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Home , Neurological examination

Distinguishing neurological from non-organic conditions Vague symptom complexes can be difficult to manage in a neurological context.

J M N Enslin, MB ChB, BPhysT Registrar, Division of Neurosurgery, Groote Schuur Hospital and Red Cross War Memorial Children’s Hospital, Cape Town Nico Enslin is a physiotherapist and medical doctor. He qualified at the University of Pretoria. He is currently a Neurosurgery Registrar at Groote Schuur Hospital and Red Cross War Memorial Children’s Hospital, Cape Town

A Taylor, MB BCh, FCS (SA), MMed, MSc (Paris Sud) Associate Professor and Consultant Neurosurgeon, Division of Neurosurgery, Groote Schuur Hospital, Cape Town Professor Taylor has an interest in neurovascular disease.

Correspondence to: J M N Enslin ([email protected])

Although neurological conditions may Special investigations and radiological • associated with nausea and present with specific clinical patterns, imaging are costly and time consuming. It vomiting – in the absence of previous practitioners often encounter patients with is not just about time and money though. diagnosis of migraine vague symptom complexes. In this context, Sometimes well-intentioned investigations • headache that is position dependent a common trap is to assume that the reveal incidental lesions that have nothing (worse on bending forward and lying condition is non-organic in origin, thereby to do with the patient’s symptoms but now down) possibly missing an important diagnosis. It become a new focus for concern. In this • headache that is worse on straining is easy to be frustrated with such a patient – article the authors highlight features that (Valsalva and coughing) should they simply be reassured, or should will aid the clinician in decisions on referral • chronic in children younger one investigate further? as well as further investigations, focusing on than 10 years. symptom complexes that occur commonly One way to deal with this is to direct in general practice. In the presence of any of the abovementioned history taking and examination towards signs radiological investigation is required the features that are likely to indicate to rule out brain tumours, hydrocephalus something serious. If no sinister features A common trap is to and cerebral haemorrhage or subarachnoid are revealed, it may be best to delay assume that the condition haemorrhage. Although normal fundoscopy further investigation in favour of repeat is non-organic in origin, is often reassuring, it does not exclude an examination should symptoms remain or cause for headache. progress. Various authors have suggested thereby possibly missing strategies to differentiate between organic an important diagnosis. It is extremely difficult to rule out psychi- and non-organic causes of neurological atric or non-organic causes of headaches. symptoms and signs. Fahn and Williams Therefore, the role of a careful history and proposed a set of diagnostic criteria for Headache insight into the patient’s family, job and per- psychogenic movement disorders in 1988, According to the WHO fact sheet on sonal satisfaction cannot be over-empha- which may be applied to a wide spectrum Headache Disorders (2011),[3] an estimated sised. of diseases, including key features such as 47% of adults worldwide will have headaches an abrupt onset, inconsistent features, with at least once a year. This makes headache Dizziness false weakness and sensory abnormalities, one of the most common conditions that Dizziness is a term used by patients to as well as distractibility.[1] a family practitioner encounters in daily describe a whole range of symptoms – practice. ‘Do I have a brain tumour doctor?’, anything from feeling faint, fainting spells Psychogenic neurological signs or conversion is a question that the headache patient or light headedness to losing balance and disorder generally result from a disturbance often asks. Fortunately, the correct answer vertigo. A detailed history is important. in higher cortical structures that interpret or is almost always ‘No, you don’t’, but the Dizziness is rarely caused by a life- produce neurological messages. Patients with pitfall is that the patient with an intracranial threatening neurological condition, but it these conditions therefore experience, but tumour may have nonspecific headache as may be a sign of neurological disease. do not have control over, their signs and a presenting feature, as may many other symptoms. The term malingering refers to organic diseases. Features suggestive of a Loss of balance (disequilibrium) may be a the deliberate feigning of signs or symptoms, serious underlying cause include: symptom of cerebellar ataxia or inner ear usually for secondary gain.[2] For the purposes • any decrease in level of diseases such as Meniere’s disease, otitis of this article, non-organic refers to both • sudden onset of severe headaches media or vestibulitis. Vertigo (the of malingering and conversion disorder, and associated with neck stiffness motion or spinning) may be associated with distinguishes them from organic pathology. • headache associated with any new cerebello-pontine lesions as well as cerebellar Remember that paraneoplastic syndromes neurological deficit or papilloedema lesions. If any of these symptoms are typically present with bizarre symptoms and • early morning headache that improves associated with cerebellar signs or weakness, signs. during the day further investigation is warranted.

