The Rationale for Tilt-Adjusted Acetabular Cup Navigation

Babisch, J.; Layher, Frank; Amiot, Louis-Philippe

doi:10.2106/jbjs.f.00628

Cited by 242 publications

(264 citation statements)

References 22 publications

Supporting

Mentioning

236

Contrasting

Unclassified

Order By: Relevance

“…Lembeck et al, in their cohort, observed a range of supine pelvic tilt from À17°to 3°, and standing pelvic tilt ranged from À27°to 3° [32]. Patients with hip disorders similarly have a wide range of individual pelvic tilt measurements [10], ranging greater than 60°in one study [39]. We (1) asked if acetabular anteversion measurements using the femoral head centers differed from those using the posterior ischia and (2) sought to understand the effects of changing obliquity, rotation, and tilt of a pelvis in a CT scanner on the measurement of acetabular variables.…”

Section: Discussionmentioning

confidence: 90%

Pelvic Positioning Creates Error in CT Acetabular Measurements

Bosse¹,

Lee

Henderson

et al. 2011

Clinical Orthopaedics &Amp; Related Research

View full text Add to dashboard Cite

Background CT allows for accurate measurement of acetabular orientation and shape, but malpositioning of the pelvis may lead to measurement variance. Purpose We therefore sought to determine: (1) whether acetabular anteversion measurements using the femoral head centers differed from those using the posterior ischia, and (2) the extent to which changing obliquity, rotation, and tilt of a pelvis in a CT scanner affected the measurement of acetabular variables. Methods A radiopaque human pelvis model with articulated hips was suspended from a plastic sheet as part of an adjustable frame. Changes in the transverse and sagittal planes created rotation and tilt, while rotating the frame in the coronal plane created obliquity. CT scans were obtained, varying the combinations of obliquity, rotation, and tilt by intervals of 5°, up to 20°. Acetabular anteversion (AA), anterior acetabular sector angle (AASA), posterior acetabular sector angle (PASA), and horizontal acetabular sector angle (HASA) were measured. Results The two methods for measuring AA yielded values differing by 1°to 4°but correlated (r = 0.981) across the spectrum of pelvis positioning. Pelvic obliquity and tilt were linearly associated with changes in the measurements. For each 1°-increase in pelvic obliquity, AA changed À0.4°, and AASA, PASA, and HASA changed 1.93°, 0.99°, and 2.80°, respectively. For each 1°-increase in pelvic tilt, AA changed 0.8°, and AASA, PASA, and HASA changed À1.07°, 0.52°, and À0.51°, respectively. Rotation had no affect on the variables. Conclusions Small changes in pelvic obliquity and tilt were associated with variances in acetabular measurements. The measured changes were directly proportional to the changes in obliquity and tilt, and were additive. Pelvic rotation created no changes in measurement. Clinical Relevance Incorrect interpretation of acetabular anteversion and coverage may lead to unsatisfactory acetabular fragment positioning during reorientational surgery. Although intraoperative positioning of an acetabular fragment may not be as precise as the tools for preoperative planning, it is important for a surgeon to have the most precise data available for planning a procedure, and know where error can occur in collecting the data.Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article.

show abstract

Section: Discussionmentioning

confidence: 90%

Pelvic Positioning Creates Error in CT Acetabular Measurements

Bosse¹,

Lee

Henderson

et al. 2011

Clinical Orthopaedics &Amp; Related Research

View full text Add to dashboard Cite

show abstract

“…A rough estimation of pelvic rotation on AP radiographs may be done using the Tönnis' foramen obturator index [29,30]. By approximation, pelvic tilt may be assessed by e. g. the coccygeal-symphysis index on AP radiographs [24], but for exact angular information lateral radiographs of the pelvis are necessary [22]. A second limitation is our experimental setup.…”

Section: Discussionmentioning

confidence: 99%

“…Similar to the definition of Babisch [22], pelvic tilt was defined as the angle between the vertical functional coronary plane (FCP) and the anterior pelvis plane (APP) (▶ Fig. 2).…”

Section: Experiments For Pelvic Tiltmentioning

confidence: 99%

“…Assessment of cup orientation in the APP is necessary when computer navigation is used for improving the range of motion in THA [2]. Babisch used normograms to convert values of cup position from the APP to the coronal plane [22]. Similar to our correction method, Wan and Lembeck also used a mathematical solution to transfer values of cup position from one reference plane to another reference plane [23,25].…”

