Acute Patellar Instability in Children

  • Stephen Ng Man Sun
  • Sally J. TennantEmail author


Acute patellar instability is part of the spectrum of patellofemoral maltracking problems, which can manifest as pain, subluxation or frank dislocation. Dislocation itself is usually the result of trauma, particularly in the presence of pre-existing structural abnormalities. Sequelae of acute dislocations include osteochondral injuries and recurrent instability; however, in the absence of osteochondral injuries or major morphological abnormalities, the gold standard of treatment is nonoperative. In this chapter, the patellofemoral joint anatomy is examined alongside the risk factors for instability. Causes of acute patellar instability are discussed, as well as management.


Acute patellar instability Dislocation Patellofemoral joint Diagnosis Treatment 


  1. 1.
    Redziniak DE, Diduch DR, Mihalko WM, Fulkerson JP, Novicoff WM, Sheibani-Rad S, et al. Patellar instability. J Bone Joint Surg Am. 2009;91:2264–75.PubMedGoogle Scholar
  2. 2.
    Vavken P, Wimmer MD, Camathias C, Quidde J, Valderrabano V, Pagenstert G. Treating patella instability in skeletally immature patients. Arthroscopy. 2013;29:1410–22.CrossRefGoogle Scholar
  3. 3.
    Colvin AC, West RV. Patellar instability. J Bone Joint Surg Am. 2008;90:2751–62.CrossRefGoogle Scholar
  4. 4.
    Apostolovic M, Vukomanovic B, Slavkovic N, Vuckovic V, Vukcevic M, Djuricic G, et al. Acute patellar dislocation in adolescents: operative versus nonoperative treatment. Int Orthop. 2011;35:1483–7.CrossRefGoogle Scholar
  5. 5.
    Sillanpaa P, Mattila VM, Iivonen T, Visuri T, Pihlajamaki H. Incidence and risk factors of acute traumatic primary patellar dislocation. Med Sci Sports Exerc. 2008;40:606–11.CrossRefGoogle Scholar
  6. 6.
    Hughston JC, Deese M. Medial subluxation of the patella as a complication of lateral retinacular release. Am J Sports Med. 1988;16:383–8.CrossRefGoogle Scholar
  7. 7.
    Insall J, Goldberg V, Salvati E. Recurrent dislocation and the high-riding patella. Clin Orthop Relat Res. 1972;88:67–9.CrossRefGoogle Scholar
  8. 8.
    Dejour H, Walch G, Nove-Josserand L, Guier C. Factors of patellar instability: an anatomic radiographic study. Knee Surg Sports Traumatol Arthrosc. 1994;2:19–26.CrossRefGoogle Scholar
  9. 9.
    Dejour H, Walch G, Neyret P, Adeleine P. Dysplasia of the femoral trochlea. Rev Chir Orthop Reparatrice Appar Mot. 1990;76:45–54.PubMedGoogle Scholar
  10. 10.
    Panni AS, Cerciello S, Maffulli N, Di Cesare M, Servien E, Neyret P. Patellar shape can be a predisposing factor in patellar instability. Knee Surg Sports Traumatol Arthrosc. 2011;19:663–70.CrossRefGoogle Scholar
  11. 11.
    Lewallen L, McIntosh A, Dahm D. First-time patellofemoral dislocation: risk factors for recurrent instability. J Knee Surg. 2015;28:303–9.CrossRefGoogle Scholar
  12. 12.
    Powers CM. The influence of altered lower-extremity kinematics on patellofemoral joint dysfunction: a theoretical perspective. J Orthop Sports Phys Ther. 2003;33:639–46.CrossRefGoogle Scholar
  13. 13.
    Reilly DT, Martens M. Experimental analysis of the quadriceps muscle force and patello-femoral joint reaction force for various activities. Acta Orthop Scand. 1972;43:126–37.CrossRefGoogle Scholar
