title: The fabella syndrome - a rare cause of posterolateral knee pain: a review of the literature and two case reports.
abstract: BACKGROUND
  The purpose of this article was to evaluate the risks and benefits of non-operative treatment versus surgical excision of a fabella causing posterolateral knee pain. We performed a systematic review of literature and also present two case reports.Twelve publications were found in a PubMed literature review searching the word "fabella syndrome". Non-operative treatment and surgical excision of the fabella has been described.
  
  
  METHODS
  Two patients presented to our outpatient clinic with persisting posterolateral knee pain. In both cases the presence of a fabella was identified, located in close proximity to the posterolateral femoral condyle. All other common causes of intra- and extra articular pathologies possibly causing the posterolateral knee pain were excluded.Following failure to respond to physiotherapy both patients underwent arthroscopy which excluded other possible causes for posterolateral knee pain. The decision was made to undertake surgical excision of the fabella in both cases without complication.Both patients were examined 6 month and one year after surgery with the Tegner activity score, the Visual Analogue Scale (VAS), and International Knee Documentation Committee Score (IKDC).
  
  
  CONCLUSIONS
  Consistent posterolateral pain during exercise might indicate the presence of a fabella syndrome. Resecting the fabella can be indicated and is a minor surgical procedure with minimal risk. Despite good results in the literature posterolateral knee pain can persist and prevent return to a high level of sports.
  
  
  METHODS
  IV, case reports and analysis of literature.
authors.forename: Arne
authors.initials: A
authors.lastname: Driessen
authors.forename: Maurice
authors.initials: M
authors.lastname: Balke
authors.forename: Christoph
authors.initials: C
authors.lastname: Offerhaus
authors.forename: William James
authors.initials: WJ
authors.lastname: White
authors.forename: Sven
authors.initials: S
authors.lastname: Shafizadeh
authors.forename: Christoph
authors.initials: C
authors.lastname: Becher
authors.forename: Bertil
authors.initials: B
authors.lastname: Bouillon
authors.affiliation: Department of Traumatology, Clinic for Sports Traumatology, Orthopaedic Surgery and Sports Traumatology, Cologne-Merheim Medical Centre (CMMC), University of Witten/Herdecke (Campus Cologne-Merheim), Ostmerheimerstrasse 200, 51109 Köln, Germany. jhoeher@t-online.de.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Höher
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018771:Arthralgia / Q000209:etiology* / Q000601:surgery; D001182:Arthroscopy; D015444:Exercise; D006801:Humans; D007717:Knee / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology* / Q000601:surgery; D059408:Pain Management; D020427:Peroneal Neuropathies / Q000209:etiology; D011859:Radiography; D020127:Recovery of Function; D012716:Sesamoid Bones / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D013177:Sports; D013577:Syndrome