Section: Op-videomentioning

confidence: 99%

“…1°of pelvic tilt may change anteversion by 0.8° [21]. Several methods using normograms [22] or mathematical equations [23 -25] have been developed for compensating errors due to pelvic tilt. To the best of our knowledge, no corrective calculation can yet compensate errors due to central beam offset, pelvic tilt, and pelvic rotation in one procedure.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Correction of Pelvic Tilt and Pelvic Rotation in Cup Measurement after THA – An Experimental Study

Schwarz¹,

Weber²,

Dornia

et al. 2017

Fortschr Röntgenstr

View full text Add to dashboard Cite

ZUSAMMENFASSUNGZiel Nach Hüft-TEP-Versorgungen ist die korrekte Vermessung der Pfannenstellung in postoperativen Röntgenaufnah-men wichtig für die Qualitätskontrolle. In dieser Studie stellen wir eine neue Methode vor, mit der wir Messungenauigkeiten, die sich durch die Beckenverkippung und -verdrehung ergeben, korrigieren können.Methode In einem experimentellen Ansatz implantierten wir eine Prothesenpfanne in ein Kunststoffbecken und bestimmten die tatsächliche Pfannenstellung in einer CT. Um die Auswirkung der Beckenverkippung und -verdrehung auf die Pfannenstellung in AP Röntgenbildern darzustellen, wurde das Becken auf einer Halterung fixiert, mit der eine graduelle Vor-und Rückwärts-Kippung (± 15°) sowie eine Beckenverdrehung (0°bis 20°zur Gegenseite) umgesetzt werden konnte. Zur Korrektur von Messfehlern, die sich aus der Beckenverkippung und -rotation ergeben, entwickelten wir gemäß der Definitionen der Anteversion und Inklination nach Murray ein neues Korrekturverfahren, mit dem die Pfannenstellung in einem Becken bezogenen Koordinatensystem (Anterior Pelvic Plane) vermessen werden kann. This document was downloaded for personal use only. Unauthorized distribution is strictly prohibited. ABSTR AC TPurpose Accurate assessment of cup orientation on postoperative pelvic radiographs is essential for evaluating outcome after THA. Here, we present a novel method for correcting measurement inaccuracies due to pelvic tilt and rotation.Method In an experimental setting, a cup was implanted into a dummy pelvis, and its final position was verified via CT. To show the effect of pelvic tilt and rotation on cup position, the dummy was fixed to a rack to achieve a tilt between + 15°a nterior and -15°posterior and 0°to 20°rotation to the contralateral side. According to Murray's definitions of anteversion and inclination, we created a novel corrective procedure to measure cup position in the pelvic reference frame (anterior pelvic plane) to compensate measurement errors due to pelvic tilt and rotation.Results The cup anteversion measured on CT was 23.3°; on AP pelvic radiographs, however, variations in pelvic tilt (± 15°) resulted in anteversion angles between 11.0°and 36.2°(mean error 8.3°± 3.9°). The cup inclination was 34.1°o n CT and ranged between 31.0°and 38.7°(m. e. 2.3°± 1.5°) on radiographs. Pelvic rotation between 0°and 20°showed high variation in radiographic anteversion (21.2°-31.2°, m. e. 6.0°± 3.1°) and inclination (34.1°-27.2°, m. e. 3.4°± 2.5°). Our novel correction algorithm for pelvic tilt reduced the mean error in anteversion measurements to 0.6°± 0.2°and in inclination measurements to 0.7°(SD± 0.2). Similarly, the mean error due to pelvic rotation was reduced to 0.4°± 0.4°for anteversion and to 1.3°± 0.8 for inclination.

show abstract

Computer Navigation in Total Hip Arthroplasty

Malik

Dorr

2021

Evidence‐Based Orthopedics

View full text Add to dashboard Cite

The Rationale for Tilt-Adjusted Acetabular Cup Navigation

Cited by 242 publications

References 22 publications

Pelvic Positioning Creates Error in CT Acetabular Measurements

Pelvic Positioning Creates Error in CT Acetabular Measurements

Correction of Pelvic Tilt and Pelvic Rotation in Cup Measurement after THA – An Experimental Study

Computer Navigation in Total Hip Arthroplasty

Contact Info

Product

Resources

About