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Skeletal Radiology

, Volume 48, Issue 5, pp 707–712 | Cite as

3D hindfoot alignment measurements based on low-dose biplanar radiographs: a clinical feasibility study

  • Andrea B. RosskopfEmail author
  • Reto Sutter
  • Christian W. A. Pfirrmann
  • Florian M. Buck
Scientific Article

Abstract

Objective

To test a 3D-hindfoot alignment (HA) measurement technique based on low-dose biplanar radiographs (BPRs) in a clinical setting and compare the results with 2D-HA measurements on long axial view radiographs (LARs).

Materials and methods

This prospective study was approved by the local institutional review board. HA measurements on 3D-BPR and 2D-LAR of 50 patients (29 female; mean age 47 ± 16.6 years) were compared (positive values = valgus; negative values = varus). Two independent musculoskeletal radiologists (readers 1 and 2) performed 3D-HA measurements on BPR using a custom-made MATLAB code and measured HA on LAR during two separate readout sessions. Descriptive statistics and intraclass correlation coefficients (ICC) were calculated, and Bland–Altman plots were used for intermethod comparison.

Results

Using BPRs, HA was 0.8° ± 9.°1 (range, −20.2 to 20.0) for reader 1, and 0.7° ± 9.5° (range, −21.2 to 18.3) for reader 2. HA on LARs was −2.0 ° ± 7.0° (range, −27.0° to 11.1°) for reader 1 and − 1.7° ± 7.0° (range, −24.1° to 14.3°) for reader 2. Interreader agreement for measurements was excellent, both for BPRs (ICC = 0.992; 95% CI:0.986–0.995) and LAR measurements (ICC = 0.962; 95% CI:0.932–0.978). Mean difference between the two methods was −2.43° (range, −29.4° to 25.6°) for reader 1 and −2.6° (range,-28.7° to 30.2°) for reader 2. On Bland–Altman plots, three measurements of reader 1 and six measurements of reader 2 were outside of the ±1.96 SD interval.

Conclusion

Hindfoot alignment measurements on 3D-BPR have an excellent interreader agreement in a clinical setting. Large measurement errors can occur in individual patients using 2D-LAR alone. Therefore, we suggest using 3D-BPR measurements in daily routine for the assessment of HA, which are independent of rotational foot malpositioning.

Keywords

Biplanar radiographs Hindfoot Alignment Long axial view Ankle 

Notes

Compliance with ethical standards

Conflicts of interest

The authors declare that they have no conflicts of interest. The authors did not receive any financial benefits from EOS.

