Radicular pain, such as sciatica, is a prevalent condition treated by clinicians. It is a type of pain caused by inflammation and/or compression of the lumbosacral nerve roots, typically from L4 to S1 (1). This condition leads to an altered nerve function due to abnormal nerve excitability, which can manifest as paresthesia, pain, hyperalgesia, allodynia, hyperreflexia, and muscle spasms. Radicular pain usually presents in the buttock and radiates down the leg, often extending below the knee.

A recent study in primary care involving 609 patients revealed that 60% of individuals presenting with both back and leg pain were diagnosed with sciatica (2). Given its high prevalence and the significant pain and functional impairments associated with it, it is important for clinicians to accurately identify radicular pain and differentiate it from other conditions.

For example, lumbar radiculopathy also involves the nerve roots but results in a loss of nerve function. This condition is characterized by reduced impulse conduction, which can present as hypoesthesia, anesthesia, diminished reflexes, muscle weakness, or reduced sensation. It is important to note that patients may present with mixed symptoms of both conditions, sometimes referred to as painful radiculopathy (3).

Given the variability in presentation, it is often challenging to differentiate radicular pain from other causes of back and leg pain, such as sacroiliac joint dysfunction, hip pathology, or piriformis syndrome (4).

Risk Factors and Potential Causes of Radicular Pain

Understanding the risk factors and potential causes is essential for accurately diagnosing radicular pain.

While this list is not exhaustive, these factors are vital for a comprehensive assessment that includes both subjective and physical examinations:

Smoking, Obesity, Physical labor, Frequent bending, Prolonged sitting, Excessive walking, Psychological stress, Low job satisfaction, Vertebral disc lesions, Spinal stenosis, Spondylolisthesis

Diagnosing Sciatica

Diagnosing sciatica primarily involves clinical presentation, which combines the patient’s reported symptoms with findings from the physical examination. There is no single definitive test for sciatica, but the likelihood of diagnosis increases with a combination of positive findings (5). Imaging is generally not necessary unless there is suspicion of more serious pathology or if the patient does not respond to conservative management as expected (2). However, if the patient has already undergone imaging, it is beneficial to correlate the findings with the physical examination.

Key signs and symptoms of sciatica include:

– Predominant leg pain over back pain
– Pain location below the knee
– Dermatomal distribution
– Paresthesia and/or sensory loss in a spinal root pattern
– Myotomal weakness
– Reflex changes
– Leg pain exacerbated by coughing, sneezing, or deep breathing
– Gradual onset of symptoms

Findings on physical examination may include:

– Unilateral motor weakness, especially dorsiflexion weakness if L5 is affected, potentially leading to foot drop
– Absent tendon reflexes
– Positive Straight Leg Raise (SLR) test (a negative test reduces suspicion of sciatica)
– Positive cross-over test
– Increased finger-floor distance (>25cm)

It is important to rule out serious pathologies by screening for trauma, cancer, or severe infections. If the likelihood of serious pathology is low, clinicians should reconsider whether the primary diagnosis of radicular pain is accurate or if the pain originates from another source. Other conditions that can mimic radicular pain include peripheral artery disease, meralgia paresthetica, hip osteoarthritis, and piriformis syndrome (6).

If a patient presents with symptoms such as saddle anesthesia, bladder disturbances, loss of anal sphincter tone, decreased sexual function, or severe and progressive neurological deficits, cauda equina syndrome should be suspected, and the patient should be referred for immediate medical attention (7).

Below is a step-by-step guide to conducting a detailed subjective and objective examination for a patient presenting with radicular pain, such as sciatica.

Subjective Assessment for Radicular Pain: A Step-by-Step Guide

Step 1: Patient Interview and Rapport Building

1. Introduction and Rapport Building:
– Begin by introducing yourself and explaining the purpose of the examination. Establish a comfortable and trusting environment to encourage open communication.
– Engage in active listening and show empathy to build rapport with the patient.

2. Chief Complaints:
– Ask the patient to describe their primary concern or complaint in their own words.
– Use open-ended questions such as, “Can you tell me what brings you here today?” or “What is the main issue you are experiencing?”

Step 2: History of Present Illness (HPI)

1. Onset of Symptoms:
– Inquire about when the symptoms first started.
– Ask whether the onset was sudden or gradual, and if there was a specific event or injury that triggered the pain.
– Example questions: “When did you first notice the pain?” or “Did anything specific happen when the pain started?”

