Architecture of the Triceps Surae Muscles Complex in Patients with Spastic Hemiplegia: Implication for the Limited Utility of the Silfverskiöld Test

Does ultrasound imaging of the spastic muscle have an additive effect on clinical examination tools in patients with cerebral palsy?: A pilot study

Objective

The Modified Ashworth Scale, the Modified Tardieu Scale, and measuring the passive range of motion is commonly preferred examination tools for spasticity in cerebral palsy (CP). Ultrasonography has become increasingly used to provide relevant insight into spastic muscle morphology and structure recently. It was aimed to reveal associations between the clinical and ultrasonographic parameters of gastrocnemius medialis (GM) and lateralis muscles in this population.

Methods

Thirty-four children with spastic CP aged between 4 and 12 years who did not have botulinum neurotoxin A intervention within 6 months or had no previous history of any orthopedic or neurological surgery were included. The spasticity of GM and lateralis was evaluated firstly by the Modified Ashworth Scale, Modified Tardieu Scale, and ankle passive range of motion. Then, the cross-sectional area (CSA), muscle thickness (MT), qualitative and quantitative echo intensity (EI) values of both muscles were measured from their ultrasonographic images.

Results

The CSA of GM, and qualitative EI of both muscles were found to be mild-to-moderately correlated to all clinical examination tools (p<0.01), whereas the CSA of gastrocnemius lateralis was mildly related to Modified Ashworth Scale (p=0.009). The MT and quantitative EI of both muscles were not associated with any of the clinical tools (p>0.05).

Conclusion

Ultrasonographic measurements of GM and lateralis partially reflect ankle spasticity in children with CP. Ultrasonography can be used as an alternative tool in this patient population where the clinical evaluation can not perform ideally.

Impact of Altered Gastrocnemius Morphometrics and Fascicle Behavior on Walking Patterns in Children With Spastic Cerebral Palsy

Spastic cerebral palsy (SCP) affects neural control, deteriorates muscle morphometrics, and may progressively impair functional walking ability. Upon passive testing, gastrocnemius medialis (GM) muscle bellies or fascicles are typically shorter, thinner, and less extensible. Relationships between muscle and gait parameters might help to understand gait pathology and pathogenesis of spastic muscles. The current aim was to link resting and dynamic GM morphometrics and contractile fascicle behavior (both excursion and velocity) during walking to determinants of gait. We explored the associations between gait variables and ultrasonography of the GM muscle belly captured during rest and during gait in children with SCP [n = 15, gross motor function classification system (GMFCS) levels I and II, age: 7–16 years] and age-matched healthy peers (n = 17). The SCP children’s plantar flexors were 27% weaker. They walked 12% slower with more knee flexion produced 42% less peak ankle push-off power (all p < 0.05) and 7/15 landed on their forefoot. During the stance phase, fascicles in SCP on average operated on 9% shorter length (normalized to rest length) and displayed less and slower fascicle shortening (37 and 30.6%, respectively) during push-off (all p ≤ 0.024). Correlation analyses in SCP patients revealed that (1) longer-resting fascicles and thicker muscle bellies are positively correlated with walking speed and negatively to knee flexion (r = 0.60–0.69, p < 0.0127) but not to better ankle kinematics; (2) reduced muscle strength was associated with the extent of eccentric fascicle excursion (r = −0.57, p = 0.015); and (3) a shorter operating length of the fascicles was correlated with push-off power (r = −0.58, p = 0.013). Only in controls, a correlation (r = 0.61, p = 0.0054) between slower fascicle shortening velocity and push-off power was found. Our results indicate that a thicker gastrocnemius muscle belly and longer gastrocnemius muscle fascicles may be reasonable morphometric properties that should be targeted in interventions for individuals with SCP, since GM muscle atrophy may be related to decreases in walking speed and undesired knee flexion during gait. Furthermore, children with SCP and weaker gastrocnemius muscle may be more susceptible to chronic eccentric muscle overloading. The relationship between shorter operating length of the fascicles and push-off power may further support the idea of a compensation mechanism for the longer sarcomeres found in children with SCP. Nevertheless, more studies are needed to support our explorative findings.

The Interzonal Distribution of the Load on the Plantar Surface of the Foot During Walking in the Patients with Cerebral Palsy as an Objective Criterion of Functional Impairment Severity

Relevance. The main direction of rehabilitation of children with cerebral palsy is the preservation and enhancement of the existing level of support and locomotion, as well as compensation of its impairment through various methods of rehabilitation. For an adequate prescription and reliable assessment of these measures effectiveness, it is necessary to use objective indicators of functional impairment characteristic of cerebral palsy. The purpose of this study was to substantiate objective biomechanical indicators of functional impairment in children with cerebral palsy based on the analysis of the interzonal distribution of the load on the foot during walking, taking into account the level of global motor functions impairment. Materials and Methods. 47 children with cerebral palsy at the GMFCS levels of impairment 1 to 3 were examined. The control group consisted of 14 children without anatomical and functional signs of support and locomotion system impairment. Biomechanical examination was performed on the complex «DiaSled-M-Scan» with matrix plantar pressure meters in the form of insoles. The statistical analysis of the data was carried out by nonparametric methods using the SPSS for Widows software. Results. The analysis of the anatomical and functional impairment of 94 feet of the children with cerebral palsy and 28 feet of the control group revealed differences in the interzonal distribution of the load under the feet in six variables (p from 0.001 to 0.003). The most typical were: an increase in the toe-to-heel load ratio (on average by 80%), an increase in the load on the arch (by 49%), and a decrease in the medio-lateral load ratio on the toe (by 37%). For GMFCS 1 patients, a significant indicator of impairment was an increase in the partial load on the arch, for GMFCS 2 and 3 patients — a decrease in the load on the heel and an increase it under the toe. This leads to an increase in the toe-to-heel load ratio. Conclusion. It is advisable to use the revealed indicators of roll-over-the-foot impairment in the functional diagnosis of the condition and in assessing the effectiveness of rehabilitation of children with cerebral palsy.