TRAUMATIC & POST-PARTUM PELVIC RING INSTABILITY: RECONSTRUCTION & BIOLOGICAL ENHANCEMENT WITH BMP-7

Abstract

The safety and efficacy of bone-healing enhancement with Bone Morphogenetic Protein-7 (BMP) has been studied in the clinical setting of persistent post-traumatic and post-partum pelvic instability. Prospective collection and analysis of all cases with pelvic ring instability after trauma or childbirth, treated with reconstruction and local application of BMP-7. Patient demographics, hospitalisation, operative interventions before and after the BMP-7 grafting, and follow-up data were recorded and evaluated. The median follow-up period was 1 year (range 12 to 18 months).

Over a two-year period (March 2005 – January 2007) nine patients (8 females) with median age of 39 years (31–62) were operated for persistent pelvic instability and pain. The mean number of previous operations was 1,6 procedures. Reconstruction of the pelvic ring included 4 cases of post-partum pubic symphysis instability, 2 traumatic non-unions of pubis symphysis and 3 sacroiliatis (1-septic and 2-aseptic). Reconstruction included double plating of pubis symphysis (4-cases), external pelvic fixation (2-cases), sacroiliac screw fixation (1-case) and anterior sacroiliac plating (2-cases).

In 4 cases BMP-7 was used alone; in 5 it was used together with iliac crest autograft. All patients were mobilizing with a wheelchair for a period of 8 weeks (6–12) before progressing to full weight bearing. Clinical and radiological union occurred in 8/9 cases at a median time of 14 weeks (range 12–20). One female patient with post-partum pubic symphysis instability and a chronic psychiatric disorder is still complaining of pain despite the radiological evidence of progress of fusion. The rest reported resolution of symptoms. No local or systemic complications or adverse events associated with the use of BMP-7 were recorded.

The application of BMP-7 alone or supplementing autografting has been proven to be radiologically 100% and clinically 90% successful and safe following pelvic ring reconstruction as seen in this series of patients.