ORCID Profile
0000-0001-9406-5232
Current Organisation
University of Toronto
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Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2014
Publisher: SLACK, Inc.
Date: 09-2017
DOI: 10.3928/01477447-20170907-01
Abstract: Daily administration of vitamin D is important for maintaining bone homeostasis. The orthopedic community has shown increased interest in vitamin D supplementation and patient outcomes after fracture. The current study used data from a large hip fracture trial to determine the proportion of patients who consistently used vitamin D after hip fracture surgery and to determine whether supplementation was associated with improved health-related quality of life and reduced reoperation rates. The FAITH study is a multicenter trial of elderly patients with femoral neck fracture treated with internal fixation. The current study asked a subset of patients included in the FAITH study about vitamin D supplementation and categorized them as consistent users, inconsistent users, or nonusers. This study also evaluated whether supplementation was associated with improved quality of life and reduced reoperation rates. The final analysis included 573 patients (mean age, 74.1 years female, 66.3% nondis-placed fractures, 72.4%). A total of 18.7% of participants reported no use of vitamin D, 35.6% reported inconsistent use, and 45.7% reported consistent use. Adjusted analysis found that consistent supplementation was associated with a 2.42 increase of the Short Form-12 physical component score 12 months postoperatively ( P =.033). However, supplementation was not associated with reduced reoperation rates ( P =.386). Despite guidelines recommending vitamin D supplementation, a low proportion of elderly patients with hip fracture use vitamin D consistently, suggesting a need for additional strategies to promote compliance. This study found that the use of vitamin D was associated with a statistically significant but not clinically significant improvement in health-related quality of life after hip fracture. Further research is needed to confirm these findings. [ Orthopedics. 2017 40(5):e868–e875.]
Publisher: Springer Science and Business Media LLC
Date: 27-09-2013
DOI: 10.1007/S00198-013-2487-2
Abstract: The study rationale was to provide a detailed overview of the costs for femoral neck fracture treatment with internal fixation in the Netherlands. Mean total costs per patient at 2-years follow-up were 19,425. Costs were higher for older, less healthy patients. Results are comparable to internationally published costs. The aim of this study was to provide a detailed overview of the cost and healthcare consumption of patients treated for a hip fracture with internal fixation. A secondary aim was to compare costs of patients who underwent a revision surgery with patients who did not. The study was performed alongside the Dutch s le of an international randomized controlled trial, concerning femoral neck fracture patients treated with internal fixation. Patient characteristics and healthcare consumption were collected. Total follow-up was 2 years. A societal perspective was adopted. Costs included hospital costs during primary stay and follow-up, and costs related to rehabilitation and changes in living situation. Costs were compared between non-revision surgery patients, implant removal patients, and revision arthroplasty patients. A total of 248 patients were included (mean age 71 years). Mean total costs per patient at 2-years follow-up were 19,425. In the non-revision surgery patients total costs were 17,405 (N = 137), in the implant removal patients 10,066 (N = 38), and in the revision arthroplasty patients 26,733 (N = 67). The main contributing costs were related to the primary surgery, admission days, physical therapy, and revision surgeries. The main determinant was the costs of admission to a rehabilitation center/nursing home. Costs were specifically high in elderly with comorbidity, who were less independent pre-fracture, and have a longer admission to the hospital and/or a nursing home. Costs were also higher in revision surgery patients. The 2-years follow-up costs in our study were comparable to published costs in other Western societies.
Publisher: SLACK, Inc.
