LAUSR

To investigate the value of modified calcaneal axial radiograph—the horizontal calcaneal axial radiograph in diagnosing calcaneal fractures, patients who had acute calcaneal fractures or internal fixation were enrolled, and three groups were established, including the acute fracture group (n = 20), the internal fixation group (n = 20), and the healthy control group (n = 20). All the subjects had regular and modified calcaneal axial radiograph for comparison. In analysis of the results, all volunteers could have ankle dorsiflexion at different degrees. When the ankle was at 30º dorsiflexion for regular axial radiograph, the subtalar joint and the sustentaculum tali could not be clearly displayed. The calcaneus was elongated if the tube tilted in a larger angle but shortened if the tube titled in a smaller angle. When the ankle was at neutral (0º dorsiflexion) location with the tube tilting 45° cephalad or when the ankle was at 20° plantarflexion with the tube tilting 35° cephalad, the subtalar joint, sustentaculum tali, calcaneal body and internal and external calcaneal processes could all be clearly demonstrated. No significant difference (P = 0.79) existed in displaying the bony anatomical structures in regular compared with modified calcaneal axial radiography. For patients with acute calcaneal factures or with internal fixation, the modified calcaneal axial radiography could display more significantly clearly (P = 0.001) bony anatomical structures than the regular one. In conclusion, the modified calcaneal axial radiograph can be performed easily and can clearly show the bony structure of the calcaneus and surrounding bones without adding pain to the patients with calcaneal fractures.