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Beate Hanson

Publications and source records attributed to Beate Hanson.

8 recordsLinked to original sources

Issues in the planning and conduct of non-randomised studies.

This paper discusses topics related to the planning and implementation of non-randomised clinical studies in orthopaedics. A well-conducted case-series is appropriate to demonstrate the safety of a surgical intervention. The case-series design involves the provision of a defined intervention to a group of patients with the ultimate objective of describing the final outcome, including such occurrences as complications. There is no alternative procedure serving as a control. The key aspects are to ensure enrolment of all eligible patients and to obtain a sufficiently large sample size to allow precise and valid estimation of complication risks. Targeted complications should be clearly defined and fully documented during a pre-defined follow-up period. Loss to follow-up should be minimised. Comparative studies are required to demonstrate treatment effectiveness. If a randomised controlled trial (RCT) is not feasible, an observational design such as a cohort or a case-control study should be considered. In observational designs, the treatment decision is made by the surgeons. In a case-control study, patients are selected based on their outcomes and their treatment or exposure status is recorded retrospectively. In a cohort study, groups of patients are selected based on their treatment and are followed for outcomes. There are numerous variations. Data can be collected prospectively or retrospectively; comparison groups may be concurrent or non-concurrent, or studied at different locations. The optimal design is tailored to clinical questions and research settings, while keeping in mind the respective methodological strengths and weaknesses of available options. The strength of the observational study is its proximity to daily clinical practice. The limitations are the possibility of numerous biases and confounding factors. Despite many challenges to the internal validity of non-randomised studies in orthopaedics surgery, it is possible to use such designs in order to provide reasonably valid answers to clinically important questions.

Algorithms↗

Clinical studies in spinal surgery.

There is a growing interest in applying evidence-based approaches also in orthopedic surgery. Despite many challenges to the validity of clinical trials in orthopedic surgery, it is possible to conduct well-designed trials in this field and to produce clinically important findings and reasonably valid conclusions about effectiveness, prognosis and diagnosis in orthopedic surgery. We describe the main principles for conducting clinical trials in this field as well as some of the most common errors and ways to avoid them.

Bias↗

Pathways to evidence-based knowledge in orthopaedic surgery: an international survey of AO course participants.

The aim of this study was to gain information about how orthopaedic surgeons use evidence-based literature and how this is influenced by their knowledge of evidence-based medicine. We administered a questionnaire to participants at courses of the Association for the Study of Internal Fixation (AO-ASIF) in Davos, Switzerland, in December 2003. Special attention was paid to the surgeons' educational level, affiliations, and the infrastructure and evidence sources they used. In addition, we tested participants on their knowledge and attitude to evidence-based orthopaedic surgery (EBOS). Of 1,274 course participants, 456 completed the questionnaire. Of 446 respondents, 300 had heard of EBOS, but only 45% could define it correctly. Nearly two thirds identified scientific publications as their main source of scientific knowledge. The respondents' attitudes to and awareness of EBOS principles was high, but it did not influence their manner of searching for scientific information or their trust in various sources of recommendations.

Adult↗

A concept for the validation of fracture classifications.

The fracture classification systems currently used most frequently were not developed or validated by rigorous scientific evaluation methods. This paper discusses the classification of fractures from an epidemiological and clinical decision-making perspective and proposes a standardized methodological concept for their development and scientific validation. Classification categories are clinically relevant entities that surgeons should be able to use for diagnosis with sufficient confidence to limit misclassification and associated treatment errors. The process of validation should assess the value of specific clinical information (eg, the use of radiographs or computed tomography scans) in increasing the probability of a correct diagnosis. A 3-phase validation concept is proposed where: 1) classification categories are defined and the classification process using specific diagnostic images is evaluated by experts in a series of agreement studies (reliability, accuracy, likelihood ratios); 2) a multicenter agreement study is conducted among a representative group of future users of the classification; and 3) the classification proposal is applied in the context of a prospective clinical study to assess its clinical usefulness.

Classification↗

Health-related quality of life following operative treatment of unstable ankle fractures: a prospective observational study.

BACKGROUND: Although Weber type B ankle fractures are often considered benign with a good prognosis, evidence from observational studies suggests that 17% to 24% of such patients may have less satisfactory outcomes. Although the explanation for variability in outcomes remains unclear, previous studies of other surgical procedures have suggested nonsurgery-related causes account for much of the variability in outcomes. METHODS: We conducted a prospective observational cohort study to evaluate health-related quality of life in 30 patients with unstable ankle fractures who were otherwise healthy. Only patients from 2 university-affiliated hospitals sustaining unstable type B Weber injury patterns requiring surgery were eligible. Patients provided detailed baseline information regarding alcohol consumption, smoking habits, and educational level. Patients completed the short form 36 questionnaire and a visual analogue pain scale at regular follow-up intervals. RESULTS: The average patient age was 51.6 years (SD 15.2 years), and 57% (17 out of 30) were male. The majority of fractures were the result of a fall (67%, 20 out of 30), and all were closed injuries. Almost half of all patients were smokers (47%, 14 out of 30), whereas 43% consumed alcohol on a weekly basis (13 out of 30). Forty-three percent of patients (13 out of 30) had obtained an elementary or high school level of education. Patients experienced significant improvements in all domains of the SF-36 questionnaire (P < 0.001), except general health, which remained essentially normal over the 24-month period. Study patients achieved scores similar to age-matched U.S. normative data across 6 of the 8 domains (Role Emotional, Social Function, Mental Health, Bodily Pain, Vitality, and General Health). However, patients' physical function and role physical scores remained significantly lower than US norms at 24 months (21.8 and 20.7 points lower on a 100-point scale, respectively; P < 0.001). Smoking history (P = 0.02), presence of a medial malleolar fracture (P = 0.02), and lower levels of education (P = 0.01) were significant independent predictors of lower physical function up to 3 months postoperation. Lower mental health domain scores were significantly associated with alcohol use (P = 0.02) and increasing age (P = 0.04). CONCLUSIONS: As is the case in many other areas, social factors may be important determinants of outcome in patients with traumatic fractures. Optimal orthopedic care may involve attention to modifiable risk factors, including smoking and alcohol consumption.