2. Location and Radiation of Pain:
– Ask the patient to describe the location of the pain and whether it radiates or spreads to other areas.
– Clarify whether the pain is localized to the lower back or radiates down the leg, and if so, which part of the leg (e.g., buttocks, thigh, calf, or foot).
– Example question: “Can you show me where you feel the pain, and does it move or spread anywhere else?”

3. Quality of Pain:
– Encourage the patient to describe the nature of their pain (e.g., sharp, dull, aching, burning, shooting, throbbing).
– Example question: “How would you describe the pain? Is it sharp, dull, or something else?”

4. Intensity of Pain:
– Use a pain scale to quantify the severity of the pain, asking the patient to rate their pain on a scale of 0 to 10, with 0 being no pain and 10 being the worst pain imaginable.
– Example question: “On a scale from 0 to 10, how would you rate your pain right now?”

5. Aggravating and Relieving Factors:
– Identify activities, movements, or positions that worsen or alleviate the pain.
– Example questions: “What makes the pain worse?” and “Is there anything that helps to relieve the pain?”

6. Duration and Frequency of Symptoms:
– Determine how long the pain lasts when it occurs and whether it is constant or intermittent.
– Ask about the frequency of episodes and any patterns or fluctuations in pain intensity.
– Example questions: “How long does the pain last when it comes on?” and “Does the pain come and go, or is it always there?”

7. Associated Symptoms:
– Ask if the patient experiences any other symptoms along with their back pain, such as numbness, tingling, muscle weakness, or changes in bowel or bladder function.
– Example questions: “Do you have any numbness or tingling in your legs or feet?” and “Have you noticed any changes in your ability to control your bowel or bladder?”

Mnemonic: LORDFICARA – Location, Onset, Radiating/Referred pain, Duration, Frequency, Intensity, Constancy/Character, Aggravating factors, Relieving factors, Associated signs/symptoms.

Step 3: Past Medical History

1. Previous Episodes:
– Inquire if the patient has had similar episodes of back pain or radiating leg pain in the past.
– Ask about any previous treatments, interventions, or surgeries related to the back or spine.
– Example questions: “Have you ever had back pain like this before?” and “Have you had any treatments or surgeries for your back?”

2. General Medical History:
– Ask about the patient’s overall health, including any chronic conditions, previous injuries, or relevant medical issues that may affect their current condition (e.g., diabetes, osteoporosis, arthritis).
– Example questions: “Do you have any other medical conditions?” and “Have you had any major injuries or surgeries?”

3. Medication and Allergies:
– Inquire about any medications the patient is currently taking, including over-the-counter drugs, supplements, and any known allergies.
– Example questions: “Are you taking any medications right now?” and “Do you have any allergies to medications?”

Step 4: Functional History

1. Impact on Daily Activities:
– Assess how the pain affects the patient’s ability to perform daily activities, such as walking, sitting, standing, lifting, or sleeping.
– Example questions: “How does your pain affect your daily life?” and “Are there any activities you find particularly difficult because of your pain?”

2. Work and Occupational History:
– Ask about the patient’s occupation, work environment, and any work-related activities that may contribute to their symptoms.
– Example questions: “What do you do for work?” and “Are there any tasks at work that make your pain worse?”

3. Exercise and Physical Activity:
– Inquire about the patient’s level of physical activity, exercise routine, and any recent changes in activity levels.
– Example questions: “Do you exercise regularly?” and “Have you made any changes to your physical activity recently?”

Step 5: Social and Psychological History

1. Social History:
– Gather information about the patient’s living situation, support system, and any social factors that may influence their health and well-being.
– Example questions: “Who do you live with?” and “Do you have friends or family who support you?”

2. Psychological and Emotional Factors:
– Explore any psychological or emotional factors that may affect the patient’s pain experience or recovery, such as stress, anxiety, depression, or coping mechanisms.
– Example questions: “How are you feeling emotionally about your pain?” and “Do you feel stressed or anxious about your condition?”

Step 6: Red Flag Screening

1. Screening for Red Flags:
– Perform a thorough screening for red flags that may indicate serious underlying conditions requiring immediate medical attention. Key red flags for low back pain include:
— Severe, unrelenting pain not relieved by rest or position changes.
— Unexplained weight loss or history of cancer.
— Bowel or bladder dysfunction (e.g., cauda equina syndrome).
— Significant trauma or osteoporosis (risk of fracture).
— Fever or systemic symptoms (potential infection).
– Example findings: “No red flags were identified during the examination.”

