1. Most arachnids lack extensor muscles in the distal joints of their appendages. 2. Finger flexor and extensor muscles are non-functional making grip of the implement difficult. 3. The extensor muscles are inhibited to prevent competition between the extensor and flexors. 4. Most often, the extensor muscles become painful due to tendon breakdown from over-extension. 5. The anterior five segments of the crayfish house the massive flexor and extensor muscles . 6. Conversely, an extensor muscle is the agonist in extension and the antagonist in flexion. 7. The body maintains the balance between the tone of flexor and extensor muscle groups. 8. Meanwhile, your shoulder extensor muscles contracted, so their receptors rested. 9. It happens because flexor muscles in the hand are so much stronger than extensor muscles . 10. These flattened tendons ( aponeurosis ) of extensor muscles span the proximal and middle phalanges.
