Referred pain into the upper or lower extremities often accompanies back or neck pain. Referred pain can be the initial symptom of a compressed nerve root by a ruptured disc or neural foraminal stenosis from osteophytes. Radicular pain is usually described as sharp or even shock-like, and may be associated with certain activities or positions. The distribution of the pain may not always be classic, and often doesn’t respect dermatomal distributions.
Sensory changes are also often seen, with complaints of tingling and numbness being very common. On examination decreased sensation to pinprick and light touch are found in a dermatomal distribution in many patients. It is interesting that areas of referred pain and sensory loss often are different. Making determinations of level of nerve root compression solely from pain or sensory distribution is often difficult.
Motor weakness is also seen in nerve root compression syndromes. Muscle innervation is more constant and has less overlap than sensory innervation and is better at predicting level of pathology. Motor deficits that are of a more long-standing nature can have significant wasting. Hyporeflexia in the appropriate distribution is also seen.

Cervical

Cervical radiculopathy can present acutely, as with a traumatic ruptured disc, or can be of a more chronic and intermittent nature, as is seen in foraminal narrowing from osteophytes. Typically, the inferior nerve root is affected (e.g. C5-6 disc abnormalities affect the C6 nerve root). C5-6 and C6-7 are the most commonly affected segments.
A C5 radiculopathy typically presents with pain in the shoulder and the upper part of the lateral arm. Paresthesias are often seen in the more distal part of the affected dermatome. Deltoid weakness is seen commonly with a C5 radiculopathy. Biceps or brachioradialis weakness can be seen with a C6 radiculopathy along with the appropriate hyporeflexia. Paresthesias and frank sensory loss are more distal, and can extend into the hand. Root compression at C7 produces triceps weakness and a decreased triceps reflex. Pain extending into the distal forearm or hand is common. Sensory loss is commonly seen in the hand.

Lumbar

Sciatica is a classic syndrome of lower lumbar nerve root compression. Low back pain, that may or may not have been associated with some sort of trauma, is commonly antecedent to the onset of leg pain by days to a few weeks. Pain tends to be more proximal, and in a slightly different distribution than sensory changes. Motor weakness is also seen, but can be missed if dynamic testing is not done. All patients should be asked to stand on their toes and heels, as confrontational testing will miss subtle motor deficits in the lower extremities. As in the cervical spine, the pathologic level usually affects the caudal nerve root (e.g. L5-Sl disc produces an S1 radiculopathy). L5–S1 and L4–5 are overwhelmingly the most common levels affected. The upper lumbar spine is affected less frequently.

The classic S1 radiculopathy results in pain down the back of the leg and into the heel or foot. Sensory loss is usually over the lateral aspect of the foot. Plantar-flexion weakness is seen, but can be subtle. A loss of the Achilles reflex is also fairly specific to S1. The L5 radiculopathy produces similar pain, but the sensory symptoms tend to be over the dorsum of the foot. Weakness in dorsiflexion of the foot (or more specifically extensor hallicus longus) is the motor finding associated with L5. There is not a reliably reproducible reflex associated with L5.

Treatment options

Seeking treatment for radiculitis should not be delayed. Depending on the severity, certain muscles (ie: in the toes, feet and calf) may start to atrophy over time, which in turn requires physical therapy for recovery. Also, radiculitis is known to cause patients to "favor" certain muscles (or a certain side of their body) which can result in the over-development of those muscles relative to the ones that don't get used as much.
Initial treatment for the pain may involve one or a combination of the following interventions:

• One or two days of rest, if the pain is severe
• Analgesics or pain killers. Muscle relaxers.
• Non-steroidal anti-inflamatory drugs (NSAIDs).
• Acetaminophene, such as Tylenol, which helps reduce the pain signals in the brain
• Epidural steroidal injections, which involves injecting a steroid (and sometimes a pain killer) directly into the problem area in the low back to treat the inflammation that is irritating the nerve root
• Application of ice (to reduce the inflammation) and/or heat (to encourage blood flow to help the irritated area to heal)

Once the initial period of severe pain is under control, a variety of treatments may be employed to address the underlying cause of the pain, such as a disc herniation, spinal stenosis, or degenerative disc disease. 
Modifying personal habits and lifestyle to prevent future exacerbation of the underlying cause of the pain is also important. For example, maintaining an appropriate body weight that's knownnot to aggravate the discs (this varies from patient to patient) as well as changing the way one goes about bending over for objects on the ground (heavy or light, it doesn't matter...all one has to do is bend in the wrong direction to invoke an episode). Another important lifestyle change that is usually recommended is to maintain a regular stretching and exercise program.
There are also a variety of surgeries that be employed to treat severe cases of radicular pain, depending on the underlying condition that the surgery addresses. To treat a disc herniation, which may cause persistent radiating pain, a microdiscectomy surgery is usually performed. This is a minimally invasive approach that removes the portion of the disc that presses against the nerve root. The surgery has a high success rate, minimal healing time (typically the patient will go home on the same day as the surgery), and usually provides immediate relief of the sciatica and other symptoms caused by a herniated disc. This surgery may be recommended after several weeks of non-surgical treatment, or even earlier if the pain and other sciatica symptoms are severe.