Knee Injuries - Patella Dislocation

Authors: Layla Abubshait, MD, Michael Gottlieb, MD, RDMS, Mary Haas, MD
Updated: 11/21/2016

Knee Injuries: Patella Dislocation

Patella dislocation drawing

X-ray Views

  • AP knee
  • Lateral knee: Best to assess for displacement
  • Patella view: Sunrise or Merchant view

Acute Management

  • Closed reduction
  • Splint in above-knee plaster cast (from distal 2/3s of thigh to MTP foot joints), straight leg immobilizer, or hinged knee brace
  • Weight-bearing as tolerated with crutches

Follow-up Timing

  • Within 1-2 weeks
  • Consider sooner follow-up to assess for associated osteochondral fractures and medial patellofemoral ligament injury, which may require operative repair.


  • Most managed non-operatively
  • Complications: Recurrent dislocations


  • Schwartz A. Patella Fractures Treatment & Management, (June 2016) [Source].
  • Hinton RY, Sharma KM. Acute and recurrent patellar instability in the young athlete. Orthop Clin North Am. 2003 Jul;34(3):385-96. [PubMed]
  • Ji G, et al . Surgical versus Nonsurgical Treatments of Acute Primary Patellar Dislocation with Special Emphasis on the MPFL Injury Patterns. J Knee Surg. 2016 Sep 14. Epub ahead of print. [PubMed]
  • Petri M, et al. Current Concepts for Patellar Dislocation. Arch Trauma Res. 2015 Sep 1;4(3):e29301. [PubMed]
  • Medina O, et al. Vascular and nerve injury after knee dislocation: a systematic review. Clin Orthop Relat Res. 2014 Sep;472(9):2621-9. [PubMed]