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Medication and cardiac as well as anxiety disorders are more common causes of Table 1. Upper versus lower weakness dizziness and fainting. Therefore, one weakness weakness should always start by ruling these out. Muscle weakness Muscle weakness Check patient history, blood Less atrophy of muscles (may be disuse) Atrophy of muscles pressure, ECG, and psychological history Increased tone, Low muscle tone thoroughly. Increased deep tendon Diminished or absent deep tendon reflexes The presence of the following in the history No Fasciculation should alert to the potential for neurological Hemiplegic, quadriplegic or paraplegic Specific distribution of weakness, i.e. proximal causes of the dizziness: distribution of weakness; upper limb weakness in muscle dystrophy v. distal weakness • recent trauma or extensors and lower limb flexors in peripheral neuropathies predominantly affected • leakage of fluid (CSF) from the ear or nose Decreased or absent abdominal reflexes Abdominal reflexes present • poor co-ordination of gait or fine motor Extensor plantar (Babinski sign) Flexing plantar reflexes activity (such as buttoning a shirt) Clonus at ankle and patella Raised creatine kinase level in muscular • associated headaches or vomiting diseases • transient blindness or blind spots in Flexor withdrawal reflex Abnormal electromyograph visual field • problems with swallowing or speech • association with or absences. A Cannot lift left leg

A thorough neurological examination should always be part of the workup of any patient complaining of dizziness. Also check eye-sight in the elderly, the neck for presence of bruits and the external ear canal for the presence of wax build-up.

Weakness/lameness Weakness of a limb or of all the limbs B is a frequent claim in insurance and workman’s compensation claims. This is probably one of the most readily manipulated features of malingering behaviour. There are, however, some tricks that the astute physician can use to Downward pressure on right leg counter these ‘acts’. With few exceptions, motor weakness fits into either an upper motor neuron or lower motor neuron pattern (Table 1).[4] There are, however, Fig. 1. Hoover’s sign. some exceptions such as motor neuron disease, which may have both upper and on the right, but intact head turning and sensory abnormalities tend to follow certain lower motor neuron signs. flexion to the left, should cause suspicion. rules: Testing limb muscles on the left in standing • dermatomal pattern in radicular Weakness that does not fit into any of or sitting on unsteady surfaces also shows syndromes these categories is unlikely to be organic intact postural reflexes that utilises muscles • glove and stocking distal sensory loss in in origin. Remember to check deep of the trunk and contralateral limbs to peripheral neuropathies, such as diabetes tendon reflexes in different positions, stabilise, hereby allowing the examiner mellitus and alcohol neuropathy as they tend to be constant if disease is to observe discrepancies in the formal • spinal injury or compression causes a present. Another useful test to differentiate testing and these ‘catch out’ tests. The definite sensory level organic from non-organic weakness is Hoover sign[5] is designed to elicit this • central cord syndrome leads to a sus- the sternocleidomastoid muscle group phenomenon (Fig. 1). pended sensory level (‘cape distribution’) test. Anatomically, the muscle on the • herpes zoster has typical vesicular skin right of the neck causes rotation to the Sensory changes changes and follows a clear dermatomal contralateral side and flexion, therefore When doing a sensory examination it is very pattern that does not cross the midline turning the head to the left tests the muscle important to have a sound understanding of • myofascial pain syndromes may have on the right side. Weakness of all muscles the anatomy of the sensory system.[6] Organic patchy areas of sensory changes; however,

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these are associated with well-defined trigger points in associated muscles Table 2. Red flags in back pain • peripheral injuries have specific History patterns with autonomic changes, such History of cancer Saddle anaesthesia as anhydrosis of the same area and Unexplained weight loss Loss of anal sphincter tone weakness of denervated muscles Steroid use over long periods Motor fall-out in lower limbs • neurological sensory loss remains Cannot lift left leg consistent − the sensory system does Recurrent UTIs A Fever not ‘forget’ which area it innervates, but Fever Tenderness over spinous processes patients forget. Pain – not relieved by rest Increased reflexes Bladder and bowel incontinence Limited spinal range of motion Keep the motor examination findings in Child less <10 years; adults >50 years mind when deciding on organic versus non- Urinary retention organic features.

