Extensor Carpi Radialis Longus Anatomy
Origin: Humerus (lateral supracondylar ridge, distal 1/3)
Common forearm extensor tendon
Lateral intermuscular septum
Insertion: 2nd metacarpal bone (base on radial side of dorsal aspe
Innervation: Cervical root(s): C6 and C7
Nerve: radial nerve (lateral muscular branch)
Diagrams & Photos
Key Points
- The ECRL is contained in the second extensor compartment of the wrist.
- The ECRL is considerably stronger than the extensor carpi ulnaris (ECU).
- A patient with complete quadriplegia at C5–C6 will have only radial wrist extensors functioning; therefore, radial deviation during extension will be observed on attempted active wrist extension.
- Intersection Syndrome is caused by inflammation in the area between the radial wrist extensors (ECRB&ECRL) and the thumb abductor and extensor (APL & EPB).