Date: 07-2013
DOI: 10.3928/01477447-20130624-13
Abstract: This study assesses femoral neck shortening and its effect on gait pattern and muscle strength in patients with femoral neck fractures treated with internal fixation. Seventy-six patients from a multicenter randomized controlled trial participated. Patient characteristics and Short Form 12 and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were collected. Femoral neck shortening, gait parameters, and maximum isometric forces of the hip muscles were measured and differences between the fractured and contralateral leg were calculated. Variables of patients with little or no shortening, moderate shortening, and severe shortening were compared using univariate and multivariate analyses. Median femoral neck shortening was 1.1 cm. Subtle changes in gait pattern, reduced gait velocity, and reduced abductor muscle strength were observed. Age, weight, and Pauwels classification were risk factors for femoral neck shortening. Femoral neck shortening decreased gait velocity and seemed to impair gait symmetry and physical functioning. In conclusion, internal fixation of femoral neck fractures results in permanent physical limitations. The relatively young and healthy patients in our study seem capable of compensating. Attention should be paid to femoral neck shortening and proper correction with a heel lift, as inadequate correction may cause physical complaints and influence outcome.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2018
DOI: 10.1097/BOT.0000000000001162
Abstract: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25–2.50 P = 0.001], higher body mass index (for every 5-point increase) (HR 1.19, 95% CI 1.02–1.39 P = 0.027), displaced fracture (HR 2.16, 95% CI 1.44–3.23 P 0.001), unacceptable quality of implant placement (HR 2.70, 95% CI 1.59–4.55 P 0.001), and smokers treated with cancellous screws versus smokers treated with a sliding hip screw (HR 2.94, 95% CI 1.35–6.25 P = 0.006). Additionally, for every 10-year decrease in age, participants experienced an average increased risk of 39% for hardware removal. Results of this study may inform future research by identifying high-risk patients who may be better treated with arthroplasty and may benefit from adjuncts to care (HR 1.39, 95% CI 1.05–1.85 P = 0.020). Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2009
Publisher: Elsevier BV
Date: 02-2009
DOI: 10.1016/J.JCLINEPI.2008.05.006
Abstract: To devise and test techniques to blind outcome assessors in trials of hip fracture fixation. We developed three techniques (Blackout, Subtraction, and Overlay) to mask radiographs of hip fractures fixated with cancellous screws or dynamic hip screws. Fifty orthopedic trauma surgeons each assessed 32 radiographs blinded with each technique. All techniques achieved low rates of correct identification of screw type (14.9% for Blackout, 26.9% for Subtraction, 22.1% for Overlay) and high proportions of "don't know" responses (72.3%, 48.4%, 52.8%, respectively). The interrater reliability of reduction quality in the blinded images (intraclass correlation coefficient [ICC]=0.55-0.57) was similar to the reliability of the unblinded radiographs (ICC=0.60). Surgeons perceived 6.9% of the Overlay images as much more difficult to rate than unblinded radiographs, compared with 9.7% of Subtraction images (P=0.25) and 28.0% of Blackout images (P<0.001). Three techniques of blinding radiographs of femoral neck fractures successfully mask surgeons to the type of implant fixated, do not compromise reliability of reduction ratings, and do not make rating most radiographs more difficult. Trialists should explore creative approaches to optimize blinding when designing trials, and should incorporate rigorous approaches to testing blinding success.
Publisher: Elsevier BV
Date: 12-2012
DOI: 10.1016/J.INJURY.2012.08.061
Abstract: Patients with hip fractures are older and often present many co-morbidities, including dementia. These patients cannot answer quality of life questionnaires and are generally excluded from trials. We hypothesized that a significant number of patients are being excluded from these studies and this may impact outcomes. This was a two part study the first analyzing databases of two ongoing large-scale multi-centred hip fracture trials and the second being a systematic review. The FAITH and HEALTH studies were analyzed for exclusion incidence directly related to dementia. The second part consisted of a systematic search of all relevant studies within the last 20 years. In the FAITH study, a total of 1690 subjects were excluded, 375 (22.2%) of which were due to dementia or cognitive impairment. In the HEALTH study, 575 were excluded with dementia/cognitive impairment representing 207 patients (36%). Following the systematic review, 251 articles were identified 17 of which were retained. The overall prevalence of dementia was 27.9% (range 2-51%). Only two studies compared demented and non-demented groups. In these studies significant increases in both mortality and complications were found. In summary, when investigating hip fractures, choosing appropriate objective endpoints is essential to ensure results are also applicable to patients with dementia.
