We describe a patient with a traumatic spondylolisthesis of L5 and multiple, bilateral pedicle fractures from L2 to L5. Conservative treatment was chosen, with eventual neurological recovery and bony union. We are not aware of previous reports of this pattern of injury.

We studied the precise role of the fracture haematoma in healing by the experimental transplantation of the haematoma at two days and four days after fracture of the rat femur to subperiosteal and intramuscular sites. We used bone marrow and peripheral blood haematomas for control experiments. The transplanted two-day fracture haematoma produced new bone by endochondral ossification at the subperiosteal site, but not at the intramuscular site. Four-day fracture haematoma produced new bone formation at both subperiosteal and intramuscular sites. These results suggest that fracture haematoma has an inherent osteogenetic potential.