Higher levels of total testosterone were found to be associated with reduced pain intensity in the operated knee of patients who underwent total knee replacement (TKR) for severe knee osteoarthritis (OA), according to study results published in Arthritis Care & Research.

The study included 272 participants (53% women) aged ≥60 years who underwent unilateral TKR because of severe knee OA. Serum testosterone levels were measured and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores were assessed in the operated and contralateral knee 6 to 8 weeks after surgery. A total of 56% of participants had radiographic knee OA with a Kellgren-Lawrence grade ≥2 in the nonoperated knee. The researchers performed cross-sectional analyses by gender and body mass index subgroups and used multivariable regression that adjusted for age, physical activity, and body mass index.

Higher serum testosterone levels in the operated knee were associated with lower WOMAC pain scores in both men and women (P =.02 for both) and with decreased WOMAC disability scores in women and obese men (P =.02 for both). In the nonoperated knee, serum testosterone levels were not associated with WOMAC pain score but were associated with less disability in women (P =.02).

Study limitations include its cross-sectional design, and that postsurgery analgesic regimens may have influenced the association between serum testosterone levels and WOMAC pain and disability.

“Additional studies with a prospective design are needed to further explore and clarify the role of higher physiological [testosterone] levels in patients with symptomatic knee OA,” noted the researchers.

Reference

Freystaetter G, Fischer K, Orav EJ, et al. Total serum testosterone and WOMAC pain and function among older men and women with severe knee OA [published online September 26, 2019]. Arthritis Care Res. doi:10.1002/acr.24074