Step 7: Review of Systems

1. Comprehensive Review of Systems:
– Conduct a review of systems to identify any other symptoms or conditions that may be relevant to the patient’s current complaint.
– This includes cardiovascular, respiratory, gastrointestinal, genitourinary, neurological, and musculoskeletal systems

Example questions for cardiovascular system: “Have you experienced any chest pain or discomfort?”, “Do you have palpitations, or do you notice your heart racing or skipping beats?”, “Have you felt dizzy or fainted recently?”, “Do you experience swelling in your legs or ankles?”, “Have you noticed any shortness of breath, particularly when lying down or with exertion?”

• Relevance to Radicular Pain: Cardiovascular symptoms such as chest pain or palpitations may not be directly related to radicular pain but could indicate a concurrent cardiovascular condition. It’s important to rule out any cardiac cause for the pain, especially if the patient describes pain radiating to the arm, which could be confused with a cardiac issue.

Example questions for respiratory system: “Have you had any shortness of breath?”, “Do you have a cough? If so, is it dry or productive?”, “Have you noticed any wheezing?”, “Do you experience difficulty breathing during activity or at rest?”, “Have you had any recent respiratory infections?”

• Relevance to Radicular Pain: While respiratory symptoms may not be directly related to radicular pain, shortness of breath or a persistent cough could indicate other conditions, such as pulmonary embolism or pneumonia, which need to be ruled out, especially if the patient is postoperative or has been immobile.

Example questions for gastrointestinal system: “Do you have any nausea, vomiting, or changes in appetite?”, “Have you experienced any abdominal pain or discomfort?”, “Have you noticed any changes in your bowel habits, such as constipation or diarrhea?”, “Do you have any difficulty swallowing or experience heartburn?”, “Have you had any unexplained weight loss or gain?”

• Relevance to Radicular Pain: Gastrointestinal symptoms might not be directly related to radicular pain but could be side effects of pain medications, such as NSAIDs or opioids, commonly prescribed for managing radicular pain. Constipation is particularly common in patients taking opioid analgesics.

Example questions for genitourinary system: “Have you had any changes in your urinary habits, such as frequency, urgency, or difficulty urinating?”, “Do you experience any pain or burning when you urinate?”, “Have you noticed any blood in your urine?”, “Have you had any changes in sexual function?”, “Are you experiencing any incontinence?”

• Relevance to Radicular Pain: Changes in urinary or bowel habits, especially incontinence, could indicate cauda equina syndrome, a medical emergency often associated with severe radicular pain due to compression of the spinal nerves. Early identification is critical for appropriate management.

Example questions for neurological system: “Do you have any numbness or tingling in your legs or feet?”, “Have you experienced any weakness in your legs, feet, or toes?”, “Do you notice any changes in balance or coordination?”, “Have you had any unusual headaches or migraines?”, “Have you experienced any episodes of loss of consciousness, seizures, or blackouts?”

• Relevance to Radicular Pain: Neurological symptoms such as numbness, tingling, or weakness are directly relevant to radicular pain, which typically results from nerve root compression or inflammation. These questions help in localizing the affected nerve root, assessing the severity of nerve involvement, and differentiating the co-existing neurological symptoms due to conditions such as stroke.

Example questions for musculoskeletal system: “Do you have any pain, swelling or stiffness in your muscles, joints or back?”, “Can you dress yourself completely without any difficulty?”, “Can you walk up and down stairs without any difficulty?” (8)

• Relevance to Radicular Pain: A musculoskeletal review using the ‘GALS’ locomotor screen (8) can help to detect significant musculoskeletal abnormalities and differentiate radicular pain from musculoskeletal conditions such as myofascial pain, arthritis, or ligamentous injuries that might mimic or coexist with radicular symptoms.

Step 8: Patient Goals and Expectations

1. Understanding Patient Goals:
– Ask the patient about their goals and expectations for treatment, including what they hope to achieve through physical therapy.
– Example questions: “What are your goals for physical therapy?” and “What would you like to be able to do that you currently can’t because of your pain?”

Step 9: Closing the Subjective Assessment

1. Summarize Findings:
– Summarize the key points of the subjective assessment to ensure you have accurately understood the patient’s concerns and symptoms.
– Example statement: “To summarize, you are experiencing sharp pain in your lower back that radiates down your left leg, especially when you bend forward. You’ve had this pain for about two weeks, and it’s been getting worse.”

