Radiological Inclination (RI) is defined as the angle formed between the acetabular axis and the longitudinal axis when projected onto the coronal plane. Higher RI angles are associated with adverse outcomes. Primary aim: to investigate the effect of adjusting patient pelvic position in the transverse plane by using a ‘head-down’ (HD) operating table position. This was to determine, when aiming for 35° Apparent Operative Inclination (AOI), which operating table position most accurately achieved a target post-operative RI of 42°. N=270. Patients were randomised to one of three possible operating table positions: 0°HD (Horizontal), 7°HD, or Y°HD (Patient Specific Table Position) Operating table position was controlled using a digital inclinometer. RI was measured using EBRA software.Introduction
Methods
Operative inclination (OI) is defined as the angle between the acetabular axis and the sagittal plane. With the patient in the true lateral decubitus position, this corresponds to the angle formed between the handle of the acetabular component inserter and the theatre floor intra-operatively. The primary study aim was to determine which method of acetabular component insertion most accurately allows the surgeon to obtain a target OI of 35o. 270 consecutive patients undergoing cementless THA were randomised to one of three possible methods for acetabular component implantation: 1. Freehand, 2. 35o mechanical alignment guide (MAG), or 3. Digital inclinometer assisted Two surgeons participated. Target OI was 35o in all cases. OI was measured using a digital inclinometer. For the freehand and MAG cases, the surgeon was blinded to inclinometer readings intra-operatively.Introduction
Patients/Materials & Methods