Radiculopathy is a diagnosis commonly made by physicians in primary care specialities, chiropractic, orthopedics, physiatry, and neurology. The diagnosis may be suggested by symptoms of pain, numbness, and weakness in a pattern consistent with the distribution of a particular nerve root. Neck pain or back pain may also be present. Physical examination may reveal motor and sensory deficits in the distribution of a nerve root. In the case of cervical radiculopathy, Spurling's test may elicit or reproduce symptoms radiating down the arm. In the case of lumbosacral radiculopathy, a Straight leg raise maneuver may exacerbate radiculopathic symptoms. Deep tendon reflexes (also known as a Stretch reflex) may be diminished or absent in areas innervated by a particular nerve root.

For further workup, the American College of Radiology recommends that projectional radiography is the most appropriate initial study in all patients with chronic neck pain. Two additional diagnostic tests that may be of use are magnetic resonance imaging and electrodiagnostic testing. Magnetic resonance imaging (MRI) of the portion of the spine where radiculopathy is suspected may reveal evidence of degenerative change, arthritic disease, or another explanatory lesion responsible for the patient's symptoms. Electrodiagnostic testing, consisting of NCS (Nerve conduction study) and EMG (Electromyography), is also a powerful diagnostic tool that may show nerve root injury in suspected areas. On nerve conduction studies, the pattern of diminished Compound muscle action potential and normal sensory nerve action potential may be seen given that the lesion is proximal to the Posterior root ganglion. Needle EMG is the more sensitive portion of the test, and may reveal active denervation in the distribution of the involved nerve root, and neurogenic-appearing voluntary motor units in more chronic radiculopathies. Given the key role of electrodiagnostic testing in the diagnosis of acute and chronic radiculopathies, the American Association of Neuromuscular & Electrodiagnostic Medicine has issued evidence-based practice guidelines, for the diagnosis of both cervical and lumbosacral radiculopathies. The American Association of Neuromuscular & Electrodiagnostic Medicine has also participated in the Choosing Wisely Campaign and several of their recommendations relate to what tests are unnecessary for neck and back pain.

The diagnosis process might include a physician who tests that the movement, strength, and sensation of the arms and legs are normal. The spine is examined for its range of motion and any pain that may arise from movement. Blood work might be utilized in addition to radiographic imaging in order to identify spinal cord diseases. Basic imaging techniques, which includes x-ray imaging, can reveal degenerative changes of the spine, while more advanced imaging techniques, such as computed tomography (CT) and magnetic resonance imaging (MRI), can allow visualization of more detailed anatomical structures, including that of the associated nerves and muscles. The most detailed and specific testing is electrodiagnostic, which helps to uncover whether the appropriate electrical signals are being sent to each muscle from the correlate nerves. This aids in localizing a problem's source. There are risks to be considered with any diagnostic testing. For example, in the case of CT imaging, there is obvious benefit over x-ray in that a more thorough picture of the anatomy is exposed, but there is a trade-off in that CT has around a 10-fold increased radiation exposure; alternatively, while MRI provides highly detailed imaging of the anatomy with the benefit of no radiation exposure to the patient, the high cost of this test must be taken into account.

Because there are various causes for back injuries, prevention must be comprehensive. Back injuries are predominant in manual labor so the majority low back pain prevention methods have been applied primarily toward biomechanics Prevention must come from multiple sources such as education, proper body mechanics, and physical fitness.

Ideally, effective treatment aims to resolve the underlying cause and restores the nerve root to normal function. Common conservative treatment approaches include physical therapy and chiropractic. A systematic review found moderate quality evidence that spinal manipulation is effective for the treatment of acute lumbar radiculopathy and cervical radiculopathy. Only low level evidence was found to support spinal manipulation for the treatment of chronic lumbar radiculopathies, and no evidence was found to exist for treatment of thoracic radiculopathy.

Surgery may be useful in those with a herniated disc that is causing significant pain radiating into the leg, significant leg weakness, bladder problems, or loss of bowel control. Discectomy (the partial removal of a disc that is causing leg pain) can provide pain relief sooner than nonsurgical treatments. Discectomy has better outcomes at one year but not at four to ten years. The less invasive microdiscectomy has not been shown to result in a significantly different outcome than regular discectomy with respect to pain. It might however have less risk of infection.

