Identifying discriminant factors between phantom limb pain, residual limb pain, and both in people with lower limb amputations: a cross-sectional study.

Postamputation pain is a common condition in patients with lower limb amputation (LLA), which compromises amputees' rehabilitation, use of the prosthesis, and quality of life. The aim of our study was to investigate the prevalence of phantom limb pain (PLP), residual limb pain (RLP), or both types of pain among individuals with LLA, and to identify the factors associated with the presence of one type of pain versus the other. Patients who underwent amputation for traumatic or vascular reasons and who reported on RLP or PLP were analyzed and divided into three groups: PLP, RLP, or a group of subjects that presented both pains. We searched for factors that affect the occurrence of limb pain using univariate analyses, followed by multinomial logistic regression. Among the 282 participants with transtibial and transfemoral amputations, 192 participants (150 male and 42 female) presented PLP, RLP, or both types of pain, while 90 participants declared to perceive no pain. The estimated prevalence of any type of pain after transfemoral and transtibial amputation was therefore 68% (27% PLP, 10% RLP, and 31% both). Among the studied characteristics, only amputation level was associated with the type of pain ( P  = 0.001). Multinomial logistic regression identified transfemoral amputation as the only statistically significant predictor for PLP (odds ratio = 2.8; P  = 0.002). Hence, it was estimated that individuals with transfemoral amputation have nearly three times higher odds of experiencing PLP compared with those with transtibial amputation.