Clinical, Psychological, and Neurophysiological Outcomes Associated with Pain and Function in Individuals with Unilateral Plantar Heel Pain

Abstract

Objective To assess the potential relationship between demographic (age, gender, body mass index, height, weight), clinical (affected side, duration of symptoms, health-related quality of life), psychological (depressive levels) or neuro-physiological (pressure pain sensitivity and number of trigger points -TrP-) outcomes with foot function and pain intensity in patients with unilateral plantar heel pain (PHP). Methods Fifty-four patients with PHP (48% females) were recruited. Demographic data, months with pain, time in standing position, depression, pressure pain thresholds (PPTs), number of TrPs, health-related quality of life, function and pain intensity were collected. A multivariable correlation analysis was performed to determine the association between the variables and a regression analysis was conducted to explain the variance in function and pain intensity. Results Pain intensity was negatively correlated with symptoms duration and calcaneus bone PPT and positively associated with gender, time in standing position and number of TrPs. Function was negatively correlated with PPTs on calcaneus bone, flexor digitorum brevis and abductor hallucis muscle and quality of life, and positively correlated with age, gender and depressive levels. Stepwise regression analyses revealed that 60.8% of pain intensity was explained by female gender, calcaneus PPTs, time in standing position, and function. Further, gender, quality of life, age, depressive levels and calcaneus bone PPTs explained 52.4% of function variance. Conclusions This study found that demographic, clinical, psychological and neuro-physiological variables can play a mutual interaction in function and pain intensity in patients with unilateral PHP. These findings could guide clinicians into the identification, prevention and treatment of PHP risk factors.

Analyzing the Interaction between Clinical, Neurophysiological and Psychological Outcomes Underlying Chronic Plantar Heel Pain: A Network Analysis Study

“…In addition, mechanosensitivity (PPTs) was also associated with foot function. The presence of pressure pain hypersensitivity and its association with higher pain intensity and limited foot function in individuals with chronic PHP has been reported in previous studies [ 13 , 18 ]. In fact, previous studies reported that 20.8% of pain intensity could be explained by foot function (contribution 2.8%) and calcaneus bone PPTs (contribution 18%) in PHP [ 18 ].…”

“…The presence of pressure pain hypersensitivity and its association with higher pain intensity and limited foot function in individuals with chronic PHP has been reported in previous studies [ 13 , 18 ]. In fact, previous studies reported that 20.8% of pain intensity could be explained by foot function (contribution 2.8%) and calcaneus bone PPTs (contribution 18%) in PHP [ 18 ]. According to those results, the current study has shown that the edges with the strongest weight were PPTs (i.e., calcaneus bone with plantar fascia, and sural nerve with tibialis anterior muscle), revealing the importance of pressure pain hyperalgesia in segmental-related areas and symptomatic areas for understanding and management of PHP.…”

“…In addition, emerging evidence also supports the presence of altered central nociceptive pain processing in people with PHP [ 13 , 14 ] related to pressure pain hyperalgesia [ 13 , 15 ]. Supporting these associations, some previous studies have reported different interactions between clinical, psychological, and neurophysiological variables in people with PHP [ 12 , 13 , 15 , 18 ]. However, these studies used Spearman’s rank-order correlation, Pearson’s Product-Moment Correlations, or linear regressions to determine the associations between the outcomes [ 12 , 13 , 15 , 18 ].…”

“…Supporting these associations, some previous studies have reported different interactions between clinical, psychological, and neurophysiological variables in people with PHP [ 12 , 13 , 15 , 18 ]. However, these studies used Spearman’s rank-order correlation, Pearson’s Product-Moment Correlations, or linear regressions to determine the associations between the outcomes [ 12 , 13 , 15 , 18 ]. It should be noted that Spearman’s rank-order correlation or Pearson’s Product-Moment Correlation ignore the potential for pairwise associations to arise from third-variable effects, whereas linear regressions ignore the possibility of bidirectional relationships between the variables [ 19 ].…”

“…Therefore, the aims of this study were: (1) to apply a network connectivity analysis including pain-related, function, clinical, mechanosensitivity, psychological, and health-related variables in individuals with PHP; and (2) to illustrate the potential of a network analysis for understanding underlying features of PHP and improving options for developing more targeted and effective treatment strategies. Based on the available literature [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 22 , 23 , 24 , 25 ], we hypothesized that pain intensity, foot function, number of trigger points, mechanosensitivity, depression, and quality of life will show multiple associations in individuals with PHP.…”