2. Explain Next Steps:
– Explain the next steps in the assessment process, including the physical examination and any additional tests or evaluations that may be necessary.
– Example statement: “Next, we’ll do a physical examination to better understand your symptoms and determine the best treatment plan for you.”

By following these steps, you will conduct a comprehensive and detailed subjective assessment that will provide valuable information for diagnosing and treating radiating low back pain.

Objective Assessment for Radicular Pain: A Step-by-Step Guide

The objective assessment should include a comprehensive neurological examination to evaluate nerve function for patients with radicular pain. This examination typically assesses light touch, reflexes, and motor strength. Additional tests such as pinprick or temperature assessments using hot/cold devices should also be considered.

Step 1: General Observation

1. Postural Assessment:
– Observe the patient’s posture while they are standing, sitting, and moving. Look for any abnormal curvatures of the spine (such as scoliosis, kyphosis, or lordosis), asymmetries in shoulder or pelvic height, and any signs of muscle wasting or hypertrophy.
– Example observations: “The patient demonstrates a forward head posture and increased lumbar lordosis.”

2. Gait Analysis:
– Observe the patient’s gait as they walk normally and on their toes and heels. Look for any abnormalities such as limping, altered stride length, antalgic gait (where the patient avoids putting weight on the painful side), or difficulty with specific movements (e.g., toe walking or heel walking).
– Example observations: “The patient exhibits a shortened stride length on the left side and avoids full weight-bearing on the left leg.”

3. GALS Screening (8):
– Alternatively, you can use the GALS (Gait, Arms, Legs, Spine) screening examination to inspect for joint swelling, abnormal posture, and joint movement (8). It takes about 1-2 minutes to complete the GALS screening examination. If the GALS screen identifies any abnormalities, a more detailed examination of the affected area is necessary. The GALS screen is designed to flag potential issues but does not diagnose specific problems. Typically, the examination is conducted in a sequence that completes standing assessments before moving on to those that require the patient to lie down, but the order can be adjusted as needed. Please read more about the GALS screen here.

Step 2: Range of Motion (ROM) Testing

1. Active Range of Motion (AROM):
– Instruct the patient to perform active movements of the lumbar spine, including flexion, extension, lateral flexion (side bending), and rotation. Note any restrictions, pain, or abnormal movements during these motions.
– Example findings: “The patient reports increased pain radiating down the left leg during lumbar flexion, with a limited range of motion in extension and lateral flexion to the right.”

2. Passive Range of Motion (PROM):
– Assess the patient’s passive range of motion in the lower limbs, specifically focusing on the hip, knee, and ankle joints. This helps identify any joint stiffness, capsular restrictions, or pain that might contribute to the symptoms.
– Example findings: “Passive hip flexion is restricted on the left side with pain radiating to the posterior thigh.”

Step 3: Neurological Examination

1. Sensory Testing:
– Perform light touch and pinprick testing to assess dermatomal distribution of sensory changes. This helps to identify areas of hypoesthesia (reduced sensation), hyperesthesia (increased sensation), or anesthesia (absence of sensation).
– Example findings: “The patient reports decreased sensation to light touch over the L5 dermatome on the left side.”

2. Motor Strength Testing:
– Conduct manual muscle testing for key muscle groups innervated by the lumbar and sacral nerve roots (e.g., hip flexors, knee extensors, ankle dorsiflexors, and plantar flexors). Grade the strength on a scale from 0 (no contraction) to 5 (normal strength).
– Example findings: “There is a 4/5 strength in the left ankle dorsiflexors, indicating mild weakness.”

3. Reflex Testing:
– Test deep tendon reflexes, including the patellar (L3-L4) and Achilles (S1-S2) reflexes. Look for diminished or absent reflexes, which could indicate nerve root compression or radiculopathy.
– Example findings: “The left Achilles reflex is diminished compared to the right.”

4. Neurodynamic Testing:
– Perform special neurodynamic tests such as the Straight Leg Raise (SLR) test, Slump test, and Femoral Nerve Stretch test to assess nerve root tension and irritability.
– Example findings: “The Straight Leg Raise test is positive at 45 degrees on the left, reproducing the patient’s radiating pain down the leg.”

Step 4: Resisted Isometric Testing (for differential diagnosis, if necessary)

1. Perform isometric testing for key muscle groups innervated by the lumbar and sacral nerve roots, including the hip flexors, knee extensors, ankle dorsiflexors, and plantar flexors. Ask the patient to resist applied force without moving the joint to assess both strength and pain response.

