Reported complications after spinopelvic fixation for U-type sacral fractures in older adults: a systematic review with narrative synthesis.

BACKGROUND

Spinopelvic fixation (SPF), alone or combined with iliosacral or transiliac-transsacral fixation, is often used for highly unstable posterior pelvic ring injuries and some fragility fracture patterns in older adults. However, the evidence specifically describing complications after SPF in older patients with U-type sacral fractures is limited.

METHODS

This systematic review was conducted according to the Cochrane Handbook and PRISMA recommendations. PubMed, Embase, and grey-literature sources were searched from January 1, 2000 to July 31, 2025. Eligible studies included adults aged 60 years or older with U-type sacral fractures or closely related spinopelvic dissociation/FFP IVb patterns treated with SPF, and reporting at least one complication. Because of the small number of eligible studies, probable cohort overlap, heterogeneity in fracture definitions, treatment indications, fixation constructs, and outcome reporting, findings were synthesized narratively rather than pooled quantitatively.

RESULTS

Three studies met the eligibility criteria, comprising 157 patients overall; however, only a subset underwent SPF, and two studies were produced by the same group with probable cohort overlap. The available cohorts mixed bilateral sacral fragility fractures, FFP IVb patterns, and comparative SPF-versus-trans-sacral constructs. Reported adverse events included wound or infectious complications, urinary tract infection and other medical complications, reoperation, and mortality. Construct-specific complication rates for true SPF-treated U-type fractures in older adults could not be estimated reliably.

CONCLUSION

The available literature on SPF for U-type sacral fractures in older adults is extremely limited, clinically heterogeneous, and partly overlapping. Current evidence permits only a cautious narrative description of reported complications; it does not allow reliable estimation of complication rates, meaningful comparison with alternative fixation strategies, or definitive conclusions regarding indications for routine SPF use in this population.