title: Radiographic investigation of angular and linear measurements including first metatarsophalangeal joint dorsiflexion and rearfoot to forefoot axis angle.
abstract: This study investigated intra- and inter-rater reliability of several radiographic angular and linear parameters using 6 subjects. Using standard weight-bearing radiographs, the following measurements were performed: first metatarsal protrusion distance, hallux abductus, first intermetatarsal, calcaneal inclination and lateral intermetatarsal angles. Measurement of lateral stressed dorsiflexion of the first metatarsophalangeal joint and the rearfoot-to-forefoot-axis angle taken using a composite view were also obtained. All parameters were measured independently by 2 raters, and measurements were repeated on 3 separate occasions at weekly intervals. Intrarater reliability of radiographic measurements ranged between R = 0.65-1.00 for lateral stressed dorsiflexion, and between R = 0.91 and 0.99 for the rearfoot to forefoot axis angle. Inter-rater reliability of radiographic measurements ranged from R = 0.82-0.99. Specifically, lateral stressed dorsiflexion showed R = 0.87 with a mean difference of -1.47 (confidence interval [CI]: -3.42, 0.47), indicating no significant difference ( t = 1.54, P = 0.13). The rearfoot-to-forefoot-axis angle showed R = 0.92 with a mean difference of -0.15 (CI: -1.05, 0.74), indicating no significant difference ( t = 0.35, P = 0.73). The 7 angular and linear measurements chosen demonstrated high inter- and intrarater reliability. These results indicate that weight-bearing radiographic first metatarsophalangeal joint dorsiflexion using the lateral stressed dorsiflexion view, and measurement of the rearfoot-to-forefoot-axis angle using a composite view could be measured reliably within and between raters.
authors.affiliation: Center for Musculoskeletal Studies, School of Surgery and Pathology, University of Western Australia, Royal Perth Hospital. mtaranto@iprimus.com.au
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Taranto
authors.forename: Julie
authors.initials: J
authors.lastname: Taranto
authors.forename: Alan
authors.initials: A
authors.lastname: Bryant
authors.forename: Kevin P
authors.initials: KP
authors.lastname: Singer
mesh_terms: D000328:Adult; D005260:Female; D005528:Foot / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008683:Metatarsophalangeal Joint / Q000000981:diagnostic imaging* / Q000502:physiology; D008875:Middle Aged; D015588:Observer Variation; D018583:Pliability; D011859:Radiography; D015203:Reproducibility of Results