Normal osseous variants presenting as cystic or lucent areas on radiography and CT imaging: a pictorial overview.

We present a number of commonly encountered pseudolesions. These represent areas of the skeleton that are relatively radiolucent simulating an osteolytic or cystic lesion. Such areas discussed in this article include the superolateral humeral head, rhomboid fossa of the clavicle, scapular defect, supratrochlear foramen, biceps tendon insertion, vascular channel of the ulna, distal condylar area of the knee, 'bone in bone' disturbance, dorsal defect of the patella, metadiaphyseal area, 'Wards' triangle', inframalleolar fossa of the fibula, and anterior lytic defect of the calcaneus. We provide an overview of commonly encountered pseudolesions, that may lead to false positive diagnosis of an osteolytic or cystic lesion.