What does no ankle reflex indicate?
A patient with low back pain or sciatica and an absent ankle reflex is often seen by orthopaedic and spinal sur- geons. An absent ankle reflex has been described as a definite neurological sign, possibly indicating nerve-root compression (Maurice-Williams 1987; Frymoyer 1991; Donaghy 1993; Dickson and Butt 1995).
What does absent Achilles reflex mean?
Your doctor will use a rubber hammer to tap firmly on the Achilles tendon, which connects the muscle at the back of your calf to your heel bone. In a normal test, your foot will move as though you were going to point your toes. A decreased or absent reflex may mean that there is compression in the S1 region.
What causes loss of tendon reflex?
Peripheral neuropathy is today the most common cause of absent reflexes. The causes include diseases such as diabetes, alcoholism, amyloidosis, uremia; vitamin deficiencies such as pellagra, beriberi, pernicious anemia; remote cancer; toxins including lead, arsenic, isoniazid, vincristine, diphenylhydantoin.
Which nerve is responsible for ankle reflex?
The ankle jerk reflex is mediated by the S1 nerve root. The plantar reflex (Babinski) is tested by coarsely running a key or the end of the reflex hammer up the lateral aspect of the foot from heel to big toe. The normal reflex is toe flexion.
Why is the ankle jerk reflex important?
The ankle jerk reflex, also known as the Achilles reflex, occurs when the Achilles tendon is tapped while the foot is dorsiflexed. It is a type of stretch reflex that tests the function of the gastrocnemius muscle and the nerve that supplies it.
What does absent ankle jerk mean?
Absent ankle jerk The Achilles reflex checks if the S1 and S2 nerve roots are intact and could be indicative of sciatic nerve pathology. It is classically delayed in hypothyroidism. This reflex is usually absent in disk herniations at the L5—S1 level.
What happens when you have no reflex actions?
When reflex responses are absent this could be a clue that the spinal cord, nerve root, peripheral nerve, or muscle has been damaged. When reflex response is abnormal, it may be due to the disruption of the sensory (feeling) or motor (movement) nerves or both.
What happens if the reflex arc is damaged?
The skin tissue is key to the entire initiation of the reflex because, when damaged, it releases chemicals to induce the activation of the sensory neurons that further the completion of the reflex. The peripheral nervous system includes the sensory neurons that are stimulated by noxious input.
Which nerve root is affected in a patient with loss of the ankle jerk reflex?
A reduced or absent ankle jerk reflex can indicate pathology of the tibial and/or sciatic nerve.