The presence of cauda equina syndrome (in which there is incontinence, weakness and genital numbness) is considered a medical emergency requiring immediate attention and possibly surgical decompression. Regarding the role of surgery for failed medical therapy in people without a significant neurological deficit, a Cochrane review concluded that "limited evidence is now available to support some aspects of surgical practice".

A spinal tap is performed in the low back with dye injected into the spinal fluid. X-Rays are performed followed by a CT scan of the spine to help see narrowing of the spinal canal.

This is a very effective study in cases of lateral recess stenosis. It is also necessary for patients in which MRI is contraindicated, such as those with implanted pacemakers.

MRI has become the most frequently used study to diagnose spinal stenosis. The MRI uses electromagnetic signals to produce images of the spine. MRIs are helpful because they show more structures, including nerves, muscles, and ligaments, than seen on x-rays or CT scans. MRIs are helpful at showing exactly what is causing spinal nerve compression.

Imaging is not typically needed in the initial diagnosis or treatment of back pain. However, if there are certain "red flag" symptoms present plain radiographs (x-ray), CT scan, or magnetic resonance imaging (MRI) may be recommended. These red flags include:

- History of cancer

- Unexplained weight loss

- Immunosuppression

- Urinary infection

- Intravenous drug use

- Prolonged use of corticosteroids

- Back pain not improved with conservative management

- History of significant trauma

- Minor fall or heavy lift in a potentially osteoporotic or elderly individual

- Acute onset of urinary retention, overflow incontinence, loss of anal sphincter tone, or fecal incontinence

- Saddle anesthesia

- Global or progressive motor weakness in the lower limbs

In most cases of low back pain, medical consensus advises not seeking an exact diagnosis but instead beginning to treat the pain. This assumes that there is no reason to expect that the person has an underlying problem. In most cases, the pain goes away naturally after a few weeks. Typically, people who do seek diagnosis through imaging are not likely to have a better outcome than those who wait for the condition to resolve.

Laboratory testing may include white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP).

- Elevated ESR could indicate infection, malignancy, chronic disease, inflammation, trauma, or tissue ischemia.

- Elevated CRP levels are associated with infection.

If one’s symptoms are mild, treatments like Massage, Exercise, and Stress management will suffice in reducing pain and pressure, but those with more severe symptoms are told to undergo unique therapies based on their exact situation. These patients most likely will have their postures and spine alignment fixed, and/or treatments like electrical stimulation may be used to help in reducing pain and aid in flexibility. Medicine, epidural injections and surgeries are also implemented to treat such a disorder.

The diagnosis may be confirmed by an EMG examination in 5 to 7 days. The evidence of denervation will be evident. If there is no nerve conduction 72 hours after the injury, then avulsion is most likely..

The most advanced diagnostic method is MR imaging of the brachial plexus using a high Tesla MRI scanner like 1.5 T or more. MR helps aid in the assessment of the injuries in specific context of site, extent and the nerve roots involved. In addition, assessment of the cervical cord and post traumatic changes in soft tissues may also be visualised.

The symptoms and signs depend on which nerve is affected, where along its length the nerve is affected, and how severely the nerve is affected. Positive sensory symptoms are usually the earliest to occur, particularly tingling and neuropathic pain, followed or accompanied by reduced sensation or complete numbness. Muscle weakness is usually noticed later, and is often associated with muscle atrophy.

A compression neuropathy can usually be diagnosed confidently on the basis of the symptoms and signs alone. However, nerve conduction studies are helpful in confirming the diagnosis, quantifying the severity, and ruling out involvement of other nerves (suggesting a mononeuritis multiplex or polyneuropathy). A scan is not usually necessary, but may be helpful if a tumour or other local compressive lesion is suspected.Nerve injury, as a mononeuropathy, may cause similar symptoms to compression neuropathy. This may occasionally cause diagnostic confusion, particularly if the patient does not remember the injury and there are no obvious physical signs to suggest it.The symptoms and signs of each particular syndrome are discussed on the relevant pages, listed below.

There are multiple techniques used in the diagnosis of spondylosis, these are;

- Cervical Compression Test, a variant of Spurling's test, is performed by laterally flexing the patient's head and placing downward pressure on it. Neck or shoulder pain on the ipsilateral side (i.e. the side to which the head is flexed) indicates a positive result for this test. However it should be noted that a positive test result is not necessarily a positive result for spondylosis and as such additional testing is required.

