Periprosthetic acetabular fractures.

Periprosthetic acetabular fractures are a major challenge in orthopedics. Proper recognition of these complex cases helps to identify and treat patients with different presentations. These fractures can occur intraoperatively and be treated immediately, or they can occur postoperatively, following trauma or in the context of chronic low bone quality or associated implant loosening. The existing classification systems categorize these fractures as a function of the acetabular cup's stability and the context surrounding the fracture. When a fracture is detected intraoperatively, immediately analyzing its stability is crucial for choosing between a conservative strategy, the need for additional fixation, or the need to change the cup or use of an acetabular reinforcement ring. When the patient has symptoms such as persistent pain or instability, secondary diagnosis of a fracture requires diagnostic imaging. Its treatment depends on the cup's stability, with options ranging from conservative treatment with functional limitations, cup revision potentially combined with stabilization of the fracture site, and also management of potential periprosthetic bone defects. Traumatic fractures require a comprehensive assessment to determine whether the acetabular cup is still stable. The treatment may be conservative or surgical (internal fixation or cup revision). Chronic pelvic discontinuity is associated with bone loss and implant loosening. Acute pelvic discontinuity requires treatment tailored to each patient, often with acetabular rings or custom triflange cups to restore function. This article aims to provide an in-depth review of periprosthetic acetabular fractures, touching on their causes, classification, assessment and treatment, along with specific considerations for fractures diagnosed postoperatively and following acute trauma. LEVEL OF EVIDENCE: IV; systematic review of level II-IV studies.