Smooth pursuit neck torsion test: Complete clinical guide

Key takeaways

The smooth pursuit neck torsion test (SPNT) compares eye tracking in a neutral position against tracking while the trunk is rotated 45 degrees.

Tracking that falls apart in torsion points to the neck as a source of dizziness rather than the inner ear.

No validated cutoff for the neutral-to-torsion difference exists yet, so published thresholds vary by study and by equipment.

Tjell and Rosenhall described the test in 1998, and later work supports its use after whiplash injury.

A positive result should push treatment toward cervical manual therapy, proprioceptive retraining, and gaze stability work.

Your patient still feels unsteady eight weeks after a rear-end collision. Their neck is stiff, the Dix-Hallpike is negative, and the vestibular screen explains none of it. The smooth pursuit neck torsion test was built for that moment.

The test compares how smoothly the eyes track a moving target in two positions. First the head sits neutral. Then the trunk rotates underneath a head that stays still. If tracking gets worse in torsion, the neck is a likely source of the dizziness.

Tjell and Rosenhall described the method in 1998. It has since spread through vestibular assessment protocols in physical therapy practices and chiropractic offices. The appeal is simple. It is quick, cheap, and needs nothing beyond a target to follow.

The SPNT separates neck-driven dizziness from vestibular dizziness

The smooth pursuit neck torsion test is a clinical oculomotor assessment with one job. It shows whether the cervical spine is contributing to a patient’s dizziness.

Standard smooth pursuit testing looks at the eye movement system on its own. The SPNT adds neck torsion as a variable you control. Rotate the trunk under a still head and cervical proprioceptive input changes, while the vestibular system stays exactly where it was.

That gives you a clean contrast. If the inner ear drives the dizziness, tracking holds steady wherever the trunk sits. If the neck drives it, tracking degrades or turns asymmetric as soon as torsion appears.

The difference decides the treatment plan. A positive SPNT points toward cervical management. A negative result in a patient who is still dizzy sends you back toward peripheral vestibular or central causes.

Why an injured neck can blur eye tracking

The upper cervical spine is dense with mechanoreceptors. Joint capsules, ligaments, and deep muscle spindles at C1 to C3 feed position information into the vestibular nuclei, the cerebellum, and the oculomotor pathways. The cervico-ocular reflex (COR) is one of the routes that signal takes to the eyes.

Normally you never notice any of it. Cervical input blends with vestibular and visual signals, and gaze stays stable while the body moves. After a whiplash injury, that input becomes distorted or lopsided.

The mismatch between the three systems is what the patient reports as dizziness, and it also shows up in the smoothness of their tracking. Torsion is how the test provokes it. Rotating the trunk 45 degrees stretches one side of the neck and shortens the other, which changes the signal arriving from the injured segments.

When the SPNT is worth running, and when it isn’t

Run the SPNT when cervical involvement is plausible, not on every dizzy patient who walks in. Five presentations put it firmly on the list:

• Neck pain with dizziness: symptoms that track with neck movement or with sustained neck postures
• Post-whiplash presentation: whiplash-associated disorder (WAD) grades I to III with dizziness, unsteadiness, or visual disturbance
• Unclear vestibular versus cervical cause: a negative Dix-Hallpike in a patient who still reports positional dizziness
• Post-concussion with neck injury: mild traumatic brain injury alongside cervical trauma, with oculomotor symptoms that persist
• Cervicogenic headache with balance symptoms: upper cervical headache plus unsteadiness or visual strain

Two situations argue against testing. Rule out upper cervical instability first, using the Sharp-Purser test or a vertebrobasilar screen, before you rotate anybody’s trunk. And where arm pain dominates the picture rather than dizziness, the arm squeeze test is a better place to start.

In practice, that decision belongs in the intake questionnaire rather than in the treatment room. Teams who run intake inside chiropractic practice software can flag these criteria there, so the call is already made when the patient sits down.

How to perform the smooth pursuit neck torsion test, step by step

You can run the test with or without instruments. VNG goggles or inertial head sensors return a numeric gain value for each condition. Without them you are judging tracking quality by eye, which still works, but the results are harder to compare across visits.

Either way, record the findings the same way every time. Digital assessment forms keep the three conditions in the same order in every patient record. That is what makes the second visit comparable to the first.

Before you start: A quick setup check

Most unreliable results come from the setup, not the test. Work through this before the first cycle:

• Screen for upper cervical instability and vertebrobasilar signs, and stop if either is unclear.
• Ask about sedatives, antiepileptic medication, alcohol, and poor sleep. All of them blunt smooth pursuit.
• Check the patient can sit unsupported for a few minutes without symptoms flaring.
• Fix the target distance, the speed, and the arc, then write those settings down for next time.
• Note any progressive lenses, and remove glasses if you are using goggles.
• Agree who rotates the trunk, you or a second examiner, before the patient is in position.

