Abstract

Combined acetabular and pelvic ring injuries are not simply “two fractures in one patient.” Reduction and fixation of one component can alter the alignment and reducibility of the other, rendering operative sequencing a primary decision variable rather than a secondary consideration. These injuries typically result from high-energy trauma, frequently occur in patients with polytrauma, and are further influenced by physiological tolerance and the feasibility of available operative corridors. The existing evidence base remains constrained by retrospective study designs, inconsistent definitions, variable classification systems, and heterogeneous outcome reporting, all of which limit the strength of comparative recommendations. This state-of-the-art review presents a surgeon-facing, algorithmic approach grounded in a reference-frame mindset. We emphasize computed tomography (CT)-based mapping and the use of consistent terminology to characterize acetabular morphology, pelvic ring instability, deformity vectors, suspicion of mechanical coupling, and feasible operative corridors. Mechanically connected acetabular and pelvic ring injuries (MCAPI) are introduced as a working framework for identifying patterns in which reduction or fixation of one injury predictably influences the other. In cases of suspected MCAPI, a posterior ring-based sequence is generally preferred, typically consisting of posterior ring reduction and fixation, definitive acetabular reconstruction, and subsequent anterior ring fixation. We propose an explicit intraoperative “go/no-go” checkpoint (reference acceptable, stable, corridors feasible) to prevent acetabular reconstruction on a moving target. Acetabulum-first strategies may be appropriate only in selected anteroposterior compression-type configurations in which acetabular fixation plausibly restores sacroiliac congruency and posterior stabilization remains technically feasible. We summarize key outcome domains and complication patterns, highlighting hip dislocation as an important risk factor associated with both neurologic deficits and overall complications. Standardized CT-based definitions and outcome instruments, together with multicenter cohorts employing predefined decision pathways, are required to test sequencing strategies and to determine whether improved radiographic reduction translates into durable functional benefit.

• Keywords: Acetabulum; Pelvic bones; Bone fractures; Internal fracture fixation; Multiple trauma