Comparison of plain radiography and CT in postoperative evaluation of ankle fractures

Detection of fibular rotational changes in cone beam CT: experimental study in a specimen model

Background

In syndesmotic injuries, incorrect reduction leads to early arthrosis of the ankle joint. Being able to analyze the reduction result is therefore crucial for obtaining an anatomical reduction. Several studies that assess fibular rotation in the incisura have already been published. The aim of the study was to validate measurement methods that use cone beam computed tomography imaging to detect rotational malpositions of the fibula in a standardized specimen model.

Methods

An artificial Maisonneuve injury was created on 16 pairs of fresh-frozen lower legs. Using a stable instrument, rotational malpositions of 5, 10, and 15° internal and external rotation were generated. For each malposition of the fibula, a cone beam computed tomography scan was performed. Subsequently, the malpositions were measured and statistically evaluated with t-tests using two measuring methods: angle (γ) at 10 mm proximal to the tibial joint line and the angle (δ) at 6 mm distal to the talar joint line.

Results

Rotational malpositions of ≥ 10° could be reliably displayed in the 3D images using the measuring method with angle δ. For angle γ significant results could only be displayed for an external rotation malposition of 15°.

Conclusions

Clinically relevant rotational malpositions of the fibula in comparison with an uninjured contralateral side can be reliably detected using intraoperative 3D imaging with a C-arm cone beam computed tomography. This may allow surgeons to achieve better reduction of fibular malpositions in the incisura tibiofibularis.

Postoperative Ankle Imaging, 2022

Postoperative ankle imaging requires knowledge of the underlying surgical techniques, the usefulness of various imaging modalities, as well as an appreciation for the desired clinical outcomes. Surgical procedures discussed in this article are tibiotalar fracture fixation, tibiotalar, subtalar, and tibiotalocalcaneal arthrodesis, total ankle arthroplasty, talar osteochondral lesion repair and grafting, lateral ligamentous repair and reconstruction, and peroneal and Achilles tendon repair and reconstruction. Imaging can play a vital role in determining if the expected outcome has been achieved and identifying complications, with particular emphasis placed on the use of radiographs, computed tomography (including weight-bearing), magnetic resonance imaging, and ultrasonography.

Reliability of Postoperative Radiographies in Ankle Fractures

Background

The accuracy of reduction of ankle fractures using postoperative plain radiographies (x-ray) remains widely controversial. Some authors have demonstrated that postoperative computed tomography (CT) scan can be useful for these patients. In current study, the efficacy of x-rays after fixation of ankle fractures was investigated based on the CT scan findings.

Methods

A total of 73 patients with ankle fractures who were subjected to open reduction internal fixation (ORIF) were enrolled. After surgery, if the reduction was acceptable based on the x-rays according to standard measurements, the patient was referred for CT scanning. Forty four patients were included in the study. Undesirable CT scan findings including malreduction of fragments or articular surfaces, device malpositioning, missed fractures, and undetected intra-articular fragments were documented.

Results

Undesirable CT findings were seen in 25 patients (56.8%). CT scan showed acceptable reduction without device malpositioning in 19 patients. The most prevalent findings in CT images were malreduction and device malpositioning in 17 and 16 patients, respectively. There was no abnormal finding in CT imaging of lateral malleolar fractures. In two thirds of the injured syndesmosis, device malpositioning, and malreduction were detected in CT scan.

Conclusion

Despite acceptable postoperative x-rays, a considerable number of patients with ankle fractures had inappropriate reduction or undesirable findings in their postoperative CT scan. It seems necessary to use CT scan after ORIF of ankle fractures in order to examine the accuracy of reduction. Further validation of postoperative CT scan in ankle fracture surgery should be investigated.

Comparison of X-Ray Imaging and Computed Tomography Scan in the Evaluation of Knee Trauma

Background and objectives: The aim of the study was to compare the accuracy of X-ray (XR) imaging according to computed tomography (CT) scanning in the diagnosis of knee bone fractures, and in the determination of fracture characteristics, and to identify CT scan indications in patients with knee trauma. Materials and methods: The patients who presented to the emergency department (ED) due to knee trauma between January 2017 and December 2018 and who underwent XR imaging and CT scans were included in the study. XR images were reinterpreted by an emergency physician. The official reports, which had been interpreted by a radiologist in the hospital automation system for CT images, were considered valid. Results: Five hundred and forty-eight patients were included in the study. Of the patients, 200 (36.5%) had fractures in XR imaging and 208 (38.0%) had fractures in CT scans. Compared to CT scanning, XR imaging was found to have 89% sensitivity, 95% specificity, 92% positive predictive value, and 92% negative predictive value in identifying the fracture. The sensitivity of XR imaging in identifying growth plate fracture, angulation, stepping off, and extension of the fracture into the joint space was determined as 78% and less. According to the kappa value, there was determined a perfect concordance between the XR imaging and CT scans in angulation, stepping off, and extension of the fracture into the joint space. This concordance was moderate in growth plate fractures. Conclusions: XR imaging has a low sensitivity in identifying knee fractures. There is a moderate concordance between XR imaging and CT scanning in identifying growth plate fractures. Therefore, CT scanning should be performed in patients whose fracture type and fracture characteristics are not able to be determined exactly with XR imaging in knee injury.

Comparison of Open Reduction and Internal Fixation Versus Closed Reduction and Percutaneous Fixation for Medial Malleolus Fractures

Introduction

Surgical treatment of medial malleolus (MM) fractures can be performed through open or percutaneous approaches, although comparisons between these two approaches have not been undertaken. In this study, we compared patients with MM fractures treated with closed reduction and percutaneous fixation (CRPF) with patients treated with traditional open reduction and internal fixation (ORIF).

Methods

A group of 165 consecutive patients underwent surgical fixation of a closed MM fracture from 2011 to 2015 at a single institution. Thirty-one underwent CRPF and 134 underwent ORIF. Patient demographics, injury characteristics, treatment methods, and outcome variables were recorded through review of patient charts, radiographs, and surgical reports.

Results

The rate of MM fracture comminution was higher in the ORIF group compared with the CRPF group (9.7% vs 27.6%; P = 0.04). All other patient and injury variables were similar between the two groups. There was no statistically significant difference observed between the CRPF and ORIF groups regarding outcomes, including nonunion, malunion, time to union, rate of hardware removal, and wound complications.

Discussion

Both CRPF and ORIF resulted in acceptable radiographic outcomes and low complication rates for the treatment of MM fractures.