Clinical Research on Foot & Ankle
Open Access

Foot pain; Therapeutic; Clinical practice; Diagnosis

Introduction

Between 17% and 42% of the adult population experience foot pain. Disability occurs in nearly half of these cases and can affect mood, behavior, risk of falling, ability to care for oneself, and quality of life. Foot pain is complex, and the difficulty in accurately diagnosing the source of pain and tissue damage can hinder clinical pain management. However, most people with foot pain do not seek professional care, even if the pain bothers them. It is clear that there is a need [1]. At present, the pathogenic mechanisms underlying several types of tissue injury within the foot are not clearly understood. As a result, interventions targeting foot pain in clinical trials often lack specific targets (e.g. plantar heel pain). Perhaps as a result of this limitation, evidence from randomized controlled trials of some common interventions (such as custom foot orthoses) highly valued in clinical practice has found little, if any, beneficial effect.

A deeper understanding of pain is needed to identify the nature and mechanisms of foot pain, its diagnosis, and the best clinical interventions. It's been 20 years since a review on foot pain was published. Given that almost every foot pain prevalence study has been conducted since then, this type of review is warranted in addition to recent advances in understanding the nature and mechanisms of pain in general [2]. The purpose of this paper was to comprehensively review the literature on foot pain, with particular reference to its definition, prevalence, etiology and predictors, classification, measurement, and impact. Finally, we discuss the complexity of foot pain as a sensory, emotional, and psychosocial experience in the context of clinical practice, therapeutic studies, and placebo effects.

Defining Foot Pain

Foot pain is an unpleasant sensory and emotional experience following the perception of damage to tissues distal to the tibia or fibula. Includes bones, joints, ligaments, muscles, tendons, epiphyses, retinaculum, fascia, bursae, nerves, skin, nails, and vascular structures [3]. Foot pain is a general term that does not indicate pain class, injury mechanism, or histologic pathology. As discussed further in a later section, paw pain is not the activity of nociceptive pathways induced by nociceptive stimuli, but rather the perception of these processes and their consequent effects on distress and pain-related behaviors.

Prevalence of Foot Pain

Few studies have examined the prevalence of foot pain in large, randomly selected samples. Instead, attention is usually focused on specific medical conditions (such as heel pain) or population groups (such as those over 65). Overall, foot pain is estimated to affect 14% to 42% of people at any given time, depending on pain definition and measurement, sample characteristics (age, gender), and study location. Garo et al. Among those reporting disabling foot pain, the most commonly reported sites of foot pain were the metatarsal/arch area (25.6%), the first metatarsal head (20.2%), %), big toe (15.9%) [4], and heel plantar surface (15.5%). Further research is needed to characterize the exact types of foot pain in the general population.

Aetiology of Foot Pain

Foot tissue injury may be chemical, mechanical, or thermal associated with direct trauma, musculoskeletal overload, infection, or systemic or proximal pathology (e.g., nerve entrapment, diabetic neuropathy). It can be caused by irritation. Many common types of foot pain, such as tendonitis, stress fractures, corns, and calluses, are routinely attributed in whole or in part to mechanical stress force) [5] is a normal part of foot function, but tissue damage occurs when the maximum tissue load threshold is exceeded. This can occur when: (1) high stress in a short time; (2) long term, low stress; or moderate intensity repetitive stress.

Associations and Predictors of Foot Pain

By identifying factors that predict foot pain, doctors can modify or prevent the factors and even target risk groups with preventative strategies and more appropriate treatments. An increasing number of females and females are associated with foot pain. However, the prevalence of disabling foot pain has been shown to increase with age in both men and women, peaking between the ages of 55 and 64 (15% in women and 12% in men). , reported to decrease with increasing age decreases steadily. In contrast, studies specifically focused on leg pain in older adults suggest another, with a prevalence of up to 42% [6].

