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Is Vertical-center-anterior Angle Equivalent to Anterior Coverage of the Hip?

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Clinical Orthopaedics and Related Research®

Abstract

We investigated whether the vertical-center-anterior (VCA) angle measured on the false-profile view of the hip represents true anterior coverage by computer simulation using three-dimensional (3-D) computed tomography (CT) in 100 hips without osteoarthritic changes. True anterior coverage angle on the sagittal plane was measured in the pelvic coordinate system. Two types of VCA angle were measured on the digital reconstructed radiographs: the anterior point of the VCA angle was defined as the foremost aspect of the acetabulum, denoted VCA-1, whereas the anterior edge of the dense shadow of the subchondral bone of the acetabulum was defined as VCA-2. In the normal hips, VCA-1 was consistent with anterior coverage angle (r = 0.88, Spearman rank test), whereas VCA-2 underestimated the anterior coverage (r = 0.72). In the dysplastic hips, VCA-2 did not always indicate true anterior coverage (r = 0.64), whereas VCA-1 overestimated the anterior coverage (r = 0.002). Although VCA-1 in normal hips shows true anterior coverage, the VCA angle does not indicate true anterior coverage in dysplastic hips, and VCA angle measurement in dysplastic hips should be used carefully.

Level of Evidence: Level IV, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

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References

  1. Anda S, Svenningsen S, Grontvedt T, Benum P. Pelvic inclination and spatial orientation of the acetabulum: a radiographic, computed tomographic and clinical investigation. Acta Radiol. 1990;31:389–394.

    Article  PubMed  CAS  Google Scholar 

  2. Chosa E, Tajima N. Anterior acetabular head index of the hip on false-profile views: new index of anterior acetabular cover. J Bone Joint Surg Br. 2003;85:826–829.

    PubMed  Google Scholar 

  3. Chosa E, Tajima N, Nagatsuru Y. Evaluation of acetabular coverage of the femoral head with anteroposterior and false profile radiographs of hip joint. J Orthop Sci. 1997;2:378–390.

    Article  Google Scholar 

  4. Crockarell JR Jr, Trousdale RT, Guyton JL. The anterior center-edge angle: a cadaver study. J Bone Joint Surg Br. 2000;82:532–534.

    Article  PubMed  Google Scholar 

  5. Ito K, Minka MA 2nd, Leunig M, Werlen S, Ganz R. Femoroacetabular impingement and cam-effect: a MRI-based quantitative anatomical study of the femoral head-neck offset. J Bone Joint Surg Br. 2001;83:171–176.

    Article  PubMed  CAS  Google Scholar 

  6. Kojima A, Nakagawa T, Tohkura A. Simulation of acetabular coverage of femoral head using anteroposterior pelvic radiographs. Arch Orthop Trauma Surg. 1998;117:330–336.

    Article  PubMed  CAS  Google Scholar 

  7. Konishi N, Mieno T. Determination of acetabular coverage of the femoral head with use of a single anteroposterior radiograph: a new computerized technique. J Bone Joint Surg Am. 1993;75:1318–1333.

    PubMed  CAS  Google Scholar 

  8. Lembeck B, Mueller O, Reize P, Wuelker N. Pelvic tilt makes acetabular cup navigation inaccurate. Acta Orthop. 2005;76:517–523.

    Article  PubMed  Google Scholar 

  9. Lequesne M, de Seze S. The false-profile view of the hip: new radiographic method of the hip evaluation and the utility for the diagnosis of the dysplasia and different coxopathy [in French]. Rev Rhum. 1961;28:643–652.

    PubMed  CAS  Google Scholar 

  10. Li PLS, Ganz R. Morphologic features of congenital acetabular dysplasia: one of six is retroverted. Clin Orthop Relat Res. 2005;416:245–253.

    Article  Google Scholar 

  11. Mayr E, Kessler O, Prassl A, Rachbauer F, Krismer M, Nogler M. The frontal pelvic plane provides a valid reference system for implantation of the acetabular cup: spatial orientation of the pelvis in different positions. Acta Orthop. 2005;76:848–853.

    Article  PubMed  Google Scholar 

  12. Milcan A, Yildiz A, Oztuna V, Eskandari MM, Sahin G, Kuyurtar F. The anterior center edge angle: a study of 120 volunteers. Joint Bone Spine. 2004;71:221–223.

    Article  PubMed  Google Scholar 

  13. Sharp IK. Acetabular dysplasia: the acetabular angle. J Bone Joint Surg Br. 1961;43:268–272.

    Google Scholar 

  14. Sugano N, Nishii T, Takao M. The Asian hip. In: Callaghan JJ, Rosenberg AG, Rubash HE, eds. The Adult Hip. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2007:1060–1077.

    Google Scholar 

  15. Wiberg G. Studies on dysplastic acetabula and congenital subluxation of the hip joint with special reference to the complication of osteoarthritis. Acta Chir Scand Suppl. 1939;83:1–130.

    Google Scholar 

  16. Wu G, Siegler S, Allard P, Kirtley C, Leardini A, Rosenbaum D, Whittle M, D’Lima DD, Cristofolini L, Witte H, Schmid O, Stokes I; Standardization and Terminology Committee of the International Society of Biomechanics. ISB recommendation on definitions of joint coordinate system of various joints for the reporting of human joint motion: Part I: ankle, hip, and spine. International Society of Biomechanics. J Biomech. 2002;35:543–548.

    Article  PubMed  Google Scholar 

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Acknowledgments

We thank Mr. Ryoji Nakao, Dr. Kunihiro Oka, and Dr. Tsuyoshi Murase for technical support. We also thank Dr. Shunsaku Nishihara and Dr. Masaki Takao for helpful advice.

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Correspondence to Takashi Sakai MD, PhD.

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One of the authors (KS) has received funding from the Japanese Science and Technology Agency.

Each author certifies that his or her institution has approved the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research.

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Sakai, T., Nishii, T., Sugamoto, K. et al. Is Vertical-center-anterior Angle Equivalent to Anterior Coverage of the Hip?. Clin Orthop Relat Res 467, 2865–2871 (2009). https://doi.org/10.1007/s11999-009-0802-1

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  • DOI: https://doi.org/10.1007/s11999-009-0802-1

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