Essay written for module on numbness and tingling in the feet

Portfolio task Module 5: A patient presents to clinic complaining of numbness and tingling in their toes on their right foot. What neurological assessments would you carry out and why?

Parasthesia (tingling) can be of a short or long duration and can be symptomatic of an underlying disease or nerve disorder (NIH 2023). Loss of sensation (numbness) can also have a similar aetiology within the sensory, motor or autonomic nervous systems (Burrow et al. 2020). To investigate the cause of these several different tests can be performed on the patient’s feet and legs to gain a holistic overview of capability and dysfunction.

Before any physical tests are performed the patient’s higher functions must be considered along with their current and past medical history (Burrow et al. 2020). An inspection should be made as they come into the clinic on their movement and gait, plus the attitude of their feet and any visible muscle wasting. Any involuntary movements should also be noted for further consideration as they may be indicative of lesions (Burrow et al. 2020).  

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From the spinal cord, 31 pairs of spinal nerves emerge from between the vertebrae into the peripheral nervous system, branch (rami) and then form plexuses which support different bodily areas – the lumbar, sacral and coccygeal support the lower limbs (O’Toole 2017).  One of the tests which may therefore be performed is dermatome testing as different nerves pathways can be mapped to different areas (Tortora and Derrickson 2017).  At these areas different sensations will be tested which link to different tracts in the spinal columns.

Tortora and Derrickson (2017) suggest five different types of tests: touch (tactile sensations and mechanoreceptors), pain (for the withdrawal reflex), temperature (for thermoreceptors), vibration and proprioception. 

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The femoral and sciatic nerves are the two major nerves that innervate the lower limbs. To check both afferent and efferent signals through the peripheral and central nervous system it is prudent to check the power of the muscles in the lower legs and feet (Tortora and Derrickson 2017).  This includes knee extension and flexion, ankle dorsiflexion and plantarflexion, foot inversion and eversion, plus toe function.  In addition to power, the tone of the muscles should also be checked and noted, along with any hypertonia or hypotonia.

The spinal cord also acts as an integration centre for some spinal reflexes such as the knee jerk (Tortora and Derrickson 2017). This, along with ankle jerk and plantar reflex, will check that the sensory receptors and neurons are functioning along that pathway, along with integration of information in the spinal cord and then motor neurons and effectors are optimally functioning and performing the reflex adequately. 

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The last set of tests to perform are based on co-ordination and position sense. These include the finger-nose test, heel-shin test, Rhomberg’s test and heel-toe walking.  These are important as the control of body movement and self-awareness is through the spinocerebellar tracts – any problems with the tests may therefore indicate issues in the cerebellum (Burrow et al 2020).

There are therefore several different tests which can be performed to check functioning of the central and peripheral nervous systems.  All this information can then be collated as necessary. 

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References

BURROW, G., ROME, K., AND PADHIAR, N., 2020. Neale’s Disorders of the Foot and Ankle, ninth edition, London, Elsevier.

NIH., 2023. Parasthesia [online] [viewed 12/2/23] Available from:  https://www.ninds.nih.gov/health-information/disorders/paresthesia

O’TOOLE, M., 2017. Mosby’s Pocket Dictionary of medicine, nursing and health professions 8th Edition, London, Elsevier.

SHIER, D., BUTLER, J., AND LEWIS, R., 2015. Hole’s Essentials of Human Anatomy and Physiology, New York, Mc-Graw-Hill Education.

TORTORA, G., AND DERRICKSON, B., 2017. Tortora’s Principles of Anatomy and Physiology, Glasgow, Wiley.