Introduce yourself, confirm the patient's name and date of birth, obtain consent and proceed to wash hands.
Begin the examination by asking the patient to lie comfortably on the bed. The bed should be no more than 30o. It is important to briefly assess the general appearance of the whole body, and that includes the upper limbs and face. Ensure that the patient is exposed from the waist downwards such that the entire lower limb can be seen.
Ask the patient about pain and comfort. Pain can indicate acute injury or be secondary to pathology. However, we primarily ask about pain to avoid hurting the patient and maximise their comfort. Next, look for paraphernalia around the bed. It is important to look out for walking aids, blood glucose monitors and medication.
Look for any scarring, rashes, muscle wasting, fasciculation or dyskinesia. Wasting and fasciculation can be due to a lower motor neurone (LMN) lesion, and it is most notable usually at the quadriceps femoris and anterior tibialis. Dyskinesia (involuntary movements) can be caused by a variety of pathologies including Huntington's disease.
Look at the shape, size, and general condition of the foot. Look for deformities such as hammer toe (a permanently bent toe at the proximal interphalangeal joint), flat foot or pes cavus (high arched foot). Charcot-Marie-Tooth disease can result in Charcot foot, in which there will be several mechanical and vascular features resulting in foot deformity.
Also keep an eye out for neuropathic, arterial or venous ulcers. The presentation of these is usually as follows:
Neuropathic: Painless, thick and keratinised ulcers. Usually found on the sole of the foot.
Arterial: Deep, punched out, painful and dry ulcers. Usually found between the toes, at the ball of the foot or the lateral malleolus.
Venous: Shallow and wet ulcers with an irregular border. Usually found in the medial gaiter region.
Some students use the mnemonic DWARFS to help remember what to look for in closer inspection. Dyskinesia, wasting, asymmetry, rashes, fasciculation, scars.
To assess tone, assess the muscle groups at the hip, knee and ankle joints, comparing each side like for like. Ensure the patient is relaxed, place your hands on their knee and roll the leg such that there is rotation at the hip. Repeat with the other leg. Lift each knee briskly at least 30cm off the bed and then release - the knee should drop and the leg straighten. If the foot also comes off the bed with the knee, then this indicates hypertonia.
Circumduce the ankle joints. Circumduction assess all of the possible movements at this joint: flexion, extension, abduction, adduction and rotation.
Finish by testing for clonus by holding the sole of the patient's foot, quickly dorsiflexing the ankle, and holding it firmly flexed in that position. If there are greater than 5 involuntary contractions (beats) of the gastrocnemius muscle, then that may be a sign of an upper motor neurone lesion.
Hypotonia: This is usually due to a LMN lesion. Decreased tone is difficult to detect, so caution on presenting. Hypertonia: Hypertonia, or spasticity, can be described in different ways:
Clasp-knife rigidity: This is due to an upper motor neurone lesion. On movement at the knee joint, initially there will be high resistance. This will be followed by a rapid decrease in resistance where there will be a sudden "give" of the muscle.
Lead-pipe rigidity: This is due to Parkinson's disease. There will be a sustained high resistance to passive flexion of the knee joint.
Cogwheeling: A jerky resistance to passive movement due to a combination of lead-pipe and tremor. This is also due to Parkinson's and may be detected when circumducing the ankle joint.
Hip: Ask the patient to raise one of their legs whilst keeping the knee extended. Test flexion (L2-3, femoral nerve) and extension (L4-5, inferior gluteal nerve and sciatic nerve) at the hip joint by applying a downwards and upwards force, while asking the patient to resist. Do the same with the other leg.
Knee: Flex the patient's knee to a 90o angle whilst keeping the foot flat on the bed. Test extension (L3-4, femoral nerve) and flexion (L5,S1, sciatic nerve) by asking the patient to kick out and pull their leg in, against resistance.
Ankle: Test ankle dorsiflexion (L4-5, deep peroneal nerve) and plantar flexion (S1,2, tibial nerve) by asking the patient to resist an upward and downward movement.
IMPORTANT: It is imperative that during assessment of power you isolate the joints. For example, when assessing extension at the knee, be sure to push on the patient's hamstrings to prevent any hip extension.
Additionally, you should be comparing power on each side, like for like.
There is no need to isolate the hip joint, as that is achieved through the positioning of the patient.
Power can be graded using the Medical Research Council (MRC) scale as follows:
0 - No contraction.
