The nerve roots primarily responsible for ankle dorsiflexion are L4 and L5.
Dorsiflexion refers to the movement of the foot upwards at the ankle joint, bringing the toes towards the shin. While several muscles contribute to this action, they are innervated by specific nerve roots originating in the lumbar spine.
Here's a breakdown:
- L4: This nerve root is a major contributor to ankle dorsiflexion.
- L5: L5 also plays a significant role in dorsiflexion, working in conjunction with L4.
| Nerve Root | Primary Motion | Sensory |
|---|---|---|
| L4 | Ankle dorsiflexion | Lateral thigh, anterior knee, medial leg |
| L5 | Toe dorsiflexion, Foot inversion | Lateral leg, dorsal foot |
It is important to note that while L4 and L5 are the primary nerve roots involved, other nerve roots can indirectly contribute to ankle dorsiflexion through their innervation of synergistic muscles.
