An Update to a Novel Technique for Centering the Femoral Stem in Primary Total Hip Arthroplasty

Careful surgical technique is a critical component of total hip arthroplasty. Femoral preparation and component positioning are vital to improving outcomes and preventing complications. Femoral preparation begins with creating an entry hole in the proximal femur. Various tools have been used for this purpose which resemble a "cookie cutter." An axial starter reamer, or awl, is then inserted through the entry hole in the proximal femur to aid in opening and centralizing the canal for sequential reaming or broaching. A novel technique was described previously which allows the awl to center itself in the canal with little risk of deviation from midline or cortical perforation. Since describing this technique in 2014, the senior surgeon has further modified the method of preparing the entry hole in the proximal femur. The surgeon now uses a 1/8" drill bit to penetrate the piriformis fossa, instead of a "cookie cutter" or osteotome. A 1/8" entry hole eliminates gaps between the bone and the implant, results in lateralization of the stem, and avoids varus malposition. We evaluated 300 primary hip arthroplasties by a single surgeon using one of the three techniques: traditional clockwise technique (Group 1), our previously published novel counterclockwise technique (Group 2), and our updated novel technique (Group 3). While the deviation from midline of Group 3 did not differ significantly from Group 2, it was significantly less than the deviation from midline of Group 1 (p=00006). This simple updated technique enables the surgeon to avoid potential malalignment during femoral preparation.