SYSTEMS AND METHODS FOR FORMING A CAVITY IN CANCELLOUS BONE
A cavity creating device having a cavity creating axis is introduced through a percutaneous access path into a cancellous bone volume, e.g., within a vertebral body. The cavity creating device is manipulated to form a cavity in the cancellous bone volume. The manipulation includes deflecting the cavity creating device along the cavity creating axis relative to the axis of the access path. A material, such as bone cement, can be conveyed into the cavity.
1 - 14 . (canceled)
15 . An instrument for forming a cavity in cancellous bone comprising:
a generally straight catheter tube having a proximal end, a distal end, a first lumen and a second lumen;
an expandable structure disposed at the distal end of the catheter tube, the expandable structure having a distal end and communicating with the first lumen of the catheter tube; and
a generally straight stiffening stylet inserted into the second lumen of the catheter tube;
wherein the second lumen extends through the first lumen of the catheter tube to the distal end of the expandable structure.
16 . The instrument according to claim 1 , wherein the expandable structure is made from an elastic material.
17 . The instrument according to claim 1 , wherein the stylet is removable from the second lumen.
18 . The instrument according to claim 1 , wherein the stylet is formed from metal.
19 . The instrument according to claim 1 , wherein the stylet is formed from plastic.
20 . An instrument for forming a cavity in cancellous bone comprising:
a generally straight outer catheter tube including a distal end and a first lumen;
a generally straight inner catheter tube extending within the outer catheter tube and including a distal end and a second lumen, wherein the distal end of the inner catheter tube extends beyond the distal end of the outer catheter tube;
an expandable structure communicating with the first lumen; and
a generally straight stiffening stylet sized for insertion into the second lumen.
21 . The instrument of claim 20 wherein the expandable structure includes a proximal end and distal end and wherein the distal end of the expandable structure is attached to the distal end of the inner catheter tube.
22 . The instrument of claim 20 wherein the stylet is formed of metal.
23 . The instrument of claim 20 wherein the stylet is formed of plastic.
24 . The instrument of claim 20 wherein the stylet includes a region with a preformed memory.
25 . The instrument of claim 20 further comprising a guide sheath sized for through passage of the stylet and catheter tubes.
26 . The instrument of claim 20 wherein the inner catheter tube is formed from a material more compliant than the material from which the outer catheter tube is formed.