title: Functional popliteal entrapment syndrome.
abstract: BACKGROUND
  Classic popliteal artery entrapment is caused by the abnormal relationship between the popliteal artery and the medial head of the gastrocnemius, resulting in repetitive arterial compression and trauma. There is, however, a distinct subset of calf claudicants who have an anatomically normal popliteal fossa but can occlude the popliteal artery by repetitive vigorous exercise which involves active plantar flexion with or without extension at the knee joint.
  
  
  METHODS
  Eight patients who led a vigorous athletic lifestyle were evaluated with duplex scan and biplane angiogram after being referred for bilateral calf claudication. They were found to have significant stenosis or occlusion of the popliteal artery with active plantar flexion. All patients had transection of the medial head of the gastrocnemius muscle with release of any vascular bands tethering the popliteal artery.
  
  
  RESULTS
  Seven of the eight patients had complete relief. One patient noticed return of claudication at long distances, but a postoperative angiogram was normal. In all patients postoperative duplex scan showed no stenosis or occlusion of the popliteal vessels with the foot in active plantar flexion and the knee in extension.
  
  
  CONCLUSIONS
  Functional popliteal artery entrapment is becoming a significant cause of disabling claudication in young athletic individuals and needs to be diagnosed accurately for appropriate treatment. This condition is becoming well known with the incorporation of sports in the daily routine of most young people.
authors.affiliation: Department of Vascular Surgery, St Vincent's Hospital, Fitzroy, Victoria, Australia.
authors.forename: A
authors.initials: A
authors.lastname: Deshpande
authors.forename: M
authors.initials: M
authors.lastname: Denton
mesh_terms: D000293:Adolescent; D000328:Adult; D001157:Arterial Occlusive Diseases / Q000175:diagnosis / Q000209:etiology; D003251:Constriction, Pathologic; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D016491:Peripheral Vascular Diseases / Q000175:diagnosis / Q000209:etiology*; D011150:Popliteal Artery