Scintigraphic assessment of the acetabulum after arthroplasty with reference to cup geometry.

A unique scintigraphic appearance has been noted in uncomplicated hip prostheses which have the acetabular component inserted after under-reaming or where a cone-shaped cup is inserted. We hypothesized that the pattern of increased uptake around the superior and inferior third of the cup with relatively reduced uptake in the medial third is due to preferential loading of the rim of the cup. A prospective study of ten patients with uncomplicated hip prostheses supports the hypothesis.