Pelvic ramus fractures in the elderly: 50 patients studied with MRI.

Background: Whilst it is well known that fractures of the pelvic rami in the elderly are frequently associated with posterior ring injuries, the extent of this second injury is less well known. We evaluated this question by MRI scanning a group of elderly patients presenting at our unit with pelvic rami fractures.

Patients And Methods: We investigated 50 consecutive elderly patients (45 women) with fractures of the pelvic rami using an MRI scan of the pelvis in order to assess the competency of the pelvic ring.

Results: On MRI, 45 (95% CI 42-48) patients had a sacral fracture. At 5-month follow-up, 39 (of 41 reviewed) still complained of posterior sacral tenderness.

Interpretation: Pelvic rami fractures in the elderly are nearly always associated with posterior ring injuries. This probably explains why these patients take longer to rehabilitate than might be expected if only the anterior injury is considered, and it also explains why they experience long-term back pain.