[Acetabulum fractures. Diagnosis, classification, evaluation].

Diagnostics of acetabular lesions rest on careful explored medical history, clinical findings and X-ray-examination. Apart from standard radiography (pelvis a. p., injured hip a. p., iliac-oblique and obturator-oblique), which enables classification and supports strategic therapy decisions, computed tomography is considered indispensable by the majority. Fragment interposition, marginal impaction and concomitant occult pelvic ring fractures are detected and are the basis for special tactical decisions in operative treatment. The classification of Letournel with 5 elementary and 5 associated fracture types is still widely used. The AO-classification gives a solid basis for scientific evaluation and is a fundamental for a therapeutic concept with its basic structure with types and groups, ascending according to damage severity. Evaluation of acetabular fractures has to include additional and concomitant lesions and expected late damages. Only an anatomic reconstruction of the weight bearing part of the socket gives a chance for functional restitution. Osteoarthritis and disabling ectopic ossifications are not always avoidable and are subsequently the cause of impairment and respectively loss of working ability.