title: Sonography for hip joint effusion in adults with hip pain.
abstract: OBJECTIVE
  To study the prevalence of ultrasonic hip joint effusion and its relation with clinical, radiological and laboratory (ESR) findings in adults with hip pain.
  
  
  METHODS
  Patients (n = 224) aged 50 years or older with hip pain, referred by the general practitioner for radiological investigation, underwent a standardised examination. The distance between the ventral capsule and the femoral neck, an increase in which represents joint effusion, was measured sonographically. Joint effusion was defined in three different ways: "effusion" according to Koski's definition, "major effusion", and "asymmetrical effusion" based on only individual side differences.
  
  
  RESULTS
  "Effusion" was present in 80 (38%), "major effusion" in 20 (9%), and "asymmetrical effusion" in 47 (22%) patients. Pain in the groin or medial thigh, pain aggravated by lying on the side, decreased extension/internal rotation/abduction/flexion, painful external rotation, and pain on palpation in the groin showed a significant relation (adjusted for age and radiological osteoarthritis of the hip) with ultrasonic hip joint effusion. "Major effusion" showed a significant relation with an increased ESR. When patients with bilateral pain and increased ESR were excluded, a side difference in the range of motion of extension of the hip was shown to be a good predictor for "asymmetrical effusion" (positive predictive value: 71%, negative predictive value: 80%).
  
  
  CONCLUSIONS
  This study showed a relatively high prevalence of ultrasonic joint effusion in adults with hip pain in general practice. Furthermore the results indicate a relation between joint effusion and clinical signs.
authors.affiliation: Department of General Practice, Erasmus University, Rotterdam, The Netherlands.
authors.forename: S M
authors.initials: SM
authors.lastname: Bierma-Zeinstra
authors.forename: A M
authors.initials: AM
authors.lastname: Bohnen
authors.forename: J A
authors.initials: JA
authors.lastname: Verhaar
authors.forename: A
authors.initials: A
authors.lastname: Prins
authors.forename: A Z
authors.initials: AZ
authors.lastname: Ginai-Karamat
authors.forename: J S
authors.initials: JS
authors.lastname: Laméris
mesh_terms: D000368:Aged; D005122:Exudates and Transudates / Q000000981:diagnostic imaging*; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007592:Joint Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging; D010146:Pain / Q000000981:diagnostic imaging; D010173:Palpation; D016059:Range of Motion, Articular; D014463:Ultrasonography