Occipitofrontalis
Occipitofrontalis is a muscle which covers a large area of the skull. It has two anterior and two posterior bellies divided by aponeurosis. They are connected by an intermediate tendon.
The frontal bellies are positioned anteriorly whilst the occipital bellies are positioned posteriorly.
Its function is for facial expression with contraction wrinkling the scalp and raising the eyebrows.
Clinical relevance
1. In unilateral facial paralysis forehead sparing can be used to distinguish between UMN and LMN lesions. In UMN lesions such as brain tumours the forehead is spared. In LMN lesions such as idiopathic Bell's palsy the forehead is paralysed.
2. In cosmetic procedures the occipitofrontalis is injected with botox to reduce forehead wrinkles.
The frontal bellies are positioned anteriorly whilst the occipital bellies are positioned posteriorly.
Its function is for facial expression with contraction wrinkling the scalp and raising the eyebrows.
Key anatomical information
| Parameter | Details |
|---|---|
| Innervation | Facial nerve |
| Insertion (both bellies) | Galea aponeurotic |
| Origin occipital belly | Lateral two thirds nuchal line mastoid process of temporal bone |
| Origin frontal belly | fascia of facial muscles skin above eyes and nose |
 | |
Clinical relevance
1. In unilateral facial paralysis forehead sparing can be used to distinguish between UMN and LMN lesions. In UMN lesions such as brain tumours the forehead is spared. In LMN lesions such as idiopathic Bell's palsy the forehead is paralysed.
2. In cosmetic procedures the occipitofrontalis is injected with botox to reduce forehead wrinkles.