Specificity of manual testing of the gluteal muscle strength in preschool children: a single-center cross-sectional study

Background
Manual Muscle Testing (MMT) is a procedure used to assess the strength and function of individual muscles and muscle groups based on effective movement in relation to the forces of gravity and manual resistance. The introduction of MMT into the diagnosis of developmental age is a complex issue due to the challenge of obtaining cooperation from the child undergoing the test. While some authors have attempted to implement MMT in children, clear recommendations regarding the lower age limit have not been firmly established.

Aims
This study aimed to establish the criteria for conducting MMT in healthy preschool children, identify standard protocols for test administration, and assess the potential influence of biometric parameters (such as age, gender, height, and weight) on test performance.

Material and methods
A group of 111 children underwent observation and was divided into two age groups. Group I comprised children aged from the completion of the 3rd year to the beginning of the 5th year (n=47; 24 girls, 23 boys; mean age 4.06±0.42 years, body weight 17.71±2.81 kg, and body height 104.9±6.50 cm). Group II included children aged from the completion of the 5th year to the beginning of the 7th year (n=54; 23 girls and 31 boys; mean age 5.79±0.60 years, body weight 21.6±3.68 kg, and body height 116.6 ±7.59 cm). The standard MMT position was utilized for assessment.

Results
In the observed group, various methods of completing the test were identified (variants I, II, III, IV). Significant differences between groups (I and II) were observed only for variant II, both on the right (p=0.042) and left (p=0.012) sides of the body.

Conclusions
In the group of younger children, there is a preference for variants requiring the engagement of numerous muscle groups (variant IV), whereas in the older children's group, the predominant choice is a more isolated form of test performance (variant I). The selection of test variants is influenced by specific biometric parameters such as age, height, and weight. Gender was found to have no influence on the choice of variant.