Spasticity and pain in patients with disorders of consciousness

Abstract

Spasticity is a common complication after a severe brain injury that hinders the rehabilitative process, reduces the patients’ quality of life and is frequently responsible of pain (Thibaut et al., 2015). Here, we investigate in a population of patients with disorders of consciousness the correlation between spasticity and pain during mobilization to better characterize the spastic profiles that are more prone to induce pain. In this cross-sectional study 73 patients with chronic (>3 months post insult) disorders of consciousness were included [27 women; mean age: 40 ± 13 y; 42 with traumatic etiology; 50 in minimally conscious state (MCS) and 23 in unresponsive wakefulness syndrome (UWS)]. We evaluated the pain with the Nociceptive Coma Scale-Revised (NCS-R) and the spasticity with the Modified Ashworth Scale (MAS). Out of 73 patients, 70 demonstrated signs of spasticity (96%; MAS ≥ 1), including 52 who showed severe spasticity (71%; MAS ≥ 4 at least in one joint; 35 in MCS and 17 in UWS). Moreover, 13 patients in MCS (26%) and 5 in UWS (22%) showed severe pain during mobilization (NCS-R ≥ 4 at least in one joint). Moreover, we found a strong correlation with the Spearman's rank correlation indicator between pain during mobilization and the spasticity of the wrist's and fingers’ flexors and hip's adductors (respectively ρ=0.254, P = 0.03; ρ=0.269, P = 0.02; ρ=0.277, P = 0.02), while the correlation was weaker for biceps, knee's and ankle's flexors (respectively ρ=0.195, P = 0.1; ρ=0.176, P = 0.14; ρ=0.115, P = 0.36). We confirm the high prevalence of spasticity and pain in patients with disorders of consciousness and the correlation between the degrees of spasticity and pain scores. We found that the peripheral joints of the upper limbs and the hip adductors are more prone to induce pain. These data highlight the need to prevent the onset of spasticity and the importance of the treatment of pain in patients with disorders of consciousness.