The technique used to test sensation tale feature is that they want to show you Back pain may also elucidate inconsistencies in the how much stimulation they can take. Back and neck pain are among the most patient’s fall-out. It is good practice to test Beware of the person who asks you to common problems that confront the family sensation in such a way that the patient push the pin in. Testing of pinprick (pain physician. About 1 in every 4 patients in a cannot watch what you are doing (instruct – lateral spinothalamic tract),B light touch developed country reports low back pain. the patient to keep their eyes closed (antero-lateral spinothalamic tract) as Neck pain gets reported in 13% of people. and ask for a response when they feel well as proprioception (dorsal columns) is [8] Costs associated with management and anything, instead of asking ‘do you feel usually deemed sufficient for the general investigation adds up to $50 billion every this?’ every time). Malingering patients sensory examination. year in the USA.[9] It is therefore important are easily confused by position change, that every medical practitioner knows so it is a good idea to examine sensation Seizures when to investigate further these common with the patient on their back and repeat Epilepsy is one of the neurological complaints. ‘Red flags’ in back pain are listed Downward pressure on right leg testing after asking them to turn over. emergencies. It is important to differentiate in Table 2.[10] If the side of sensory loss changes from the ‘mimics’ of epilepsy and treat other causes one side to the other this is clearly not of seizures accurately from the beginning.[7] Waddell’s signs[10] are useful in deciding who organic. Some of the most convincing These can include migraine, parasomnia, needs further investigation (Table 3). The heel patients are those who say they can’t feel delirium tremens and psychosis. Apparent tap test[11] is a rapid alternative to Waddell’s pain when in fact they can and the tell- seizures are also one of the more common test. The patient sits on a bench with hips and non-organic hysterical attacks. The typical knees flexed at 90 degrees. The examiner then features of an epileptic attack are therefore suggests to the patient that the test may cause noteworthy: lower back pain and then lightly taps the • epilepsy can occur in any position or patient’s heel (Fig. 2). A complaint of sudden- posture – rule out postural causes such as syncope • personal injury such as tongue biting or bruising • unawareness of surroundings or events during a generalised • loss of autonomic control such as bladder incontinence • no clear trigger identifiable, such as stressful home events • temporal lobe epilepsy (complex partial seizures) may present with features of psychotic episodes or abnormal behaviour • unprovoked and surprising nature.

Epilepsy is, however, a broad topic and for the purpose of this article it is important to convey the following message – adult- onset seizures must be investigated to rule Heel tap out organic pathological conditions such as brain tumours. Fig. 2. Heel tap test.

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abnormalities and other neurological signs Table 3. Waddell’s signs indicate the need for further investigation Tenderness such as CT scanning of the brain and even Superficial Skin tender over large area of lumbar skin visual evoked potentials. Non-anatomical Not in a dermatome or myotome In young patients and those without Stimulation tests associated psychiatric diagnosis, complete Axial loading Pain on vertical pressure on patient’s skull – discount recovery of vision can be expected in neck pain up to 78% of cases. This good prognosis Rotation Back pain on passive rotation of shoulders and pelvis and reassurance should form the basis of in same plane management in patients with non-organic Regional signs Involves a widespread area – non-anatomically visual problems.[13] related Weakness ‘Giving away’ of many muscle groups – not explained anatomically About 1 in every 4 Sensory changes Non-dermatomal pattern patients in a developed Distraction: straight leg raising ‘Distract’ patient by comparing and country reports low back sitting on couch and extending the knee and ankle Overreaction Out of what might be expected – ‘over- dramatised’ pain. onset back pain is considered a positive common in general practice. Establishing Conclusion heel tap test. This test correlates well with that the objective visual acuity is better than Non-organic pathology is commonly Waddell’s test and can easily be incorporated the subjective visual loss is the mainstay of encountered in general practice. Neurological into any bench-side examination to identify evaluation. symptoms and signs are some of the most potential non-organic back pain. common areas of concern. An important Several tests are available to determine true start is a detailed history and a thorough Nausea and vomiting visual acuity as well as visual field deficits examination. The abovementioned lists are Nausea and vomiting are common. There and the reader is encouraged to read the not exhaustive. An opinion from another are, however, associated features that may article on non-organic visual loss for detailed doctor is always just a phone call away and indicate a neurological cause. Cerebellar description on these tests. In general there is a valuable way of ensuring that something lesions are probably the most commonly are four crude tests which can be done to is not missed. Most important in managing missed neurological cause of persistent evaluate non-organic visual loss:[12] patients with non-organic disorders is nausea and vomiting, especially in children. • an intact ‘menacing’ reflex (rapid The following are red flags: movement towards the eye – leading to • early-morning daily vomiting (in the reflex blinking or turning of the face) absence of pregnancy) – may indicate shows at least some crude vision present raised • moving a mirror in front of the blind eye • associated severe headaches and observing for pursuit movements • visual changes • checking for optokinetic nystagmus – • torticollis or opistotonus in children one needs at least 6/60 visual acuity if • any neurological signs such as motor deficit, this is present anisocoria, meningism and respiratory • testing of proprioception is independent pattern changes of vision – a person feigning blindness • recent head trauma might not know this and will therefore • previous neurosurgery, including endo- not be ‘able’ to tell position of joints in scopic third ventriculostomy or ventriculo- space. peritoneal shunt for hydrocephalus. Binocular visual acuity and visual field In the presence of any of the abovementioned defects are present in up to 80% of non- features a detailed neurological examination organic causes. This is rare in organic is required and a CT scan of the brain is pathology. The visual field abnormalities indicated. tend to be ‘too clear cut’ in non-organic defects. Signs that are too perfect are Vision problems suspicious. The pupillary light reflex and It is estimated that about 1% of visual accommodation reflex are non-voluntary problems seen by an ophthalmologist are and therefore important identifiers of non- non-organic in nature.[12] This is even more organic pathology. Associated cranial nerve