Publisher: Springer Science and Business Media LLC
Date: 02-2014
DOI: 10.1007/S00167-014-2835-6
Abstract: The purpose of this study was to estimate the radiographic prevalence of CAM-type femoroacetabular impingement (FAI) in elderly patients (≥ 50 years) who have undergone internal fixation for femoral neck fracture. A total of 187 frog-leg lateral radiographs of elderly patients who underwent internal fixation for a femoral neck fracture were reviewed by two independent reviewers. The alpha angle, beta angle, and femoral head-neck offset ratio were calculated. The presence of two abnormal radiographic parameters was deemed to be diagnostic of radiographic CAM-type impingement. Radiographic CAM-type FAI was identified in 157 out of 187 (84 %) patients who underwent internal fixation for fractures of the femoral neck. Moderate-to-good inter-observer reliability was achieved in the measurement of radiographic parameters. With reference to fracture subtypes and prevalence of radiographic features of CAM-type morphology, 97 (72 %) out of 134 patients were positive for CAM in Garden subtypes I and II, whereas 49 (85.9 %) out of 57 patients had radiographic CAM in Garden III and IV subtypes. There was a high prevalence of CAM-type FAI in patients that underwent surgical fixation of femoral neck fractures. This is significantly higher than the reported prevalence in non-fracture patient populations. The high prevalence of CAM morphology could be related to several factors, including age, fracture morphology, quality of reduction, type of fixation, and fracture healing.
Publisher: Elsevier BV
Date: 02-2020
Publisher: Elsevier BV
Date: 2015
DOI: 10.1016/J.JSE.2014.05.013
Abstract: The factors influencing the decision making of operative treatment for fractures of the proximal humerus are debated. We hypothesized that there is no difference in treatment recommendations between surgeons shown radiographs alone and those shown radiographs and patient information. Secondarily, we addressed (1) factors associated with a recommendation for operative treatment, (2) factors associated with recommendation for arthroplasty, (3) concordance with the recommendations of the treating surgeons, and (4) factors affecting the inter-rater reliability of treatment recommendations. A total of 238 surgeons of the Science of Variation Group rated 40 radiographs of patients with proximal humerus fractures. Participants were randomized to receive information about the patient and mechanism of injury. The response variables included the choice of treatment (operative vs nonoperative) and the percentage of matches with the actual treatment. Participants who received patient information recommended operative treatment less than those who received no information. The patient information that had the greatest influence on treatment recommendations included age (55%) and fracture mechanism (32%). The only other factor associated with a recommendation for operative treatment was region of practice. There was no significant difference between participants who were and were not provided with information regarding agreement with the actual treatment (operative vs nonoperative) provided by the treating surgeon. Patient information-older age in particular-is associated with a higher likelihood of recommending nonoperative treatment than radiographs alone. Clinical information did not improve agreement of the Science of Variation Group with the actual treatment or the generally poor interobserver agreement on treatment recommendations.
Publisher: Elsevier BV
Date: 04-2017
Publisher: Springer Science and Business Media LLC
Date: 08-01-2012
Abstract: Surgeons in the Netherlands, Canada and the US participate in the FAITH trial (Fixation using Alternative Implants for the Treatment of Hip fractures). Dutch sites are managed and visited by a financed central trial coordinator, whereas most Canadian and US sites have local study coordinators and receive per patient payment. This study was aimed to assess how these different trial management strategies affected trial performance. Details related to obtaining ethics approval, time to trial start-up, inclusion, and percentage completed follow-ups were collected for each trial site and compared. Pre-trial screening data were compared with actual inclusion rates. Median trial start-up ranged from 41 days (P25-P75 10-139) in the Netherlands to 232 days (P25-P75 98-423) in Canada (p = 0.027). The inclusion rate was highest in the Netherlands median 1.03 patients (P25-P75 0.43-2.21) per site per month, representing 34.4% of the total eligible population. It was lowest in Canada 0.14 inclusions (P25-P75 0.00-0.28), representing 3.9% of eligible patients (p 0.001). The percentage completed follow-ups was 83% for Canadian and Dutch sites and 70% for US sites (p = 0.217). In this trial, a central financed trial coordinator to manage all trial related tasks in participating sites resulted in better trial progression and a similar follow-up. It is therefore a suitable alternative for appointing these tasks to local research assistants. The central coordinator approach can enable smaller regional hospitals to participate in multicenter randomized controlled trials. Circumstances such as available budget, s le size, and geographical area should however be taken into account when choosing a management strategy. ClinicalTrials.gov: NCT00761813
Publisher: Springer Science and Business Media LLC
Date: 26-06-2014
No related grants have been discovered for Hans Kreder.