1 - Trace of contraction (fasciculation).
2 - Active movement with gravity eliminated.
3 - Active movement against gravity.
4 - Active movement against gravity and resistance.
5 - Normal power.
Decreased power indicates muscle weakness. It is important to identify the pattern of distribution. Weakness at one muscle group could indicate a mononeuropathy. Symmetrical and proximal weakness could be a result of myopathy. If the extensors are weaker than flexors, then there may be hemiparesis. In reporting, focus on the movement affected and the grade of power.
Show the patient the tendon hammer and orange stick, and proceed to test reflexes. There are three reflexes to elicit.
The patellar reflex (L3-4): Take the weight of the leg and ask the patient to relax. Tap the patellar tendon, which is superior to the tibial tuberosity and inferior to the patella.
The calcaneal reflex (S1-2): Bend the knee at 90o and with one hand, dorsiflex the ankle joint. Ask the patient to relax and tap the calcaneal tendon on the posterior aspect of the ankle.
The plantar reflex (L5, S1-2): Run an orange stick up the lateral sole of the foot in the direction of the big toe. As you approach the base of the toes run the stick medially. The toes should plantarflex in normal circumstances. If they dorsiflex, then the patient is Babinski sign positive.
Hyporeflexia: This is usually due to an LMN lesion. The reflex arc involves LMNs in both the afferent and efferent pathways. Hence, if there is a lesion to the LMNs involved in the reflex arc, there will be hyporeflexia.
Hyperreflexia: This is usually due to an upper motor neurone (UMN) lesion. Whilst UMNs are not directly involved in the reflex arc, they exert an inhibitory effect which dampens the reflex response. If there is any lesion to an UMN corresponding to a reflex arc, then this may lead to hyperreflexia.
This is a special term used for when the toes dorsiflex on eliciting the plantar reflex. It is a sign of an upper motor neurone lesion.
Sensation should be assessed in the distribution of the dermatomes. A dermatome is an area of skin which is supplied by a single spinal nerve root. Below are listed the areas of skin which are supplied by a single dermatome only.
L1 - On the anterior surface of the proximal thigh.
L2 - On the anterior surface of the middle of the thigh, 15-20cm above the knee.
L3 - On the anterior surface of the knee.
L4 - On the anteromedial surface of the middle of the leg, 15-20cm below the knee.
L5 - On the dorsum of the foot at the third metatarsophalangeal joint.
S1 - On the most lateral and distal aspect of the sole of the foot, at the base of the little toe.
There are five parts to sensation, and they include response to fine touch, pain, temperature change, vibration and joint position. Direct the patient extend their legs such that they are in the anatomical position, as this will make it easy to assess sensation at each dermatome. It is also important that you ask the patient to close their eyes before assessing any sensation modality.
Light touch is assessed using cotton wool. Lightly press the cotton to the patient's sternum to use as a reference ("calibration") and subsequently assess light touch at each dermatome. Be sure to compare sensation on each side, like for like.
Pain is assessed using a neurotip. A neurotip has a blunt and a sharp end. The patient should be able to distinguish between the two. Demonstrate the difference on the patient's sternum and proceed to assess pain sensation at each dermatome with an unpredictable pattern of sharp and blunt touches.
Temperature is assessed with the use of hot and cold test tubes. Again, demonstrate the difference on the sternum and proceed to assess each dermatome systematically in a similar, unpredictable way as before. It is unlikely that you will be required to do this in any OSCE scenario, however it is important to be aware of the proper procedure.
Vibration sense is assessed using a 128Hz tuning fork. Place the vibrating tuning fork on sternum and ask the patient when the vibration stops (manually stop the vibration yourself to save time). Proceed to do the same at the interphalangeal joint of the big toe. If the patient cannot accurately determine the presence or absence of vibration then continue to sequentially assess at the metatarsophalangeal joint of the big toe, the medial malleolus at the ankle joint and the lateral femoral condyle at the knee until you are confident that vibration sense is detected.
Joint position, or proprioception is also assessed at the interphalangeal joint of the big toe. Flex and extend the joint with the patient watching and indicate which way is "up" and "down". Manipulate the joint with the patient's eyes closed and eventually stop in the "up" or down" position. Ask the patient to say which position the big toe is in and repeat this thrice. If the patient is unable to accurately determine joint position at the interphalangeal joint of the big toe, then, just like with vibration sense, proceed to test proximally at the metatarsophalangeal joint of the big toe, the ankle joint and the knee joint.
