Unravelling the secrets of foetal wound healing: an insight into fracture repair in the mouse foetus and perspectives for clinical application

This study was designed to investigate the nature of mammalian foetal fract ure healing in utero. A compound 'pinch' fracture was created in the foetal mouse ulna at the end of the second trimester, prior to mineralisation, an d healing observed in whole mount limbs and in histological section. Cartil aginous ends gained initial contact within a perichondrial sleeve by 24 h. Bony union was achieved within 48 h by cartilage remodelling during the pha se of primary endochondral ossification in the limb, a process to which adu lt fracture healing aspires. The molecular response to wounding was investi gated using a whole mount in situ hybridisation technique and antisense mRN A probes to three target genes (BMP-2, BMP-4 and GDF-5). These experiments failed to identify altered expression ill wounded limbs compared with contr ols. (C) 2000 The British Association of Plastic Surgeons.