Minimally Invasive Technique for PMMA Augmentation of Fenestrated Screws

Figure 3

Exemplary assembly of injection cannula and polyaxial cannulated and fenestrated screw for percutaneous cement augmentation. The injection cannula is initially inserted unfilled into the polyaxial screw head (a) to check the proper fit and entry trajectory (b). After removing and filling the injection cannula with bone cement outside of the patient’s body, the filled injection cannula is reinserted (c). Gradually inserting the pusher into the injection cannula (under fluoroscopic monitoring) bone cement is injected into the screw and surrounding vertebral body through the distal fenestrations (d) (bone cement not shown).

(a)

(b)

(c)

(d)