Accuracy of magnetic resonance imaging for diagnosing hallux valgus

Abstract

Objective: To assess the accuracy of magnetic resonance imaging (MRI) for the diagnosis of hallux valgus using radiography during weight bearing as the gold standard. Materials and Methods: This was a retrospective analysis of all patients undergoing MRI of the foot and radiography of the foot during weight bearing at our institution between January and June of 2015. The hallux valgus angle (HVA) was measured on MRI and radiography. The Wilcoxon signed-rank test and simple linear regression were used in order to compare measurements. Patients were divided into two groups according to the HVA determined on radiography: > 15° (hallux valgus) and ≤ 15° (control). Qualitative and quantitative assessments of MRI scans were performed. For quantitative assessment, receiver operating characteristic curves were used in order to determine the HVA cutoff with the highest accuracy. Results: A total of 66 MRI scans were included, 22 in the hallux valgus group and 44 in the control group. Wilcoxon signed-rank tests indicated a significant difference between the radiography and MRI measurements. Simple linear regression showed a nonlinear relationship between the measurements and values did not present a strong correlation. In comparison with the radiography measurements, MRI with an HVA cutoff of 16.4° exhibited the highest accuracy (86%). The accuracy of the subjective (qualitative) assessment was inferior to the objective assessment (measurement of the HVA). Conclusion: Hallux valgus can be diagnosed by measuring the HVA on MRI, satisfactory accuracy being achieved with an HVA cutoff of 16.4°.

Imaging evaluation of hallux valgus

“…The evaluation of the musculoskeletal system by magnetic resonance imaging (MRI) has been the subject of a series of recent publications in the radiology literature of Brazil (4)(5)(6)(7)(8) . Although MRI is not considered the gold standard for the evaluation of hallux valgus, because MRI scans are not acquired during weight bearing, we agree with Helito et al (9) that MRI could be used for the diagnosis of this condition, given its high prevalence and the frequent unavailability of radiographic studies during weight bearing, as stated in their study published in the previous issue of Radiologia Brasileira. Although the angles have been widely described on radiographs, the MRI measurements of hallux valgus have not been so assessed.…”

“…The data presented by Helito et al (9) support the findings of Heineman et al (1) who demonstrated excellent interobserver agreement for the HVA and for the IMA on radiographs obtained during weight bearing and on MRI. Over the range of values that they tested, MRI was considered a viable imaging modality for diagnosing and assessing the severity of hallux valgus.…”

“…Although the angles have been widely described on radiographs, the MRI measurements of hallux valgus have not been so assessed. In their article, Helito et al (9) stated that the metatarsophalangeal angle (MPA) on MRI, with a cutoff point of 16.4°, can be used in order to diagnose hallux valgus with satisfactory accuracy. The MPA is defined as the angle formed by the intersection of the longitudinal axis of the first metatarsal bone diaphysis and the first proximal phalanx.…”

Magnetic resonance imaging evaluation of common peroneal nerve injury in acute and subacute posterolateral corner lesion: a retrospective study

“…A number of recent studies conducted in Brazil have highlighted the important role that imaging methods play in the evaluation of the musculoskeletal system (36)(37)(38)(39)(40) . In our study, the prevalence of imaging alterations in the CPN was high (36.8-39.4%), and the levels of interobserver and intraobserver agreement for these abnormalities were excellent (Figure 6).…”

Evaluation of variations of the glenoid attachment of the inferior glenohumeral ligament by magnetic resonance arthrography

“…Several recent studies conducted in Brazil have highlighted the importance of using imaging methods for evaluating the musculoskeletal system ( 27 - 31 ) . The anatomy of the glenohumeral ligaments is complex and variable, various patterns having been described in the literature, which makes it difficult to gain a proper understanding of it.…”