• Diagnostic imaging
• Fracture dislocation
• Fracture fixation
• Intra-articular fracture
• Key fragments

• Radius Fractures/classification
• Radius Fractures/diagnostic imaging
• Radius Fractures/surgery
• Humans
• Tomography, X-Ray Computed
• Wrist Injuries/classification
• Wrist Injuries/diagnostic imaging
• Wrist Injuries/diagnosis
• Wrist Fractures

• Adult
• Humans
• Cone-Beam Computed Tomography
• Radius Fractures
• Tomography, X-Ray Computed
• Consensus
• Imaging, Three-Dimensional
• Wrist Fractures

• Distal radioulnar joint
• Distal radius fracture
• Fracture classification system
• Interobserver reliability

• Cone-Beam Computed Tomography/methods
• Finger Injuries/diagnosis
• Finger Injuries/diagnostic imaging
• Fractures, Bone/diagnosis
• Fractures, Bone/diagnostic imaging
• Humans
• Multidetector Computed Tomography/methods
• Phantoms, Imaging
• Radiation Dosage
• Radiography/methods

• Distal radius fractures
• Epidemiology
• Fracture severity
• Treatment

To evaluate the reliability of pronator quadratus fat pad sign to detect distal radius fracture and to predict its severity.

Retrospectively we identified 89 consecutive patients (41 female, mean age 49 ± 18 years) who had X-ray (CR) and computed tomography (CT) within 24 h following distal forearm trauma. Thickness of pronator quadratus fat pad complex (PQC) was measured using lateral views (CR) and sagittal reconstructions (CT). Pearson’s test was used to determine the correlation of the PQC thickness in CR and CT. A positive pronator quadratus sign (PQS) was defined as a PQC > 8.0 mm (female) or > 9.0 mm (male). Frykman classification was utilized to assess the severity of fractures.

Forty-four/89 patients (49%) had a distal radius fracture (Frykman I n = 3, II n = 0, III n = 10, IV n = 5, V n = 2, VI n = 2, VII n = 9, VIII n = 13). Mean thickness of the PQC thickness can reliably be measured on X-ray views and was 7.5 ± 2.8 mm in lateral views (CR), respectively 9.4 ± 3.0 mm in sagittal reconstructions (CT), resulting in a significant correlation coefficient of 0.795. A positive PQS at CR was present in 21/44 patients (48%) with distal radius fracture and in 2/45 patients (4%) without distal radius fracture, resulting in a specificity of 96% and a sensitivity of 48% for the detection of distal radius fractures. There was no correlation between thickness of the PQC and severity of distal radius fractures.

A positive PQS shows high specificity but low sensitivity for detection of distal radius fractures. The PQC thickness cannot predict the severity of distal radius fractures.

• Pronator quadratus fat pad sign
• Pronator quadratus complex
• Distal radius fracture
• Frykman classification
• Conventional radiograph
• Computed tomography

Introduction: The aim of the present study is to develop a heuristic that could replace the surgeon’s analysis for the decision on the operative approach of distal radius fractures based on simple fracture characteristics.

Patients and methods: Five hundred distal radius fractures operated between 2011 and 2014 were analyzed for the surgeon’s decision on the approach used. The 500 distal radius fractures were treated with open reduction and internal fixation through palmar, dorsal, and dorsopalmar approaches with 2.4 mm locking plates or underwent percutaneous fixation. The parameters that should replace the surgeon’s analysis were the fractured palmar cortex, and the frontal and the sagittal split of the articular surface of the distal radius.

Results: The palmar approach was used for 422 (84.4%) fractures, the dorsal approach for 39 (7.8%), and the combined dorsopalmar approach for 30 (6.0%). Nine (1.8%) fractures were treated percutaneously. The correlation between the fractured palmar cortex and the used palmar approach was moderate (r=0.464; p<0.0001). The correlation between the frontal split and the dorsal approach, including the dorsopalmar approach, was strong (r=0.715; p<0.0001). The sagittal split had only a weak correlation for the dorsal and dorsopalmar approach (r=0.300; p<0.0001).

Discussion: The study shows that the surgical decision on the preferred approach is dictated through two simple factors, even in the case of complex fractures.

Conclusion: When the palmar cortex is displaced in distal radius fractures, a palmar approach should be used. When there is a displaced frontal split of the articular surface, a dorsal approach should be used. When both are present, a dorsopalmar approach should be used. These two simple parameters could replace the surgeon’s analysis for the surgical approach.

