Inter- and intraobserver agreement of three classification systems for lateral clavicle fractures – reliability comparison between two specialist groups

Abstract

BackgroundAlthough of great value in the management of lateral clavicle fractures, substantial variation in their classification exists. We performed a retrospective study to address the inter- and intraobserver reliability of three different classification systems for lateral clavicle fractures.MethodsRadiographs of 20 lateral clavicle fractures that represented a full spectrum of adult fracture patterns were graded by five experienced radiologists and five experienced trauma surgeons according to the Orthopaedic Trauma Association (OTA), the Neer, and the Jäger/Breitner classification systems. This evaluation was performed at two different time points separated by 3 months. To measure the observer agreement, the Fleiss kappa coefficient (κ) was applied and assessed according to the grading of Landis and Koch.ResultsThe overall interobserver reliability showed a fair agreement in all three classification systems. For the OTA classification system, the interobserver agreement showed a mean kappa value of 0.338 ranging from 0.350 (radiologists) to 0.374 (trauma surgeons). Kappa values of the interobserver agreement for the Neer classification system ranged from 0.238 (trauma surgeons) to 0.276 (radiologists) with a mean κ of 0.278. The Jäger/Breitner classification system demonstrated a mean kappa value of 0.330 ranging from 0.306 (trauma surgeons) to 0.382 (radiologists).The overall intraobserver reliability was moderate for the OTA and the Jäger/Breitner classification systems, while the overall intraobserver reliability for the Neer classification system was fair.The kappa values of the intraobserver agreements showed, in all classification systems, a wide range with the OTA classification system ranging from 0.086 to 0.634, the Neer classification system ranging from 0.137 to 0.448, and a range from 0.154 to 0.625 of the Jäger/Breitner classification system.ConclusionsThe low inter- and intraobserver agreement levels exhibited in all three classification systems by both specialist groups suggest that the tested lateral clavicle fracture classification systems are unreliable and, therefore, of limited value. We should recognize there is considerable inconsistency in how physicians classify lateral clavicle fractures and therefore any conclusions based on these classifications should be recognized as being somewhat subjective.

The Management of Distal Clavicle Fractures – A Survey of UK Shoulder and Elbow Surgeons

“…These fracture configurations are considered unstable and have historically been managed surgically due to the increased risk of non-union and associated functional limitations if managed conservatively [ 3 ]. However, only a fair level of inter-rater agreement has been reported for the modified Neer classification, with many fracture configurations not fitting into discrete classes [ 2 , 12 ]. Therefore, its clinical utility is unclear.…”

Monopolar and Bipolar Combination Injuries of the Clavicle: Retrospective Incidence Analysis and Proposal of a New Classification System

“…On the other hand, current studies show that, depending on the diagnosis, a misjudgment is also possible in the classification of ACJD or LCF, both as under-or over-grading [64,65]. It remains to be mentioned that due to a considerable inconsistency in physicians' classifications, clavicle fracture classification systems in general have previously been unreliable and, therefore, of limited value [65]. This fundamental doubt as to whether newer classification systems would fare any better cannot be dispelled without further studies [47].…”

“…In our opinion, CCIs with mild and incomplete CJIs play a subordinate role, as they did not lead to complete instability from a functional point of view. On the other hand, current studies show that, depending on the diagnosis, a misjudgment is also possible in the classification of ACJD or LCF, both as under-or over-grading [64,65]. It remains to be mentioned that due to a considerable inconsistency in physicians' classifications, clavicle fracture classification systems in general have previously been unreliable and, therefore, of limited value [65].…”

Coracoclavicular fixation techniques for Neer IIb and ‘extra-lateral’ fractures of the distal clavicle: A systematic review

“…33 Similarly, Raurer et al found low inter-and intra-observer agreement levels exhibited in all three classification systems that were studied (Neer, OTA, Jäger/Breitner), by two specialist groups (surgeons and radiologists), suggesting that all such classification systems are far from perfect and, arguably, of limited value. 34 More recently though, Cho et al suggested a new classification system that considers both fracture displacement and stability, in addition to fracture location. 5 This classification system showed moderate interobserver (ĸ = 0.434) and substantial intra-observer (ĸ = 0.644) reliability, while also it is designed to guide surgeons in choosing the most appropriate treatment option and implant type for each type of fracture; for example, coracoclavicular or transacromial fixation for extra-lateral IIc fractures.…”