Zimmer Biomet Persona Manual

Also see for Persona: SURGICAL TECHNIQUE

Zimmer Biomet Persona Manual Manual pdf 21 page image

19 | Persona The Personalized Knee Surgical TechniquePersona Anterior Referencing Sizer42-5099-088-102.5 mm Male Hex Driver42-5099-025-0025 mm x 2.5 mm Female Hex Screw42-5099-025-25Size Femur andEstablish External RotationRotate the feet of the anterior referencing femoralsizing guide so the appropriate “Left” or “Right”markings are visible as the femoral sizing guide isplaced on the bone (Figure 36). External rotation canbe set at 3 degrees or 5 degrees from the posteriorcondylar axis.Technique Tip: Remove any osteophytes thatinterfere with instrument positioning.Apply the sizer so that the flat surface of the sizer isflush against the resected surface of the distal femurand the feet of the sizer are flush against the posteriorcondyles. Center the sizer mediolaterally. Both thevertical and horizontal portions of the sizer providevisual cues relative to the A/P and epicondylar axes ofthe femur to help ensure that desired external rotationis attained.Note: Sizer geometry is rotated 3 degrees to alignto the A/P and epicondylar axes of the femur. The3 degrees drill holes are rotated 3 degrees fromthe posterior feet and are neutral to the centralsizer geometry. This enables use of the A/P andepicondylar axis to set rotation.SideDesignationFigure 36Figure 37Figure 38If the 3 degrees external rotation holes are to be usedto set external rotation, the etched line on the sizershould be positioned so it is in line with Whiteside’s line(Figure 37) to optimize the M/L position of the drillholes for subsequent 4-in-1 cut guide placement. Ifthe 5 degrees external rotation holes are to be used,the sizer can be positioned with the etched line onthe sizer 4 mm laterally from Whiteside’s line to bettercenter the drill holes for subsequent 4-in-1 cut guideplacement, due to the M/L offset of the holes. Holdthe guide in place and if necessary, secure the sizerto the femur using 25 mm x 3.2 mm (2.5 mm femalehex) screws (Figure 38) in one or both of the holeson the lower portion of the guide to help draw thesizer adjacent to the distal femur, particularly in MISsituations.Note: Do NOT use 48 mm screws for fixation ofthe anterior reference sizer. 48 mm screws are notrecommended due to potential bone perforation.Technique Tip: Do not impact the sizer onto thefemur.