Knee Surgery, Sports Traumatology, Arthroscopy

, Volume 25, Issue 8, pp 2352–2356 | Cite as

Primary patellar dislocations without surgical stabilization or recurrence: how well are these patients really doing?

  • Robert A. MagnussenEmail author
  • Megan Verlage
  • Elizabeth Stock
  • Lauren Zurek
  • David C. Flanigan
  • Marc Tompkins
  • Julie Agel
  • Elizabeth A. Arendt



While a significant research has gone into identifying patients at highest risk of recurrence following primary patellar dislocation, there has been little work exploring the outcomes of patients who do not have a recurrent patellar dislocation. We hypothesize that patients without recurrent dislocation episodes will exhibit significantly higher KOOSs than those who suffer recurrent dislocations, but lower scores than published age-matched normative data.


A retrospective review of patients with nonoperatively treated primary lateral patellar dislocations was carried out, and patients were contacted at a mean of 3.4 years (range 1.3–5.5 years) post-injury. Information regarding subsequent treatment and recurrent dislocations along with patient-reported outcome scores and activity level was collected.


One hundred and eleven patients (29.8 %) of 373 eligible patients agreed to study participation, seven of whom were excluded because they underwent subsequent patellar stabilization surgery on the index knee. Seventy-six patients (73.1 %) reported no further dislocation events, and the mean KOOS subscales at follow-up were: symptoms—80.2 ± 18.8, pain—81.8 ± 16.2, ADL—88.7 ± 15.9, sport/recreation—72.1 ± 24.4, and QOL—63.9 ± 23.8 at a mean follow-up of 3.3 years (range 1.3–5.5 years). No significant differences in any of the KOOS subscales were noted between these patients and the group that reported recurrent patellar dislocations. Only 26.4 % of the patients without further dislocations reported they were able to return to desired sport activities without limitations following their dislocation.


Patients who do not report recurrent patellar dislocations following nonoperative treatment of primary patellar dislocations are in many cases limited by this injury 3 years following the initial dislocation event.

Level of evidence

Retrospective cohort study, Level III.


Patellar instability Nonoperative Patient-reported outcomes 


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Copyright information

© European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA) 2015

Authors and Affiliations

  • Robert A. Magnussen
    • 1
    • 2
    Email author
  • Megan Verlage
    • 1
  • Elizabeth Stock
    • 3
  • Lauren Zurek
    • 3
  • David C. Flanigan
    • 1
    • 2
  • Marc Tompkins
    • 3
    • 4
  • Julie Agel
    • 3
  • Elizabeth A. Arendt
    • 3
  1. 1.Department of Orthopaedics, Sports Health and Performance InstituteThe Ohio State UniversityColumbusUSA
  2. 2.Sports Health and Performance InstituteThe Ohio State UniversityColumbusUSA
  3. 3.Department of Orthopaedic SurgeryUniversity of MinnesotaMinneapolisUSA
  4. 4.TRIA Orthopaedic CenterBloomingtonUSA

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