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reassurance that there is no life-threatening 5. Stone J. Functional neurological symptoms. J R 12. Blom AT, Whitehouse S, Orr B, Smith E. A new illness, and to give support. Always Coll Physicians Edinb 2011;41(1):38-41. [http:// sign of inappropriate lower back pain. Ann R emphasise the good prognosis, as their dx.doi.org/10.4997/JRCPE.2011.110] Coll Surg Engl 2002;84:342-343. [http://dx.doi. presentation is not always about personal 6. Voiss DV. Occupational injury. Fact, fantasy, or org/10.1308/003588402760452682] gain. Sometimes patients are just worried fraud? Neurol Clin 1995;13(2):431-446. 13. Beatty S. Non-organic visual loss. Postgrad Med about their health. 7. Smith PEM. Epilepsy: Mimics, borderland and J 1999;75(882):201-207. chameleons. Practical 2012;12(5):299- References 307. 1. Voon V, Lang AE, Hallett M. Diagnosing 8. Deyo RA, Mirza SK, Martin BI. Back pain psychogenic movement disorders - which criteria prevalence and visit rates: Estimates from US IN A NUTSHELL should be used in clinical practice? Nat Clin national surveys, 2002. Spine 2006;31(23):2724- • Hard neurological signs should always Pract Neuro 2007;3(3):134-135. [http://dx.doi. 2727. warrant further investigation. org/10.1038/ncpneuro0408] 9. Frymoyer JW, Cats-Baril WL. An overview of the • Make use of ‘trick’ tests, such as the 2. Mace CJ. ‘Hysteria’, ‘functional’ or ‘psychogenic’? incidences and costs of low back pain. Orthop heel-tap test, to catch out malingering patients. A survey of British neurologists’ preferences. J R Clin North Am 1991;22(2):263-271. • Children under 10 years should not have Soc Med 1991;84:471-475. 10. Bratton RL. Assessment and management chronic headaches – always investigate 3. World Health Organization. Headache disorders of acute low back pain. Am Fam Physician further. - fact sheet. Geneva: World Health Organization, 1999;60(8):2299-2308. • Persistent nausea and vomiting needs neurological workup, especially in children. 2011. http://www.who.int/mediacentre/factsheets/ 11. Waddell G, McCulloch JA, Kummel E, Venner • Acknowledgement and reassurance fs277/en/ (accessed 16 January 2013). RM. Nonorganic physical signs in low-back forms the mainstay of treatment in non- 4. Van Der Meyden C. Neurology Handbook. 1st pain. Spine 1980;5(2):117-125. [http://dx.doi. organic pathology. ed. Pretoria: University of Pretoria, 1999. org/10.1097/00007632-198003000-00005]

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