Evaluation of the Accuracy of Computed Tomography–Based Navigation for Femoral Stem Orientation and Leg Length Discrepancy

doi:10.1016/j.arth.2010.08.001

The Journal of Arthroplasty

Volume 26, Issue 5, August 2011, Pages 674-679

https://doi.org/10.1016/j.arth.2010.08.001 Get rights and content

Abstract

Although there is a great deal in the literature about the clinical accuracy of computed tomography (CT)–based navigation systems for acetabular cup orientation and leg length discrepancy in total hip arthroplasty, there is little analysis of femoral stem orientation. Thirty total hip arthroplasties in which CT-based navigation system had been used had their anteversion, valgus angle of stem, and leg length discrepancy measured on postoperative CT data. Differences in postoperative measurements from intraoperative records were −0.6° ± 4.8° (range, −11° to 10°) for stem anteversion, −0.2° ± 1.8° (range, −4° to 3°) for valgus angle of stem, and 1.3 ± 4.1 mm (range, −6 to 10 mm) for leg length. Although this system may need further improvement for stem orientation, it was helpful for intraoperative leg length adjustment.

Section snippets

Materials and Methods

From July 2007 to May 2008, 54 THAs with cementless stems (CentPillar, Stryker, Mahwah, NJ) were performed with the use of CT-based navigation system (Stryker CT-Hip System V1.0, Stryker-Leibinger, Freiberg, Germany) in our hospital. All preoperative planning and postoperative measurements were completed on this planning module. As preparation for planning, the CT was taken from pelvis to knee joint and transferred into the planning module. Twenty reference points (bilateral anterior superior

Results

The preoperative planned position of the stem was 34.2° ± 12.4° of anteversion and 0.30°± 2.1° of valgus, and the position of the cup was 20.9° ± 4.5° of anteversion and 41.9° ± 1.1° of inclination. Intraoperative angles were 31.1° ± 11.7°, −0.1° ± 2.6°, 21.4° ± 5.9°, and 40.8° ± 2.0°, respectively. Because 93% of THAs were performed under the diagnosis of secondary osteoarthritis with dysplastic hip in this study, our planned angle (34.2°) was an average angle and not excessive 19, 20.

Discussion

In addition to cup orientation, stem orientation was also taken into consideration as an essential factor in acquiring the optimal range of motion and joint stability in THA. Widmer and Zurfluh [3] suggested that acetabular cups should be oriented between 40° and 45° of radiographic inclination and between 20° and 28° of radiographic cup anteversion, and should be combined with stem anteversion so that the sum of cup anteversion plus 0.7 times the stem anteversion equals 37°. Yoshimine [4]

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Cited by (77)

