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Conservative treatment is better than surgical management for first patellar dislocation

Three Part Question

In [patients with primary patellar dislocation] is [surgery better than conservative treatment] in [reducing symptoms and preventing redislocation]?

Clinical Scenario

A 20 year old woman presents to the emergency department having suffered her first lateral patellar dislocation 1 hour before. She has managed to reduce it herself. You wonder whether surgery is superior to conservative management.

Search Strategy

Medline 1966-06/99 using the OVID interface.
[({exp patella OR patella$.mp} AND {exp dislocations OR dislocate$.mp OR dislocation$.mp}) AND {exp emergency treatment OR exp treatment failure OR exp treatment outcome OR treatment$.mp}] AND maximally sensitive RCT filter) LIMIT to human and english.

Search Outcome

79 papers found of which 74 irrelevant and 3 of insufficient quality for inclusion. The remaining papers are shown in the table.

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses
Cash and Hughston
103 primary patellar dislocations over 30 years. Conservative treatment (74) vs athroscopy (13) alone vs arthrotomy (16) Subanalysis predisposed to dislocate (69) vs no predisposition (34)Retrospective cohortRecurrence rate (more than 1 redislocation)36.5% vs 23% vs 0Retrospective non- randomised series over 30 years. Very small numbers in some groups.
Recurrence rate (more than 1 redislocation) congenital predisposition vs noneConservative 43% vs 20%
Arthroscopy 0 vs 11%
Arthrotomy 0 vs 0
Nikku R et al
125 patients with acute primary patellar dislocation. Conservative (55) vs operative (70)PRCTInstability (redislocation or subluxation)No significant differenceRandomised by year of birth. Operations not standardised. All patients had EUA and arthroscopy prior to randomisation.
Patient opinionNo significant difference
Lysholm II scoreNo significant difference
Hughston VASNo significant difference
Number of major complications4 in operative group


There are a great number of single treatment case series in this area. Only one comparative series is randomised, and the surgical treatment is not standardised in either series. There is a suggestion that outcome may be different if there is a predisposition to dislocate but the evidence for this is very weak. Further work is required.

Clinical Bottom Line

Conservative management of primary patellar dislocation is as effective as surgery and has a lower complication rate. It is the treatment of choice.


  1. Cash JD and Hughston JC. Treatment of acute patellar dislocation. Am J Sports Med 1988;16:244-249.
  2. Nikku R, Nietosvaara Y, Kallio PE et al. Operative versus closed treatment of primary dislocation of the patella. Acta Orthop Scand 1997;68:419-423.