Strategies in Trauma and Limb Reconstruction

Register      Login

VOLUME 17 , ISSUE 2 ( May-August, 2022 ) > List of Articles

Original Article

An MRI-based Study to Investigate If the Patella is Truly Centred between the Femoral Condyles in the Coronal Plane

Nihar S Shah, James C Kyriakedes, Raymond W Liu

Keywords : Guided growth, Hemiepiphysiodesis, Ideal knee radiograph, Lateral deviation of patella, Orthogonal imaging, Patellar centring

Citation Information : Shah NS, Kyriakedes JC, Liu RW. An MRI-based Study to Investigate If the Patella is Truly Centred between the Femoral Condyles in the Coronal Plane. 2022; 17 (2):63-67.

DOI: 10.5005/jp-journals-10080-1561

License: CC BY-NC-SA 4.0

Published Online: 28-07-2022

Copyright Statement:  Copyright © 2022; The Author(s).


Abstract

Background: An AP knee radiograph is considered adequate if the patella is centred between the femoral condyles. Our previous studies demonstrated a tendency for lateral patellar deviation on an AP view orthogonal to the posterior femoral condyles. However, findings were based on cadaveric samples limited by the lack of soft tissue effects on patellar positioning. Materials and methods: After excluding those with deformity or damage to osseous or ligamentous structures, 106 knee MRI scans were randomly selected. Patellar centring was calculated as a percentage of total distal femoral intercondylar width and represented how lateral the centre of the patella is located with respect to the midpoint of the femoral condyles. Multiple regression analysis was performed to determine the relationship between patellar centring and age, gender, anatomic lateral distal femoral angle (aLDFA), medial proximal tibial angle (MPTA) and tibial tuberosity to trochlear groove (TT-TG) distance. Results: There were 35 males and 71 females included in the study with a mean age of 29 ± 14 years. Mean patellar centring was 8 ± 4%. There was a statistically significant correlation between TT-TG distance and positive (lateral) patellar centring (standardised β = 0.36, p <0.01). There were no associations between aLDFA and MPTA with patellar centring. Conclusion: This study demonstrates that the patella is rarely perfectly centred and is usually positioned slightly laterally within the femoral condyles in an AP view orthogonal to the posterior aspect of the femoral condyles. The use of supine MRI scans makes this data relevant to a patient on the operating room table.


PDF Share
  1. Paley D. Principles of deformity correction. New York: Springer-Verlag; 2005. p. 1–18.
  2. Ajuwon AA, Desai R, Farhang K, et al. An anatomic study on whether the patella is centered in an ideal anteroposterior radiograph of the knee. HSS J 2015;11(2):117–122. DOI: 10.1007/s11420-014-9419-3.
  3. Kyriakedes JC, Liu RW. An anatomic study on whether the immature patella is centered on an anteroposterior radiograph. J Pediatr Orthop 2017;37(2):138–143. DOI: 10.1097/BPO.0000000000000687.
  4. Zaki R, Bulgiba A, Nordin N, et al. A systematic review of statistical methods used to test for reliability of medical instruments measuring continuous variables. Iran J Basic Med Sci 2013;16(6):803–807. PMID: 23997908.
  5. Pandit S, Frampton C, Stoddart J, et al. Magnetic resonance imaging assessment of tibial tuberosity-trochlear groove distance: normal values for males and females. Int Orthop 2011;35(12):1799–1803. DOI: 10.1007/s00264-011-1240-8.
  6. Hinckel BB, Gobbi RG, Filho ENK, et al. Are the osseous and tendinous-cartilaginous tibial tuberosity-trochlear groove distan- ces the same on CT and MRI? Skeletal Radiol 2015;44(8):1085–1093. DOI: 10.1007/s00256-015-2118-4.
  7. Prakash J, Seon JK, Ahn HW, et al. Factors affecting tibial tuberosity-trochlear groove distance in recurrent patellar dislocation. CiOS Clin Orthop Surg 2018;10(4):420–426. DOI: 10.4055/cios.2018.10.4.420.
  8. Kim HY, Kim KJ, Yang DS, et al. Screw-home movement of the tibiofemoral joint during normal gait: three-dimensional analysis. Clin Orthop Surg 2015;7(3):303–309. DOI: 10.4055/cios.2015.7.3.303.
  9. Levens AS, Inman VT, Blosser JA. Transverse rotation of the segments of the lower extremity in locomotion. J Bone Joint Surg Am 1948;30A(4):859–872. PMID: 18887290.
  10. Wright JG, Treble N, Feinstein AR. Measurement of lower limb alignment using long radiographs. J Bone Joint Surg Br 1991;73(5):721–723. DOI: 10.1302/0301-620X.73B5.1894657.
PDF Share
PDF Share

© Jaypee Brothers Medical Publishers (P) LTD.