- Lhermitte sign: feeling of electrical shock with patient neck flexion

- Reduced range of motion of the neck, the most frequent objective finding on physical examination

- MRI and CT scans are helpful for pain diagnosis but generally are not definitive and must be considered together with physical examinations and history.

When an underlying medical condition is causing the neuropathy, treatment should first be directed at this condition. For example, if weight gain is the underlying cause, then a weight loss program is the most appropriate treatment. Compression neuropathy occurring in pregnancy often resolves after delivery, so no specific treatment is usually required. Some compression neuropathies are amenable to surgery: carpal tunnel syndrome and cubital tunnel syndrome are two common examples. Whether or not it is appropriate to offer surgery in any particular case depends on the severity of the symptoms, the risks of the proposed operation, and the prognosis if untreated. After surgery, the symptoms may resolve completely, but if the compression was sufficiently severe or prolonged then the nerve may not recover fully and some symptoms may persist. Drug treatment may be useful for an underlying condition (including peripheral oedema), or for ameliorating neuropathic pain.

Initial treatment in lumbar disc disease is one or two days of bedrest (although growing number of studies shows that it makes little difference) and pain relieving medications. In cases with ongoing pain despite conservative treatments, a surgical operation that will remove the compressing disc material, a microdiscectomy or discectomy may be recommended to treat a lumbar disc herniation.

The severity of brachial plexus injury is determined by the type of nerve damage. There are several different classification systems for grading the severity of nerve and brachial plexus injuries. Most systems attempt to correlate the degree of injury with symptoms, pathology and prognosis. Seddon's classification, devised in 1943, continues to be used, and is based on three main types of nerve fiber injury, and whether there is continuity of the nerve.

1. Neurapraxia: The mildest form of nerve injury. It involves an interruption of the nerve conduction without loss of continuity of the axon. Recovery takes place without wallerian degeneration.

2. Axonotmesis: Involves axonal degeneration, with loss of the relative continuity of the axon and its covering of myelin, but preservation of the connective tissue framework of the nerve (the encapsulating tissue, the epineurium and perineurium, are preserved).

3. Neurotmesis: The most severe form of nerve injury, in which the nerve is completely disrupted by contusion, traction or laceration. Not only the axon, but the encapsulating connective tissue lose their continuity. The most extreme degree of neurotmesis is transsection, although most neurotmetic injuries do not produce gross loss of continuity of the nerve but rather, internal disruption of the nerve architecture sufficient to involve perineurium and endoneurium as well as axons and their covering. It requires surgery, with unpredictable recovery.

A more recent and commonly used system described by the late Sir Sydney Sunderland, divides nerve injuries into five degrees: first degree or neurapraxia, following on from Seddon, in which the insulation around the nerve called myelin is damaged but the nerve itself is spared, and second through fifth degree, which denotes increasing severity of injury. With fifth degree injuries, the nerve is completely divided.

Facet syndrome can typically be diagnosed through a physical examination, MRI, x-rays and/or a diagnostic block into the suspected joint.

Facet syndrome has no specific code in ICD-10. It can be diagnosed as “other” in M53.8 – other specified dorsopathies.

Radicular pain, or radiculitis, is pain "radiated" along the dermatome (sensory distribution) of a nerve due to inflammation or other irritation of the nerve root (radiculopathy) at its connection to the spinal column. A common form of radiculitis is sciatica – radicular pain that radiates along the sciatic nerve from the lower spine to the lower back, gluteal muscles, back of the upper thigh, calf, and foot as often secondary to nerve root irritation from a spinal disc herniation or from osteophytes in the lumbar region of the spine.

The diagnosis depends on appropriate patient history backed by imaging studies like X ray and MRI. Lumbosacral spine radiographs help in the identification of the skeletal abnormality. MRI helps in confirmation.

Treatment is usually conservative in nature. Patient education on lifestyle modifications, chiropractic, nonsteroidal anti-inflammatory drugs (NSAIDs), physical therapy, and osteopathic care are common forms of manual care that help manage such conditions. Other alternative therapies such as massage, trigger-point therapy, yoga and acupuncture may be of limited benefit. Surgery is occasionally performed.

