Fig. 4From: A case-driven hypothesis for multi-stage crack growth mechanism in fourth-generation ceramic head fracturea Impingement between the acetabular cup and the neck with the intact ceramic head. The lateral side of the neck impinges on the metal shell (white arrow). b Impingement between the acetabular cup and the neck without the ceramic head. The lateral side of the neck impinges on the ceramic liner (white arrow)Back to article page