A REVIEW OF FOOT PAIN - A STEP FORWARD FOR THE PEDORTHIST ( PART 1 )
the pain perception is proportionate to the magnitude of noxious stimulation . The last criterion is described as the pain diminishes when the stimuli are removed . The activity within the nervous system producing the experience pain is termed nociception . 2
Within the feet these nociceptors are capable of both efferent and afferent transmission . 12 The transmission process occurs in three stages . The pain impulse is transmitted : from the site of transduction along the nociceptor fibres to the dorsal horn in the spinal cord ; from the spinal cord to the brain stem ; through connections between the thalamus , cortex and higher levels of the brain . The pain impulse is then transmitted from the spinal cord to the brain stem and thalamus via two main nociceptive ascending pathways . These are the spinothalamic pathway and the spinoparabrachial pathway .
While these pathways are complex , it is important for the pedorthist to maintain a clinical appreciation of the various levels at which dysfunction can occur and which therapy based on their mechanism of action assist in relieving foot pain .
Etiology of Foot Pain
Foot pain may be caused by many different conditions or injuries . Acute or repeated trauma , disease , or a combination of trauma or disease is the most common causes of foot pain . Trauma is a result of forces outside of the body either directly impacting the body or forcing the body into a position where a single or combination of forces result in damage to the structures of the body . Poor biomechanical alignment may lead to foot pain . Wearing shoes that are too tight or high heels can cause pain around the balls of the feet and the bones in that area . Shoes that are tied too tightly may cause pain and bruising on the top of the foot .
Vanderah recounts that tissue damage in the foot may occur by chemical , mechanical or thermal stimulation associated with direct trauma , musculoskeletal overload , infection or systemic or proximal pathology . 13 Mechanical stress either in part or fully has been the identified by Maganaris et al as the reason for many common types of foot pain such as tendonitis , stress fractures , calluses and corns . 15 Mechanical stress is a normal component of foot function ; however , tissue damage occurs when the maximum stress threshold is exceeded . 16 , 17 Three descriptors of mechanical stress have been identified : short duration along with high magnitude stress ; long duration with low magnitude stress ; or repetitive moderatemagnitude stress . 17
Footwear can be a contributor to foot pain . Poor fitting shoes in the short term can cause blisters , calluses , bruising and be a source of
athlete ’ s foot . The long-term effects may be
bunions ,
corns , irritation of nerves and joints , misalignment of the toes , and the source of microtrauma injuries to the foot .
Common Foot Pain Syndromes
Calluses and Corns The etiology of calluses is not clear . These foot lesions are hyperkerotic in nature : thick and hard superficial epidermis form from the body ’ s reaction to increase pressure . Calluses present in areas of localized high pressure , and the callus itself generates elevated plantar pressures . There is a high risk of foot ulceration with the presence of calluses in a diabetes patient who has a loss of protective sensation . Removal of the callus is essential in at-risk diabetes ; that is , those who have sensory deficit foot deformity , or who have had a previous foot ulcer . 18
Pedorthists can have a great impact on patient care by providing education to patients with these lesions . Some patients enjoy the autonomy of paring , trimming , or applying corn “ acid ” to their corns and calluses . Because of peripheral neuropathy , lack of muscular control , and poor eyesight common in diabetes patients , self-care could be disastrous and may result in loss of a limb . 18 Pedorthists can counsel diabetes patients on the dangers of the use of over-the counter salicyclic acid products and can emphasize this proper foot care through education to accentuate highlights previously made by the patient ’ s primary care provider and podiatrist on points of foot hygiene and foot protection . 18
Ingrown Toenail
An ingrown toenail , also known as a onychocryptosis occurs when the periungual skin is punctured by its corresponding nail plate , resulting in a cascade of foreign body , inflammatory , infectious and reparative process . 19 Anyone can get an ingrown toe nail , teenagers and older people get them more often because teenagers feet sweat more and older individuals have trouble caring for their feet . 20 In adolescence , feet perspire more often , causing the skin and nails to become soft , resulting in easy splitting . 21
An ingrown toe nail may be caused by ill-fitting shoes or incorrect clipping of the nails . Factors like poor peripheral circulation , increase age , and can contribute to the nail plate to curve inward and hence increase the likelihood of ingrown nails . Signs and symptoms for ingrown toe nails include : swollen toenail area or toe inflammation , toe inflammation with redden toenail area , toe pain , and pus under or besides the toe nail . Most mild to moderate ingrown toenails can be treated conservatively by soaking the foot in warm , soapy water and applying a topical antibiotic ointment . 20
Pedorthists should advise patients to always seek professional medical advice from a physician about any treatment or change in treatment plans if the ingrown toenail does not resolve in a timely fashion . The treatments for severe
ingrown toe nails include surgical intervention ( removal of the offending nail plate ),
antibiotics and antibiotic powders may be prescribed
16 Pedorthic Footcare Association www . pedorthics . org