Tactile localization training for pain, sensory disturbance, and distorted body image: a case study of complex regional pain syndrome

Assessment of body perception disturbances in complex regional pain syndrome: A systematic review using the COSMIN guideline

OBJECTIVE

To conduct a systematic review to identify which tools are being used to assess body perception disturbances in Complex Regional Pain Syndrome (CRPS) and to provide an evidence-based recommendation in the selection of an assessment tool, based on measurement properties.

DATABASES AND DATA TREATMENT

Five electronic databases (EMBASE, Pubmed, PsycInfo, Science Direct and Web of Science) were searched for English or French written articles, with no time restrictions. All original articles using a body perception assessment tool with adult patients with CRPS were selected, regardless of their design (controlled trials, single case, qualitative study). Two investigators screened abstracts, selected full articles and extracted data independently.

RESULTS

Thirty-eight full-text papers were obtained and three main methods to evaluate body perception disturbances were identified: The Bath Body Perception Disturbance Scale, the Neglect-like Symptoms questionnaire adapted from Galer and the patient's body perception description. No full psychometric assessments were found. The Limb Laterality Recognition Task was also used in conjunction with another method.

CONCLUSIONS

Three main assessment methods for CRPS body perception disturbances are currently used. Full psychometric evaluation has not been completed for any of the assessment methods. As a consequence, we could not fully apply the COSMIN guideline. To date, there is no agreement concerning the use of a specific questionnaire or scale. The results indicate a need for further research such as psychometric properties of these questionnaires.

SIGNIFICANCE

This systematic review identified body perception disturbances assessment methods and their the psychometric properties in order to provide help and guidance to researchers and clinicians to investigate those clinical features.

Bodily Illusions and Motor Imagery in Fibromyalgia

Fibromyalgia (FM) is characterised by chronic, continuous, widespread pain, often associated with a sense of fatigue, non-restorative sleep and physical exhaustion. Due to the nature of this condition and the absence of other neurological issues potentially able to induce disorders in body representations per se, it represents a perfect model since it provides an opportunity to study the relationship between pain and the bodily self. Corporeal illusions were investigated in 60 participants with or without a diagnosis of FM by means of an ad hoc devised interview. In addition, motor imagery was investigated and illusions relating to body part movements and changes in body size, feelings of alienness, and sensations of body parts not belonging to one’s own body (disownership and somatoparaphrenic-like sensations) were found. Crucially, these symptoms do not correlate with any of the clinical measures of pain or functional deficits. The results showed that motor imagery was also impaired, and the severity of the deficits found correlated with the functional impairment of the participant. This indicates that disorders in body representations and motor imagery are part of the clinical expression of FM. However, while motor imagery seems to be linked to reduced autonomy and functional deficits, bodily illusions are independent and potentially represent a concurrent symptom.

Intervention Using Body Shadow to Evoke Loading Imagery in a Patient with Complex Regional Pain Syndrome in the Foot: A Case Report

We present the case of a female patient who developed complex regional pain syndrome (CRPS) after a right-foot injury. The patient had pain from the right knee to the toes and showed severe disgust at the appearance of the affected limb. Consequently, the affected limb was not fully loaded, and the patient had difficulty walking. General interventions, such as mirror therapy, were attempted, but the effect was limited. We hypothesized that this was due to the disgust toward the affected limb, and we implemented a body-shadow intervention that we developed. This reduced the disgust for the affected limb and improved pain, but neither changed the anticipated pain of loading the affected limb nor improved the patient’s walking ability. The reason for this was considered to be that the previous interventions using the body shadow utilized the third-person perspective, denoting that the image of the load sensation on the sole of the foot during walking was insufficient; therefore, we attempted a first-person body-shadow intervention. The results showed improvement in the patient’s walking ability. In CRPS of the foot, it is important to use interventions that evoke images of loading without causing anticipatory pain, pointing to the effectiveness of body-shadow interventions.

Preliminary Validation of a Two-Point Estimation Task for the Measurement of Sensory Dissociation in Patients with Chronic Low Back Pain

Objectives

Sensory dissociation (SEDI), the discrepancy between perception and actual size or shape of a painful body part, is a frequently observed finding in patients with chronic low back pain. However, the current methods of evaluating SEDI have several limitations, such as a qualitative nature and weak evidence supporting their reliability. In the current study, the reliability of two versions (manual and verbal) of a novel test, a two-point estimation task (TPE), was investigated.

