Abstract
Introduction: Till date, weight-bearing radiographs have been the cornerstone for planning surgeries
on flatfoot. The technique, however, has limitations due to the superimposition of
the bones and the lack of reproducibility. Weight-bearing CT with its unique design
overcomes these limitations and enables cross-sectional imaging of the foot to be
done in the natural weight-bearing position. In this paper, we report our initial
experience in weight-bearing cross-sectional imaging of the foot for assessment of
flatfoot deformity. Materials and Methods: Around 19 known cases of flatfoot were scanned on the weight-bearing CT. Each foot
was then assessed for the various angles and also for the presence/absence of extra-articular
talocalcaneal impingement and subfibular impingement. Other associated abnormalities
like secondary osteoarthritic changes, were also noted. Results: The Meary, as well as the calcaneal angles, were abnormal, in all but one separate
foot. Forefoot abduction was seen in 7 of the 19 feet. The hind foot valgus angle
was greater than 10° in all patients. Extra-articular talocalcaneal impingement was
seen in 13 of 19 feet. Secondary osteoarthritic changes were seen in 14 feet. Conclusion: Weight-bearing CT scan is a very useful technique for evaluation of flatfoot and
associated complications. It overcomes the limitations of the radiographs by providing
multiplanar three-dimensional assessment of the foot in the natural weight-bearing
position and at the same time being easily reproducible and consistent for the measurements
around the foot. The definite advantage over the conventional cross-sectional scanners
is the weight-bearing capability.
Keywords
Extremity CT - flatfoot - pes planus - weight-bearing CT
