Distinction of scaphoid proximal pole fractures from waist fractures is important for management, but it is unclear if the distinction is reliable. However, evidence from our study showed that proximal pole fractures are sufficiently distinct from proximal waist fractures such that a CT does not improve the reliability of diagnosis (1). It was also found that radiographs are reliable in distinction of nonunions from acute fractures of the scaphoid waist without computed tomography (2). 

Six-week follow-up radiographs are a common reference standard for the diagnosis of suspected scaphoid fractures. The main purpose of another study was to evaluate the inter-observer reliability and diagnostic performance characteristics of 6-weeks radiographs for the detection of scaphoid fractures. In addition, two online techniques for evaluating radiographs were compared. Due to low agreement between observers for the recognition of scaphoid fractures and poor diagnostic performance, 6-week radiographs are not adequate for evaluating suspected scaphoid fractures (3). The online evaluation of radiographs using a DICOM viewer seems to improve diagnostic performance characteristics compared to static JPEG images, and future reliability and diagnostic studies should account for variation due to the method of delivering medical images.

We also measured the diagnostic performance characteristics and reliability of 2-dimensional (2DCT) and 3-dimensional (3DCT) computed tomography images and modeling of coronoid fractures. It was found that more sophisticated images and modeling improved inter-observer reliability but not accuracy when characterizing coronoid fractures (4).

In contrast to the previously mentioned studies, it was found that simplifying proximal humeral fracture classifications did not improve inter-observer reliability (5). However, training observers improved inter-observer reliability of a simple proximal humeral fracture classification system among surgeons from the United States and, in particular, younger and less-specialized surgeons. This finding may suggest that our interpretations of radiographic information might become more fixed and immutable with experience.

A study of the reliability of classification of proximal femur fractures found that inter-observer reliability was greatest when classifying the fractures into AO Type, rather than Group or Subgroup (6). This finding was independent of surgeon experience and supports the growing body of evidence that relatively simple distinctions are more reliable.

References 

1. Beks RB, Drijkoningen T, Claessen F, Guitton TG, Ring D; Science of Variation Group. Interobserver Variability of the Diagnosis of Scaphoid Proximal Pole Fractures. J Wrist Surg. 2018 Sep;7(4):350-354. doi: 10.1055/s-0038-1641716. Epub 2018 Apr 10. PubMed PMID: 30174995; PubMed Central PMCID: PMC6117179.
2. Drijkoningen T, Guitton TG, Ring D. Plain radiographs are reliable in distinction of nonunions from acute fractures of the scaphoid waist without computed tomography. J Hand Surg Eur Vol. 2018 Aug 27:1753193418794862. doi: 10.1177/1753193418794862. [Epub ahead of print] PubMed PMID: 30149776.
3. Mallee WH, Mellema JJ, Guitton TG, Goslings JC, Ring D, Doornberg JN; Science of Variation Group. 6-week radiographs unsuitable for diagnosis of suspected scaphoid fractures. Arch Orthop Trauma Surg. 2016 Jun;136(6):771-8. Doi: 10.1007/s00402-016-2438-4. Epub 2016 Mar 30. Erratum in: Arch Orthop Trauma Surg. 2017 May;137(5):733. PubMed PMID: 27026536; PubMed Central PMCID: PMC4870290.
4. Guitton TG, Kinaci A, Ring D. Diagnostic accuracy of 2- and 3-dimensional computed tomography and solid modeling of coronoid fractures. J Shoulder Elbow Surg. 2013 Jun;22(6):782-6. doi: 10.1016/j.jse.2013.02.009. Epub 2013 Apr 14. PubMed PMID: 23594717.
5. Mellema JJ, Kuntz MT, Guitton TG, Ring D. The Effect of Two Factors on Interobserver Reliability for Proximal Humeral Fractures. J Am Acad Orthop Surg. 2016 Nov 30. [Epub ahead of print] PubMed PMID: 27906770.
6. Crijns TJ, Janssen SJ, Davis JT, Ring D, Sanchez HB; Science of Variation Group. Reliability of the classification of proximal femur fractures: Does clinical experience matter? Injury. 2018 Mar 14. pii: S0020-1383(18)30082-2. doi:10.1016/j.injury.2018.02.023. [Epub ahead of print] PubMed PMID: 29549969.