Today's post from mmcneuro.wordpress.com (see link below) takes a good look at what's called sciatic neuropathy. People who discover they are getting strange symptoms in their feet or legs may well be confused from the outset. Where are they coming from; what's causing them and how can you distinguish one possible cause from another? Bearing in mind that neuropathy basically means nerve damage, there are over 100 sorts and over 100 causes. One of the possible causes is nerve entrapment which can lead to radiculopathy which is the trapped nerve neuropathy. This is one of the neuropathies that may be able to be helped by surgery releasing the trapped nerve. If you are also having sciatic pain from your lower spine to your feet and down the backs of your legs, this article may help you see the wood for the trees but it is confusing for a patient new to the problems and symptoms. Your neuropathy may have nothing to do with trapped nerves but the more information you have, the more likely it is you will understand what the doctor or specialist is talking about and looking for. This article is also interesting for people with other forms of neuropathy affecting the feet and legs.
Sciatic Neuropathy February 13, 2013 Neurology Update
A neurology education blog from Dr Holland and The Monmouth Neuroscience Institute
The terms lumbar radiculopathy and sciatica are used interchangeably to indicate radiating pain, numbness and weakness in a leg from a pinched nerve root in the back.
However, it is important to recognize that similar symptoms and signs can be caused by injury or compression of the sciatic nerve outside the spine, either in the buttock or thigh.
The sciatic nerve is the longest and widest nerve in the body, extending from the spine all the way to the foot, and contributes most of the nerve supply to the leg:
Sciatic nerve injury presents with:
1. Numbness affecting the entire leg, aside from the front of the thigh.
2. Weakness of the hamstrings, and all movement at the ankle.
3. Absent ankle jerk.
Sciatic Nerve Injury in the Buttock:
The nerve can be injured by misplaced buttock injections, gunshot wounds and knife injury. Buttock injections should be given in the upper outer quadrant to avoid the sciatic nerve
The sciatic nerve injury can also be injured by prolonged sitting on a toilet seat, either from direct nerve compression or hemorrhage and compartment syndrome into the gluteal muscles. This has been reported in cases of severe prolonged diarrhea, or drug induced coma on the toilet, so called toilet seat neuropathy.
Sciatic Nerve Injury at the Hip:
The sciatic nerve runs behind the hip joint as it travels through the buttock.
The sciatic nerve is frequently injured by a posterior dislocation of the hip:
Sciatic nerve injury occurs in as many as 1%–3% of patients who undergo total hip replacement surgery, usually from a stretch injury to the nerves, but occasionally from a misplaced crew, broken piece of wire, fragment of bone or cement pressing on the nerve:
Sciatic nerve injury after hip arthroplasty. (a) The skin incision for the transgluteal approach is in a continuous line. The cross on the left shows the ischium and the one on the right shows the trochanter. Between them, the skin projection of the sciatic nerve is seen. (b) The sciatic nerve was freed from all attachments. The arrows identify acrylic material from the hip arthroplasty, which was damaging the nerve
Piriformis Syndrome:
However, symptoms of sciatic neuropathy most often result from nerve compression by the piriformis muscle at the level of the sciatic notch, so-called piriformis syndrome.
This presents with buttock tenderness and pain, radiate down the posterior thigh. Symptoms are made worse by prolonged sitting, bending at the waist, and activities involving hip adduction and internal rotation. The pain can be reproduced by deep palpation over the sciatic notch.
Diagnostic modalities such as CT, MRI, ultrasound, and EMG may all be normal in piriformis syndrome, but are still useful for excluding other conditions.
Magnetic resonance neurography is a specialized imaging technique which can confirm the presence of sciatic nerve irritation or injury of the sciatic nerve in the piriformis muscle.
MRN findings in piriformis syndrome. A: Axial T1-weighted image of piriformis muscle size asymmetry (arrows indicate piriformis muscles). The left muscle is enlarged. B and C: Coronal and axial images of the pelvis (arrows indicate sciatic nerves). The left nerve exhibited hyperintensity. D: Curved reformatted neurography image demonstrating left sciatic nerve hyperintensity and loss of fascicular detail at the sciatic notch (arrows).
Conservative treatment can include medications, physical therapy and stretching, or injection of a paralysing agent such as botulinum toxin into the piriformis muscle under ultrasound or CT control. Surgery may be necessary for recalcitrant cases.
http://mmcneuro.wordpress.com/2013/02/13/sciatic-neuropathy/
Today's post from healthmeup.com (see link below) is a good and easy to follow description from India of the nervous system; the symptoms when there is nerve damage and the common testing process to make diagnoses. Many people with neuropathy aren't quite sure which nerves are which, what their functions are and why they go wrong - this article provides you with a simple explanation without overwhelming you with information. Definitely worth a read to top up your knowledge.
