How to use these guides
The articles in this series, which can be torn out for use in practice, are intended to support clinician development and to assist in the overall assessment of patient presentations. The information should be used to aid consideration of differential diagnoses in situations where life-threatening conditions have been ruled out.
The extent and explanation of each examination will not be to the depth of those provided in core literature texts, so further reading and consolidation are advised to support understanding supplemental to these articles. Key questions are included for reader consideration and to direct further study.
Most examinations are taught in a rigid format. However, in clinical practice, practitioners need to be flexible and adapt their approach depending on the presenting condition and circumstances. While there is no single set way to carry out each of these examinations, a good structure will reduce omissions and errors, and support the gathering of information to inform patient care.
Contemporary texts provide the underpinning reference sources throughout this series, as many of the examination processes and techniques are universally applied; however, differences will be highlighted. Readers will be signposted to these key texts for each clinical examination.
The series will cover the following systems:
- Cardiovascular system
- Peripheral vascular system
- Neurological system (upper and lower limbs)
- Cranial nerves
- Gastrointestinal system
- Respiratory system
- Musculoskeletal system
This month's article will follow on from the neurological examination discussed in last month's issue, and explain the assessment of the lower limbs. The structure of this assessment is similar and the same format will therefore be followed for the purpose of this clinical article. The general principles and purpose of this examination also remain the same, with the main difference being that the lower limbs, rather than the upper limbs, are being assessed. With all clinical examinations, it is important to introduce yourself. Consent must also be gained at the beginning of the examination, as well as before each specific part of the assessment. Ensure that you adhere to infection control measures throughout your assessment, washing hands and wearing appropriate personal protective equipment where required. For examination of the lower limbs, the limb should preferably be exposed. Ensure continued patient dignity and respect the patient's wishes throughout this examination.
The equipment required are the same as for the upper limb examination (Kirk, 2020). This includes:
- Cotton wool
- Tendon hammer
- Tuning fork 128 Hz (if available)
Unlike the upper limb examination, the ideal position for the lower limb assessment is for the patient to lay flat on their back (Japp and Robertson, 2018). For some parts of the assessment, there are differing positions that can be used, and these will be described within those respective sections of this article. Always compare and contrast your findings with each limb, assessing the non-impaired limb first. If an abnormality is detected, consider a more detailed assessment (Swartz, 2014; Japp and Robertson, 2018).
The structure of the lower limb examination is similar to that of the upper limbs (Japp and Robertson, 2018), and consists of the following:
The initial aspect of all assessments includes a general inspection of the patient and their surroundings. Look for any signs that may indicate neurological impairment; for example, walking aids, limb deformity, pain/discomfort, paralysis, muscle twitching or impaired gait.
Undertake a more detailed observation/inspection for muscle wasting, especially around the upper and lower leg muscles. Inspect for fasciculations, asymmetry, fine motor movements and deformity (Swartz, 2014; Talley and O'Connor, 2018).
For assessment of tone, ask the patient to relax their limb, engaging in light conversation to distract the patient from focusing on their leg movements. Roll the leg from side to side, assessing for signs of rigidity or flaccidity (Douglas et al, 2013). Then, flex and extend the knee at different speeds, feeling for increased tone (Talley and O'Connor, 2018), followed by the ankle (Bickley, 2017).
What is clonus and how is it elicited?
Assess the power of each limb and joint in turn.
Ask the patient to raise their straightened leg, and then repeat against resistance, pushing your hand down on their leg as they try to raise it from the bed. Then ask the patient to try and stop you from lifting their leg off the bed (Swartz, 2014). This assesses flexion and extension. Abduction and adduction can be tested by asking the patient to move their leg laterally as you resist, then asking them to bring their leg back in again, against resistance (Bickley, 2017).
With the patient's knee flexed at 90° and heel on the bed, ask the patient to extend their lower leg, first on their own, and then against resistance trying to push you away. Then ask them to flex their knee, trying to pull you towards them (Lindridge, 2016). An alternate method is to ask them to try and stop you lifting their heel off the bed (Swartz, 2014; Bickley, 2017).
Assess plantar flexion and dorsiflexion of the ankle joint, asking the patient to do so against resistance for each movement (Lindridge, 2016; Bickley, 2017). Then assess inversion and eversion of the ankle against resistance (Talley and O'Connor, 2018).
Similar to the ankle, the movement of the toes include plantarflexion and dorsiflexion, and tests power against resistance. This assessment primarily assesses the big toe only (Swartz, 2014).
How is power recorded/graded?
The assessment of coordination includes two separate tests: the heel-to-shin test and the foot-tapping test.
Ask the patient to run the heel of one of their feet down the shin of the opposite leg from the top of the tibia down to the foot in a straight line repeatedly. Then swap over and assess the alternate side (Lindridge, 2016; Walker, 2018).
With the patient sat up on the edge of the bed, feet dangling just above the floor, ask the patient to repeatedly tap their foot on the floor as quickly as possible (Bickley, 2017; Talley and O'Connor, 2018). If the patient is lying on the bed, ask them to tap your hand with their foot as quickly as they can (Thomas and Monaghan, 2014). Next, alternate and test the other foot.
