[Incidence of distal ulna fractures associated with distal radius fractures: Treatment options]

MDCT evaluation of distal radius fractures and their association with carpal and distal ulnar fractures

PURPOSE

The purpose of this study was to evaluate the characteristics of distal radius fractures (DRFs) in patients undergoing multi-detector computed tomography (MDCT) and their association with carpal and distal ulnar fractures.

METHODS

This retrospective study analyzed 120 patients, who underwent MDCT for evaluation of DRFs. Two radiologists independently evaluated the data for various fracture characteristics and for associated carpal and distal ulnar fractures.

RESULTS

Out of 120 DRFs, 74 were complete articular, 40 were partial articular and only 6 were extra-articular. Displacement was present in 99 fractures and intra-articular step off was present in 73 fractures. A total of 81 carpal bone fractures were identified in 46 (38.3%) patients, with more than one carpal bone fracture in 21 patients. Distal ulnar fractures were detected in 79 patients (65.8%), out of which 67 involved the ulnar styloid. DRFs with intra-articular step off were more frequently associated with carpal bone fracture (p value: 0.021), while displaced DRFs were more frequently associated with distal ulnar fracture (p value <0.001). Interobserver agreement for detection of carpal bone fractures (κ = 0.807) and distal ulnar fractures (κ = 0.923) was excellent.

CONCLUSION

Majority of DRFs in patients referred for MDCT were complete articular with high incidence of displacement and intra-articular step off. Associated carpal bone and distal ulna fractures were not uncommon.

Poor reliability and reproducibility of 3 different radiographical classification systems for distal ulna fractures

BACKGROUND AND PURPOSE

Classification of fractures can be valuable for research purposes but also in clinical work. Especially with  are fractures, such as distal ulna fractures, a treatment algorithm based on a classification can be helpful. We compared 3 different  classification systems of distal ulna fractures and investigated their reliability and reproducibility.

PATIENTS AND METHODS

patients with 97 fractures of the distal ulna, excluding the ulnar styloid, were included. All fractures were  independently classified by 3 observers according to the classification by Biyani, AO/OTA 2007, and AO/OTA 2018. The classification process was repeated after a minimum of 3 weeks. We used Kappa value analysis to determine inter- and intra-rater agreement.

RESULTS

The inter-rater agreement of the AO/OTA 2007 classification was judged as fair, ĸ 0.40, whereas the agreement of AO/OTA 2018 and Biyani was moderate at ĸ 0.42 and 0.43 respectively. The intra-rater agreement was judged as moderate for all classifications.

INTERPRETATION

The differences between the classifications were small and the overall impression was that neither of them was good enough to be of substantial clinical value. The Biyani classification, being developed specifically for distal ulna fractures, was the easiest and most fitting for the fracture patterns seen in our material, but lacking options for fractures of the distal diaphysis. Standard radiographs were considered insufficient for an accurate classification. A better radiographic method combined with a revised classification might improve accuracy, reliability, and reproducibility.

Incidence of distal ulna fractures in a Swedish county: 74/100,000 person-years, most of them treated non-operatively

Background and purpose - Fractures of the distal ulna can occur in isolation or in conjunction with a distal radius fracture. They may result in incongruence and instability of the distal radioulnar joint. We investigated the incidence of distal ulna fractures, whether any fracture types were more common, and the methods of treatment used.Patients and methods - Data were collected from patients 18 years or older, treated for a fracture of the distal ulna in Östergötland, Sweden, during 2010-2012. Patients were identified in the patient registry. The fractures were classified according to the AO comprehensive classification of fractures.Results - The incidence of distal ulna fractures was 74/100,000 person-years. The most common fracture type was that of the ulnar styloid Q1 (79%), followed by the ulnar neck Q2 (11%). Rarest was ulna head fracture, type Q4 (1%). Incidental findings were a mean age of 63 years (SD 18), a concomitant distal radius fracture in 92% of the patients and that 79% were caused by falling from standing height. Internal fixation was performed in 30% of the Q2-Q6 fractures. This indicates that most were considered stable without internal fixation or stable after fixation of a concomitant radius fracture.Interpretation - Our results show that fractures of the distal ulna are not very common, and some fracture types are even rare. There seem to be no consensus on treatment.