Understanding Peripheral Nerves : Types, Peripheral Neuropathy, Symptoms and Tests By Sobiya N. Moghul posted Aug 20th 2014 Healthy Living
The human nervous system consists of four parts: the brain, spinal cord, autonomic nervous system and peripheral nerves. Peripheral nerves are cord-like structures containing bundles of nerve fibres that transmit signals from the spinal cord to the rest of the body, or to transmit sensory information from the rest of the body to the spinal cord. Your peripheral nerves are the ones outside your brain and spinal cord. Like static on a telephone line, peripheral nerve disorders distort or interrupt the messages between the brain and the rest of the body.
The nerves in our bodies are very similar to electric cables. The brain and spinal cord send electrical signals through the nerves to different muscles. The muscles, in turn, have a specialised mechanism to properly understand the electrical signals and act accordingly, thereby moving different parts of the body.
There are three types of peripheral nerves: motor, sensory and autonomic. Some neuropathies affect all three types of nerves, while others involve only one or two.
Motor nerves send impulses from the brain and spinal cord to all of the muscles in the body. This permits people to perfom activities like walking, catching a ball, or moving the fingers to pick something up. Motor nerve damage can lead to muscle weakness, difficulty in walking or moving the arms, cramps and spasms.
Sensory nerves send messages in the other direction—from the muscles back to the spinal cord and the brain. Special sensors in the skin and deep inside the body help people identify if an object is sharp, rough, or smooth, if it's hot or cold, or if a body part is still or in motion. Sensory nerve damage often results in tingling, numbness, pain, and extreme sensitivity to touch.
Autonomic nerves control involuntary or semi-voluntary functions, such as heart rate, blood pressure, digestion, and sweating. When the autonomic nerves are damaged, a person's heart may beat faster or slower. They may get dizzy when standing up, sweat excessively, or have difficulty sweating at all.
There are various kinds of peripheral nerve disorders. They can affect one nerve( mononeuropathy) or many nerves( polyneuropathy). In some cases, like complex regional pain syndrome and brachial plexus injuries, the problem begins after an injury. Some people are born with peripheral nerve disorders.
Mononeuropathy is usually the result of damage to a single nerve or nerve group by trauma, injury, local compression, prolonged pressure, or inflammation. Examples include: Carpal tunnel syndrome (a painful wrist and hand disorder often associated with repetitive tasks), and Bell's palsy (a facial nerve disorder) .
The majority of people, however, suffer from polyneuropathy, an umbrella term for damage involving many nerves at the same time.
There are many causes of peripheral neuropathy, including diabetes, hereditary disorders, infections, inflammation, auto-immune diseases, protein abnormalities, exposure to toxic chemicals, poor nutrition, kidney failure, chronic alcoholism, and certain medications – especially those used to treat cancer and HIV/AIDS. In some cases, however, even with extensive evaluation, the cause of a person's peripheral neuropathy remains unknown – this is called idiopathic neuropathy.
The symptoms of peripheral neuropathy often include:
• A sensation of wearing an invisible "glove" or "sock"
• Burning sensation or freezing pain
• Sharp, jabbing or electric-like pain
• Extreme sensitivity to touch
• Difficulty sleeping because of feet and leg pain
• Loss of balance and coordination
• Muscle weakness
• Difficulty walking or moving the arms
• Unusual sweating
• Abnormalities in blood pressure or pulse
There are specialised nerve tests like EMG, NCV and SSEP, which are designed to diagnose any abnormality in the functioning of these nerves.
EMG, or Electromyography is a technique used for evaluating and recording the electrical activity produced by muscles. The EMG helps doctors distinguish between muscle conditions that begin in the muscle and nerve disorders that cause muscle weakness.
NCV, or Nerve Conduction Velocity, is an electrical diagnostic test that provides information about abnormal conditions in the nerves.
SSEP, or Somatosensory Evoked Potential, is a test showing the electrical signals of sensation going from the body to the brain and spinal cord. The signals show whether the nerves that connect to the spinal cord are able to send and receive sensory information like pain, temperature and touch.
Treatment aims to treat any underlying problem, reduce pain and control symptoms. Injuries to the Brain and Spinal cord have only a very limited capacity to heal, because nerve regeneration tends not to occur. In contrast, peripheral nerves have a striking capacity for regeneration. Even completely severed peripheral nerves, if repaired in a timely fashion, can regrow, allowing the patients to enjoy complete, or nearly complete recovery in many cases.
The healing process almost invariably requires an extensive amount of time to occur. It is important for patients not to lose hope during this time. It is vital that they exercise, keeping the affected muscles and joints flexible and ready to be used once again when the axons regrow into them. It is not unusual for patients to undergo a lengthy, complex, peripheral nerve reconstruction procedure, only to see no evidence of recovery for a year or more. This can be immensely frustrating for the patient. Unfortunately, currently there is nothing in medical science that can make these axons grow any faster. Perhaps it is best to think of this delay as part of the healing process, paving the road to further recovery.
*Inputs : Dr Harleen Luther – Brain , Spine; Peripheral Nerve Surgeon, Seven Hills Hospital, Mumbai.
http://healthmeup.com/news-healthy-living/understanding-peripheral-nerves-types-peripheral-neuropathy-symptoms-and-tests/23706