What would you expect to find with impaired coordination? What could cause impaired coordination of the lower limbs?
Unlike two of the upper limb reflexes (biceps and supinator), reflexes of the lower limb are tested by directly striking the tendon. When assessing lower limb reflexes, ask the patient to interlock their fingers and pull apart as a method of reinforcement if needed (Tally and O'Connor, 2018).
Patella tendon reflex
This can be assessed with the patient lying flat, or sitting up. Palpate the inferior pole of the patella, then move your fingers distally down until you feel the bony prominence approximately 1–2 cm distal to the patella. This is the tibial tuberosity. The patella tendon lies between the inferior pole of the patella and the tibial tuberosity. With the patient lying down, support the lower leg and strike the tendon, looking for contraction of the quadriceps (Swartz, 2014). If the patient is sitting up, support the leg so the foot is not resting on the floor. With one hand on the quadriceps, strike the tendon with the tendon hammer in the other hand, feeling for contraction of the quadriceps and movement of the lower leg (Swartz, 2014; Bickley, 2017).
Achilles tendon reflex
The Achilles tendon lies superior to the heel of the foot. If the patient is lying flat, turn the foot/leg inwards (externally rotating the hip) so the tendon is turned medially, then strike the tendon directly (Walker, 2018).
An alternate position is if the patient is sitting up with legs dangling off the floor. Hold the foot with one hand; then strike the tendon hammer over the Achilles with the other (Swartz, 2014).
The plantar reflex can be assessed using a blunt object (for example, the opposite end of the tendon hammer). Then starting on the lateral side of the foot by the heel, stroke the upturned tendon hammer up the lateral aspect of the foot. Once at the ball of the foot, move medially (Bickley, 2017). For a normal reflex, the toes should curl inwards. This can be an uncomfortable feeling so the patient should be informed of this beforehand (Walker, 2018).
What is Babinski's sign?
Examination of sensation is undertaken assessing both light touch and pain. For light touch, using cotton wool or gauze, initially touch the patient's sternum as a control test. Then with the patient's eyes closed, touch each of the areas/dermatomes below for each limb, then compare with the opposite side.
For the assessment of pain, use a Neurotip following the same process as for light touch.
Bickley (2017) advises to vary the pace of touching with the dermatome so the patient does not predict the timing of repetition. Locations are as follows (Thomas and Monaghan, 2014; Tortora and Derrrickson, 2017):
- Medial aspect of the upper leg (L2)
- Medial aspect of the knee (L3)–(L3 rhymes with knee)
- Medial aspect of the lower leg (L4)
- Lateral aspect of lower leg (L5)
- Posterior aspect of the heel (S1)
- Posterior aspect of the lower leg (S2).
Using a 128 Hz tuning fork, strike and then place on the patient's sternum so they can feel the sensation through the non-vibrating end (Douglas et al, 2013). This is the control test. Then ask the patient to close their eyes, strike the tuning fork and place on the distal phalanx of their big toe (Walker, 2018). Ask the patient to inform you when you stop the vibration. If the patient is able to tell you correctly, the test will stop at this point. If they are unable to tell you, then move to the next bony prominence. Repeat this process gradually working up the limb until the patient is able to tell you when they feel the difference in vibration sensation. Bony prominences include:
- Metatarsal phalangeal joint
- Medial malleolus
- Greater trochanter of hip.
Walker (2018) highlights that if you suspect false positives, repeat the test but instead alternate with a vibrating or non-vibrating tuning fork, asking the patient to inform you if they feel the vibrations
Hold the big toe on either side with two fingers to stabilise the toe. Then with the patient's eyes closed, with your opposite hand, move the toe up and down, informing the patient which position the toe is in. Then move the toe randomly up and down, asking the patient to tell you the final position (Thomas and Monaghan, 2014). Repeat this three times. If the patient is able to correctly tell you, this will be the end of the test. If they cannot correctly tell you, repeat this test at the next proximal joint (ankle, knee, hip).
If the patient is already mobile on your arrival, you may wish to consider assessing their gait first. Talley and O'Connor (2018) advise to assess gait first if possible. Is their gait normal (Advanced Medical Life Support, 2017)? For an informal assessment, ask the patient to walk in one direction, turn and then walk back (Douglas et al, 2013). Look at their general movement, posture, stability and gait overall (Lindridge, 2016). A more detailed test can include walking heel to toe, on tiptoes and on their heels (Bickley, 2017).
What is ataxia and what can cause this to occur?
If you have just assessed their gait, while still standing ask them to stand with their feet together (Douglas et al, 2013). Then ask them to close their eyes for 20–30 seconds, according to Lindridge (2016) or 30–60 seconds according to Bickley (2017). Ensure you are close at hand to prevent them falling if they lose their balance (Thomas and Monaghan, 2014).
If a patient loses balance on closing their eyes, what can this indicate?
Similar to the assessments for the upper limb, consider the causes and clinical significance of any abnormality or impairment gleaned from your assessment, documenting your findings appropriately. If an abnormality is detected, consider further detailed assessment. This article highlights the main elements of assessment; however, there are further examination skills/tests that can be applied. On completion of your examination, ensure to thank the patient and cover them up again.