Measuring finger joint cartilage by ultrasound as a promising alternative to conventional radiograph imaging

Authors

  • Burkhard Möller,

    Corresponding author
    1. University Hospital Berne, Inselspital, Berne, Switzerland
    • Department for Rheumatology, Clinical Immunology and Allergology, University Hospital Berne, Inselspital, Freiburgstrasse, CH 3010-Berne, Switzerland
    Search for more papers by this author
    • Dr. Möller has received speaking fees (less than $10,000 each) from Abbott, Essex, Roche, Sanofi-Aventis, and Wyeth, and has received research grants from Abbott and Sanofi-Aventis.

  • Harald Bonel,

    1. University Hospital Berne, Inselspital, Berne, Switzerland
    Search for more papers by this author
  • Marianne Rotzetter,

    1. University Hospital Berne, Inselspital, Berne, Switzerland
    Search for more papers by this author
  • Peter M. Villiger,

    1. University Hospital Berne, Inselspital, Berne, Switzerland
    Search for more papers by this author
    • Dr. Villiger serves on the advisory boards for Abbott, Essex Chemie, Merck Sharp & Dohme-Chibret, Novartis, Pfizer, Roche Pharma, and Wyeth Pharmaceuticals, Switzerland.

  • Hans-rudolf Ziswiler

    1. University Hospital Berne, Inselspital, Berne, Switzerland
    Search for more papers by this author
    • Dr. Ziswiler has received speaking fees (less than $10,000 each) from Abbott, Pfizer, Merck Sharp & Dohme-Chibret, and Janssen-Cilag, and has received a research grant from Abbott.


Abstract

Objective

To evaluate the reliability and validity of a novel ultrasound (US) imaging method to measure metacarpophalangeal (MCP) and proximal interphalangeal (PIP) finger joint cartilage.

Methods

We examined 48 patients with rheumatoid arthritis (RA), 18 patients with osteoarthritis (OA), 24 patients with unclassified arthritis of the finger joints, and 34 healthy volunteers. The proximal cartilage layer of MCP and PIP joints for fingers 2–5 was bilaterally visualized from a posterior view, with joints in ∼90° flexion. Cartilage thickness was measured with integrated tools on static images. External validity was assessed by measuring radiologic joint space width (JSW) and a numeric joint space narrowing (JSN) score in patients with RA.

Results

Precise measurement was possible for 97.5% of MCP and 94.2% of PIP joints. Intraclass correlation coefficients for bilateral total joint US scores were 0.844 (95% confidence interval [95% CI] 0.648–0.935) for interobserver comparisons and 0.928 (95% CI 0.826–0.971) for intraobserver comparisons (using different US devices). The US score correlated with JSN for both hands (adjusted R2 = 0.513, P < 0.001) and JSW of the same finger joints (adjusted R2 = 0.635, P < 0.001). Reduced cartilage shown by US allowed discrimination of early symptomatic OA versus early RA and healthy joints. In patients with RA, US scores correlated with duration of treatment-resistant, progressive RA.

Conclusion

The US method of direct visualization and quantification of cartilage in MCP and PIP joints is objective, reliable, valid, and can be useful for diagnostic purposes in patients with arthritis.

Ancillary