  14. 14.
    Desio SM, Burks RT, Bachus KN. Soft tissue restraints to lateral patellar translation in the human knee. Am J Sports Med. 1998;26:59–65.CrossRefGoogle Scholar
  15. 15.
    Amis AA, Firer P, Mountney J, Senavongse W, Thomas NP. Anatomy and biomechanics of the medial patellofemoral ligament. Knee. 2003;10:215–20.CrossRefGoogle Scholar
  16. 16.
    Khormaee S, Kramer DE, Yen YM, Heyworth BE. Evaluation and management of patellar instability in pediatric and adolescent athletes. Sports Health. 2015;7:115–23.CrossRefGoogle Scholar
  17. 17.
    Larsen E, Lauridsen F. Conservative treatment of patellar dislocations. Influence of evident factors on the tendency to redislocation and the therapeutic result. Clin Orthop Relat Res. 1982;171:131–6.Google Scholar
  18. 18.
    Seeley MA, Knesek M, Vanderhave KL. Osteochondral injury after acute patellar dislocation in children and adolescents. J Pediatr Orthop. 2013;33:511–8.CrossRefGoogle Scholar
  19. 19.
    Smith TO, Donell S, Song F, Hing CB. Surgical versus non-surgical interventions for treating patellar dislocation. Cochrane Database Syst Rev. 2015:CD008106.Google Scholar
  20. 20.
    Nwachukwu BU, So C, Schairer WW, Green DW, Dodwell ER. Surgical versus conservative management of acute patellar dislocation in children and adolescents: a systematic review. Knee Surg Sports Traumatol Arthrosc. 2016;24:760–7.CrossRefGoogle Scholar
  21. 21.
    Erickson BJ, Mascarenhas R, Sayegh ET, Saltzman B, Verma NN, Bush-Joseph CA, et al. Does operative treatment of first-time patellar dislocations lead to increased patellofemoral stability? A systematic review of overlapping meta-analyses. Arthroscopy. 2015;31:1207–15.CrossRefGoogle Scholar
  22. 22.
    Cash JD, Hughston JC. Treatment of acute patellar dislocation. Am J Sports Med. 1988;16:244–9.CrossRefGoogle Scholar
  23. 23.
    Lun VM, Wiley JP, Meeuwisse WH, Yanagawa TL. Effectiveness of patellar bracing for treatment of patellofemoral pain syndrome. Clin J Sport Med. 2005;15:235–40.CrossRefGoogle Scholar
  24. 24.
    van Gemert JP, de Vree LM, Hessels RA, Gaakeer MI. Patellar dislocation: cylinder cast, splint or brace? An evidence-based review of the literature. Int J Emerg Med. 2012;5:45.CrossRefGoogle Scholar
  25. 25.
    Chester R, Smith TO, Sweeting D, Dixon J, Wood S, Song F. The relative timing of VMO and VL in the aetiology of anterior knee pain: a systematic review and meta-analysis. BMC Musculoskelet Disord. 2008;9:64.CrossRefGoogle Scholar
  26. 26.
    Buchner M, Baudendistel B, Sabo D, Schmitt H. Acute traumatic primary patellar dislocation: long-term results comparing conservative and surgical treatment. Clin J Sport Med. 2005;15:62–6.CrossRefGoogle Scholar
  27. 27.
    Arendt EA, Fithian DC, Cohen E. Current concepts of lateral patella dislocation. Clin Sports Med. 2002;21:499–519.CrossRefGoogle Scholar
  28. 28.
    Stefancin JJ, Parker RD. First-time traumatic patellar dislocation: a systematic review. Clin Orthop Relat Res. 2007;455:93–101.CrossRefGoogle Scholar
  29. 29.
    Beighton P, Solomon L, Soskolne CL. Articular mobility in an African population. Ann Rheum Dis. 1973;32:413–8.CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Royal National Orthopaedic Hospital NHS TrustStanmoreUK

Personalised recommendations