[Neuropathic Pain in Patients Undergoing Primary Total Knee Arthroplasty: Prevalence and Risk Factors].

Abstract

Objective: This study aimed to evaluate the prevalence and risk factors of neuropathic pain (NP) in patients undergoing primary total knee arthroplasty (TKA).

Methods: This prospective observational study included patients aged 18 years or older who were candidates for TKA, conducted between October 2023 and October 2024 at a university hospital. Data were collected from medical records and through the application of a questionnaire assessing socioeconomic variables, comorbidities, prior treatments, and the interview version of the Douleur Neuropathique in 4 questions (DN4i) questionnaire, a validated screening instrument for NP. Paired samples were analyzed using the Wilcoxon, Chi-squared of independence, and Fisher's exact tests, with a significance level set at p  < 0.05.

Results: Of the 68 participants, 20 (29%) tested positive for NP. Among these, most were female (80%, p  = 0.015). Pain intensity was significantly higher in this group, with 90% reporting VAS scores between 8 and 10. There were no significant associations with obesity, diabetes, or the use of pain modulators. Quality of life was more adversely affected in patients with NP, who reported poorer general health status and greater limitations in physical and social activities.

Conclusion: There is a high prevalence of NP among patients undergoing TKA, particularly in females, and is associated with worse quality of life and greater pain intensity. Systematic screening using the DN4i questionnaire may improve diagnosis and support the development of individualized therapeutic strategies.