Six-year outcome after non-surgical versus surgical treatment of acute primary patellar dislocation in adolescents: a prospective randomized trial

  • Gideon Regalado
  • Hannu Lintula
  • Hannu Kokki
  • Heikki Kröger
  • Urho Väätäinen
  • Matti EskelinenEmail author



There is only one prospective randomized trial on acute primary patellar dislocation in adolescents comparing the long-term outcome after conservative versus operative procedures. Therefore, the long-term outcome, patellar redislocation rate, and functional outcome after conservative versus operative procedures were investigated in a prospective randomized study.


Initially, 36 patients with acute primary patellar dislocation were prospectively randomized to conservative (n = 20) versus operative procedures (n = 16) and 30 of them (83 %), 15/20 with conservative and 15/16 with operative procedures, were reached for a follow-up interview 6 years after primary procedure.


Baseline and clinical parameters were similar in the two groups. The prevalence of patellar redislocation rate at 3 and 6 years after primary procedure was higher in the conservative group (7/20, 35 %, 3 years and 11/15, 73 %, 6 years) versus in the operative group (0/16, 0 %, 3 years and 5/15, 33 %, 6 years) (p = 0.02). The knee function was slightly better 6 years after primary treatment in the operative group than in the conservative group. Most patients in both groups had excellent or good knee function at 6-year follow-up, but four patients (4/15, 27 %) in conservative group and two patients (2/15, 13 %) in operative group had poor knee function at 6-year follow-up. Four patients in conservative group (4/15, 27 %) and two patients in the operative group (2/15, 13 %) were unsatisfied with the procedure at 6-year follow-up.


In conclusion, the results suggest that both conservative and operative procedures are feasible options for treatment of acute primary patellar dislocation in adolescents. A new finding with clinical relevance in the present work is a significantly higher redislocation rate in conservative group compared to operative group after 6-year follow-up in acute primary patellar dislocation in adolescents.

Level of evidence



Patellar dislocation Adolescents Treatment outcome Redislocation Randomized trial 



We thank Mrs Eeva Oittinen for the technical assistance. This work has been financially supported by EVO Grant from the Hospital District of Northern Savo, Finland.

Conflict of interest

Authors have no conflict of interest, and they have full control of all primary data. Authors allow the journal to review the data if requested.


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Copyright information

© European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA) 2014

Authors and Affiliations

  • Gideon Regalado
    • 1
  • Hannu Lintula
    • 2
  • Hannu Kokki
    • 2
    • 3
  • Heikki Kröger
    • 2
    • 4
  • Urho Väätäinen
    • 2
  • Matti Eskelinen
    • 2
    • 5
    Email author
  1. 1.Department of SurgerySouth Carelia HospitalLappeenrantaFinland
  2. 2.School of MedicineUniversity of Eastern FinlandKuopioFinland
  3. 3.Department of Anestesiology and Intensive CareKuopio University HospitalKuopioFinland
  4. 4.Department of OrthopedicsKuopio University HospitalKuopioFinland
  5. 5.Department of SurgeryKuopio University Hospital (KYS)KuopioFinland

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