ABSTRACT
OBJECTIVES/HYPOTHESIS: The objective was to determine the time interval after brow lift required to achieve periosteal readhesion to the skull with preoperative strength [corrected]. STUDY DESIGN: Randomized prospective analysis of variance with repeated measures. METHODS: Twenty-one New Zealand white rabbits, each serving as its own control, underwent subperiosteal elevation on one side of the skull. The elevated periosteum was lifted and fixed to a resorbable screw, and the contralateral periosteum was left untouched. Adhesion characteristics were subsequently examined at postoperative days 5, 6, 7, 8, 10, 12, and 17. Seven subjects were assessed histologically to determine attachment of periosteum to underlying bone. Fourteen subjects underwent biomechanical analysis of the bone-periosteum interface using the following three measures of periosteal readhesion strength: ultimate shear strength, shear stiffness, and shear energy [corrected]. RESULTS: Blinded histological analysis showed a qualitative increase in the number of markers of periosteal healing on days 8 to 12 for the operated sides. Analysis of ultimate shear strength and shear stiffness demonstrated a significant relationship to postoperative day (P <.001). The ultimate shear strength and shear stiffness of the operated side approached that of the nonoperated side by postoperative days 12 and 8, respectively. Shear energy was significantly lower for all time points on the operated side as compared with the control (P <.02). CONCLUSION: Periosteal readhesion after surgical elevation approaches preoperative strength by the twelfth postoperative day.
