INTRODUCTION: Rib fractures may be treated either non-operatively or surgically with internal fixation. The present study describes a reproducible rib fracture model in rabbits to test the hypothesis that a bioresorbable micro-plate fixation system improves healing of fractured ribs.

METHODS: A standard osteotomy was prepared in the 12th rib of 30 skeletally mature New Zealand White rabbits. The rabbits were divided into two treatment groups -- 18 rabbits with fixation devices (Synthes, Inc.) and 12 with non-operative management of the fracture. At designated times (3 and 6 weeks), the ribs were radiographed and processed histologically to assess fracture healing patterns.

RESULTS: At both the 3 and 6-week intervals, 7/9 of the ribs were restored in the animals receiving fixation, while 0/6 and 3/6 of the ribs were restored in the non-operated controls. Restoration was defined as a structural condition similar to the pre-fractured state. Statistical analysis using Fisher’s exact test demonstrated a significant difference between treatment groups at 3 weeks (p=0.007), with significance established at p<0.05. However, by 6 weeks, there was no demonstrable difference between the groups.

CONCLUSION: Fixation of rib fractures with a bioresorbable micro-plate system was superior to the non-operative treatment at the 3-week interval.