SIRVA vs. Cervical Radiculopathy: How Can Physicians Distinguish Them?
Shoulder pain following vaccination may originate from the shoulder itself, the cervical spine, or a peripheral nerve. Distinguishing these conditions is essential for establishing the correct diagnosis and determining whether vaccination caused the symptoms.
One of the challenges in evaluating suspected Shoulder Injury Related to Vaccine Administration (SIRVA) is determining whether the patient's symptoms originate from the shoulder or another anatomical structure.
A patient may develop shoulder pain after vaccination and subsequently report pain radiating down the arm, weakness, numbness, or tingling. Although these symptoms may raise concern for SIRVA, they can also occur with cervical radiculopathy, peripheral nerve injury, and other neurologic conditions.
The distinction is important because cervical radiculopathy and injection-related shoulder injuries have different mechanisms, examination findings, and implications for medical causation.
Shoulder pain beginning after vaccination does not necessarily mean that the shoulder joint or surrounding tissues are the source of the symptoms.
Key Takeaways
SIRVA and cervical radiculopathy can produce overlapping symptoms, including shoulder pain, arm pain, and perceived weakness.
Pain radiating below the elbow, particularly with numbness or tingling, raises concern for cervical radiculopathy, although these findings are not diagnostic by themselves.
Restriction of passive shoulder motion favors intrinsic shoulder pathology, particularly adhesive capsulitis or glenohumeral joint disease.
Neurologic examination is essential. Dermatomal sensory abnormalities, myotomal weakness, and altered reflexes may support cervical nerve root involvement.
Cervical MRI abnormalities are common and may be incidental. Imaging findings must correlate with the patient's symptoms and examination.
Direct injection-related peripheral nerve injury is distinct from cervical radiculopathy. These conditions should not be considered interchangeable.
The two conditions can coexist. Identifying cervical pathology does not automatically exclude a separate vaccine-related shoulder injury.
What Is Cervical Radiculopathy?
Cervical radiculopathy occurs when a cervical nerve root becomes irritated or compressed, commonly due to degenerative changes involving the cervical spine.
Potential causes include:
Cervical disc herniation
Foraminal stenosis
Cervical spondylosis
Osteophyte formation
Other conditions affecting the cervical nerve roots
Symptoms may include neck pain, shoulder pain, radiating arm pain, numbness, tingling, or weakness.
Importantly, cervical radiculopathy does not always produce prominent neck pain. Some patients primarily experience pain in the shoulder or upper arm, which can make the condition difficult to distinguish from intrinsic shoulder pathology.
The distribution of symptoms depends partly on the affected nerve root. For example, C5 radiculopathy may produce pain involving the lateral shoulder and weakness with shoulder abduction, findings that can resemble rotator cuff pathology.
C6 or C7 radiculopathy may produce pain extending farther down the arm, often accompanied by sensory changes or weakness involving the elbow, wrist, or hand. However, symptom distributions are variable, and not every patient follows a classic dermatomal pattern.
How Does Cervical Radiculopathy Differ From SIRVA?
SIRVA is generally associated with injury or inflammation involving structures in or around the shoulder following vaccine administration.
The proposed mechanism frequently involves improper injection placement, particularly an injection administered too high or too deep within the deltoid region. Potentially affected structures include the subacromial-subdeltoid bursa, rotator cuff tendons, and other periarticular tissues.
Cervical radiculopathy, in contrast, originates from a cervical nerve root. These different anatomical sources may produce similar symptoms, but they often demonstrate different clinical patterns.
Clinical feature | Intrinsic shoulder pathology associated with SIRVA | Cervical radiculopathy |
Primary pain location | Shoulder, often lateral or anterior | Neck, shoulder, scapula, or arm |
Pain below elbow | Less typical, but possible | More suggestive |
Numbness or tingling | Uncommon with isolated bursitis or tendinopathy | May occur |
Passive shoulder motion | May be painful or restricted | Often preserved |
Neck movement | Usually does not reproduce primary shoulder pain | May reproduce radiating symptoms |
Reflex abnormalities | Not expected with isolated shoulder pathology | May be present |
Myotomal weakness | Not typical | May be present |
Shoulder MRI | May demonstrate local pathology | May be normal or show incidental findings |
Cervical MRI | May show incidental degeneration | May show concordant nerve root compression |
These are general patterns rather than absolute diagnostic criteria. A patient may have both shoulder disease and cervical radiculopathy, and some findings overlap substantially.
1. Does Pain Radiating Down the Arm Suggest Cervical Radiculopathy?
The location and distribution of pain provide important diagnostic information.