Adolescent↗

Operative treatment of extra-articular proximal tibial fractures.

BACKGROUND: Extra-articular proximal tibial fractures are often the result of high-energy trauma with displacement and comminution. Most authors agree that operative management of these fractures is warranted to optimize patient outcomes. It is unclear, however, which surgical option (plate, nail, external fixator, or combination) is preferable. (1-17) OBJECTIVE: To evaluate the effect of alternative operative techniques in the management of extra-articular proximal third tibial fractures on rates of nonunion, malunion, infection, compartment syndrome, and implant failure. HIGHEST AVAILABLE EVIDENCE: 1. Intramedullary nail (level 3 prospective case series). 2. Plates (level 3 prospective case series). 3. External fixator (level 4 case series). STUDY IDENTIFICATION: 1. Cochrane Database: 0 articles. 2. PubMed Search: Proximal tibial fractures: 568 hits; And external fixation: 69 hits; And plate: 103 hits; And intramedullary nail: 77 hits. Clinical queries search: proximal tibial fracture (specificity/therapy): 1 hit; proximal tibial fracture (sensitivity): 24 hits. Systematic reviews: 3 hits (none relevant). 3. OTA website abstract database: 8 abstracts. Total number potentially relevant articles: 29 (following review of all study titles and abstracts). Total number included after review: 17 (1-17) .

Evidence-Based Medicine↗

Current practice in the intramedullary nailing of tibial shaft fractures: an international survey.

BACKGROUND: Tibial fractures are the most common of all long bone fractures. Although many tibial fractures may be managed conservatively, a certain subset, including unstable fractures and open fractures, require operative stabilization. Intramedullary nails have become the popular choice of implant in the treatment of tibial shaft fractures. The variability in outcomes with tibial shaft fractures may reflect technical aspects of the surgical procedure and perioperative care regimens among surgeons. Identifying the distribution of surgeons' preferences in nailing technique, and the rationale for their choices, will aid in focusing educational activities for the orthopedic community and planning future clinical trials. Our objectives were to clarify surgeons' opinions regarding technical aspects of surgery and perioperative care after intramedullary nailing of closed and open tibial shaft fractures, and to identify predictors of surgeons' preferences in technique and perioperative care. METHODS: This study was a cross-sectional survey using focus groups, key informants, and sampling to redundancy strategies to develop a survey to examine surgeons' preferences in the treatment of tibial shaft fractures. The survey was pilot tested for clarity and content validity. We mailed this survey in July 2000 to 577 orthopedic surgeons who have an interest in trauma care. These were members of the Orthopaedic Trauma Association, American Academy of Orthopaedic Surgeons, or European AO International affiliated trauma centers. We used several strategies to improve response rates including personalized cover letters, stamped return envelopes, follow-up telephone calls, and repeat mailing of questionnaires. Main outcome measures included technical issues such as reduction, exposure, intramedullary reaming, and interlocking screws; and factors associated with surgeons' preferences such as age, fellowship, academic practice, and geographic location. RESULTS: Four hundred forty-four surgeons (77%) responded. Sixty percent of respondents had an academic practice, 84% supervised residents, and 65.1% had fellowship training in trauma. Approximately half (51.5%) of surgeons used a tourniquet. The odds that a surgeon in Asia or Africa used tourniquets was 10 times that of a North American surgeon (p = 0.004 and p = 0.002, respectively). Patellar tendon retraction and an inferior-based entry portal was the popular choice among surgeons (70.1% and 70.8%, respectively). Surgeons from Australia (odds ratio [OR] = 50, p < 0.001), South America (OR = 9.0, p < 0.001), Europe (OR = 3.7, p = 0.001), and Asia (OR = 3.8, p = 0.006) were significantly more likely to use a patellar splitting approach compared with North American surgeons. In the perioperative care of open tibial shaft fractures, there was consensus in the use of intravenous antibiotics and wound irrigation (96.5% and 95.6%, respectively). However, we found considerable variability in surgeons' preference in wound irrigation pressures (high, 38.7%; low, 45.4%). Surgeons in South America were 10 times more likely to use low-pressure irrigation than North American surgeons (p = 0.0005). In grade IIIB open tibial shaft fractures, 94% of surgeons believed wound closure should be obtained within the first 7 days after the injury. A surgeon's geographic location was a significant predictor of the timing of soft tissue coverage (p = 0.001). CONCLUSION: Consensus in the use of irrigation and intravenous antibiotics in open fractures was achieved among surgeons. However, there remains considerable variability in the surgical technique of intramedullary nailing, the duration of antibiotic use, and the timing of wound closure in open tibial fracture care. Continued education and large multicenter trials are needed to establish best practice in the operative treatment of tibial shaft fracture.

Adult↗