Skeletal Radiology

, Volume 33, Issue 12, pp 719–724 | Cite as

Accuracy of plain films, and the effect of experience, in the assessment of ankle effusions

  • Michael Karchevsky
  • Mark E. SchweitzerEmail author
Scientific Article



To investigate the accuracy of plain radiographs, and the effect of observer experience, in the assessment of ankle effusions compared with an MRI gold standard.

Design and patients

Anteroposterior (AP) and lateral radiographs of the ankle of 39 patients were evaluated by four observers, ranging from first-year radiology resident to an attending musculoskeletal radiologist. Observers independently graded the lateral films from 0 to5 at one sitting, and the AP films at a second sitting. All patients had an MRI scan performed within 48 h of the ankle radiographs, on which distention of the anterior recess was used as the gold standard for an effusion.


Lateral radiographs had variable sensitivity (range 17―63%), but specificity (81–94%) was usually high. AP radiographs similarly had variable sensitivity (15–55%), but their specificity (63–75%) was surprisingly good. Overall, sensitivity and specificity were inversely proportional and more related to individual variability than experience (observer 1, 53% and 81%; observer 2, 17% and 94%; observer 3, 63% and 88%; observer 4, 21% and 94%); however, individual sensitivity and specificity were consistent between AP and lateral radiographs (observer 1, 53% and 81%, 50% and 65%; observer 2, 17% and 94%, 15% and 75%), observer 3, 63% and 88%, 55% and 63%; observer 4, 21% and 94%, 25% and 70%). Positive predictive value was reasonably good for lateral radiographs (range 75―86%); however, it was fairly low for AP radiographs (38–61%). Negative predictive value was low for both lateral (50–67%) and AP (47–58%) radiographs. Accuracy was low for both AP (45–59%) and lateral (53–74%) radiographs. As expected, individual accuracy was consistently higher for lateral radiographs than for AP radiographs (observer 1, 65% and 58%; observer 2, 53% and 45%; observer 3, 74% and 59%; observer 4, 54% and 48%).


For the diagnosis of ankle effusions the overall accuracy of radiographs was surprisingly low. Quite surprisingly, the diagnosis of effusions on AP radiographs was not much poorer than on lateral films. Results, however, varied little with experience and training.


Ankle Articular effusion Radiography MRI 


  1. 1.
    Resnick D, Niwayama G. Articular anatomy and histology. In: Resnick D, ed. Bone and joint imaging. Philadelphia: Saunders, 1989:29–35.Google Scholar
  2. 2.
    Ropes MW, Rossmeisi EC, Bauer W. The origin and nature of normal human synovial fluid. J Clin Invest 1940; 19:795–799.Google Scholar
  3. 3.
    Resnick D, Georgen TG, Niwayama G. Traumatic, iatrogenic and neurologic diseases. In: Resnick D, Niwayama G, eds. Diagnosis of bone and joint disorders, vol 5. Philadelphia: Saunders, 1988:826–827.Google Scholar
  4. 4.
    Hall FM. Radiographic diagnosis and accuracy in knee joint effusions. Radiology 1975; 115:49–54.PubMedGoogle Scholar
  5. 5.
    Hayden C, Swischuk L. Paraarticular soft-tissue changes in infections and trauma of the lower extremity in children. AJR Am J Roentgenol 1980; 134:307–311.PubMedGoogle Scholar
  6. 6.
    Schweitzer M, van Leersum M, Ehrlich S, Wapner K. Fluid in normal and abnormal ankle joints: amount and distribution as seen on MR images. AJR Am J Roentgenol 1994; 162:111–114.PubMedGoogle Scholar
  7. 7.
    Nazarian L, Rawool N, Martin C, Schweitzer M. Synovial fluid in the hindfoot and ankle: detection of amount and distribution with US. Radiology 1995; 197:275–278.PubMedGoogle Scholar
  8. 8.
    Thermann H, Hoffmann R, Zwipp H, Tscherne H. The use of ultrasonography in the foot and ankle. Foot Ankle 1992; 13:386–390.PubMedGoogle Scholar
  9. 9.
    Simkin PA. Synovial physiology. In: McCarty DJ, ed. Arthritis and allied conditions, 12th edn. Philadelphia: Lea & Febiger, 1989:209–211.Google Scholar
  10. 10.
    Clark TWI, Janzen DL, Logan PM, HO K, Connell DG. Improving the detection of radiographically occult ankle fractures: positive predictive value of an ankle joint effusion. Clin Radiol 1996; 51:632–636.PubMedGoogle Scholar
  11. 11.
    Zawin J, Hoffer F, Rand F, Teele R. Joint effusion in children with an irritable hip: US diagnosis and aspiration. Radiology 1993; 187:459–463.PubMedGoogle Scholar
  12. 12.
    Wunderbaldinger P, Bremer C, Schellenberger E, Cejna M, Turetschek K, Kainberger F. Imaging features of iliopsoas bursitis. Eur Radiol 2002; 12:409–415.CrossRefPubMedGoogle Scholar
  13. 13.
    Jacobson J, Andresen R, Jaovisidha S, et al. Detection of ankle effusions: comparison study in cadavers using radiography, sonography, and MR imaging. AJR Am J Roentgenol 1998; 170:1231–1238.PubMedGoogle Scholar
  14. 14.
    Arroll B, Schechter M, Sheps S. The assessment of diagnostic tests: a comparison of medical literature in 1982 and 1985. J Gen Intern Med 1988; 3:443–447.PubMedGoogle Scholar
  15. 15.
    Sheps S, Schechter M. The assessment of diagnostic tests. JAMA 1984; 252:2418–2422.CrossRefPubMedGoogle Scholar
  16. 16.
    Baier M, Calonge N, Cutter G, et al. Validity of self-reported colorectal cancer screening behavior. Cancer Epidemiol Biomarkers Prev 2000; 9:229–232.PubMedGoogle Scholar
  17. 17.
    Singh V, Sehgal A, Parashari A, Sodhani P, Satyanarayana L. Early detection of cervical cancer through acetic acid application—an aided visual inspection. Singapore Med J 2001; 42:351–354.PubMedGoogle Scholar
  18. 18.
    Sienko D, Hahn R, Mills E, et al. Mammography use and outcomes in a community: the Greater Lansing Area Mammography Study. Cancer 1993; 71:1801–1809.PubMedGoogle Scholar
  19. 19.
    Englestad B, Friedman E, Murphy W. Diagnosis of joint effusion on lateral and axial projections of the knee. Invest Radiol 1981; 16:188–192.PubMedGoogle Scholar
  20. 20.
    Rehan VK, Seshia MM, Johnston B, Reed M, Wilmot D, Cook V. Observer variability in interpretation of abdominal radiographs of infants with suspected necrotizing enterocolitis. Clin Pediatr 1999; 38:637–643.Google Scholar
  21. 21.
    Timmerman D, Schwarzler P, Collins WP, et al. Subjective assessment of adnexal masses with the use of ultrasonography: an analysis of interobserver variability and experience. Ultrasound Obstet Gynecol 1999; 13:11–16.CrossRefPubMedGoogle Scholar
  22. 22.
    Robertson PL, Schweitzer ME, Mitchell DG, et al. Rotator cuff disorders: interobserver and intraobserver variation in diagnosis with MR imaging. Radiology 1995; 194:831–835.Google Scholar

Copyright information

© ISS 2004

Authors and Affiliations

  1. 1.Department of RadiologyThomas Jefferson University HospitalPhiladelphiaUSA
  2. 2.Department of RadiologyHospital for Joint DiseasesNew YorkUSA

Personalised recommendations