Scapula fractures: interobserver reliability of classification and treatment.

OBJECTIVES

There is substantial variation in the classification and management of scapula fractures. The first purpose of this study was to analyze the interobserver reliability of the OTA/AO classification and the New International Classification for Scapula Fractures. The second purpose was to assess the proportion of agreement among orthopaedic surgeons on operative or nonoperative treatment.

DESIGN

Web-based reliability study.

SETTING

Independent orthopaedic surgeons from several countries were invited to classify scapular fractures in an online survey.

PARTICIPANTS

One hundred three orthopaedic surgeons evaluated 35 movies of three-dimensional computerized tomography reconstruction of selected scapular fractures, representing a full spectrum of fracture patterns.

MAIN OUTCOME MEASUREMENTS

Fleiss kappa (κ) was used to assess the reliability of agreement between the surgeons.

RESULTS

The overall agreement on the OTA/AO classification was moderate for the types (A, B, and C, κ = 0.54) with a 71% proportion of rater agreement (PA) and for the 9 groups (A1 to C3, κ = 0.47) with a 57% PA. For the New International Classification, the agreement about the intraarticular extension of the fracture (Fossa (F), κ = 0.79) was substantial and the agreement about a fractured body (Body (B), κ = 0.57) or process was moderate (Process (P), κ = 0.53); however, PAs were more than 81%. The agreement on the treatment recommendation was moderate (κ = 0.57) with a 73% PA.

CONCLUSIONS

The New International Classification was more reliable. Body and process fractures generated more disagreement than intraarticular fractures and need further clear definitions.