Phase 1: Baseline tracking with the head neutral

1. Seat the patient with their feet flat on the floor. Pelvis, trunk, and head all face forward in neutral alignment.
2. Place the target roughly 1 meter from the patient’s eyes, at eye level. A light bar, a pendulum, or your finger all work.
3. Ask the patient to follow the target with their eyes only, keeping the head still. Move it horizontally at about 0.3 to 0.5 Hz across a 40-degree arc.
4. Watch or record tracking in both directions for 5 to 10 cycles. With instruments, note the pursuit gain, which is eye velocity divided by target velocity.
5. Give the patient a 30-second rest before Phase 2.

Phase 2: Repeat with the trunk rotated 45 degrees

1. Keep the head in the same neutral forward position while you rotate the trunk 45 degrees to the left. The head stays still relative to the room, not the body.
2. Repeat the identical pursuit task, same target, same speed, same arc, for 5 to 10 cycles. Record gain in both directions.
3. Return the trunk to neutral and rest for 30 seconds.
4. Repeat the whole sequence with 45 degrees of right trunk rotation, and record gain again.
5. Compare all three conditions: neutral, left torsion, and right torsion.

Without instruments, you are grading tracking quality by observation. Look for catch-up saccades, for gaze that lags behind the target, and for tracking that worsens on one side of torsion but not the other. Structured clinical notes keep those three observations from collapsing into a single word.

Reading the result: What counts as positive

A positive SPNT means tracking got measurably worse once the trunk was rotated. In a healthy person, gain stays stable and symmetric across all three conditions, because intact cervical proprioception has nothing to complain about.

The figure you will see quoted most often is an 8% difference between neutral and torsion. Treat it as a rule of thumb rather than a diagnostic line.

Interacoustics, whose systems run much of this testing, states that no normative value for that difference has been established. Published studies use different cutoffs depending on their equipment and method.

So compare the patient against themselves. The direction of travel across sessions carries far more weight than whether one visit cleared a threshold. Storing each gain value in the patient record is what makes that trend visible later.

Figures quoted for that drop cluster around 8%, but no threshold has been validated, so keep the raw gain values in the note.

Run the numbers on one patient

Say your patient tracks at a gain of 0.92 in neutral and 0.78 in left torsion. The drop is 0.14, or roughly 15% of the neutral value. Right torsion comes back at 0.90, so the loss sits on one side only.

That pattern is more useful than a yes or no. It points you at the left side of the neck and gives manual therapy a starting point. It also hands you a number to re-test against in four weeks.

How strong is the evidence behind the SPNT?

Reasonable for whiplash-associated disorders, thinner for everyone else. The evidence base starts with Tjell and Rosenhall’s 1998 study. They found the test specific for cervical dizziness, with clear gain asymmetry in torsion compared to controls.

Accuracy figures move around between studies, because equipment, patient groups, and positivity thresholds all differ. Read the numbers below as orientation, not as a diagnostic rule.

Replication in larger and more varied groups is still limited. So the honest position is that the SPNT is a useful indicator with a defensible history, not a definitive test.

Four mistakes that make the result unreliable

The SPNT is simple to run and easy to run badly. These four errors account for most of the results that do not hold up on re-test:

1. Letting the head travel with the trunk. The head must stay fixed relative to the room. If it turns even slightly, you have removed the torsion you were testing.
2. Testing during an acute flare. Pain and muscle guarding degrade tracking on their own. Wait until the acute phase settles, or the number tells you about pain rather than proprioception.
3. Changing the target between conditions. A faster hand in torsion invalidates the comparison. Speed, distance, and arc all stay identical.
4. Reporting a single verdict. One word hides the side-to-side pattern, which is the part that guides treatment.

One more check is worth building in. If pursuit already looks poor in neutral, the problem may sit outside the neck altogether. A broader neurological eye exam comes before any cervical conclusion.

What a positive result changes in your treatment plan

A positive SPNT supports a cervicogenic diagnosis, it does not make one. It belongs alongside cervical range of motion testing, upper cervical provocation, the cervical flexion-rotation test, and a full vestibular screen. What it adds to that group is a functional marker tied directly to neck position.

Four combinations cover most of what you will see:

• Positive SPNT with a neck pain history: strong support for a cervical cause. Start manual therapy and proprioceptive retraining.
• Positive SPNT after whiplash: consistent with the published evidence. Document it carefully and add gaze stabilization to the program.
• Negative SPNT with ongoing dizziness: look again at peripheral vestibular causes such as BPPV or vestibular neuritis, and refer to audiology or ENT.
• Negative SPNT with neurological signs: escalate. Record your findings on a stroke scale such as the NIHSS score sheet and refer urgently.

The test earns its keep as an outcome measure too. Repeat it through a course of treatment and you can see whether cervical work is reducing gain asymmetry. That is harder to argue with than a symptom report alone.

