Association Between the Microbiological Characteristics of Postoperative Stump Wound Infections and Neuropathic Pain After Limb Amputation: A Cross-Sectional Observational Study.

BACKGROUND: Chronic stump pain after limb amputation is a multifactorial condition that has become increasingly relevant in the context of modern trauma and armed conflicts. Although microbiological, neurological, and psychological factors have each been implicated in post-amputation pain, their combined relationship remains insufficiently understood. AIM: To investigate the associations between pain characteristics, wound microbiology, and psychological factors in patients with postoperative stump wound infections following limb amputation. METHODS: This cross-sectional observational study included 73 patients with stump wounds persisting for more than six weeks after limb amputation. Pain intensity was assessed using the Numerical Rating Scale (NRS), and neuropathic pain characteristics were evaluated using the Douleur Neuropathique 4 (DN4) questionnaire. Psychological status was assessed using the Patient Health Questionnaire-9 (PHQ-9) and the PTSD Screening Scale-5. Microbiological analysis included pathogen identification and bacterial load (CFU/mL), with clinically significant bacterial growth defined as >105 CFU/mL. Patients were stratified according to the presence of clinically significant bacterial growth. Associations between variables were analyzed using Spearman's rank correlation, the Mann-Whitney U-test, and multiple linear regression. RESULTS: No statistically significant associations were identified between microbiological parameters and neuropathic pain scores. The correlation between NRS and DN4 scores was weak and non-significant (r = 0.18, p = 0.117). In contrast, higher PHQ-9 scores were independently associated with higher DN4 scores (β = 0.255, p = 0.027). The regression models demonstrated low explanatory power (R2 = 0.089-0.137), suggesting that neuropathic pain after amputation is influenced by multiple factors beyond those evaluated in the present study. CONCLUSION: In this study, no statistically significant association was identified between microbiological characteristics of stump wounds and neuropathic pain. Depressive symptoms were significantly associated with neuropathic pain severity, highlighting the importance of incorporating psychological assessment into the multidisciplinary management of patients after limb amputation. Larger prospective studies are warranted to further clarify these relationships.