Modified anteroposterior and oblique radiographs of the midfoot and their efficiency in demonstrating the tarsometatarsal joints

Abstract

To assess whether conventional and modified anteroposterior and oblique radiographs of the midfoot can be used to demonstrate tarsometatarsal (TMT) joints clearly. Conventional anteroposterior and oblique radiographs of the midfoot were taken of 152 volunteers. Modified radiographs of the midfoot were taken of 14 volunteers by tilting the radiographic system tube and placing volunteers' feet on different footboards. Both conventional and modified radiographs were taken of 27 patients with midfoot injuries to demonstrate the injuries to the TMT joints. Two radiologists assessed the radiological demonstration of the TMT joints. Statistical analyses were performed using SPSS 13.0 for Windows. Conventional radiographs of the midfoot did not sufficiently clearly demonstrate TMT joints. They could not demonstrate the majority of the TMT joints. The modified anteroposterior radiographs of the midfoot taken with the radiographic system tube tilted 30° towards the calcaneus demonstrated most TMT joints clearly. The modified oblique radiographs taken with the foot placed on a 30° footboard and with the radiographic system tube tilted 20° towards the calcaneus also showed the majority of TMT joints clearly. For the evaluation of midfoot injuries, modified radiographs perform better than conventional radiographs. Modified anteroposterior and oblique radiographs, which allow clear detection of the articulation and trabeculae of TMT joints, are valuable alternatives when assessing TMT joints.