• distal radius fracture
• fracture classification
• heuristics
• surgical approach

There are no clear guidelines when an additional CT scan should be obtained for the treatment of displaced intra-articular distal radius fractures (DRF). This study aimed to investigate whether surgeons can predict the usefulness of CT scans to facilitate choice of treatment plan and/or pre-operative planning for DRF. Four surgeons evaluated 51 patients with displaced DRF. The choice of treatment (operative or nonoperative) was based on conventional radiographs. Subsequently, the surgeons were asked whether they would have requested an additional CT scan to determine this treatment choice, and also whether they required a CT scan for pre-operative planning. After 4 weeks, the additional CT scan was provided and the cases were assessed again. Based on these data, we calculated the number needed to scan (NNS) and number needed to harm (NNH) for two decision models. Model 1: Only provide a CT scan if the surgeon requested one based on their judgment of the X-rays. Model 2: CT scans for all displaced intra-articular DRF. For choice of treatment, the NNS was lower for model 1 than for model 2 (2.6 vs. 4.3) and the NNH is higher for model 1 (3.1 vs. 1.3). For pre-operative planning, the NNS (1.3 vs. 1.4) and NNH (3.7 vs. 3.4) were comparable for both models. Surgeons are able to predict the usefulness of an additional CT scan for intra-articular displaced DRF for OR indication. However, for pre-operative planning the usefulness of a CT scan is much harder to predict.

• CT scans
• Clinical decision making
• Distal radius fractures

• Adult
• Carpal Bones/diagnostic imaging
• Cone-Beam Computed Tomography/methods
• Cone-Beam Computed Tomography/standards
• Fractures, Malunited/diagnostic imaging
• Humans
• Multidetector Computed Tomography/methods
• Multidetector Computed Tomography/standards
• Radiation Dosage
• Radiography/methods
• Radiography/standards
• Radius Fractures/diagnostic imaging
• Reproducibility of Results
• Sensitivity and Specificity
• Ulna Fractures/diagnostic imaging
• Wrist/diagnostic imaging
• Wrist Injuries/diagnostic imaging

• Deutsche Krebshilfe

Current studies on the additional benefit of using computed tomography (CT) in order to evaluate the surgeons’ agreement on treatment plans for fracture are inconsistent. This inconsistency can be explained by a methodological phenomenon called ‘spectrum bias’, defined as the bias inherent when investigators choose a population lacking therapeutic uncertainty for evaluation. The aim of the study is to determine the influence of spectrum bias on the intra-observer agreement of treatment plans for fractures of the distal radius.

Four surgeons evaluated 51 patients with displaced fractures of the distal radius at four time points: T1 and T2: conventional radiographs; T3 and T4: radiographs and additional CT scan (radiograph and CT). Choice of treatment plan (operative or non-operative) and therapeutic certainty (five-point scale: very uncertain to very certain) were rated. To determine the influence of spectrum bias, the intra-observer agreement was analysed, using Kappa statistics, for each degree of therapeutic certainty.

In cases with high therapeutic certainty, intra-observer agreement based on radiograph was almost perfect (0.86 to 0.90), but decreased to moderate based on a radiograph and CT (0.47 to 0.60). In cases with high therapeutic uncertainty, intra-observer agreement was slight at best (-0.12 to 0.19), but increased to moderate based on the radiograph and CT (0.56 to 0.57).

Spectrum bias influenced the outcome of this agreement study on treatment plans. An additional CT scan improves the intra-observer agreement on treatment plans for a fracture of the distal radius only when there is therapeutic uncertainty. Reporting and analysing intra-observer agreement based on the surgeon’s level of certainty is an appropriate method to minimise spectrum bias.

Cite this article: Bone Joint Res 2015;4:190–194.

• Agreement study
• computed tomography
• distal radial fracture
• intraobserver
• spectrum bias

• Arthroscopy/instrumentation
• Arthroscopy/methods
• Fracture Fixation, Internal/instrumentation
• Fracture Fixation, Internal/methods
• Fractures, Bone/surgery
• Humans
• Radius Fractures/surgery
• Wrist Injuries/surgery

• Area Under Curve
• Cadaver
• Carpal Bones/diagnostic imaging
• Humans
• ROC Curve
• Radiography/instrumentation
• Radiography/methods
• Radius Fractures/classification
• Radius Fractures/diagnostic imaging
• Ulna Fractures/diagnostic imaging
• X-Ray Intensifying Screens

• Artificial Intelligence
• Emergency Service, Hospital
• Humans
• Imaging, Three-Dimensional
• Multiple Trauma/classification
• Multiple Trauma/diagnostic imaging
• Musculoskeletal System/diagnostic imaging
• Musculoskeletal System/injuries
• Radiation Dosage
• Radiographic Image Enhancement/methods
• Radiographic Image Interpretation, Computer-Assisted/methods
• Tomography, Spiral Computed
• Tomography, X-Ray Computed/methods
• Tomography, X-Ray Computed/standards