Comparison of cementless and cemented cups in revision total hip arthroplasty using a computed tomography-based navigation system
2020, Journal of Clinical Orthopaedics and Trauma
Citation Excerpt :
Navigation has been used to improve implantation accuracy and stability of reconstructed hip joints demonstrating the complications mentioned above. While the reported results have generally been favorable, most of these results were from cementless cups.6,9 Many cases of revision THA involve severe bone defects, which are difficult in terms of anatomical orientation and are also technically demanding.
Studies comparing cementless and cemented cups are lacking, especially for revision total hip arthroplasty (THA). The aim of this study was to investigate and compare the differences in implant accuracy between two fixation methods in revision THA.
We conducted a retrospective study of 85 hips in 70 patients who underwent revision THA using a computed tomography (CT)-based navigation system. Among these, 53 hips underwent cementless THA and 32 hips underwent cemented THA. We measured cup inclination and anteversion using the Kyocera two-dimensional-template with X-ray (Japan-Kyocera, Shiga, Japan) and stem anteversion with CT. We calculated the combined anteversion [cup anteversion+0.7×stem anteversion].
There were no significant differences between the two groups with respect to definitive cup inclination and anteversion. The mean deviations in the inclination and anteversion angle were 40.3 ± 4.3 and 19.6 ± 6.2° in the cementless group and 40.5 ± 3.3 and 17.1 ± 5.1° in the cemented group. There were 11 outliers with respect to the Lewinnek safe zone in the cementless group and two in the cemented group (P = 0.072). Although there was no statistically significant difference, the number of safe zone outliers in the cemented group was less than that in the cementless group.
We conclude that when using a navigation system for revision THA, high precision can be obtained for the cup placement angle with or without cement. However, it seems that a major error in the installation angle of the cup is less likely to occur when using a cemented cup than when using a cementless cup in revision THA with a navigation system.
Portable Accelerometer-Based Navigation System for Cup Placement of Total Hip Arthroplasty: A Prospective, Randomized, Controlled Study
2020, Journal of Arthroplasty
Citation Excerpt :
CT-based navigation uses a model of the pelvis extracted from the CT data for preoperative planning and assisting the surgeon intraoperatively. CT-based navigation system is accurate [3,8,9,13,14], but it imposes increasing planning time, cost to the operating team, and radiation to the patients. Imageless navigation does not need preoperative CT scan.
Malposition of the acetabular component during total hip arthroplasty (THA) is associated with increased risk of dislocation, reduced range of motion, and accelerated wear. The purpose of this study is to compare cup positioning with a portable, accelerometer-based hip navigation system and conventional surgical technique.
In a prospective, randomized, clinical study, cups were implanted with a portable, accelerometer-based hip navigation system (navigation group; n = 55) or conventional technique (conventional group; n = 55). THA was conducted in the lateral position and through posterior approach. The cup position was determined postoperatively on pelvic radiograph and computed tomography scans.
An average cup abduction of 39.2° ± 4.6° (range, 27° to 50°) and an average cup anteversion of 14.6° ± 6.1° (range, 1° to 27.5°) were found in the navigation group, and an average cup abduction of 42.9° ± 8.0° (range, 23° to 73°) and an average cup anteversion of 11.6° ± 7.7° (range, −12.1° to 25°) in the conventional group. A smaller variation in the navigation group was indicated for cup abduction (P = .001). The deviations from the target cup position were significantly lower in the navigation group (P = .001, .016). While only 37 of 55 cups in the conventional group were inside the Lewinnek safe zone, 51 of 55 cups in the navigation group were placed inside this safe zone (P = .006). The navigation procedure took a mean of 10 minutes longer than the conventional technique.
Use of the portable, accelerometer-based hip navigation system can improve cup positioning in THA.
Isolated acetabular revision with femoral stem retention using computed tomography-based navigation
2019, Orthopaedics and Traumatology: Surgery and Research
In isolated acetabular revision surgery, surgeons must place the cup at an appropriate angle with various retained stem anteversion angles to prevent postoperative dislocation. For accurate acetabular cup position, various navigation systems have been used. Nevertheless, no publications have reported combined cup and stem anteversion and dislocation rates after isolated acetabular revision, especially comparing the use of navigation with manual implantation. Therefore we performed a retrospective comparative study to answer the following questions: (1) What is the combined anteversion after isolated acetabular revision with computed tomography-based navigation? (2) Does navigation improve the accuracy of cup angle and combined anteversion, (3) reduce dislocation rate, and (4) reduce operative time?
A navigation system makes combined anteversion near the target angle in isolated acetabular revision.
We conducted a retrospective study of 32 hips in 24 patients who underwent isolated acetabular revision total hip arthroplasty using computed tomography-based navigation system. The control group comprised 8 hips in 8 patients who underwent the same procedure without navigation.
In the navigation group, average Widmer's combined anteversion was 39.0° ± 8.7° (range, 25.3°–56.6°). Cup positions were 40.3° ± 2.9° (range, 29.0°–49.0°) for radiographic abduction angle, 24.3° ± 8.0° (range, 4.6°–42.6°) for radiographic anteversion. In the control group, Widmer's combined anteversion was 47.2° ± 15.1° (range, 27.0°–74.3°, p = 0.048). The average cup positions for radiographic abduction angle and anteversion were 36.7° ± 8.9° (range, 24.5°–54.9°) and 29.1° ± 7.3° (range, 17.2°–38.8°), respectively (p > 0.05). Widmer's combined anteversion deviated from the target angle by a smaller amount in the navigation group than in the control group: errors in measurement of Widmer's combined anteversion were 7.2° ± 5.1° (range, 0.74°–19.6°) in the navigation group and 13.9° ± 11.1° (range, 3.6°–37.3°) in the control group (p = 0.135). Postoperative dislocation occurred in none of the 32 hips (0%) in the navigation group and in one of the 8 hips (12.5%) in the control group (p = 0.2).
Using the navigation system, combined anteversion is made near the target angle in isolated acetabular revision surgery and more accurately than manual implantation. These results should be considered as preliminary since this is a limited cohort, but it brings new knowledge in navigation considering the very limited number of series using of navigation in isolated cup revision of total hip arthroplasty. In addition this is the first study to investigate combined cup and stem anteversion in isolated acetabular revision. The use of CT-scan is helpful to diagnose error in stem anteversion and to adapt the orientation of the new cup.
III, Retrospective case control study.
A new and simple intraoperative method for correction of leg-length discrepancy in total hip arthroplasty
2019, Journal of Orthopaedics
Citation Excerpt :
Ogawa et al. used navigation to obtain positive results in 30 cases, reporting an intraoperative-postoperative error of 2.4 ± 1.7 mm.12 Other positive reports on navigation include a study by Kitada et al., who reported an error of 1.3 ± 4.1 mm in 16 cases, and a study by Ecker et al., who reported an error of 0.5 ± 1.7 mm in 344 cases.13,14 However, the high cost of navigation systems makes these methods less versatile.
Total hip arthroplasty (THA) can eliminate pain caused by hip joint destruction and correct leg-length discrepancies (LLD). We present a short and simple intraoperative method for LLD correction in THA. We performed 55 primary THAs using this technique. The measurement error was 1.86 ± 1.4 mm, which was within 3 mm in 49 of 55 cases (89%) and within 5 mm in 54 of 55 cases (98%). This method is simple and does not require specialized devices, making it versatile to be used anywhere. No new skin incisions or extra costs are required, which will likely make it attractive to surgeons.
Measurement accuracy of the acetabular cup position using an inertial portable hip navigation system with patients in the lateral decubitus position
2024, Scientific Reports
Accuracy of femoral component anteversion in robotic total hip arthroplasty A COMPARISON OF CEMENTED AND CEMENTLESS STEMS
2024, Bone and Joint Journal

View all citing articles on Scopus

: No benefits or funds were received in support of this study.

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Evaluation of the Accuracy of Computed Tomography–Based Navigation for Femoral Stem Orientation and Leg Length Discrepancy

Abstract

Section snippets

Materials and Methods

Results

Discussion

J Orthopaed Res

J Biomechanics

J Arthroplasty

J Arthroplasty

J Arthroplasty

J Arthroplasty

Computed tomography–based surgical navigation for hip arthroplasty

Clin Orthop Relat Res

Dislocations after total hip-replacement arthroplasties

J Bone Joint Surg Am

Mid-term results of cementless total hip replacement using a ceramic-on-ceramic bearing with and without computer navigation

J Bone Joint Surg Br

Management of limb length inequality during total hip replacement

Clin Orthop Relat Res

Surgical treatment of limb-length discrepancy following total hip arthroplasty

J Bone Joint Surg Am