A reflex response other than the normal response may be an indication of a disorder or complication in the nervous system.
| Reflex |
Description |
Disorder or Damage Indicated |
| Abdominal reflex |
Anterior stroking of the sides of lower torso causes contraction of abdominal muscles |
Absence of reflex indicates lesions of peripheral nerves or in reflex centers in lower thoracic segments of spinal cord; may also indicate multiple sclerosis |
| Plantar (Achilles) reflex |
Tapping of Achilles tendon of soleus and gastrocnemius muscles causes both muscles to contract, producing plantar flexion of foot |
Absence of reflex may indicate damage to nerves innervating posterior leg muscles or to lumbosacral neurons; may also indicate chronic diabetes, alcoholism, syphilis, or subarachnoid hemorrhage |
| Babinski’s reflex |
Stroking of lateral part of sole causes toes to curl (plantar reflex) |
Reflex indicates damage to upper motor neuron of pyramidal motor system |
| Biceps reflex |
Tapping of biceps tendon in elbow produces contraction of brachialis and biceps muscles, resulting in flexion at elbow |
Absence of reflex may indicate damage at the C5 or C6 vertebral level |
