Fluoroscopic navigation system for hip surface replacement

Figures & data

Table I.  Computer-assisted hip resurfacing systems currently on the market.

Manufacturer	CT-based	Image-less	Fluoroscopy-based
Brain LAB		VectorVision® hip SR  3D shape model
CAS Innovations	CAPPA® Surface  3D shape model	CAPPA® Surface (near introduction)  3D shape model
Localite		HipNavigator
Medtronic			Hip resurfacing
OrthoSoft (Zimmer)		Navitrack® (near introduction)

Figure 1. (a) Dynamic reference base fixation. (b) Field-of-view registration points.

Figure 2. Image acquisition with the zero-dose C-Arm navigation. (a) Preview of frontal view (acquired image in the background). (b) Preview of lateral view prior to second image acquisition. [Color version available online.]

Figure 3. (a) Safe zone definition. (b) Warning during implant alignment. (c) Final implant position. (d) Offset between planning and result. [Color version available online.]

Figure 4. Left: Virtual representation of the tracked pin trajectory superimposed on an acquired X-ray image. Right: Two different points of the tracked pin trajectory in cross-hair representation. [Color version available online.]

Figure 5. CT evaluation: Implant axis alignment (frontal and lateral view) in relation to femoral neck margins.

Figure 6. Notched probe: Femoral neck notching on the medial portion.