Quantitative magnetic resonance imaging in patellar tendon-lateral femoral condyle friction syndrome: relationship with subtle patellofemoral instability



To investigate the correlation of patellar tendon-lateral femoral condyle friction syndrome (PTLFCFS) with subtle patellofemoral instability to explore its pathogenesis.

Materials and methods

One hundred knees of 80 patients with PTLFCFS were analyzed retrospectively by retrieving magnetic resonance imaging (MRI) data over a 3-year period from our database. Seven quantitative parameters for evaluating patellofemoral stability were measured on MR images, including the Insall–Salvati ratio, tibial tuberosity–trochlear groove (TT–TG) distance, trochlear groove depth, medial trochlear/lateral trochlear length (MT/LT) ratio, medial trochlear/lateral trochlear height (MH/LH) ratio, lateral patellofemoral angle (LPA), and lateral trochlear inclination (LTI) angle. These patellofemoral parameters of the PTLFCFS group and the normal control group were compared (n = 88), and receiving-operator characteristic (ROC) curve analysis was conducted to determine the specificity and sensitivity of these parameters.


The trochlear depth, MT/LT, LPA, and LTI angle were significantly lower (p < 0.001) and the Insall–Salvati ratio was significantly higher (p < 0.001) in the PTLFCFS group. However, the TT–TG distance and MH/LH ratio showed no significant difference (p = 0.231 and 0.073 respectively). The area under the ROC curve of the Insall–Salvati ratio, trochlear depth, MT/LT, LPA, and LTI angle were 0.925, 0.784, 0.8, 0.731, and 0.675 respectively. The efficiency of the Insall–Salvati ratio was the highest among those five parameters.


This study verified the presence of subtle patellofemoral instability by measuring various patellofemoral parameters in patients with PTLFCFS. It confirmed that PTLFCFS is associated with subtle patellofemoral instability and could largely explain the pathogenesis of PTLFCFS.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2
Fig. 3


  1. 1.

    Senavongse W, Amis AA. The effects of articular, retinacular, or muscular deficiencies on patellofemoral joint stability: a biomechanical study in vitro. J Bone Joint Surg Br. 2005;87(4):577–82.

    CAS  Article  Google Scholar 

  2. 2.

    Dragoo JL, Johnson C, McConnell J. Evaluation and treatment of disorders of the infrapatellar fat pad. Sports Med. 2012;42(1):51–67.

    Article  Google Scholar 

  3. 3.

    Mehta K, Wissman R, Englang E, D’heurle A, Newton K, Kenter K. Superolateral Hoffa’s fat pad edema in collegiate volleyball players. J Comput Assist Tomogr. 2015;39(6):945–50.

    Article  Google Scholar 

  4. 4.

    Fontanella CG, Carniel EL, Frigo A, Macchi V, Porzionato A, Sarasin G, et al. Investigation of biomechanical response of Hoffa's fat pad and comparative characterization. J Mech Behav Biomed Mater. 2017;67:1–9.

    Article  Google Scholar 

  5. 5.

    Biedert RM, Sanchis-Alfonso V. Sources of anterior knee pain. Clin Sports Med. 2002;21(3):335–47.

    Article  Google Scholar 

  6. 6.

    Clockaerts S, Bastiaansen-Jenniskens YM, Runhaar J, Van Osch GJ, Van Offel JF, Verhaar JA, et al. The infrapatellar fat pad should be considered as an active osteoarthritic joint tissue: a narrative review. Osteoarthritis Cartilage. 2010;18(7):876–82.

    CAS  Article  Google Scholar 

  7. 7.

    Subhawong TK, Eng J, Carrino JA, Chhabra A. Superolateral Hoffa’s fat pad edema: association with patellofemoral maltracking and impingement. AJR Am J Roentgenol. 2010;195(6):1367–73.

    Article  Google Scholar 

  8. 8.

    Barbier-Brion B, Lerais JM, Aubry S, Lepage D, Vidal C, Delabrousse E, et al. Magnetic resonance imaging in patellar lateral femoral friction syndrome (PLFFS): prospective case-control study. Diagn Interv Imaging. 2012;93:e171–82.

    CAS  Article  Google Scholar 

  9. 9.

    Chhabra A, Subhawong TK, Carrino JA. A systematised MRI approach to evaluating the patellofemoral joint. Skeletal Radiol. 2011;40(4):375–87.

    Article  Google Scholar 

  10. 10.

    Chung CB, Skaf A, Roger B, Campos J, Stump X, Resnick D. Patellar tendon-lateral femoral condyle friction syndrome: MR imaging in 42 patients. Skeletal Radiol. 2001;30(12):694–7.

    CAS  Article  Google Scholar 

  11. 11.

    Jibri Z, Martin D, Mansour R, Kamath S. The association of infrapatellar fat pad oedema with patellar maltracking: a case–control study. Skeletal Radiol. 2012;41(8):925–31.

    Article  Google Scholar 

  12. 12.

