title: Comparison between Simple Radiographic and Computed Tomographic Three-Dimensional Reconstruction for Evaluation of the Distal Metatarsal Articular Angle.
abstract: The hallux valgus is a pathologic condition in the forefoot that often causes pain and functional limitations. Assessing all deformity components, such as the distal metatarsal articular angle (DMAA) is essential to hallux valgus treatment. Nevertheless, interobserver agreement of DMAA is poor on plain radiographs. The present study compared computed tomographic (CT) 3-dimensional (3D) reconstruction with plain radiographic measurements for measuring the DMAA. We included 43 consecutive patients (77 feet), diagnosed with hallux valgus at the orthopedic outpatient clinic at Hospital de Clínicas de Porto Alegre (Porto Alegre, Brazil) from April 2014 to June 2015 in our prospective study. The DMAAs were measured by 2 observers using CT 3D reconstruction. The results were compared between observers and with the plain radiographic measurements using the concordance correlation coefficient and the Bland-Altman plot to determine the agreement between the 2 methods. The interobserver agreement of the CT 3D measurements was high (concordance correlation coefficient 0.90; p < .001). Significant agreement was found between the plain radiographic and CT measurements (concordance correlation coefficient 0.667; p < .001). The Bland-Altman plot showed that the difference between the plain radiographic and CT measurements increased when greater DMAA values were associated with the presence of metatarsal rotation. The interobserver agreement of DMAA measurements was greater on CT 3D reconstruction than on plain radiography. The poor interobserver agreement of the radiographic DMAA might have resulted from metatarsal rotation.
authors.affiliation: Medical Assistant, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil; Orthopaedist and Traumatologist, Foot and Ankle Surgery Specialty, Foot and Ankle Orthopaedic Surgeon, Department of Orthopaedics, Santa Casa de Misericórdia Hospital, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Eduardo Pedrini
authors.initials: EP
authors.lastname: Cruz
authors.affiliation: Medical Assistant, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil; Radiologist, Musculoskeletal Disorders Specialty, Musculoskeletal Radiologist Staff, Hospital Moinhos de Vento, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Felipe Victora
authors.initials: FV
authors.lastname: Wagner
authors.affiliation: Medical Assistant, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil; Orthopaedist and Traumatologist, Foot and Ankle Surgery Specialty, Foot and Ankle Orthopaedic Surgeon, Hospital de Clınicas de Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Carlo
authors.initials: C
authors.lastname: Henning
authors.affiliation: Orthopaedist and Traumatologist, Foot and Ankle Surgery Specialty, Foot and Ankle Orthopaedic Surgeon, Department of Orthopaedics, Mãe de Deus Hospital, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: José Antônio Veiga
authors.initials: JAV
authors.lastname: Sanhudo
authors.affiliation: Biomedical Scientist, Biomedical, Hospital de Clınicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil; Staff Member, Tissue Bank, Hospital de Clınicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil; Staff Member, Research Group in Hip, Biomaterials and Tissue Bank, Hospital de Clınicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Fernando
authors.initials: F
authors.lastname: Pagnussato
authors.affiliation: Adjunct Professor, Medicine School of Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil; Titular Professor, Post-Graduate Program of Surgical Sciences, Medicine School of Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil; Hip Orthopaedic Surgeon, Department of Orthopaedics, Hospital de Clınicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil; Chief, Tissue Bank, Hospital de Clınicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil; Leader, Research Group in Hip, Biomaterials and Tissue Bank, Hospital de Clınicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil. Electronic address: cgalia@hcpa.edu.br.
authors.forename: Carlos Roberto
authors.initials: CR
authors.lastname: Galia
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006215:Hallux Valgus / Q000000981:diagnostic imaging*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008682:Metatarsal Bones / Q000000981:diagnostic imaging; D008683:Metatarsophalangeal Joint / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D008875:Middle Aged; D015588:Observer Variation; D011859:Radiography; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: distal metatarsal articular angle; hallux valgus; tomography; x-ray image