Upper limb
Pronator Teres (humeral head)
Musculus pronator teres (caput humerale)
- Origin
- Medial epicondyle of the humerus (common flexor origin)
- Insertion
- Lateral side of the radial shaft, midway along its length
- Function
- Pronates the forearm; weak flexor of the elbow
- Innervation
- Median nerve, C6–C7
- Movement & chain
- Works together with pronator quadratus, which handles the terminal phase of pronation while pronator teres primarily provides force from extended/flexed elbow positions.
- Palpation
- Palpable as the most proximal, obliquely oriented muscle belly on the volar forearm, just distal to the elbow crease, during resisted pronation.
- Clinical
- Pronator teres syndrome is a rare compression of the median nerve between the two heads of this muscle, causing sensory symptoms in the median nerve territory without nocturnal worsening (unlike carpal tunnel syndrome).
- Segmental innervation
- Median nerve, C6–C7.
- In clinical practice
- The muscle belly serves as a landmark for locating the median nerve in the proximal forearm, for example in ultrasound-guided interventions.
- Region in the model
- Upper limb