References

  1. 1.
    Krause FG, Iselin LD. Hindfoot varus and neurologic disorders. Foot Ankle Clin. 2012;17(1):39–56.CrossRefGoogle Scholar
  2. 2.
    Larsen E, Angermann P. Association of ankle instability and foot deformity. Acta Orthop Scand. 1990;61(2):136–9.CrossRefGoogle Scholar
  3. 3.
    Lamm BM, Mendicino RW, Catanzariti AR, Hillstrom HJ. Static rearfoot alignment: a comparison of clinical and radiographic measures. J Am Podiatr Med Assoc. 2005;95(1):26–33.CrossRefGoogle Scholar
  4. 4.
    Norton AA, Callaghan JJ, Amendola A, Phisitkul P, Wongsak S, Liu SS, et al. Correlation of knee and hindfoot deformities in advanced knee OA: compensatory hindfoot alignment and where it occurs. Clin Orthop Relat Res. 2015;473(1):166–74.CrossRefGoogle Scholar
  5. 5.
    Ohnishi T, Hida M, Nakamura Y, Wada C. Novel method for evaluation of hindfoot alignment in weight-bearing position using laser beam. J Phys Ther Sci. 2018;30(3):474–8.CrossRefGoogle Scholar
  6. 6.
    Thapa MM, Pruthi S, Chew FS. Radiographic assessment of pediatric foot alignment: review. AJR Am J Roentgenol. 2010;194(6 Suppl):S51–8.CrossRefGoogle Scholar
  7. 7.
    Sutter R, Pfirrmann CW, Espinosa N, Buck FM. Three-dimensional hindfoot alignment measurements based on biplanar radiographs: comparison with standard radiographic measurements. Skeletal Radiol. 2013;42(4):493–8.CrossRefGoogle Scholar
  8. 8.
    Frigg A, Nigg B, Hinz L, Valderrabano V, Russell I. Clinical relevance of hindfoot alignment view in total ankle replacement. Foot Ankle Int. 2010;31(10):871–9.CrossRefGoogle Scholar
  9. 9.
    Saltzman CL, el-Khoury GY. The hindfoot alignment view. Foot Ankle Int. 1995;16(9):572–6.CrossRefGoogle Scholar
  10. 10.
    Williamson ER, Chan JY, Burket JC, Deland JT, Ellis SJ. New radiographic parameter assessing hindfoot alignment in stage II adult-acquired flatfoot deformity. Foot Ankle Int. 2015;36(4):417–23.CrossRefGoogle Scholar
  11. 11.
    Johnson JE, Lamdan R, Granberry WF, Harris GF, Carrera GF. Hindfoot coronal alignment: a modified radiographic method. Foot Ankle Int. 1999;20(12):818–25.CrossRefGoogle Scholar
  12. 12.
    Reilingh ML, Beimers L, Tuijthof GJ, Stufkens SA, Maas M, van Dijk CN. Measuring hindfoot alignment radiographically: the long axial view is more reliable than the hindfoot alignment view. Skeletal Radiol. 2010;39(11):1103–8.CrossRefGoogle Scholar
  13. 13.
    Buck FM, Hoffmann A, Mamisch-Saupe N, Espinosa N, Resnick D, Hodler J. Hindfoot alignment measurements: rotation-stability of measurement techniques on hindfoot alignment view and long axial view radiographs. AJR Am J Roentgenol. 2011;197(3):578–82.CrossRefGoogle Scholar
  14. 14.
    Hirschmann A, Pfirrmann CW, Klammer G, Espinosa N, Buck FM. Upright cone CT of the hindfoot: comparison of the non-weight-bearing with the upright weight-bearing position. Eur Radiol. 2014;24(3):553–8.CrossRefGoogle Scholar
  15. 15.
    Burssens A, Peeters J, Buedts K, Victor J, Vandeputte G. Measuring hindfoot alignment in weight bearing CT: a novel clinical relevant measurement method. Foot Ankle Surg. 2016;22(4):233–8.CrossRefGoogle Scholar
  16. 16.
    Melhem E, Assi A, El Rachkidi R, Ghanem I. EOS((R)) biplanar X-ray imaging: concept, developments, benefits, and limitations. J Child Orthop. 2016;10(1):1–14.CrossRefGoogle Scholar
  17. 17.
    Rosskopf AB, Pfirrmann CW, Buck FM. Assessment of two-dimensional (2D) and three-dimensional (3D) lower limb measurements in adults: comparison of micro-dose and low-dose biplanar radiographs. Eur Radiol. 2016;26(9):3054–62.CrossRefGoogle Scholar
  18. 18.
    Mettler FA Jr, Huda W, Yoshizumi TT, Mahesh M. Effective doses in radiology and diagnostic nuclear medicine: a catalog. Radiology. 2008;248(1):254–63.CrossRefGoogle Scholar

Copyright information

© ISS 2018

Authors and Affiliations

  • Andrea B. Rosskopf
    • 1
    • 2
    Email author
  • Reto Sutter
    • 1
    • 2
  • Christian W. A. Pfirrmann
    • 1
    • 2
  • Florian M. Buck
    • 1
    • 2
  1. 1.RadiologyBalgrist University HospitalZurichSwitzerland
  2. 2.Faculty of MedicineUniversity of ZurichZurichSwitzerland

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