Examination: introduction

Introduction

In training medical students and doctors how to examine the nervous system there is an entirely appropriate emphasis on technique. It is important to learn how to elicit physical signs correctly. However, this can lead to the students tending to think more about technique and less about what information they are meant to be getting from the examination. Students often dive into the active part of the neurological examination and miss important physical signs that can be seen if looked for, for example the relative facial immobility in Parkinson’s disease.

The examination is used, like the history, as a screening test and as an investigative tool (Fig. 1). In patients in whom you anticipate a normal examination (e.g. migraine or epilepsy), a simple screening examination is appropriate (Box 1). The examination is used to investigate the hypotheses generated by the history and to clarify and understand any abnormalities found on the screening examination. For example, sensory examination of the hand will need to be done carefully in a patient with sensory symptoms affecting the hand; this would not be done in the same detail in a patient who presented with blackouts.

Fig. 1 Approach to neurological examination.

Box 1 Screening neurological examination

Gait

Pupils – direct and consensual reactions

Test fields to hand movements

Fundoscopy

Eye movements to pursuit on upgaze and lateral gaze

Facial sensation to light touch with finger tip in all three divisions of the trigeminal nerve

Facial movement – ‘screw up your eyes, show me your teeth’

Mouth – ‘open your mouth (look at tongue) and say ‘arrh’ (observe palate). Please put out your tongue’

Test neck flexion

Arms

– look for wasting

– test tone at wrist and elbow

– observe outstretched arms with eyes closed

– test power (shoulder abduction, elbow flexion and extension, finger extension and abduction and abductor pollicis brevis)

– reflexes (biceps, triceps arid supinator)

Legs

– look for wasting

– test tone at hip

– test power (hip flexion and extension, knee flexion and extension, foot dorsiflexion and plantarflexion)

– reflexes (knee and ankle and plantar response)

Sensation

– test joint position sense in toes and fingers

– test vibration sense on toes and fingers

– test light touch and pinprick distally in hands and feet

Coordination

– test finger–nose and heel–shin

When considering the examination as a whole you should try to answer the following questions:

Are there any abnormalities?

Can the abnormalities be explained by a single lesion?

Can the abnormalities be explained by several discrete lesions?