Prevalence and clinical predictors of spasticity after intracerebral hemorrhage.

BACKGROUND: Spasticity is a common complication of intracerebral hemorrhage (ICH). However, no consensus exists on the relation between spasticity and initial clinical findings after ICH. METHODS: This retrospective study enrolled adult patients with a history of ICH between January 2012 and October 2020. The modified Ashworth scale was used to assess spasticity. A trained image analyst traced all ICH lesions. Multivariable logistic regression was used to examine the association between ICH lesion sites and spasticity. RESULTS: We finally analyzed 304 patients (mean age 54.86 ± 12.93 years; 72.04% men). The incidence of spasticity in patients with ICH was 30.92%. Higher National Institutes of Health stroke scale (NIHSS) scores were associated with an increased predicted probability for spasticity (odds ratio, OR = 1.153 [95% confidence interval, CI 1.093-1.216], p < .001). Logistic regression analysis revealed that lower age, higher NIHSS scores, and drinking were associated with an increased risk of moderate-to-severe spasticity (OR = 0.965 [95% CI 0.939-0.992], p = .013; OR = 1.068 [95% CI 1.008-1.130], p = .025; OR = 4.809 [95% CI 1.671-13.840], p = .004, respectively). However, smoking and ICH in the thalamus were associated with a reduced risk of moderate-to-severe spasticity (OR = 0.200 [95% CI 0.071-0.563], p = .002; OR = 0.405 [95% CI 0.140-1.174], p = .046, respectively) compared with ICH in the basal ganglia. CONCLUSIONS: Our results suggest that ICH lesion locations are at least partly associated with post-stroke spasticity rather than the latter simply being a physiological reaction to ICH itself. The predictors for spasticity after ICH were age, NIHSS scores, past medical history, and ICH lesion sites.

Histological, enzymohistochemical and biomechanical observation of skeletal muscle injury in rabbits.

OBJECTIVE: To explore the pathophysiological and biomechanical features of skeletal muscular injury for providing a rational basis for its treatment, prevention and rehabilitation. METHODS: In 70 adult rabbits, the left tibialis anterior (TA) muscle was stretched to injury, while the right TA muscle served as control. Histological, enzymohistochemical and biomechanical changes were observed on days 0, 1, 2, 3, and 7 after injury. Cytochrome oxidase (CCO), acid phosphatase (ACP), ATPase, succinate dehydrogenase (SDH), malate dehydrogenase (MDH), NADH-diaphorase (NADHD), glutamatedehydrogenase (GDH), alpha-glycerophosphate dehydrogenase (alpha-GPD) and lactate dehydrogenase (LDH) were measured. The examined biomechanical parameters included maximal contractile force, ultimate load, length, energy absorption, tangent stiffness, and rupture site. RESULTS: Partial or complete rupture of TA muscle occurred near the muscle-tendon junction. There was an intense inflammatory reaction on day 1 and 2 after injury. Endomysium fibrosis and myotube formation were observed on day 3, and developed further on day 7. The activity of cell oxidases (CCO, ATPase, MDH, alpha-GPD, SDH, NADHD and GDH) showed a significant drop from day 0 to 2, and resumed with different levels on day 3. The increment of enzymatic activities continued on day 7 and the levels of NADHD and alpha-GPD reached to the levels of control muscle. Maximal contractile force was 70.17%+/-3.82% of controls immediately after injury, 54.82%+/-3.09% at 1 day, 66.41%+/-4.36% at 2 days, 78.39%+/-4.90% at 3 days and 93.64%+/-5.02% at 7 days. Ultimate load was 85.78%+/-7.54% of controls at the moment of injury, 61.44%+/-5.91% at 1 day, 49.17%+/-4.26% at 2 days, 64.43%+/-5.02% at 3 days, and 76.71%+/-6.46% at 7 days. CONCLUSIONS: Endomysium fibrosis and scar formation at the injured site are responsible for frequent recurrence of skeletal muscle injury. Recovery of tensile load slower than that of maximal contractile force may be another cause. Whether the injured muscle returns to normal exercise is mainly determined by the tensility on which the muscle-tendon can bear rather than the maximal contractile force.