Intrinsic shoulder disorders commonly produce pain involving the lateral shoulder and upper arm. For example, subacromial bursitis or rotator cuff tendinopathy may cause pain extending toward the deltoid insertion.
However, pain extending below the elbow, particularly when associated with numbness, tingling, or electric-like sensations, raises greater concern for a neurologic source. Cervical radiculopathy may produce pain radiating from the neck or scapular region into the arm, forearm, or hand.
The pattern may correspond to a particular nerve root, although considerable overlap exists. It is important to recognize that pain distribution alone cannot reliably distinguish these conditions.
Some patients with intrinsic shoulder pathology report pain extending distally, while patients with cervical radiculopathy may experience predominantly shoulder pain. The distribution should therefore be interpreted alongside the neurologic and musculoskeletal examinations.
2. What Does the Physical Examination Reveal?
A comprehensive examination should include both the shoulder and cervical spine. Focusing exclusively on the shoulder may overlook cervical radiculopathy, while examining only the cervical spine may miss a concurrent shoulder injury.
Shoulder examination
The shoulder examination should assess:
Active and passive range of motion
Pain with resisted rotator cuff testing
Rotator cuff strength
Localized tenderness
Glenohumeral capsular restriction
Painful arc and other provocative maneuvers
Restriction of both active and passive glenohumeral motion may support adhesive capsulitis or other intrinsic joint pathology. In contrast, preserved passive motion with weakness may raise concern for rotator cuff injury or neurologic dysfunction.
However, pain-related inhibition can produce apparent weakness without a structural tendon tear or neurologic deficit.
Cervical and neurologic examination
The cervical examination should assess:
Cervical range of motion
Reproduction of arm symptoms with neck movement
Upper extremity sensation
Myotomal strength
Deep tendon reflexes
Provocative maneuvers for cervical radiculopathy
Objective neurologic abnormalities may be particularly helpful. For example, weakness in a myotomal distribution accompanied by sensory changes and an altered reflex provides stronger support for cervical nerve root dysfunction than shoulder pain alone.
3. Which Physical Examination Tests Help Identify Cervical Radiculopathy?
Several examination maneuvers have been studied for their diagnostic utility.
Spurling Test
The Spurling test is performed by positioning the cervical spine to narrow the neural foramen, typically through extension, lateral flexion, and carefully applied axial compression. Reproduction of the patient's characteristic radiating arm symptoms is considered a positive finding.
Studies generally suggest that the Spurling test has relatively high specificity but variable sensitivity. Therefore, a positive test may increase suspicion for cervical radiculopathy, while a negative test does not reliably exclude it.
Upper Limb Tension Test
Upper limb neurodynamic testing places mechanical tension on neural structures of the upper extremity. Reproduction of characteristic symptoms may support neural mechanosensitivity.
Some studies have reported relatively high sensitivity for selected upper limb tension tests, although specificity is limited and diagnostic accuracy varies by technique and population. A negative test may be useful in reducing suspicion for cervical radiculopathy when considered with other findings.
Cervical Distraction Test
The cervical distraction test evaluates whether gentle traction reduces radiating arm symptoms. Symptom relief may support a cervical source of pain. However, the test is not sufficiently accurate to establish a diagnosis independently.
Shoulder Abduction Relief Sign
Some patients with cervical radiculopathy experience relief when placing the symptomatic hand on top of the head. This finding may support nerve root involvement, although sensitivity is variable.
Combining Examination Findings
Wainner and colleagues evaluated a cluster of findings that included:
Positive Spurling test
Positive cervical distraction test
Positive upper limb tension test
Cervical rotation less than 60 degrees toward the symptomatic side
The combination of several positive findings increased the likelihood of cervical radiculopathy in the studied population. However, the accuracy of this cluster should not be assumed to apply identically to every patient, particularly those with concurrent shoulder pathology.
No single examination maneuver reliably establishes or excludes cervical radiculopathy.
4. Can Shoulder Weakness Help Distinguish the Two Conditions?
Weakness may occur with both intrinsic shoulder pathology and cervical radiculopathy. The pattern of weakness is often more informative than its presence alone. Rotator cuff tears may produce weakness with shoulder abduction or external rotation.
C5 radiculopathy may also produce weakness with shoulder abduction, while C6 involvement may affect elbow flexion or wrist extension.
This creates substantial overlap. However, weakness involving several muscles supplied by the same nerve root but different peripheral nerves may support radiculopathy.
For example, weakness involving shoulder abduction and elbow flexion, accompanied by an altered biceps reflex, may raise concern for C5 or C6 nerve root involvement. In contrast, isolated painful weakness during resisted shoulder abduction with otherwise normal neurologic findings may be more consistent with intrinsic shoulder pathology. Pain-related inhibition should also be considered, as it can mimic true weakness.
