title: Which knee and probe position determines the final diagnosis of knee inflammation by ultrasound? Results from a European multicenter study.
abstract: OBJECTIVE
  To investigate which knee and probe position best identifies knee inflammation and to determine a cut-off level for abnormal synovial effusion.
  
  
  METHODS
  18 experienced sonographers (all rheumatologists) performed ultrasound examinations of the knee joint in patients with knee symptoms and in healthy controls. Each sonographer performed longitudinal suprapatellar ultrasound scans using 9 different configurations at each knee: Midline, parapatallar lateral and parapatellar medial from midline in neutral position (0°) with and without quadriceps muscle contraction and in 30° flexion of the knee. The presence of synovial effusion (SE), the effusion measured in millimeters and the presence of synovial hypertrophy (SH) was noted.
  
  
  RESULTS
  A total of 298 knees of 149 subjects (129 patients and 20 controls) were examined. The detection of SH is more sensitive and specific than the detection of SE, independently of the knee and probe position, for the final diagnosis of abnormality. The detection of both synovial hypertrophy and effusion in the knee in neutral position (0°) with quadriceps contraction and with the probe in the midline position, are the best independent predictors for knee abnormalities. Knee effusion > 3.2 mm measured with the probe in the lateral aspect of the knee is the best diagnostic characteristics for predicting pathological SE.
  
  
  CONCLUSIONS
  The best combination for detecting SH and SE is obtained by placing the probe in the midline position with the knee in 0° with quadriceps contraction. A cut-off value for pathological effusion may be obtained in the lateral aspect of the knee.
authors.affiliation: Department of Rheumatology, University of Copenhagen, Hospitals at Glostrup, Copenhagen, Denmark.
authors.forename: L
authors.initials: L
authors.lastname: Terslev
authors.affiliation: Paris Ouest-Versailles-Saint Quentin en Yvelines University; EA 2506, Rheumatology Department Ambroise-Paré Hospital, APHP, Boulogne-Billancourt, France.
authors.forename: M A
authors.initials: MA
authors.lastname: D'Agostino
authors.affiliation: Paris Ouest-Versailles-Saint Quentin en Yvelines University; EA 2506, Rheumatology Department Ambroise-Paré Hospital, APHP, Boulogne-Billancourt, France.
authors.forename: M
authors.initials: M
authors.lastname: Brossard
authors.affiliation: Paris Ouest-Versailles-Saint Quentin en Yvelines University; EA 2506, Public Health Department Ambroise-Paré-Hospital, APHP, Boulogne-Billancourt, France.
authors.forename: P
authors.initials: P
authors.lastname: Aegerter
authors.affiliation: National Institute of Rheumatology and Physiotherapy, 3rd Department of Pediatric and General Rheumatology Budapese, Hungary.
authors.forename: P
authors.initials: P
authors.lastname: Balint
authors.affiliation: Department of Rheumatology and Clinical Immunology, Charité, Berlin, Gremany.
authors.forename: M
authors.initials: M
authors.lastname: Backhaus
authors.affiliation: MC Groep hospitals, Lelystad, Netherlands.
authors.forename: G A
authors.initials: GA
authors.lastname: Bruyn
authors.affiliation: Department of Rheumatology, University of Nancy, Le Brabois Hospital, Nancy, France.
authors.forename: I
authors.initials: I
authors.lastname: Chary-Valckenare
authors.affiliation: Cattedra di Reumatologia, Università Politecnica delle Marche, Ancona, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Filippucci
authors.affiliation: LIMM Section of Musculoskeletal Disease, University of Leeds, Chapel Allerton Hospital, Leeds, England.
authors.forename: J
authors.initials: J
authors.lastname: Freeston
authors.affiliation: Department of Rheumatology, la Pitié-Salpêtrière Hospital, APHP, Paris, France.
authors.forename: F
authors.initials: F
authors.lastname: Gandjbakhch
authors.affiliation: Rheumatology Unit, Clinica e Terapia Medica Department, Sapienza Università di Roma, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Iagnocco
authors.affiliation: Rheumatology Department, La Cavale Blanche Brest Teaching Hospital, Brest, France.
authors.forename: S
authors.initials: S
authors.lastname: Jousse-Joulin
authors.affiliation: National Institute of Rheumatology and Physiotherapy, 3rd Department of Pediatric and General Rheumatology Budapese, Hungary.
authors.forename: P
authors.initials: P
authors.lastname: Mandl
authors.affiliation: Instituto Poal de Reumatologia, Barcelona, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Möller
authors.affiliation: Rheumatology Department, Hospital Severo Ochoa, Madrid, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Naredo
authors.affiliation: Department of Rheumatology, University of Copenhagen Hospital at Koege, Koege, Denmark.
authors.forename: M
authors.initials: M
authors.lastname: Szkudlarek
authors.affiliation: LIMM Section of Musculoskeletal Disease, University of Leeds, Chapel Allerton Hospital, Leeds, England.
authors.forename: R J
authors.initials: RJ
authors.lastname: Wakefield
authors.affiliation: LIMM Section of Musculoskeletal Disease, University of Leeds, Chapel Allerton Hospital, Leeds, England.
authors.forename: A
authors.initials: A
authors.lastname: Zayat
authors.affiliation: Immanuel Krankenhaus Berlin, Medical Centre for Rheumatology Berlin-Buch, Berlin, Germany.
authors.forename: W A
authors.initials: WA
authors.lastname: Schmidt
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001168:Arthritis / Q000000981:diagnostic imaging*; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D006984:Hypertrophy; D007719:Knee Joint / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging*; D010329:Patella / Q000000981:diagnostic imaging; D056888:Patient Positioning; D016059:Range of Motion, Articular / Q000502:physiology; D012016:Reference Values; D012680:Sensitivity and Specificity; D013582:Synovial Fluid / Q000000981:diagnostic imaging*; D013583:Synovial Membrane / Q000000981:diagnostic imaging / Q000473:pathology; D014463:Ultrasonography; D055815:Young Adult