Dorsal columns-medial lemniscus pathway: Light touch, vibration sense and proprioception in the lower limb are communicated to the midbrain via the gracile fasciculus of the dorsal columns in the spinal cord. Information then travels via the medial lemniscus to the contralateral thalamus before communicating with the primary somatosensory cortex.
Spinothalamic tract: Light touch, pain and temperature sensation are communicated directly to the thalamus via the contralateral spinothalamic tract of the spinal cord.
Light touch is in fact the least useful modality to assess sensation with because whilst it is mainly communicated to the brain by the dorsal columns-medial lemniscus pathway there is also communication in the spinothalamic tract.
If there is loss of sensation at a particular dermatome, this suggests injury to the spinal root, as a dermatome is a patch of skin supplied by a single spinal root.
If there is a loss of sensation in a non-dermatomal distribution, this indicates injury to the peripheral nerves, causing a peripheral neuropathy.
Mononeuropathy: This is where there is a lesion to a single peripheral nerve. For example, in carpal tunnel syndrome, the median nerve is compressed, and there is sensory loss to the lateral aspect of the palmar surface of the hand.
Polyneuropathy: This is where there are lesions to multiple peripheral nerves. Polyneuropathies are often symmetrical to the left and right sides and often start distally moving more proximally. In diabetes mellitus for example, there can be a loss of sensation in the hands and feet in a "glove and stocking" distribution. Other causes of polyneuropathy include alcohol abuse (due to a deficiency of vitamin B1 [thiamine]), or a deficiency of vitamin B12.
Place your palms just below the patient's feet and ask them to tap your palms with their left foot only, right foot only, both feet together and then both feet interchangeably. Inability to do this with ease suggests dysdiadochokinesia, a phenomenon indicative of cerebellar pathology.
Ask the patient to place their right heel on their left knee whilst you place your hand half a metre above their left foot. Next, instruct them to move their right heel down to their left ankle, and then lift their foot in the air such that their toes touch your hand. Then ask the patient to repeat this motion. After about 5 seconds of continuous movement ask them to do the same using the left heel instead. This exercise tests for dysmetria, a phenomenon also indicative of cerebellar pathology.
Dysdiadochokinesia is a term for the inability to perform rapid alternating movements. It is a feature of cerebellar ataxia. Dysmetria is a term for a lack of coordination movement when there is purposeful movement, that is to say, when there is undershoot or overshoot when trying to reach a certain position. Dysmetria is also a feature of cerebellar ataxia
Ask the patient to stand upright with their feet together and arms by their side. Ask them to maintain this position while they close their eyes. If there is a loss of balance at this point then the patient tests "positive" for Romberg's sign, and they have a loss of vestibular function or proprioception.
It is important that at all times you are standing by the patient ready to catch them if they begin to fall. If the patient has a cortical or cerebellar lesion, then they may fall even when just getting off the bed.
Romberg's test is performed on the premise that the body requires at least two out of the following three senses to be functioning adequately to maintain balance while standing: vision, vestibular function and proprioception. If the patient can stand with their eyes open, then it can be said that vision and either one of vestibular function or proprioception are intact. Once the eyes are closed, then the patient is purely reliant on the latter two senses to maintain balance, and so if they fall, then this indicates that there is a problem with vestibular function, proprioception or otherwise the dorsal columns which communicate proprioception.
Romberg's test cannot be performed if the patient has a cerebellar lesion, as in that case, they will be unable to stand upright in the Romberg position with their eyes open. It is important to not confuse cerebellar ataxia with a positive Romberg's test, as the latter cannot even be performed in the presence of the former.
Following a negative Romberg's test, ask the patient to walk for 5m and check for any abnormalities in gait. These are described in the Complex Box below.
If the patient appears to have a normal gait, ask them to walk back to you heel-to-toe. This is more sensitive in picking up cerebellar ataxia.
Upper motor neurone associated gaits:
If there's a unilateral lesion, there will be circumduction of the leg on the affected side, with the leg dragging behind the patient in a semi-circular fashion. This is known as a circumduction or hemiplegic gait. It occurs because hypertonia in an UMN legion causes flexion of the pelvis, hip and legs, which produces a crouching-like posture. The adductors are tight, pushing the knees together. If both legs are affected (bilateral lesion), the knees approach each other evern closer and can often cross with each step, producing a "scissoring gait".
