Among patients with osteoarthritis of the knee, women experienced greater sensitivity to various pain modalities -such as lower tolerance to heat, cold, and pressure - and greater widespread pain than men.

The findings may be helpful for clinicians as they decide which treatments are best for different patients. Additional studies on the mechanisms involved the sex differences observed this study may also help researchers develop new treatment strategies for patients.

"Many questions still remain as to why women with knee osteoarthritis are more sensitive to painful stimuli than are men. While therapeutic approaches to control pain are only beginning to take these sex differences into account, there is still quite a bit of research yet to be done to help reduce this gender gap and improve clinical therapies for men and women alike," said Dr. Emily Bartley, lead author of the Arthritis Care & Research study.

Research: Enhanced pain sensitivity among individuals with symptomatic knee osteoarthritis: Potential sex differences in central sensitization, Emily J. Bartley PhD, Christopher D. King PhD, Kimberly T. Sibille PhD, Yenisel Cruz-Almeida MSPH, PhD, Joseph L. Riley III PhD, Toni L. Glover PhD, GNP-BC, Burel R. Goodin PhD, Adriana S. Sotolongo MPH, Matthew S. Herbert PhD, Hailey W. Bulls BS, Roland Staud MD, Barri J. Fessler MSPH, MD, David T. Redden PhD, Laurence A. Bradley PhD and Roger B. Fillingim PhD, Arthritis Care & Research, doi: 10.1002/acr.22712, published online 5 October 2015.