    Campagna R, Pessis E, Biau DJ, Guerini H, Feydy A, Thevenin FS, et al. Is superolateral Hoffa fat pad edema a consequence of impingement between lateral femoral condyle and patellar ligament? Radiology. 2012;263(2):469–74.

    Article  Google Scholar 

  13. 13.

    Matcuk GR Jr, Cen SY, Keyfes V, Patel DB, Gottsegen CJ, White EA. Supero-lateral Hoffa fat pad edema and patellofemoral maltracking: predictive modeling. AJR Am J Roentgenol. 2014;203(2):207–12.

    Article  Google Scholar 

  14. 14.

    Insall J, Salvati E. Patella position in the normal knee joint. Radiology. 1971;101(1):101–4.

    CAS  Article  Google Scholar 

  15. 15.

    Carrillon Y, Abidi H, Dejour D, Fantino O, Moyen B, Tran-Minh VA. Patellar instability: assessment on MR images by measuring the lateral trochlear inclination—initial experience. Radiology. 2000;216(2):582–5.

    CAS  Article  Google Scholar 

  16. 16.

    Duchman K, Mellecker C, Thedens DR, Albright JP. Quantifying the effects of extensor mechanism medialization procedures using MRI: a cadaver-based study. Iowa Orthop J. 2011;31:90–8.

    PubMed  PubMed Central  Google Scholar 

  17. 17.

    Schoettle PB, Zanetti M, Seifert B, Pfirrmann CW, Fucentese SF, Romero J. The tibial tuberosity-trochlear groove distance; a comparative study between CT and MRI scanning. Knee. 2006;13(1):26–31.

    Article  Google Scholar 

  18. 18.

    Song EK, Seon JK, Kim MC, Seol YJ, Lee SH. Radiologic measurement of Tibial tuberosity-trochlear groove (TT-TG) distance by lower extremity rotational profile computed tomography in Koreans. Clin Orthop Surg. 2016;8(1):45–8.

    Article  Google Scholar 

  19. 19.

    Wittstein JR, Bartlett EC, Easterbrook J, Byrd JC. Magnetic resonance imaging evaluation of patellofemoral malalignment. Arthroscopy. 2006;22(6):643–9.

    Article  Google Scholar 

  20. 20.

    Lake DA, Wofford NH. Effect of therapeutic modalities on patients with patellofemoral pain syndrome: a systematic review. Sports Health. 2011;3(2):182–9.

    Article  Google Scholar 

  21. 21.

    AL-Sayyad MJ, Cameron JC. Functional outcome after tibial tubercle transfer for the painful patella alta. Clin Orthop. 2002;396:152–62.

    Article  Google Scholar 

  22. 22.

    Munch JL, Sullivan JP, Nguyen JT, Mintz D, Green DW, Shubin Stein BE, et al. Patellar articular overlap on MRI is a simple alternative to conventional measurements of patellar height. Orthop J Sports Med. 2016;4(7):2325967116656328.

    Article  Google Scholar 

  23. 23.

    Bonadio MB, Helito CP, do Prado Torres JA, Gobbi RG, Pecora JR, Camanho GL, et al. Plateau–patella angle: an option for the evaluation of patellar height in patients with patellar instability. Knee. 2017;24:340–4.

    Article  Google Scholar 

  24. 24.

    Harbaugh CM, Wilson NA, Sheehan FT. Correlating femoral shape with patellar kinematics in patients with patellofemoral pain. J Orthop Res. 2010;28(7):865–72.

    PubMed  PubMed Central  Google Scholar 

  25. 25.

    Keser S, Savranlar A, Bayar A, Ege A, Turhan E. Is there a relationship between anterior knee pain and femoral trochlear dysplasia? Assessment of lateral trochlear inclination by magnetic resonance imaging. Knee Surg Sports Traumatol Arthrosc. 2008;16(10):911–5.

    Article  Google Scholar 

  26. 26.

    Balcarek P, Jung K, Ammon J, Walde TA, Frosch S, Schüttrumpf JP, et al. Anatomy of lateral patellar instability: trochlear dysplasia and tibial tubercle-trochlear groove distance is more pronounced in women who dislocate the patella. Am J Sports Med. 2010;38(11):2320–7.

    Article  Google Scholar 

  27. 27.

    Balcarek P, Jung K, Frosch KH, Stürmer KM. Value of the tibial tuberosity-trochlear groove distance in patellar instability in the young athlete. Am J Sports Med. 2011;39(8):1756–61.

    Article  Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Haitao Yang.

Ethics declarations

Conflicts of interest

The authors declare that they have no conflicts of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Li, J., Sheng, B., Yu, F. et al. Quantitative magnetic resonance imaging in patellar tendon-lateral femoral condyle friction syndrome: relationship with subtle patellofemoral instability. Skeletal Radiol 48, 1251–1259 (2019). https://doi.org/10.1007/s00256-019-3163-1

Download citation


  • Knee joint
  • Magnetic resonance imaging
  • Patellar tendon
  • Hoffa’s fat-pad edema
  • Patellofemoral instability