US EPA

7323417 

Journal Article 

A proposal for a new classification of soleus muscle morphology 

Olewnik, Ł; Zielinska, N; Paulsen, F; Podgórski, M; Haładaj, R; Karauda, P; Polguj, M 

2020 

Yes 

Annals of Anatomy
ISSN: 0940-9602
EISSN: 1618-0402 

ELSEVIER GMBH 

MUNICH 

232 

151584 

English 

32810614 

10.1016/j.aanat.2020.151584 

WOS:000573299600013 

INTRODUCTION: The soleus muscle (SM) is located in the superficial posterior compartment of the leg, together with the gastrocnemius muscle (GM) and plantaris muscle. There is little information on the morphological variability (pennation) of the SM. The aim of the study is to characterize the variations in the morphology of the pennation of the SM and to create the first accurate classification.

MATERIAL AND METHODS: Eighty lower limbs (40 left, and 40 right) fixed in 10% formalin solution were examined. The morphology of the central tendon, medial and lateral aponeuroses was evaluated, together with the pennation angle.

RESULTS: In all cases, the soleus muscle was present. Four types could be distinguished based on muscle fibre morphology. In order of frequency: Type 1 - bipennate (43.75%); Type 4 - non-pennate (36.25%); Type 2 - unipennate (15%); Type 3 - multipennate (5%). No significant difference in type distribution was observed with regard to body side (p=0.9018) or gender (p=0.0844).

CONCLUSION: The soleus muscle is characterized by high morphological variability. Based on the pennation angle, four types (1-4) of soleus muscle are distinguishable.