Disabling foot pain usually appears to be associated with other areas of pain, such as hip/leg pain, axial skeletal pain, and/or shoulder pain. It is more likely to occur in patients previously diagnosed with arthritis, diabetes, and/or stroke. In the largest study to date, Garrow et al. [7] People who reported rheumatoid arthritis were three times more likely to report ineffective leg pain, although they did not reach statistical significance due to the very small number of people included in this part of the analysis.

Garo et al. Also, in the north west of England, people between the ages of 18 and her 80 were more likely to have nail problems (42% vs 22%), corns, than those with no leg pain but disabled leg pain. Yatako (41% vs. 30%), hallux valgus (19.5% vs 7%), swollen feet (34% vs 10%), flat/flat feet (9% vs 6%), high arches/concave feet (18% vs 13%) and toes Deformation (33% vs. 13%) (p<0.05). An association has also been reported between foot pain and flatfoot disabling and limited ankle range of motion in older Australians. In a study by Garrow et al. However, foot problems diagnosed by podiatrists using established criteria found only foot swelling to be correlated with ineffective foot pain (43.7% vs. 18.0%; OR: 3.8 95% CI: 1.7 to 8.2) [8]. This unexpected result has been reported by Badlissi et al. He who is 65 years and older with foot pain is more likely to have hallux valgus, flat feet, or little finger deformities (including mallets, mallets, nails, or overlapping toes and bunionets) than those without foot pain reported to be low. However, Badlissi found a relationship between foot pain and concave feet. Discrepancies between these studies may be due to differences in specimen characteristics and diagnostic/classification criteria.

Extrinsic factors commonly associated with foot pain include inappropriate footwear and occupational activities, although these areas have received little empirical research in the past [9]. For both, further research is needed to develop predictive models for the onset of leg pain in large prospective randomized samples of children, adolescents, and adults.

Pathology

Pathological foot pain occurs after nociceptive pathology. With dysfunction of the peripheral or central nervous system or both [10]. Although there is some debate as to which type of pain should be classified as pathological foot pain, neuropathic, inflammatory, and chronic pain are often suggested. It is classified as pathologic leg pain because at least one of the three criteria for leg pain is not met. So, in pathological foot pain: (1) the noxious stimulus is intrinsic to the nervous system; (2) the perception of paw pain is disproportionate to the level of nociceptive stimulus; and/or (3) removal of the stimulus does not relieve pain in the foot; Because of such dysfunction, pathological foot pain goes far beyond the role of mechanical defense responses resulting from physiological foot pain.

Quantifying Foot Pain

There are currently no generally accepted standards for measuring pain. As a result, a number of quantitative and qualitative pain measurement tools have been developed [11]. Because pain is a subjective sensory and emotional experience, participants' own pain statements are widely considered to be the most valid representations of their pain. Therefore, self-reported pain intensity is the most commonly used research tool to measure pain. Common tools include visual analog scales (VAS), numeric rating scales, and linguistic category/Likert scales. Tools used to measure foot pain include the: Foot Function Index; Foot Health Status Questionnaire, physical health domains of the Diabetes Foot Ulcer Scale; Manchester Foot Pain and Disability Index; Rowan Foot Pain Assessment Questionnaire; American Academy of Orthopaedic Surgeons Foot and Ankle Questionnaire. Across all these tools, the individual's subjective reporting of pain is regarded as a valid representation of their pain. However, criticism of pain intensity outcome measures have concluded that: people preferentially use the beginning, middle and end of continuous pain scales (e.g. VAS) [12]; there are specific clinical attributes of pain class not always captured in generic tools (e.g. chronic/inflammatory/neuropathic); the fluctuating nature of many pain conditions are often inappropriately disregarded; the results of intervention trials are often difficult to interpret due to unknown or unspecified clinically important differences detected by the pain measurement tool used.

Despite these limitations, foot pain as an outcome measure has much to offer clinical practice and research. It is important, however, to ensure that pain reduction does not dominate health outcome assessment in clinical practice. Jensen et al. Pain relief is dangerously equated with treatment success, suggesting that many other clinically relevant health outcomes are consequently overlooked [13].

