Spasticity and preservation of skeletal muscle mass in people with spinal cord injury

Abstract

Study design Cross-sectional Objective To investigate the association between skeletal muscle mass and spasticity in people with spinal cord injury (SCI). Setting Tertiary level hospital in Seoul, Korea Methods Spasticity was evaluated in 69 participants with SCI using the spasticity sum score (SSS), Penn Spasm Frequency Scale (PSFS), and Spinal Cord Assessment Tool for Spastic Reflexes (SCATS). Skeletal muscle mass was measured using a dual-energy X-ray absorptiometry scanner, and skeletal muscle index was calculated by dividing skeletal muscle mass by height squared. Laboratory parameters including hemoglobin, albumin, creatinine, fasting glucose, and cholesterol were measured. Spearman's correlation analysis was performed to assess the association between the skeletal muscle mass and spasticity scales. Multiple linear regression analysis was used to present the independent association between them. Results The participants' mean age was 41.8 years; 54 (78.3%) were male, and 46 (66.7%) were tetraplegic. Skeletal muscle index of lower extremities was significantly correlated with all spasticity scales. Spearman's correlation coefficients were 0.468, 0.467, 0.555, 0.506, and 0.474 for SSS, PSFS, SCATS clonus, SCATS flexor, and SCATS extensor with pvalues < 0.001, respectively. After adjustment for age, sex, level of injury, body mass index, and serum creatinine, all spasticity scales were significantly associated with skeletal muscle index of lower extremities in multiple regression analysis. Standardized coefficients were 0.228, 0.274, 0.294, 0.210, and 0.227 for SSS, PSFS, SCATS clonus, SCATS flexor, and SCATS extensor. Conclusions Spasticity was significantly correlated with the skeletal muscle mass even after adjusting for possible confounders. Spasticity may need to be considered as an influencing factor in interventions such as electrical stimulation to preserve skeletal muscle mass.

Ultrasound Imaging as a Diagnostic Tool to Assess the Functional Status of Muscles after a Spinal Cord Injury

“…Muscle shortening is also thought to be a factor that contributes to muscle atrophy (Baker and Matsumoto 1988;Pierotti et al 1991), hence the presence of contractures could also explain differences in the amount of muscle atrophy. In contrast, it has been suggested that muscle spasticity may actually reduce the effects of disuse atrophy by maintaining muscle contractions (Cha et al 2019). There are therefore several factors contributing to the amount of muscle atrophy besides the amount of torque the muscle is able to produce.…”

Spinal Cord Injury as a Model of Bone-Muscle Interactions: Therapeutic Implications From in vitro and in vivo Studies

“…Epidural electrical stimulation (ESS) is a promising technique for improving motor recovery in chronic patients with SCI (69,70). Preliminary results showed that the application of ESS improving both motor control and muscle mass in the lower extremity of patients with severe paralysis or plegia (Figure 1).…”

“…This mechanism is different from that obtained by FES since muscle contraction is mainly indirect. Interestingly, spasticity, which is another indirect, reflex activity in patients with SCI, is associated with partially preserved muscle mass (70).…”

The effects of spasticity on glucose metabolism and soft tissue body composition in patients with spinal cord injury

“…Researchers have shown that spasticity can preserve the muscle mass through muscle contraction in patients with SCI. [ 6 , 7 ] A few studies have proposed that spasticity may affect glucose metabolism positively, as it maintains fat-free mass (FFM) and prevents muscle atrophy in patients with only motor complete SCI. [ 8 - 10 ] In the present study, we aimed to investigate the impact of spasticity on glucose metabolism and FFM in both patients with motor complete SCI and patients with motor incomplete SCI.…”