Intra- and Intersurgeon Variability in Image-free Navigation System for THA

Abstract

In image-free navigation systems, cup orientation is determined in the pelvic coordinate by registration of bony landmarks. While the value of navigation relates primarily to the reliability and accuracy of cup placement, the reliability of registration plays a role in cup placement. We therefore examined intra- and intersurgeon variability in registration and the distance between registration points in each bony landmark. Thirty-seven THAs were performed in the lateral position and 15 THAs in the supine position. The cup was fixed using a navigation system. The registration was repeated two more times by operator and assistant, and the intra- and intersurgeon variability of cup abduction angle and anteversion was analyzed by ICC (intraclass correlation coefficients). In 25 hips, the distance between intrasurgeon registration points and between intersurgeon registration points in each landmark were calculated. The ICC in the lateral position ranged between 0.59 and 0.81, and between 0.85 and 0.95 in the supine position. The ICCs of cup abduction angle for the intra- and intersurgeon variability were 0.92 and 0.95 for the supine position and 0.65 and 0.59 for the lateral position. Those of anteversion were 0.93, 0.85, and 0.81, 0.72, respectively. The variability in locating the ASIS in the lateral position was greater than that in the supine position. The variability of registration points depended on bony landmarks and patient position but the range of variability we found would not likely result in a large variability in cup placement.

A review of computer‐assisted orthopaedic surgery systems

“…We reviewed the clinical use of hip surgery navigation systems from 2008 to the present, for a total of 13 navigation systems, including commercial navigation systems and navigation systems independently developed by medical institutions, of which there were seven image‐free navigation systems. Stryker Navigation (Stryker Corp, Kalamazoo, Michigan) 12,141‐146 appeared seven times, Orthopilot Navigation System (B/Braun‐Aesculap, Melsungen, Germany) 7,147‐150 appeared five times, Vector Vision hip CT‐based ver. 3.5.2 (BrainLab, Heimstetten, Germany) 14,151‐153 appeared four times, Navitrack imageless computer navigation system (ORTHOsoft, Montreal, Canada) 154‐156 appeared three times, BrainLab hip 6.0 (BrainLab, Heimstetten, Germany) 157,158 appeared twice, and the N‐navi (TEIJIN NAKASHIMA MEDICAL, Okayama, Japan), 159 BrainLab hip 2.1‐5.1 (BrainLab, Heimstetten, Germany), 160 MAKO robot arm navigation (Stryker Corp, Kalamazoo, Michigan), 161 Ci System (Orthopaedics, Inc, Warsaw, Indiana, and BrainLAB AG, Feldkirchen, Germany), 13 Orthosoft Hip 2.2 Universal Surgical Technique (Zimmer, Warsaw, Indiana), 162 AchieveCAS (Smith & Nephew, Inc), 163 VVHIP3.5 (BrainLAB, Feldkirchen, Germany), 164 and Hip unlimited 5.0 (BrainLab, Heimstetten, Germany) 165 each appeared once.…”

Recent Trends, Technical Concepts and Components of Computer-Assisted Orthopedic Surgery Systems: A Comprehensive Review

“…Instead of that, a DRF is directly attached to the pelvis, and consequently the pelvis coordinates are generated intraoperatively by using the anatomic landmarks. Some studies proved better accuracy of this technique for the cup alignment than conventionally used mechanical instruments [163,164,165,166]. In the case of the fluoroscopic navigation, it is used the same technique for placing the anatomic landmarks as in the imageless navigation.…”

Computer-Assisted Orthopaedic Surgery and Robotic Surgery in Total Hip Arthroplasty

“…Several clinical studies demonstrated better cup alignment with the use of imageless navigation than the conventional mechanical instruments 35-40). However, accuracy depends on the technique of landmark pointing and soft tissue thickness on the landmarks 41-44). Moreover, the individual's sagittal tilt is not taken into account when APP is used for the pelvic coordinates 43).…”