Robotic-assisted Total Hip Arthroplasty and Spinopelvic Parameters: A Review

Abstract

Total hip arthroplasty (THA) is an effective treatment for osteoarthritis, and the popularity of the direct anterior approach has increased due to more rapid recovery and increased stability. Instability, commonly caused by component malposition, remains a significant concern. The dynamic relationship between the pelvis and lumbar spine, deemed spinopelvic motion, is considered an important factor in stability. Various parameters are used in evaluating spinopelvic motion. Understanding spinopelvic motion is critical, and executing a precise plan for positioning the implant can be difficult with manual instrumentation. Robotic and/or navigation systems have been developed in the effort to enhance THA outcomes and for implementing spinopelvic parameters. These systems can be classified into three categories: X-ray/fluoroscopy-based, imageless, and computed tomography (CT)-based. Each system has advantages and limitations. When using CT-based systems, preoperative CT scans are used to assist with preoperative planning and intraoperative execution, providing feedback on implant position and restoration of hip biomechanics within a functional safe zone developed according to each patient's specific spinopelvic parameters. Several studies have demonstrated the accuracy and reproducibility of robotic systems with regard to implant positioning and leg length discrepancy. Some studies have reported better radiographic and clinical outcomes with use of robotic-assisted THA. However, clinical outcomes comparable to those for manual THA have also been reported. Robotic systems offer advantages in terms of accuracy, precision, and potentially reduced rates of dislocation. Additional research, including conduct of randomized controlled trials, will be required in order to evaluate the long-term outcomes and cost-effectiveness of robotic-assisted THA.

Keywords: Osteoarthritis; Robotic-assisted surgery; Spinopelvic parameters; Total hip arthroplasty.

Fig. 1

Patient positioned for standing lateral radiograph (A) and sitting lateral radiograph (B).

Fig. 2

(A) Spinopelvic parameters on standing illustration. (B) Standing radiograph. (C) Spinopelvic parameters on sitting illustration. (D) Sitting radiograph. SS: sacral slope, PT: pelvic tilt, PI: pelvic incidence, APP: anterior pelvic plane, LL: lumbar lordosis angle, PFA: pelvic-femoral angle.

Fig. 3

Preoperative planning with spinopelvic parameters. Red indicates bone-bone or implant impingement. SS: sacral slope, PT: pelvic tilt.

Fig. 4

Preoperative planning with post-operative radiograph. (A) Preoperative X-ray in a 17-year-old male with DiGeorge Syndrome. (B) Acetabular implant plan with planned impaction grafting of protrusio defect. (C) Femoral implant plan. (D) Virtual range of motion with impingement at 115° flexion and 20° internal rotation. (E) Virtual anteroposterior (AP) pelvis X-ray. (F) Clinical 6-week postoperative AP pelvis X-ray.

Fig. 5

Intraoperative set up for posterior total hip arthroplasty (THA) with patient in the lateral decubitus position (A) and anterior THA in the supine position (B).