Whiplash patients need one extra layer of caution

Whiplash muddles the picture because dizziness can come from vestibular concussion, from cervical proprioceptive disruption, or from both at once.

The follow-up WAD study found gain asymmetry significantly higher in whiplash patients than in healthy controls, which supports the cervical mechanism in this group.

Three points apply specifically to these patients:

• Timing changes the answer. Acute pain and guarding can produce asymmetry that has nothing to do with proprioception. Test once the guarding settles.
• A positive result rules nothing out. Post-concussive oculomotor problems often sit underneath, so keep screening for a central component.
• Serial testing is where it pays off. Asymmetry should shrink as cervical treatment progresses, and that trend is useful evidence for insurers and reports.

Rehab after a positive test: Retrain the neck, steady the gaze

Confirming a cervical contribution only helps if it changes the program. A positive SPNT should trigger cervical proprioceptive retraining paired with gaze stability work, ideally inside a structured plan with review points built in.

Cervical proprioceptive retraining

• Eye-head coordination drills: the patient holds gaze on a fixed target through slow, controlled head movement. This trains cervical position sense without overloading the vestibular system
• Laser pointer tracing: a head-mounted laser traces shapes on a wall, giving immediate feedback on head position accuracy
• Joint position error retraining: the patient closes their eyes, moves to a target position, returns to neutral, then tries to find it again. The error size quantifies the deficit and usually falls with practice

Gaze stabilization exercises

• VOR x1 viewing: the patient keeps text on a card clear while moving the head horizontally, which loads the vestibulo-ocular reflex in a controlled dose
• Smooth pursuit retraining: structured pursuit practice at rising speeds, starting in neutral and adding mild trunk rotation as tolerance improves
• Visual complexity progression: moving from a plain wall to busy patterns and screen-based tasks, so function returns in the environments the patient actually lives in

Progression logic borrows well from other areas of rehab. A return-to-running protocol works by setting objective milestones and loading against them, and vestibular work rewards the same discipline.

Set the functional goal, re-measure gain asymmetry at each stage, and progress on the measurement rather than on how the session felt.

Exercise-based rehabilitation has support behind it. A Cochrane review found vestibular rehabilitation improves gaze stability and balance in peripheral vestibular dysfunction.

Where the SPNT fits next to other cervical and vestibular tests

No single test locates the source of dizziness in a patient with neck pathology. Each one in the table below asks a different question, and the combination is what gives you an answer.

A workable cervicogenic dizziness battery pairs the SPNT with the cervical flexion-rotation test and joint position error testing. Add the Sharp-Purser test as a safety screen for anyone with upper cervical pain or an instability history. Keeping that battery in one comprehensive assessment template stops tests from quietly dropping off between clinicians.

How Pabau keeps SPNT results usable across sessions

Most practices write the SPNT into a free-text note. That works on the day. Six weeks later, nobody can find the neutral gain to compare against, and a serial outcome measure quietly stops being one.

Practice management software like Pabau handles it differently. You build the test once as three sets of form fields, one for neutral and one for each side of torsion.

Every clinician then fills the same fields in the same order. The values sit in the patient record beside the treatment notes rather than in a separate spreadsheet.

Because those numbers are stored as tracked measurements, you can pull a patient’s trend for a review appointment or a medicolegal report in seconds.

For a mixed vestibular and musculoskeletal caseload, that is the difference between owning an outcome measure and merely writing one down.

Keep every assessment score in one record

Pabau lets physical therapists and chiropractors capture assessment scores as structured fields, then compare them across sessions from the patient record. Follow-up plans, forms, and outcome data stay in one place, so review appointments start with the numbers already in front of you.

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Conclusion

Cervicogenic dizziness gets missed because it looks like everything else in the differential. The SPNT will not settle the question by itself. But it answers one thing no history-taking can, « Does changing neck position change how the eyes behave? »

So run it properly, record all three conditions, and repeat it at review. Across a course of treatment, the direction that gain asymmetry moves in will tell you more than any single visit did.

Just remember what the evidence supports, which is a strong indicator in a battery rather than a diagnosis on its own.

Book a demo to see how Pabau stores assessment scores against the patient record for physical therapy and chiropractic teams.

Continue your research

Building out your special test toolkit? Supine to long sit test walks through another position-dependent assessment, including how to interpret an inconsistent result.

Seeing arm symptoms alongside the neck pain? Hand nerve tests covers the screens that separate peripheral nerve involvement from cervical referral.

Need a structure for a full initial assessment? Comprehensive assessment template gives you a documented order for history, objective testing, and planning.

Setting up a practice that handles vestibular caseloads? Opening a physiotherapy clinic covers licensing, compliance, and clinical workflow design from the start.

Comparing systems for a physical therapy practice? Physiotherapy practice management software compares what different platforms do with notes, scheduling, and outcome data.

Frequently asked questions