Osteoarthritis may not be a one-way-road of cartilage loss – comparison of spatial patterns of cartilage change between osteoarthritic and healthy knees

Buck, R.J.; Wyman, B.T.; Hellio Le Graverand, M.-P.; Hudelmaier, M.; Wirth, W.; Eckstein, F.; for the A 9001140 investigators,

doi:10.1016/j.joca.2009.11.009

« Previous Next »Osteoarthritis and Cartilage
Volume 18, Issue 3 , Pages 329-335, March 2010

Osteoarthritis may not be a one-way-road of cartilage loss – comparison of spatial patterns of cartilage change between osteoarthritic and healthy knees

R.J. Buck
- Pfizer Global Research and Development, New London, CT, USA
- Address correspondence and reprint requests to: Robert J. Buck, StatAnswers Consulting LLC, 5392 Renaissance Ave, San Diego, CA 92122, United States. Tel/Fax: 1-858-412-6968.
B.T. Wyman
- Pfizer Global Research and Development, New London, CT, USA
M.-P. Hellio Le Graverand
- Pfizer Global Research and Development, New London, CT, USA
M. Hudelmaier
- Institute of Anatomy & Musculoskeletal Research, Paracelsus Medical University (PMU), Salzburg, Austria
- Chondrometrics GmbH, Ainring, Germany
W. Wirth
- Chondrometrics GmbH, Ainring, Germany
F. Eckstein
- Institute of Anatomy & Musculoskeletal Research, Paracelsus Medical University (PMU), Salzburg, Austria
- Chondrometrics GmbH, Ainring, Germany
for the A 9001140 investigators

Received 29 April 2009; accepted 18 November 2009. published online 14 December 2009.

Summary

Objective

To explore whether longitudinal change in cartilage thickness in femorotibial subregions of knees with radiographic osteoarthritis (ROA) differs from that in healthy knees.

Methods

3T coronal magnetic resonance (MR) images were acquired in 152 women at seven clinical centers at baseline (BL) and 24 months. Knees from 75 women with signs of ROA in either anterior–posterior or Lyon schuss radiographs were compared with those from 77 asymptomatic healthy controls without ROA to identify knees showing greater change in cartilage thickness than expected based on observations in healthy knees. The femorotibial cartilage thickness was determined in BL and follow-up MR images across five tibial and three femoral subregions in the medial/lateral compartment, respectively.

Results

A substantial portion of knees with ROA were classified as having longitudinal cartilage thinning (28%) or thickening (20%) in at least one medial femorotibial subregion based on comparisons to longitudinal changes observed in healthy knees; only 5% showed both subregional thinning and thickening across (different) medial subregions at the same time. Whereas the estimated proportion of Kellgren Lawrence grade (KLG) 3 knees (n=28) with significant medial cartilage thinning (46%) was substantially greater than that with cartilage thickening (18%), the estimated percentages of KLG2 knees (n=30) with significant medial thinning (20%) and thickening (23%) were similar.

Conclusion

This exploratory study indicates that OA may not be a one-way-road of cartilage loss. Subregional analysis suggests that, compared with healthy knees, cartilage changes in ROA may occur in both directions. Medial femorotibial cartilage thickening was observed as frequently as cartilage thinning in KLG2 knees.

Key words: MRI, cartilage thickness, cartilage thinning, cartilage thickening, longitudinal, radiographic OA