Lumbar Radiculopathy Assessment

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Top Contributors - Jess Bell, Matt Huey and Wanda van Niekerk  

Introduction

Lumbar radiculopathy is commonly defined when a person is experiencing pain symptoms that radiate into the legs. There can be variances in the descriptions from sharp, shooting, shocks, numbness, and tingling, which are based upon a patient's interpretation of the symptoms. It affects approximately 3-5% of the population and is the most common issue that spine surgeons evaluate. Patients also may or may not experience back pain along with radiculopathy but roughly 12-40% of people with back pain experience radiculopathy symptoms as well.

Causes of Radiculopathy

The primary cause of lumbar radiculopathy is compression of the nerve root. It is commonly believed to be caused by a disc herniation or bulge pressing on the nerve but there can be a variety of causes such as:

• Degenerative conditions: Spondylolisthesis, Spinal Stenosis, Osteophytes
• Trauma: Fractures
• Tumors
• Infections
• Vascular conditions: hemangioblastoma, arteriovenous malformations

Assessment for Radiculopathy

It is important when patients present with radicular symptoms to perform an assessment to not only ensure a proper diagnosis and treatment, but also to rule out red flag symptoms. If red flag symptoms are found, it is important to refer out. Red flags include:

• Fever
• Unexplained weight loss
• Bowel or bladder dysfunction
• Saddle anesthesia
• Gait ataxia

When performing an assessment of a patient with a lumbar radiculopathy, the following are typically done:

• Myotomes/MMT
• Sensation
• Deep tendon reflexes
• Neurodynamics
• Repeated movements

There is research that has found that physical tests are poor when performed in isolation, but when tests are used in combination the results do improve. Keep in mind, you can utilize these tests as a test and retest measure to show improvement.

Myotomes

Since with a lumbar radiculopathy the nerve root is involved, patients may experience a loss of strength in their lower extremities. With manual muscle testing of the myotomes, the therapist gains insight on the possible level of a lesion or compression on the nerve root.

To test myotomes:

• Have the patient seated to allow their lower extremity to move against gravity
• Instruct the patient in what you will be doing such as "I want you to lift your leg up and hold it while I press down on it."
• Have the patient move their lower extremity to the testing position
• Ask them to hold while you place a gradually increasing downward force on their extremity.
• Instruct the patient to hold for 3 seconds (helps to say Hold, Hold, Hold)
• Record the patient's strength
• Repeat for opposite side

Nerve Root	Lower Extremity Movement
L2	Hip Flexion
L3	Knee Extension
L4	Ankle Dorisiflexion
L5	Big Toe Extension
S1	Ankle Plantarflexion
S2	Knee Flexion

Do keep in mind that manual muscle testing can vary depending on both the patient's and therapist's size and strength. It can be useful as well to ask a patient if they feel the strength in each lower extremity feels the same after testing. A patient may test strong but tell you that one side did not feel as strong as the other.

Sensation

Patients may experience a change in sensation in their lower extremities with a lumbar radiculopathy. A common complaint with lumbar radiculopathy is numbness and tingling in the legs along a dermatomal pattern. Patients may also state they feel "weird" sensations in their lower extremities as well, such as the feeling of bugs crawling on them, tenderness, or "it doesn't feel right."

Light touch can be utilized to determine if sensation is altered.

• Have the patient in the supine or seated position
• Inform them what you will be doing. "I will be brushing along your legs in certain areas, let me know if it feels the same on both sides."
• Can have the patient close their eyes or obscure their view so they are not biased to the testing
• Use your fingertips or a cotton swab to apply a light touch to a dermatome.
• Test each side and compare if it feels the same.
• To ensure consistency, utilize the same dermatomal map with each patient

Dermatome	Area
L1	Greater trochanter
L2	Front of thigh to knee
L3	Anterior thigh and Knee, medial lower leg
L4	Lateral thigh, medial leg, dorsum of foot, big toe
L5	Posterior and lateral thigh, lateral aspect of leg, dorsum of foot, medial half of bottom of foot, toes 1-3
S1	Posterior thigh

Deep Tendon Reflexes

Reflexes may or may not be altered with a lumbar radiculopathy, however, it can be beneficial to assess. If the nerve root is being compromised then the patient may demonstrate diminished reflexes. For patients with a lumbar radiculopathy, the testing will be the patellar and Achille's reflexes. The testing is as follows:

• The patient can be either seated or lying down (prone and supine)
• Palpate the tendon to ensure to proper identification
• Make sure the patient is relaxed
• Using a reflex hammer, perform a brisk, firm strike to the tendon.
• Can repeat as necessary
• If a response is not found or the patient cannot relax, have the patient perform a jendrassik manoeuvre, such as clinching their jaw or trying to pull their hands apart.

Reflex	Nerve Supply	Segmental Innervation	Area to test	Expected Response
Patellar	Femoral nerve	L2-L4	Patella tendon	Leg extension
Achilles	Tibial nerve	S1-2	Achilles tendon	Plantarflexion

Repeated Movement

The use of repeated movement testing is a hallmark of Mechanical Diagnosis and Therapy (MDT or the McKenzie Method). The goal with utilizing repeated movement testing, is to determine if the person is able to centralize their radicular symptoms. There is evidence that utilizing repeated movement testing can be both useful in the assessment and treatment for lumbar radiculopathy. Repeated movement testing can be useful even if a patient is only experiencing symptoms in their lower extremity.

Several things must be considered when performing repeated movement:

• Direction. Often a mistake is only performing repeated extension.
• Loaded or unloaded. Standing is considered a loaded position of the lumbar spine whereas supine/prone is considered unloaded.
• Time and/or repetition. Another mistake that can be made is not giving enough time or the proper number of repetitions to exhaust a movement.

Conclusion

Performing these test can be not only important for diagnosing a lumbar radiculopathy but also ruling out serious pathologies and other causes of radicular symptoms not related to the spine. These measures can also be useful in demonstrating improvements over time.