Consideration of pelvic tilt at the time of preoperative planning improves standing acetabular position after robotic-arm assisted total hip arthroplasty

Abstract

Introduction:

Approximately half of dislocating total hip arthroplasties (THAs) demonstrate acetabular component position within traditional safe zones. It is unclear if postoperative functional acetabular position can be reliably improved by considering preoperative pelvic tilt. We investigated whether standing cup position targets could be more accurately achieved by considering preoperative standing pelvic tilt in addition to bone landmarks when planning for robot-assisted THA.

Methods:

We reviewed 146 THAs performed by a single surgeon using computed tomography-based 3-dimensional planning and robotic technology to guide acetabular reaming and component insertion. Planning for 73 consecutive cases started at 40° of inclination and 22° of anteversion relative to the supine functional plane and was adjusted to better match native hip anatomy. Planning for the next 73 cases was modified to consider standing pelvic position based on standing preoperative radiographs. We compared groups to determine the rate when cups were placed outside our standing targets of 15–30° anteversion and 35–50° inclination.

Results:

Cup position proved to be reliable in both groups, with 83% of cups in the anatomic planning cohort and 90% of cups in the functional planning cohort achieving standing targets for both anteversion and inclination (p = 0.227). Variances were lower in the functional planning group: 9.4° versus 15.8° of inclination (p = 0.079) and 18.3° versus 26.1° of anteversion (p = 0.352). The range of functional positions was narrower in the functional planning group: 35.7–47.5° versus 31.8–54.9° of inclination and 16.7–35.0° versus 10.1–35.9° of anteversion.

Discussion:

Our results suggest enhanced planning that considers pelvic tilt, when coupled to a precision tool to achieve the plan, can reliably achieve target standing component positions. Considering preoperative functional pelvic position may improve postoperative functional acetabular component placement in THA, but the clinical benefit of this has yet to be confirmed.

Keywords

acetabular cup robotic-assistance total hip arthroplasty

Get full access to this article

View all access options for this article.

References

Banerjee

Cherian

Elmallah

, et al. Robot-assisted total hip arthroplasty. Expert Rev Med Devices 2016; 13: 47–56.

Elmallah

Cherian

Jauregui

, et al. Robotic-arm assisted surgery in total hip arthroplasty. Surg Technol Int 2015; 26: 283–288.

Perets

Mont

, et al. Current topics in robotic-assisted total hip arthroplasty: a review. Hip Int 2020; 30: 118–124.

Callanan

Jarrett

Bragdon

, et al. The John Charnley Award: risk factors for cup malpositioning: quality improvement through a joint registry at a tertiary hospital. Clin Orthop Relat Res 2011; 469: 319–329.

Danoff

Bobman

Cunn

, et al. Redefining the acetabular component safe zone for posterior approach total hip arthroplasty. J Arthroplasty 2016; 31: 506–511.

Lewinnek

Lewis

Tarr

, et al. Dislocations after total hip-replacement arthroplasties. J Bone Joint Surg Am 1978; 60: 217–220.

Abdel

von Roth

Jennings

, et al. What safe zone? The vast majority of dislocated thas are within the Lewinnek safe zone for acetabular component position. Clin Orthop Relat Res 2016; 474: 386–391.

DelSole

Vigdorchik

Schwarzkopf

, et al. Total hip arthroplasty in the spinal deformity population: does degree of sagittal deformity affect rates of safe zone placement, instability, or revision? J Arthroplasty 2017; 32: 1910–1917.

Esposito

Gladnick

Lee

, et al. Cup position alone does not predict risk of dislocation after hip arthroplasty. J Arthroplasty 2015; 30: 109–113.

10.

Jauregui

Banerjee

Elmallah

, et al. Radiographic evaluation of hip dislocations necessitating revision total hip arthroplasty. Orthopedics 2016; 39: e1011–1018.

11.

McLawhorn

Sculco

Weeks

, et al. Targeting a new safe zone: a step in the development of patient-specific component positioning for total hip arthroplasty. Am J Orthop (Belle Mead NJ) 2015; 44: 270–276.

12.

Timperley

Biau

Chew

, et al. Dislocation after total hip replacement - there is no such thing as a safe zone for socket placement with the posterior approach. Hip Int 2016; 26: 121–127.

13.

Esposito

Carroll

Sculco

, et al. Total hip arthroplasty patients with fixed spinopelvic alignment are at higher risk of hip dislocation. J Arthroplasty 2018; 33: 1449–1454.

14.

Kanawade

Dorr

Wan

Predictability of acetabular component angular change with postural shift from standing to sitting position. J Bone Joint Surg Am 2014; 96: 978–986.

15.

Redmond

Gupta

Hammarstedt

, et al. Accuracy of component placement in robotic-assisted total hip arthroplasty. Orthopedics 2016; 39: 193–199.

16.

Kamara

Robinson

Bas

, et al. Adoption of robotic vs fluoroscopic guidance in total hip arthroplasty: is acetabular positioning improved in the learning curve? J Arthroplasty 2017; 32: 125–130.

17.

Redmond

Gupta

Hammarstedt

, et al. The learning curve associated with robotic-assisted total hip arthroplasty. J Arthroplasty 2015; 30: 50–54.

18.

Ferber

Kendall

McElroy

Normative and critical criteria for iliotibial band and iliopsoas muscle flexibility. J Athl Train 2010; 45: 344–348.

19.

Widmer

Reising

Kotter

, et al. Correct assessment of acetabular component orientation in total hip arthroplasty from plane radiographs. J Arthroplasty 2018; 33: 2652–2659.e3.