Methods

To perform the manual version of the task, patients estimated the distance between two tactile stimuli delivered to their back using callipers, whereas in the verbal version they verbally reported the estimated distance.

Results

The manual version of TPE showed greater interexaminer reliability than the verbal version, and the mean of the two repeated measurements was sufficient for reaching excellent reliability for the pain-free (intraclass correlation coefficient [ICC] = 0.91, 95% confidence interval [CI] = 0.77–0.97) and painful (ICC = 0.86, 95% CI = 0.65–0.94) sides. Intra-examiner reliability was moderate to excellent (ICC = 0.66–0.96) for the manual version performed at the pain-free and painful sides. Distribution, duration, and intensity of pain significantly predicted SEDI and accounted for 42% of the total variance (corrected R2 = 0.42, P < 0.01).

Conclusions

TPE showed higher reliability coefficients compared with tools previously suggested in the literature and can therefore be used clinically and experimentally by one or more examiners. Further research is required to investigate the validity of this new test.

Embodied pain in fibromyalgia: Disturbed somatorepresentations and increased plasticity of the body schema

Fibromyalgia syndrome (FMS) is a highly prevalent, chronic musculoskeletal condition characterized by widespread pain and evoked pain at tender points. This study evaluated various aspects of body awareness in a sample of 14 women with FMS and 13 healthy controls, such as plasticity of the body schema, body esteem, and interoceptive awareness. To this end, the Rubber Hand Illusion (RHI), the Body Esteem Scale (BES), and the Body Perception Questionnaire (BPQ) were used, respectively. Consistent with increased plasticity of the body schema, FMS patients scored higher, with large or very large effect sizes, across all three domains evaluated in the RHI paradigm, namely proprioceptive drift and perceived ownership and motor control over the rubber hand. Scores on all items addressed by the BES were consistently lower among FMS subjects (2.52, SEM .19 vs 3.89, SEM .16, respectively, p < .01, Cohen’s d = .38-.66). In the FMS sample, BES scores assigned to most painful regions also were lower than those assigned to the remaining body sites (1.58, SEM .19 vs 2.87, SEM .18, respectively, p < .01). Significantly higher scores (p < .01, Cohen’s d = .51-.87) were found in the FMS sample across awareness (3.57 SEM .15 vs 1.87 SEM .11), stress response (3.76 SEM .11 vs 1.78 SEM .11), autonomic nervous system reactivity (2.59 SEM .17 vs 1.35 SEM .07), and stress style 2 (2.73 SEM .27 vs 1.13 SEM .04) subscales of the BPQ. Intensity of ongoing clinical pain was found to be strongly correlated with interoceptive awareness (r = .75, p = .002). The results suggest a disturbed embodiment in FMS, characterized by instability of the body schema, negatively biased cognitions regarding one’s own body, and increased vigilance to internal bodily cues. These manifestations may be interpreted as related with the inability of incoming sensory inputs to adequately update negatively biased off-line somatorepresentations stored as long-term memory.

Associations between tactile localization and motor function in children with motor deficits

Children with developmental disorders often have poor motor performance. This study aimed to address the association between tactile localization ability, an indicator of body image, and motor function in children with motor deficits. Eighteen children with motor deficits participated, and their upper and lower limbs were assessed. To assess the level to which the patient's body image was developed, a tactile localization task (TLT) was used. In the TLT, experimenters touched a child's fingers, toes, or lower extremities (L/E), and the participants were asked to identify the location of the touch on a body part illustration. We compared TLT ability between high and low motor function groups, and investigated the correlation between TLT and the measures of motor function, age, and non-verbal intelligence. The high motor function group had significantly higher L/E TLT scores than the low motor function group, except in the tests involving the fingers and toes. Furthermore, the L/E TLT correlated only with motor function measures (Gross Motor Function Measure score, measured using one-leg standing time and one-leg hopping ability). The results suggest that children with motor deficits experience developmental delay in terms of their body image.