Many of the treatments for cervical spondylosis have not been subjected to rigorous, controlled trials. Surgery is advocated for cervical radiculopathy in patients who have intractable pain, progressive symptoms, or weakness that fails to improve with conservative therapy. Surgical indications for cervical spondylosis with myelopathy (CSM) remain somewhat controversial, but "most clinicians recommend operative therapy over conservative therapy for moderate-to-severe myelopathy" (Baron, M.E.).

Physical therapy may be effective for restoring range of motion, flexibility and core strengthening. Decompressive therapies (i.e. manual mobilization, mechanical traction) may also help alleviate pain. However, physical therapy and osteopathy cannot "cure" the degeneration, and some people view that strong compliance with postural modification is necessary to realize maximum benefit from decompression, adjustments and flexibility rehabilitation.

It has been argued, however, that the cause of spondylosis is simply old age, and that posture modification treatment is often practiced by those who have a financial interest (such as Worker's Compensation) in proving that it is caused by work conditions and poor physical habits. Understanding anatomy is the key to conservative management of spondylosis.

As with many conditions without clear physical or laboratory diagnosis, TN is sometimes misdiagnosed. A TN sufferer will sometimes seek the help of numerous clinicians before a firm diagnosis is made.

There is evidence that points towards the need to quickly treat and diagnose TN. It is thought that the longer a patient suffers from TN, the harder it may be to reverse the neural pathways associated with the pain.

The differential diagnosis includes temporomandibular disorder. Since triggering may be caused by movements of the tongue or facial muscles, TN must be differentiated from masticatory pain that has the clinical characteristics of deep somatic rather than neuropathic pain. Masticatory pain will not be arrested by a conventional mandibular local anesthetic block. One quick test a dentist might perform is a conventional inferior dental local anaesthetic block, if the pain is in this branch, as it will not arrest masticatory pain but will TN.

Trigeminal neuralgia is diagnosed via the result of neurological and physical test, as well as the individuals medical history.

A thorough medical history and physical examination, including a neurological examination, are the first steps in making a diagnosis. This alone may be sufficient to diagnose Bell's Palsy, in the absence of other findings. Additional investigations may be pursued, including blood tests such as ESR for inflammation, and blood sugar levels for diabetes. If other specific causes, such as sarcoidosis or Lyme disease are suspected, specific tests such as angiotensin converting enzyme levels, chest x-ray or Lyme titer may be pursued. If there is a history of trauma, or a tumour is suspected, a CT scan may be used.

Pain, loss of muscle strength and loss of touch sensation may occur if this herniation causes the compression of the most proximal part of the nerve closely neighbouring the intervertebral disc material. Pain is in the distribution of the nerve compressed, usually down the back of the leg, side of the calf and inside of the foot (sciatica). Most commonly, the nerve root between the fourth and fifth lumbar vertebrae or between the fifth lumbar vertebra and first sacral segment are impinged.

In symptomatic cases the diagnosis should be confirmed by an MRI scan. However, in cases with slight symptoms, a faster and cheaper CT scan (although it is inferior to MRI scan) may be recommended. While a CT scan can show the bony structures in more detail, an MRI scan can better portray soft tissue.

Initial diagnosis often is made during routine physical examination. Such diagnosis can be confirmed by a medical professional such as a neurologist, orthopedic surgeon or neurosurgeon. A person with foot drop will have difficulty walking on his or her heels because he will be unable to lift the front of the foot (balls and toes) off the ground. Therefore, a simple test of asking the patient to dorsiflex may determine diagnosis of the problem. This is measured on a 0-5 scale that observes mobility. The lowest point, 0, will determine complete paralysis and the highest point, 5, will determine complete mobility.

There are other tests that may help determine the underlying etiology for this diagnosis. Such tests may include MRI, MRN, or EMG to assess the surrounding areas of damaged nerves and the damaged nerves themselves, respectively. The nerve that communicates to the muscles that lift the foot is the peroneal nerve. This nerve innervates the anterior muscles of the leg that are used during dorsi flexion of the ankle. The muscles that are used in plantar flexion are innervated by the tibial nerve and often develop tightness in the presence of foot drop. The muscles that keep the ankle from supination (as from an ankle sprain) are also innervated by the peroneal nerve, and it is not uncommon to find weakness in this area as well. Paraesthesia in the lower leg, particularly on the top of the foot and ankle, also can accompany foot drop, although it is not in all instances.

A common yoga kneeling exercise, the Varjrasana has, under the name "yoga foot drop," been linked to foot drop.