5. What Role Does Cervical MRI Play?
Cervical MRI may identify disc herniation, foraminal stenosis, and other structural abnormalities capable of affecting nerve roots. However, cervical degenerative changes are common, including in individuals without symptoms.
Boden and colleagues demonstrated a substantial prevalence of cervical MRI abnormalities among asymptomatic volunteers.
Therefore, identifying a disc protrusion or foraminal narrowing does not independently establish that the abnormality is responsible for the patient's shoulder or arm pain.
The imaging findings should correspond to the clinical presentation. For example, a patient with right-sided C6-pattern symptoms, concordant weakness, and right C5–C6 foraminal stenosis presents a more coherent diagnostic picture than a patient with nonspecific shoulder pain and unrelated degenerative changes at multiple cervical levels.
The same principle applies to shoulder MRI. Rotator cuff tears, tendinopathy, and degenerative abnormalities may be present without symptoms.
Imaging is most useful when it confirms a diagnosis already supported by the history and physical examination.
6. When Is Electrodiagnostic Testing Helpful?
Electrodiagnostic testing, including nerve conduction studies and needle electromyography (EMG), may be useful when the clinical presentation is unclear.
Potential indications include:
Persistent weakness
Unexplained sensory abnormalities
Suspected cervical radiculopathy
Suspected peripheral nerve injury
Conflicting cervical and shoulder imaging findings
Concern for brachial plexopathy
Needle EMG may demonstrate abnormalities involving muscles supplied by a particular cervical nerve root. The examination can also help distinguish radiculopathy from certain peripheral nerve injuries. For example, an isolated axillary neuropathy may produce deltoid weakness and sensory changes over the lateral shoulder.
In contrast, cervical radiculopathy may involve several muscles supplied by the same nerve root through different peripheral nerves.
However, EMG has limitations. A normal study does not necessarily exclude cervical radiculopathy, particularly when symptoms are predominantly sensory or the study is performed before denervation changes become detectable. Electrodiagnostic findings should therefore be interpreted in conjunction with the clinical examination and imaging.
7. Could Vaccination Cause a Peripheral Nerve Injury Instead of SIRVA?
Yes. Direct injection-related peripheral nerve injury is a separate consideration. Improper needle placement may injure a peripheral nerve near the injection site. Potentially affected nerves include the axillary nerve and, depending on injection location, other adjacent neural structures.
A direct nerve injury may produce:
Immediate sharp or electric-like pain
Numbness or tingling
Focal weakness
Sensory changes corresponding to the affected nerve
Persistent neurologic deficits in more significant injuries
These findings differ from isolated subacromial bursitis or rotator cuff tendinopathy.
Importantly, direct peripheral nerve injury should not be confused with cervical radiculopathy.
The cervical nerve roots are anatomically remote from the deltoid injection site.
Therefore, a routine deltoid vaccination does not provide a plausible direct mechanical mechanism for injury to a cervical nerve root. The 2024 National Academies review concluded that direct injection can cause certain peripheral nerve injuries, including axillary and radial nerve injury.
This supports the importance of identifying the specific neurological structure involved rather than broadly attributing all post-vaccination arm symptoms to SIRVA.
8. Can SIRVA and Cervical Radiculopathy Occur Together?
Yes. Shoulder pathology and cervical degenerative disease frequently coexist, particularly in middle-aged and older adults.
A patient may have preexisting cervical foraminal stenosis and subsequently develop an injection-related inflammatory shoulder condition. Alternatively, a patient may have asymptomatic rotator cuff abnormalities and develop cervical radiculopathy after vaccination for unrelated reasons.
The presence of one diagnosis does not automatically exclude the other. This is particularly important when MRI demonstrates abnormalities in both the cervical spine and shoulder.
The physician must determine which findings are clinically relevant and whether one or more conditions explain the patient's symptoms. In some cases, both conditions contribute to the clinical presentation.
9. Why Does This Distinction Matter for SIRVA Causation?
Consider two hypothetical cases.
Scenario 1: Findings favor cervical radiculopathy
A 62-year-old patient develops shoulder pain approximately two weeks after vaccination.
The pain extends into the forearm and thumb and is accompanied by intermittent tingling.
Shoulder examination demonstrates preserved passive range of motion without significant pain during resisted rotator cuff testing.
Cervical extension and rotation reproduce the radiating symptoms. Examination demonstrates reduced brachioradialis reflex and weakness with wrist extension.
Cervical MRI reveals right-sided C5–C6 foraminal stenosis consistent with the clinical findings.
