Ronsky, Janet; Manske, Sarah; Johnston, Kelly
    Altered knee kinematics are an important biomechanical marker for the development of tibiofemoral osteoarthritis (OA). They are associated with altered cartilage contact areas, resulting in forces acting on unadapted cartilage that may degrade over time. The conventional approach to quantify knee kinematics is with Cardan angles, but the uncommon helical axis (HA) approach may provide supplementary information. However, the HA is susceptible to stochastic errors when angular displacements are small. To alleviate this error, a reference position may be used that permits larger angular displacements. However, more assessments are required to determine the utility of this reference finite helical axis (rFHA) method to provide biomechanical markers of tibiofemoral OA. The purpose of this thesis was to technically evaluate the rFHA and demonstrate its ability to distinguish knee kinematics of high tibiofemoral OA risk individuals. Technical evaluations consisted of 1) determining the effect of different smoothing techniques on rFHA accuracy, 2) assessing the sensitivity of the rFHA to reference position misalignments, and 3) comparing rFHA measures between an optical motion camera system (OMCS) and highspeed biplanar videoradiography system (HSBV). The utility of the rFHA was demonstrated by applying it to high tibiofemoral OA risk populations, specifically anterior cruciate ligament repaired (ACLR) knees and older knees. A spline filter with outlier removal process was the top performing smoothing technique for rFHA accuracy, providing a 72.2-80.1% improvement in rotational speed differences. Substantial differences of the rFHA measures were determined with misaligned reference positions, ranging from 1.17-19.53 mm and 0.77-5.45 deg. rFHA measure differences were also found between the OMCS and HSBV, ranging from 10.19-58.03 mm and 3.39-13.63 deg. Finally, kinematic trends were found in ACLR knees during a vertical drop jump, showing greater magnitudes of rFHA dispersion and helical internal rotation than healthy knees (dispersion: 0.46 deg; helical internal rotation: 2.18 deg). Additionally, significantly different rFHA path lengths were found between older and younger asymptomatic knees during walking (10.60 mm, p = 0.01). These findings demonstrate the utility of the rFHA in biomechanics, providing a supplementary method of characterizing knee kinematics and distinguishing the movement patterns of healthy individuals from tibiofemoral OA prone individuals.
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    Bilateral Femoral Insufficiency Fractures Likely Related to Long-Term Alendronate Therapy
    (2011-05-05) Gudena, Ravindra; Werle, Jason; Johnston, Kelly
    Osteoporosis-related fractures are a major public health problem and one in two women and one in four men are affected with osteoporosis-related fractures. Alendronate (Fosamax) is one of the first bisphosphonates used to treat osteoporosis effectively. Recently, however, there is a concern regarding long bone insufficiency fractures related to long-term alendronate therapy. We report a case of bilateral femoral insufficiency fractures likely related to long-term alendronate therapy, the classic symptoms, signs, and treatment of these fractures.
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    Effect of a prebiotic supplement on knee joint function, gut microbiota, and inflammation in adults with co-morbid obesity and knee osteoarthritis: study protocol for a randomized controlled trial
    (2021-04-07) Fortuna, Rafael; Hart, David A; Sharkey, Keith A; Schachar, Rachel A; Johnston, Kelly; Reimer, Raylene A
    Abstract Background Osteoarthritis (OA) is a chronic and painful condition where the articular cartilage surfaces progressively degenerate, resulting in loss of function and progressive disability. Obesity is a primary risk factor for the development and progression of knee OA, defined as the “metabolic OA” phenotype. Metabolic OA is associated with increased fat deposits that release inflammatory cytokines/adipokines, thereby resulting in systemic inflammation which can contribute to cartilage degeneration. There is currently no cure for OA. Prebiotics are a type of dietary fiber that can positively influence gut microbiota thereby reducing systemic inflammation and offering protection of joint integrity in rodents. However, no human clinical trials have tested the effects of prebiotics in adults with obesity suffering from knee OA. Therefore, the purpose of this double-blind, placebo-controlled, randomized trial is to determine if prebiotic supplementation can, through positive changes in the gut microbiota, improve knee function and physical performance in adults with obesity and knee OA. Methods Adults (n = 60) with co-morbid obesity (BMI > 30 kg/m2) and knee OA (Kellgren-Lawrence grade II–III) will be recruited from the Alberta Hip and Knee Clinic and the Rocky Mountain Health Clinic and surrounding community of Calgary, Canada, and randomized (stratified by sex, BMI, and age) to prebiotic (oligofructose-enriched inulin; 16 g/day) or a calorie-matched placebo (maltodextrin) for 6 months. Anthropometrics, performance-based tests, knee pain, serum inflammatory markers and metabolomics, quality of life, and gut microbiota will be assessed at baseline, 3 months, 6 months (end of prebiotic supplementation), and 3 months following the end of the prebiotic supplementation. Clinical significance There is growing pressure on health care systems for aggressive OA treatment such as total joint replacement. Less aggressive, yet effective, conservative treatment options have the potential to address the growing prevalence of co-morbid obesity and knee OA by delaying the need for joint replacement or ideally preventing its need altogether. The results of this clinical trial will provide the first evidence regarding the efficacy of prebiotic supplementation on knee joint function and pain in adults with obesity and knee OA. If successful, the results may provide a simple, safe, and easy to adhere to intervention to reduce knee joint pain and improve the quality of life of adults with co-morbid knee OA and obesity. Trial registration Clinical Trials.gov NCT04172688 . Registered on 21 November 2019.
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    Understanding the role of total knee arthroplasty for primary treatment of tibial plateau fracture: a systematic review of the literature
    (2020-05-25) Wong, Murray T; Bourget-Murray, Jonathan; Johnston, Kelly; Desy, Nicholas M
    Abstract Background Surgical fixation of tibial plateau fracture in elderly patients with open reduction and internal fixation (ORIF) provides inferior outcomes compared with younger patients. Primary total knee arthroplasty (TKA) may be of benefit in elderly patients with a combination of osteoporotic bone and metaphyseal comminution. However, there continues to be conflicting evidence on the use of TKA for primary treatment of tibial plateau fracture. This systematic review was performed to quantify the outcomes and perioperative complication rates of TKA for primary treatment of tibial plateau fracture. Materials and methods A comprehensive search of MEDLINE, Embase, and PubMed databases from inception through March 2018 was performed in accordance with PRISMA guidelines. Two reviewers independently screened papers for inclusion and identified studies featuring perioperative complications and outcomes of primary TKA for tibial plateau fracture. Weighted means and standard deviations are presented for each outcome. Results Seven articles (105 patients) were eligible for inclusion. All-cause mortality was 4.75 ± 4.85%. The total complication rate was 15.2 ± 17.3%. Regarding outcomes, Knee Society scores were most commonly reported. The average Knee Society Knee Score was 85.6 ± 5.5, while the average Knee Society Function Score was 64.6 ± 13.7. Average range of motion at final follow-up was 107.5 ± 10.0°. Conclusions Primary TKA for select tibial plateau fractures has acceptable clinical outcomes but does not appear to be superior to ORIF. It may be appropriate to treat certain geriatric patients with TKA to allow for early mobilization and reduce the need for reoperation. Other factors may need to be considered in deciding the optimal treatment. Level of evidence Level III.