Lower motor neurone associated gaits:
In a peripheral motor neuropathy, there will be muscle wasting and loss of function in the affected leg(s), and this may have an impact on gait. For example, injuries to the L5 nerve root or the common peroneal nerve will result in a relative inability to dorsiflex at the ankle joint (foot drop). Whilst walking, the patient will naturally attempt to compensate for this by raising their leg higher, resulting in a high stepping gait.
Peripheral sensory neuropathy associated gaits:
Sensory neuropathies may affect all modalities, including light touch, pain, temperature, vibration sense and proprioception. As a result, patients often lose their balance easily. To steady themselves, they spread their legs apart, resulting in a broad-based gait. Additionally, patients will not know what force to use when in contact with the ground, and will often exaggerate their step, resulting in a stamping gait. They rely on their sight to aid with walking, and therefore Romberg's test will be positive.
Myopathy and myasthenia gravis associated gaits:
Myopathies affect muscles more proximally (closer to the spine), particularly the hip abductors. If this occurs bilaterally, then there will be then there will be a "hip drop" on both sides leading to a waddling gait.
If however only one set of hip abductors is affected, for example due to trauma to the muscles or the corresponding superior gluteal nerve, then, when the patient raises their contralateral leg (the side without the lesion), their hip will unilaterally drop on the uninjured side (sound side sags). This phenomenon, known as Trendelenberg's sign, will produce a special gait known as Trendelenburg's gait.
Patients with cerebellar lesion have a lack of coordination, resulting in a characteristic cerebellar or ataxic gait. Features of such a gait include a broad-base, irregular steps and swaying. See the cerebellar examination page for more details.
Patients will have a stooped posture with a reduced arm swing and a narrow-based, shuffling gait. They will take short, accelerating steps, which is referred to as a festinating gait.
Early on, patients may present with just the reduced arm swing on one side. This may be elicited this by lightly rocking the patient's shoulder side to side to see if both arms swing equally.
Antalgic gait: The patient walks in a manner to avoid pain. They will have a lengthened "swing phase" and will attempt to reduce weight bearing on the affected leg.
Complete the examination by offering to obtain a full history, perform an upper limb and cranial nerve examination and then, if appropriate, suggest further tests such as nerve conduction studies (if nerve damage is suspected), a CT scan (if a recent stroke is suspected) or an MRI scan (if a demyelinating disorder or spinal lesion is suspected).
When assessing each other, please click on each list item as you go along. Doing so will turn the list item green. Make careful note of any steps missed at the end.
We recommend completing any examination or procedure in under 10 minutes, but you can adjust the timer to suit your needs.
Introduction: “Hello, I’m SimpleOSCE and I am a medical student. I need to examine and test the nerves in your legs today, would that be okay? Can I confirm your name and DOB? Thank you.”
Position the bed flat and ensure adequate exposure.
Ask about pain or discomfort.
General inspection of the face, upper limbs and around the bed (walking aids, medication).
Closer inspection of the lower limbs for scarring, rashes, wasting, fasciculation, dyskinesia or tremor.
Check tone at the hip, knee and ankle joints.
Ensure patient is relaxed and then test for clonus.
Check power at the hip, knee and ankle joints.
Ask the patient to relax and elicit the patellar and calcaneal reflexes. Attempt to do this twice per muscle only.
Test for the plantar reflex using an orange stick.
Check light touch sensation at all dermatomes with cotton wool (dorsal columns/spinothalamic).
Demonstrate sensation first on sternum and ensure patient's eyes are closed throughout.
Offer to check pain with neurotip (spinothalamic).
Offer to check temperature with hot and cold test tubes (spinothalamic).
Test proprioception by moving the big toe at the interphalangeal (IP) joint (dorsal column).
Test vibration sense using the 128Hz tuning fork at the IP joint of the big toe (dorsal column).
Test for dysmetria through "heel sliding" exercise.
Test for dysdiadochokinesia through "foot tapping" exercise.
Ask patient to stand with feet together to test for ataxia. Be ready to support patient if they fall.
Perform Romberg's test ("close your eyes").
Assess the patient's gait by walking and heel-to-toe.
Thank and cover up the patient.
"To complete my exam, I would like to take a full history and perform an upper limb neurological examination as well as a cranial nerve examination."