2. Grade the findings based on the strength of the contraction and the presence of pain, using standard descriptors like “strong and pain-free,” “weak and pain-free,” “strong and painful,” or “weak and painful.”

3. Example Findings: “Resisted isometric testing for the muscle groups innervated by the lumber and sacral nerve roots is strong and pain-free, suggesting no involvement of the muscles or tendons in this area.”

Step 5: Special Tests

1. Lumbar Spine Special Tests:
– Perform special tests for the lumbar spine to help differentiate between different types of low back pain and confirm a diagnosis. Key tests include:
– Quadrant Test: Assesses for lumbar facet joint dysfunction, with a sensitivity of 50-70% (9) and specificity of 67.3% (10).
– Passive Lumbar Extension Test: Detects lumbar instability, with a sensitivity of 43-84% (11, 12) and specificity of 86-90% (11, 12).
– FABER Test: Evaluates for hip or sacroiliac joint pathology, with a sensitivity of 72-89% (13, 14) and specificity of 67% (14).
– Example findings: “The Quadrant Test reproduces the patient’s low back pain without leg symptoms, indicating possible facet joint involvement.”

2. Peripheral Joint Screening:
– Assess neighboring joints, such as the hip and knee, for any signs of referred pain or secondary issues that may contribute to the patient’s symptoms.
– Example findings: “The hip joint shows full range of motion without pain, ruling out hip pathology as a source of referred pain.”

Step 6: Palpation

1. Soft Tissue Palpation:
– Palpate the muscles, tendons, and ligaments of the lumbar spine, gluteal region, and lower extremities to identify areas of tenderness, muscle spasms, or trigger points.
– Example findings: “Tenderness is noted in the left piriformis muscle, with palpable muscle spasm in the lumbar paraspinals.”

2. Joint Palpation and Mobility Assessment:
– Palpate the lumbar spine’s spinous and transverse processes to identify any tenderness, alignment abnormalities, or step-offs that may indicate a spondylolisthesis or fracture.
– Assess joint mobility of the lumbar spine and sacroiliac joints using passive accessory motion testing (e.g., posterior-anterior mobilization).
– Example findings: “Hypomobility is noted at the L4-L5 segment with increased tenderness upon palpation.”

Step 7: Functional Assessment

1. Functional Movement Testing:
– Evaluate the patient’s ability to perform functional movements such as squatting, lifting, bending, or single-leg balance. Observe for any compensatory movements, difficulty, or pain.
– Example findings: “The patient demonstrates difficulty and increased pain when performing a single-leg squat on the left side.”

2. Functional Outcome Measures:
– Utilize standardized outcome measures to objectively assess the patient’s functional status and quantify their level of disability. Common tools include the Oswestry Disability Index (ODI), Roland-Morris Disability Questionnaire (RMDQ), and the Fear-Avoidance Beliefs Questionnaire (FABQ).
– Example findings: “The patient scores 40% on the Oswestry Disability Index, indicating moderate disability due to back pain.”

Step 8: Summary and Clinical Impression

1. Summarize Findings:
– Compile and summarize the key findings from the objective examination, highlighting any significant deficits, positive tests, or areas of concern.
– Example statement: “The objective examination reveals a positive Straight Leg Raise test on the left, diminished Achilles reflex, and weakness in the left ankle dorsiflexors, consistent with a potential L5-S1 radiculopathy.”

2. Formulate a Clinical Impression or Working Diagnosis:
– Based on the collected data, formulate a clinical impression or working diagnosis that will guide the development of a treatment plan.
– Example statement: “The findings indicate radicular pain, likely resulting from a lumbar disc herniation at the L5-S1 level, with associated nerve root compression suggestive of L5-S1 radiculopathy.”

By following this step-by-step guide, you will conduct a comprehensive and thorough objective assessment for a patient presenting with radiating low back pain. This approach ensures that all relevant components are assessed, providing valuable information for accurate diagnosis and effective treatment planning.

Additional Considerations

Electrodiagnostic Testing: While not typically required for initial assessment, electrodiagnostic studies like electromyography (EMG) and nerve conduction studies (NCS) can be valuable in ambiguous cases or when surgical intervention is being considered.

Advanced Imaging: In certain cases, MRI or CT scans may be warranted to visualize soft tissue structures, nerve roots, or potential compressive lesions more clearly, particularly when surgical intervention is a consideration.

Reference:

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