Article Text

other Versions

PDF
Extended report
Ultrasound for diagnosis of carpal tunnel syndrome: comparison of different methods to determine median nerve volume and value of power Doppler sonography
  1. Christian Dejaco1,
  2. Martin Stradner1,
  3. Dorothea Zauner1,
  4. Werner Seel2,
  5. Nicole Elisabeth Simmet2,
  6. Alexander Klammer1,
  7. Petra Heitzer2,
  8. Kerstin Brickmann1,
  9. Judith Gretler1,
  10. Florentine C Fürst-Moazedi1,
  11. Rene Thonhofer1,3,
  12. Rusmir Husic1,
  13. Josef Hermann1,
  14. Winfried B Graninger1,
  15. Stefan Quasthoff2,4
  1. 1Department of Rheumatology and Immunology, Medical University Graz, Graz, Austria
  2. 2Department of Neurology, Medical University Graz, Graz, Austria
  3. 3Department of Internal Medicine, General hospital Muerzzuschlag, Muerzzuschlag, Austria
  4. 4Department of Neurology, General hospital of the Barmherzige Brüder Eggenberg, Graz, Austria
  1. Correspondence to Dr Christian Dejaco, Department of Rheumatology and Immunology, Medical University Graz, Auenbruggerplatz 15, Graz A-8036, Austria; christian.dejaco{at}gmx.net

Abstract

Objective To compare ultrasound measurement of median nerve cross-sectional area (CSA) at different anatomical landmarks and to assess the value of power Doppler signals within the median nerve for diagnosis of carpal tunnel syndrome (CTS).

Methods A prospective study of 135 consecutive patients with suspected CTS undergoing two visits within 3 months. A final diagnosis of CTS was established by clinical and electrophysiological findings. CSA was sonographically measured at five different levels at forearm and wrist; and CSA wrist to forearm ratios or differences were calculated. Intraneural power Doppler signals were semiquantitatively graded. Diagnostic values of different ultrasound methods were compared by receiver operating characteristic curves using SPSS.

Results CTS was diagnosed in 111 (45.5%) wrists; 84 (34.4%) had no CTS and 49 (20.1%) were possible CTS cases. Diagnostic values were comparable for all sonographic methods to determine median nerve swelling, with area under the curves ranging from 0.75 to 0.85. Thresholds of 9.8 and 13.8 mm2 for the largest CSA of the median nerve yielded a sensitivity of 92% and a specificity of 92%. A power Doppler score of 2 or greater had a specificity of 90% for the diagnosis of CTS. Sonographic median nerve volumetry revealed a good reliability with an intraclass correlation coefficient of 0.90 (95% CI 0.79 to 0.95).

Conclusions Sonographic assessment of median nerve swelling and vascularity allows for a reliable diagnosis of CTS. Determination of CSA at its maximal shape offers an easily reproducible tool for CTS classification in daily clinical practice.

  • Ultrasonography
  • Orthopedic Surgery
  • Qualitative research

Statistics from Altmetric.com

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.