Preoperative frontal weight-bearing hip radiographs were retrieved to analyze the femoral morphology according to the Dorr classification,29 (link) as well as several anatomical parameters including the frontal canal bone ratio (CBR),30 (link) CFI,31 and CCR (Figure 2 ).32 Preoperative lateral weight-bearing hip radiographs were also used to measure the lateral CBR. The intramedullary canal width was measured at four levels relative to the lesser trochanter (LT): P1, 2 cm above the tip of the LT; P2, at the level of the tip of the LT; P3, 2 cm below the tip of the LT; and D1, 7 cm below the tip of the LT.19 (link)Immediate postoperative frontal weight-bearing hip radiographs were acquired to assess femoral component width at the four different levels (P1, P2, P3, and D1) and to calculate the CFR at each level, by dividing the width of the femoral component by the width of the intramedullary bone canal.
Postoperative frontal weight-bearing hip radiographs were assessed at a minimum follow-up of two years for 138 hips (128 patients), to evaluate the femoral component osseointegration using the Engh score (worst = −27.5, best = +22.0), which comprises fixation and stability categories.33 Adequate femoral component fixation is characterized by the absence of radiolucent lines around its intramedullary surface and the presence of spot welds, while adequate femoral component stability is defined by the absence of pedestals below the tip of the femoral component, calcar atrophy, radiolucent lines, femoral component migration < 5 mm, and particle shedding. The question in the Engh questionnaire regarding radiolucent lines in non-HA-coated zones was left blank (unanswered) as the femoral component studied is HA-coated over its entire intramedullary surface. The authors also evaluated postoperative femoral component alignment within the femoral canal, which was arbitrarily defined as neutral if within ± 5°.
All radiological analyses and interpretations were performed by a single junior surgeon (AD) using a digital DICOM viewer (Centricity; General Electric, Boston, Massachusetts, USA).
Postoperative frontal weight-bearing hip radiographs were assessed at a minimum follow-up of two years for 138 hips (128 patients), to evaluate the femoral component osseointegration using the Engh score (worst = −27.5, best = +22.0), which comprises fixation and stability categories.33 Adequate femoral component fixation is characterized by the absence of radiolucent lines around its intramedullary surface and the presence of spot welds, while adequate femoral component stability is defined by the absence of pedestals below the tip of the femoral component, calcar atrophy, radiolucent lines, femoral component migration < 5 mm, and particle shedding. The question in the Engh questionnaire regarding radiolucent lines in non-HA-coated zones was left blank (unanswered) as the femoral component studied is HA-coated over its entire intramedullary surface. The authors also evaluated postoperative femoral component alignment within the femoral canal, which was arbitrarily defined as neutral if within ± 5°.
All radiological analyses and interpretations were performed by a single junior surgeon (AD) using a digital DICOM viewer (Centricity; General Electric, Boston, Massachusetts, USA).