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Published on: December 19, 2019
Growth patterns of the brachioradialis muscle in the human fetus: anatomical study, digital image analysis,
Monika M Paruszewska-Achtel1, Dagmara Czyżykowska2, Tomasz Ciesielski2
1Department of Normal Anatomy, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, Bydgoszcz, Poland. monika.achtel@cm.umk.pl.
Insights
The brachioradialis muscle (BRM) in human fetuses shows minimal variability and no significant sex or side differences. Its development follows a proximal-to-distal growth pattern, consistent with other upper limb muscles.
Area of Science:
- Anatomy
- Developmental Biology
- Human Embryology
Background:
- The brachioradialis muscle (BRM) is a key component of the lateral extensor group in the forearm.
- Understanding its anatomical variations is crucial for clinical and research purposes.
Purpose of the Study:
- To investigate the morphometric variability of the brachioradialis muscle in human fetuses.
- To determine if sex or laterality influences BRM development.
- To analyze the growth pattern of the brachioradialis muscle.
Main Methods:
- Dissection and analysis of 100 human fetuses (20-34 weeks gestation).
- Utilized digital imaging and statistical analysis (Student's t-test, nonlinear estimation).
- Examined parameters including muscle surface area and tendon width.
Main Results:
- Minimal variability observed in the brachioradialis muscle across fetuses.
- No statistically significant differences found based on sex or laterality for most parameters.
- Muscle surface area and tendon width exhibited the greatest variability.
Conclusions:
- The brachioradialis muscle demonstrates low variability in fetal development.
- Sex and laterality do not significantly impact most BRM morphometric parameters.
- BRM growth follows a proximal-to-distal pattern, aligning with other upper limb muscles.
Background:
The brachioradialis muscle (BRM), among the extensor muscles of the forearm, is positioned most laterally and marks the beginning of the lateral extensor group of the forearm.
Materials And Methods:
The study was based on 100 human fetuses of both sexes (47♂ and 53♀), aged between 20 and 34 weeks of gestation. The fetuses, preserved in 10% buffered formalin solution, underwent conventional anatomical dissection to expose the lateral group of forearm extensors. Photographic documentation of the muscles in situ was analyzed using an optimized digital imaging system and subjected to statistical evaluation (including Student's t-test and nonlinear estimation).
Results:
For most of the parameters examined, no statistically significant differences were identified with respect to sex or laterality. The greatest variability was observed in muscle surface area and tendon width at mid-length. Derivatives of linear parameters were calculated to determine the rate of increase of these functions, confirming a faster growth rate in the proximal portion of the muscle compared with the distal portion of the BRM. These results corresponded with developmental patterns previously reported for upper limb musculature.
Conclusions:
1) The variability of the brachioradialis muscle (BRM) in the human fetus is minimal. 2) The BRM shows no sex- or side related (laterality) except for the morphometric parameters with the greatest overall variability (i.e., the largest mean-median differences and highest SDs) which are: tendon width at mid-length and muscle surface area. 3) BRM development follows a proximal-distal growth pattern, similar to other upper-limb muscles.
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