The placebo effect

It has been suggested that the psychosocial context surrounding the intervention (such as attitudes and expectations) contributes to positive treatment outcomes. This is called the placebo effect and can occur in both clinical trials and clinical practice. In clinical trials, researchers can attempt to separate the placebo effect from the direct physiological effects of the intervention. This is usually achieved by a sham intervention without intentional bioactivity (e.g. sugar pills or detuned ultrasound) and is colloquially referred to as a placebo [14]. A “placebo effect” is the change in outcome observed after administration of a placebo intervention. Due to the biologically inert nature of placebo interventions, observed changes are usually attributed to the psychosocial context surrounding the intervention. However, the term "placebo effect" is sometimes misused. Placebo effects include only changes that occur as a direct result of administration of the intervention. For example, placebo effects may include the Hawthorne effect where a person changes their behavior because they know they are being watched /monitored. Placebo effects do not include changes that would have occurred if the placebo intervention had not taken place, including spontaneous progression or spontaneous resolution of symptoms and/or signs [15]. Overall, it is difficult, and sometimes impossible, to distinguish between changes that occur as a result of placebo administration and changes that would otherwise occur. It is widely accepted historically to be more than a result or a reflection of normal disease progression. In fact, the placebo effect has been described as the most effective intervention known to science. It has undergone more clinical trials than any other intervention, usually exceeds expectations for efficacy, and is effective for a seemingly infinite range of conditions. A significant increase was reported in a double-blind, randomized controlled trial. You can now reduce symptoms by an average of 35%. Despite these claims, the results of meta-analyses assessing the presence of placebo effects are conflicting. Systematic reviews by the Cochrane Collaboration assessing the effects of placebo interventions in any clinical condition included binary endpoints (where response to treatment is measured as one of two possible endpoints) or objective studies. , no statistically significant placebo effect was found. Endpoints (when outcomes are measured by an observer, such as blood pressure) [16].

Placebo effects have been observed in clinical trials of custom foot orthoses. However, as with many physical, mechanical, and surgical procedures, developing a convincing placebo procedure for custom foot orthoses is extremely difficult and perhaps impossible. Often uses "fake" interventions. Sham interventions are designed to have minimal mechanical effects, yet look and feel like real interventions. As a result, these dummy devices often produce some kind of mechanical effect. Distinguishing between real placebo effects and potential mechanistic effects of sham braces and effects of changes that would have occurred without intervention (eg, natural history of disease) is complex. Despite these limitations, studies attempting to understand the mechanisms by which custom foot orthoses reduce foot cavity pain have found that the placebo effect associated with custom foot orthoses as an intervention is strong and clinically meaningful for symptoms. I knew it could bring about some change.

Many theories have been proposed to try to explain the basis for the placebo effect. (2) reduced anxiety (a key emotional component of pain); (3) the expectation of improvement from the intervention; at the psychophysiological level, functional brain imaging has identified neurochemical circuits that are activated when participants expect or believe they will receive pain-relieving interventions. In fact, changes in brain activity are similar to those that occur when real interventions are performed. As such, there is growing evidence that subjective components (such as expectations and values) have physiological underpinnings that yield powerful regulation of fundamental perceptual, motor, and internal homeostatic processes. However, it has been hypothesized that the contributions of various neurotransmitters and neuropeptides involved in this placebo-induced activity modulation may be disease-and symptom-specific. There is currently no brain imaging studies evaluating placebo effects on foot pain interventions.

Although it is desirable to minimize the magnitude of the placebo effect in clinical trials, it is possible to achieve clinically meaningful benefits by intentionally maximizing the placebo effect in the clinical setting. Further research is needed to determine if (and if so, how) this can be achieved. Until further clinically guiding evidence is presented, clinicians need to recognize that what patients think matters.

Conclusion

This leg pain overview has discussed its prevalence, etiology and predictors and impact. We also discussed the complexity of foot pain as a sensory and emotional experience, and how psychosocial conditions influence treatment response to create a 'placebo effect'. We hope to provide a platform to advance the diagnosis and treatment of foot pain in humans and its evaluation in clinical trials.

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