Foot For Thought: Plantar Cutaneous Sensation and Standing Balance Post-Stroke

Department of Physical Therapy professor Dr. Kara Patterson publishes The relationship of plantar cutaneous sensation and standing balance post-stroke in Topics in Stroke Rehabilitation journal.

Dr. Patterson’s recent study explores the effect of decreased ability to detect light touch at the sole of the foot (or plantar cutaneous sensation) on standing balance in stroke patients. In collaboration with Department of Physical Therapy Assistant Professor Dr. Avril Mansfield (status only) and lecturer Elizabeth Inness of Toronto Rehabilitation Institute, Dr. Patterson and former MSc student Stephen Parsons have conducted a secondary analysis to determine the exact level at which a person’s sensation impairment affects their balance.

Using monofilament tests to detect sensation at the sole of the foot, and comparing this data to the results of balance tests in people post-stroke, Dr. Patterson has been able to pinpoint the threshold where foot sensation is related to poor standing balance.

Monofilament testing: a flexible, thin wire gently touches the sole of a patient's foot

 

“While previous studies have explored the relation of motor control and cognitive function to balance, we have limited understanding of how impaired cutaneous sensation affects balance in these particular patients” says Dr. Patterson. “Our work has shown that foot sensation does play a role in standing balance, and that above an objective cut-point, which is 4.31 on the monofilament sensation measurement scale, patients are likely to experience difficulties with standing balance.”                                                        

 

Monofilament test

“Now, when a therapist performs sensory testing on a patient, and say the sensation at the bottom of the patient’s foot is 4.65, this clinician will be able to assume that their patient’s sensation is poor enough that it is contributing to their balance impairment. This marker did not exist before” explains Dr. Patterson. Her study will help clinicians determine whether sensation is a contributing factor to their patients’ poor standing balance, and may guide them to customize elements of their rehab program to address sensory impairments.

A patient stands on squares that measure balance.

“A lot of post-stroke rehab is focused on motor-recovery, and sensory-recovery receives less attention, because it is more difficult to measure and we have less evidence to guide us on how to treat it” asserts Dr. Patterson. “I view this study as a step towards increased awareness around the role of foot sensation in relation to standing balance, and our next steps should be finding more effective treatments for this type of sensory impairment in stroke.”

 

Balance testing