Sensory Ataxia is caused by a lack of sensory input into movement control, in contrast to cerebellar impairment, which can induce Ataxia. Ataxia or decreased coordination of voluntary muscular action is a physical finding, not a disorder.
Sensory Ataxia causes unsteady walking, and, specifically, it may affect the ability to balance with closed eyes or in the dark (in situations like showering). Loss of proprioception (the ability to know where one's body parts are concerning others and the ground) underlies sensory Ataxia, which manifests as uncoordinated musculoskeletal movements.
High-stepping gaits (related to motor weakness) and feet-slapping gaits are two possible walking patterns for people with sensory Ataxia (to assist with sound-induced sensory feedback). It is possible for pseudoarthrosis happens in cases of sensory neuronopathy affecting the upper limbs.
Damage to the nerves that send continuous feedback from the position sensors in the joints and muscles to the brain's movement control center results in sensory Ataxia. While compared to cerebellar Ataxia, sensory Ataxia is characterized by the patient's near-normal coordination of the affected movement. At the same time, their eyes are open, but a dramatic worsening of coordination when their eyes are closed.
Cerebellar ataxia symptoms are absent in sensory ataxia patients, including pendular tendon reflexes, scanning dysarthria, nystagmus, and broken pursuit eye movements. People who have sensory Ataxia frequently show Romberg's sign and pseudoarthrosis. When they close their eyes in the shower or take off a shirt over their head, they often feel dizzy and unsteady.
Sensory Ataxia occurs in disorders that affect the spinal cord's dorsal columns, such as tabes dorsalis, or in the absence of a healthy sensory peripheral nervous system.
Causes of Sensory Ataxia
Damage to the spinal cord or nerves that travel to the limbs, including the feet and legs, is the most common cause of sensory Ataxia. Several factors, including systemic disorders like diabetes and multiple sclerosis, spinal cord compression, and exposure to poisons like lead, mercury, and arsenic, can damage the nerves in the feet, hands, and torso, causing a person to lose sensation in those areas. Sensory Ataxia is typically brought on by:
- Brain hemorrhage
- Cerebral palsy
- Diabetes mellitus
- Friedreich Ataxia
- Guillain-Barré syndrome
- Head trauma
- Neuropathy type 3, a hereditary disorder affecting the senses and muscles,
- Multiple Sclerosis
- Peripheral Neuropathies
- Peripheral neuropathies
- Sensory neuropathy
- Spinal cord compression
- Tabes dorsalis
- A toxic response
- Deficiency of vitamin E
- Lack of vitamin B-12
- Vitamin B1 (thiamine) deficiency
When a person has sensory Ataxia, they may lose sensation in their feet and legs, causing them to walk as if they were "walking on pillows" with an unstable, possibly stomping pace. Leg and feet soreness and pain are possible side effects. The patient typically walks with a downward gaze, and feet slap the earth as they are thrown. Trouble is less likely to occur on well-worn paths than on unfamiliar ones.
Because the brain relies more heavily on visual information to determine body position when the eyes are closed or when there is little light, instability and imbalance are exacerbated.
Furthermore, those who suffer from sensory Ataxia will exhibit a positive Romberg sign. The inability to maintain a 60-second foot-and-eye-closed stance is a Romberg sign.
Patients with tabes dorsalis have significant sensory Ataxia due to syphilitic damage to the dorsal columns of the spinal cord, and Romberg's sign pieces evidence this. Patients with cerebellar Ataxia and more than half of patients with sensory Ataxia could hold this position for 60 seconds. Still, patients with sensory Ataxia could hold it for only 10 seconds.
Sensory Ataxia Diagnosis
Sometimes nerve conduction studies are needed, but in most cases, a thorough neurological evaluation, including checking your concentration and memory, vision, hearing, balance, coordination, and reflexes, and a review of your medical history, will make a clinical diagnosis of sensory Ataxia.
Your doctor will investigate possible curable causes of your Ataxia. Your doctor may order laboratory tests after doing a physical and neurological examination.
- Investigations using imaging techniques: A brain CT or MRI could help determine specific possible causes. In some cases of Ataxia, an MRI will reveal atrophy of brain regions, including the cerebellum. The results could potentially reveal the presence of a benign tumor or blood clot that is putting pressure on your cerebellum and can be treated.
- Lumbar Puncture (spinal tap): To obtain a cerebrospinal fluid sample, a needle is placed between two lumbar vertebrae in the lower back (lumbar area). The fluid that bathes and cushions your brain and spinal cord is collected and transported to a lab for analysis.
- Genetic testing: If you or your kids have symptoms consistent with one of the hereditary ataxic diseases, your doctor may offer genetic testing. Many forms of hereditary Ataxia can be diagnosed with a gene test, but not all.