Patent ID: 6979341

Claim:
A device comprising a wall made from a flexible material resistant to abrasion by cancellous bone, the wall peripherally defining an interior space and including an expandable region preformed with a normally expanded shape outside bone, the expandable region being expandable beyond its normally expanded shape to reach an inflation volume sized and configured for compacting cancellous bone, the expandable region having proximal and distal ends, the expandable region further having a first expanded section having an interior cross-sectional area adjacent the proximal end, a second expanded section having an interior cross-sectional area adjacent the distal end, and a third section having an interior cross-sectional area located between the first and second expanded sections, when in the normally expanded shape and at the inflation volume, the interior cross-sectional area of the third section being less than the interior cross-sectional area of either the first or second expanded sections, and the first expanded section, the second expanded section, and the third expanded section further having, respectively, a first preformed average wall thickness, a second preformed average wall thickness, and a third preformed average wall thickness, and when in the normally expanded shape and at the inflation volume, the third average wall thickness being greater than either the first average wall thickness or the second average wall thickness.