In this scenario, the history, examination, and imaging support cervical radiculopathy as a more convincing explanation than an injection-related shoulder injury. Although symptoms began after vaccination, the temporal relationship alone does not establish causation.
Scenario 2: Findings favor an injection-related shoulder injury
A 48-year-old patient with no prior shoulder symptoms experiences immediate deep shoulder pain following a vaccination reportedly administered unusually high in the deltoid.
Over the following 24 hours, the patient develops persistent shoulder pain and restricted motion.
Physical examination demonstrates painful restriction of shoulder movement without dermatomal sensory loss, reflex abnormalities, or myotomal weakness. Cervical examination does not reproduce the symptoms.
MRI demonstrates inflammatory changes involving the subacromial-subdeltoid bursa.
In this scenario, the clinical presentation is more consistent with an intrinsic shoulder injury.
The immediate symptom onset, plausible injection location, objective shoulder findings, and absence of a more convincing cervical explanation provide support for a vaccine-related injury.
Neither scenario establishes causation through a single finding. Rather, the conclusions depend on the consistency of the overall clinical evidence.
10. What Should Physicians Document When Evaluating Suspected SIRVA?
When evaluating suspected SIRVA, particularly when patients report radiating arm pain or neurologic symptoms, the medical record should address both shoulder and cervical sources.
Important documentation includes:
Symptom onset: Timing relative to vaccination, initial pain location, and subsequent progression.
Pain distribution: Shoulder, scapular region, arm, forearm, or hand.
Neurologic symptoms: Numbness, tingling, weakness, or altered sensation.
Shoulder examination: Active and passive motion, strength, tenderness, and provocative testing.
Cervical examination: Range of motion, symptom reproduction, and relevant provocative maneuvers.
Neurologic examination: Sensation, reflexes, and myotomal strength.
Imaging: Shoulder and cervical findings, interpreted in the context of the clinical presentation.
Electrodiagnostic studies: When needed to distinguish radiculopathy, plexopathy, or peripheral nerve injury.
Preexisting conditions: Prior shoulder or cervical symptoms, diagnoses, imaging, and treatment.
This information helps establish both the diagnosis and whether the clinical findings support a relationship to vaccination.
The Bottom Line
So, how can physicians distinguish SIRVA from cervical radiculopathy?
The distinction depends on identifying the anatomical source of the symptoms through a careful history, shoulder and cervical examination, neurologic assessment, and appropriately selected diagnostic studies.
SIRVA generally involves injury or inflammation affecting structures in or around the shoulder, whereas cervical radiculopathy originates from a cervical nerve root.
Pain radiating below the elbow, neurologic symptoms, myotomal weakness, and altered reflexes may favor cervical radiculopathy.
Painful or restricted shoulder motion, localized shoulder findings, and imaging demonstrating anatomically consistent inflammation may favor intrinsic shoulder pathology. However, the conditions can coexist, and neither shoulder nor cervical MRI abnormalities independently establish the cause of symptoms.
Ultimately, the presence of shoulder pain after vaccination does not establish that the shoulder is the source of the pain—or that vaccination caused the underlying condition.
A medically defensible SIRVA causation opinion should identify the specific diagnosis, evaluate competing explanations, and determine whether the proposed injection-related mechanism is consistent with the available evidence.
References
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Wainner RS, Fritz JM, Irrgang JJ, Boninger ML, Delitto A, Allison S. Reliability and diagnostic accuracy of the clinical examination and patient self-report measures for cervical radiculopathy. Spine (Phila Pa 1976). 2003;28(1):52–62.
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Katsuura Y, Bruce J, Taylor S, Gullota L, Kim HJ. Overlapping, masquerading, and causative cervical spine and shoulder pathology: a systematic review. Global Spine J. 2020;10(2):195–208.
Childress MA, Becker BA. Nonoperative management of cervical radiculopathy. Am Fam Physician. 2016;93(9):746–754.
National Academies of Sciences, Engineering, and Medicine. Evidence Review of the Adverse Effects of COVID-19 Vaccination and Intramuscular Vaccine Administration. Washington, DC: National Academies Press; 2024. Chapter 10: Shoulder Injuries and Vaccines. https://doi.org/10.17226/27746
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About the Author
Walter I. Sussman, DO, is a board-certified physician in Sports Medicine and Physical Medicine & Rehabilitation with expertise in musculoskeletal ultrasound, shoulder pathology, and the evaluation of Shoulder Injury Related to Vaccine Administration (SIRVA).
This article is intended for educational purposes and does not constitute a medical opinion regarding any individual case. Assessment of diagnosis and causation requires review of the specific medical history, clinical findings, imaging, and circumstances involved.
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