The Amsterdam wrist rules: The multicenter prospective derivation and external validation of a clinical decision rule for the use of radiography in acute wrist trauma

Background: Although only 39 % of patients with wrist trauma have sustained a fracture, the majority of patients is routinely referred for radiography. The purpose of this study was to derive and externally validate a clinical decision rule that selects patients with acute wrist trauma in the Emergency Department (ED) for radiography. Methods: This multicenter prospective study consisted of three components: (1) derivation of a clinical prediction model for detecting wrist fractures in patients following wrist trauma; (2) external validation of this model; and (3) design of a clinical decision rule. The study was conducted in the EDs of five Dutch hospitals: one academic hospital (derivation cohort) and four regional hospitals (external validation cohort). We included all adult patients with acute wrist trauma. The main outcome was fracture of the wrist (distal radius, distal ulna or carpal bones) diagnosed on conventional X-rays. Results: A total of 882 patients were analyzed; 487 in the derivation cohort and 395 in the validation cohort. We derived a clinical prediction model with eight variables: age; sex, swelling of the wrist; swelling of the anatomical snuffbox, visible deformation; distal radius tender to palpation; pain on radial deviation and painful axial compression of the thumb. The Area Under the Curve at external validation of this model was 0.81 (95 % CI: 0.77-0.85). The sensitivity and specificity of the Amsterdam Wrist Rules (AWR) in the external validation cohort were 98 % (95 % CI: 95-99 %) and 21 % (95 % CI: 15 %-28). The negative predictive value was 90 % (95 % CI: 81-99 %). Conclusions: The Amsterdam Wrist Rules is a clinical prediction rule with a high sensitivity and negative predictive value for fractures of the wrist. Although external validation showed low specificity and 100 % sensitivity could not be achieved, the Amsterdam Wrist Rules can provide physicians in the Emergency Department with a useful screening tool to select patients with acute wrist trauma for radiography. The upcoming implementation study will further reveal the impact of the Amsterdam Wrist Rules on the anticipated reduction of X-rays requested, missed fractures, Emergency Department waiting times and health care costs. Trial registration: This study was registered in the Dutch Trial Registry, reference number NTR2544 on October 1st, 2010

A clinical decision rule for the use of plain radiography in children after acute wrist injury: development and external validation of the Amsterdam Pediatric Wrist Rules

Background: In most hospitals, children with acute wrist trauma are routinely referred for radiography. Objective: To develop and validate a clinical decision rule to decide whether radiography in children with wrist trauma is required. Materials and methods: We prospectively developed and validated a clinical decision rule in two study populations. All children who presented in the emergency department of four hospitals with pain following wrist trauma were included and evaluated for 18 clinical variables. The outcome was a wrist fracture diagnosed by plain radiography. Results: Included in the study were 787 children. The prediction model consisted of six variables: age, swelling of the distal radius, visible deformation, distal radius tender to palpation, anatomical snuffbox tender to palpation, and painful or abnormal supination. The model showed an area under the receiver operator characteristics curve of 0.79 (95% CI: 0.76-0.83). The sensitivity and specificity were 95.9% and 37.3%, respectively. The use of this model would have resulted in a 22% absolute reduction of radiographic examinations. In a validation study, 7/170 fractures (4.1%, 95% CI: 1.7-8.3%) would have been missed using the decision model. Conclusion: The decision model may be a valuable tool to decide whether radiography in children after wrist trauma is required

Incidence and characteristics of distal radial fractures in an urban population in The Netherlands

The increasing incidence of distal radius fracture is thought to be due to the aging population. Surprisingly, some authors have reported a decrease in the incidence of distal radius fracture. Moreover, the type-specific incidence of distal radial fracture classified according to fracture severity is not well documented. The aim of this population-based study was to estimate the overall and type-specific incidences of distal radius fracture in a urban population in The Netherlands. During 2009, all persons aged ≥18 years old with an acute distal radius fracture in two hospitals in The Netherlands were prospectively registered. In 2009, the mid-year study population consisted of 245,559 inhabitants ≥18 years old. Fractures were categorized according to the AO classification. 494 patients with acute distal radius fractures were registered in the two participating hospitals during the 1-year study period. The overall incidence of distal radius fracture was 20 per 10,000 person-years. Among women, the incidence rate increased from the age of 50 and reached a peak of 124 per 10,000 person-years in women 80 years and older. Among men, the incidence rate was low until the age of 80 years and older, and reached a peak of 24 per 10,000 person-years. The incidence rate among women between 50 and 79 years was 54/10,000 person-years. Extra-articular AO type A fractures were most common among all age groups, comprising 50 % of all fractures (40 % in men and 53 % in women). The overall incidence rate of distal radius fracture was 20 per 10,000 person-years. This incidence increases with age for both women and men. A lower incidence rate among women 50-79 years of age was found than previously reported, which may indicate a declining incidence in this age group. Extra-articular AO type A fractures were the most common fracture type