Validation of the classification of surgically treated acetabular fractures in the Swedish Fracture Register

Objectives To validate the classification of surgically treated acetabular fractures in the Swedish Fracture Register (SFR) and to investigate the intra- and interrater reliability of the Judet-Letournel / AO/OTA classification systems. Methods Surgically treated acetabular fractures were randomly selected from the SFR (n = 132) and 124 fractures were classified independently by three experienced orthopedic pelvic surgeons at two different occasions. A gold standard classification was established for each case after these two sessions or, if necessary, after a discussion session. The gold standard classification was compared to the registered SFR classification to assess the validity of SFR data. Accuracy and intra- and interrater agreement were evaluated using Cohen's kappa with interpretation according to Landis and Koch. Results There was moderate agreement between the established gold standard classification and the SFR (kappa 0.43). The level of agreement differed between classification groups. The intrarater agreement was substantial to almost perfect and interrater agreement was moderate to substantial. Conclusions The accuracy of acetabular fracture classifications in the SFR was moderate and comparable to previous validation studies from the SFR on other fracture types. As the accuracy differed between fracture groups, care should be taken when analyzing data from the SFR on specific acetabular fracture groups

Acetabular fractures : Epidemiology and mortality based on 2,132 fractures from the Swedish Fracture Register

AIMS: To describe the epidemiology of acetabular fractures including patient characteristics, injury mechanisms, fracture patterns, treatment, and mortality. METHODS: We retrieved information from the Swedish Fracture Register (SFR) on all patients with acetabular fractures, of the native hip joint in the adult skeleton, sustained between 2014 and 2020. Study variables included patient age, sex, injury date, injury mechanism, fracture classification, treatment, and mortality. RESULTS: In total, 2,132 patients with acetabular fractures from the SFR were included in the study. The majority of the patients were male (62%) and aged over 70 years old (62%). For patients aged > 70 years, the 30-day mortality was 8% and one-year mortality 24%. For patients aged ≤ 70 years, the 30-day mortality was 0.2% and one-year mortality 2%. Low-energy injuries (63%) and anterior wall fractures (20%) were most common. Treatment was most often non-surgical (75%). CONCLUSION: The majority of patients who sustain an acetabular fracture are elderly (> 70 years), of male sex, and the fracture most commonly occurs after a simple, low-energy fall. Non-surgical treatment is chosen in the majority of acetabular fracture patients. The one-year mortality for elderly patients with acetabular fracture is similar to the mortality after hip fracture, and a similar multidisciplinary approach to care for these patients should be considered