Having different feelings toward the affected area is not uncommon. In stroke, neglect is a well known feature and it is seen in CRPS. Kolb et al. (2012) looked at this phenomena and concluded that there could be a ‘neglect-like syndrome’ that differs from typical neglect.
Cognitive correlates of “neglect-like syndrome” in patients with complex regional pain syndrome.
Kolb L, Lang C, Seifert F, Maihöfner C.
Patients with complex regional pain syndrome (CRPS) often show distinct neurocognitive dysfunctions, which were initially termed “neglect-like symptoms.” So far, particularly the patients’ feelings about the affected extremity, motor, and sensory aspects of the “neglect-like symptoms” have been investigated, possibly pointing to a disturbed body schema. Because patients with classical neurological neglect show diminished awareness regarding the perception of their body, as well as of the space around them, our hypothesis was that CRPS patients exhibit some signs of personal neglect and extrapersonal visuospatial problems over and beyond those seen in patients simply suffering from limb pain. We used quantitative sensory testing and motor assessment aimed at detecting motor and sensory loss, a standardized questionnaire calculating a neglect score, and applied a detailed neuropsychological test battery assessing different parietal lobe functions, including visual neglect. We examined 20 CRPS patients and 2 matched control groups, one consisting of healthy subjects and the other one of patients with limb pain other than CRPS. Results show significant higher neglect scores for CRPS patients and the pain control group, but interestingly, CRPS patients and pain patients were indistinguishable. The results of the neuropsychological test battery did not demonstrate systematic variances, which would be indicative of a classical neurological neglect in CRPS patients, even though there were 3 CRPS patients who differed ≥ 2 SD from the mean of our healthy control group, with poorer results in ≥ 3 different tests. We assume that the “neglect-like syndrome” in most CRPS patients is different from typical neglect.
This paper a few years ago, highlighted the change in body schema in CRPS. This adaptation is a large focus for treatment certainly at our clinic with sensorimotor training forming part of the programme.
Left is where the L is right. Significantly delayed reaction time in limb laterality recognition in both CRPS and phantom limb pain patients.
Reinersmann A, Haarmeyer GS, Blankenburg M, Frettlöh J, Krumova EK, Ocklenburg S, Maier C.
The body schema is based on an intact cortical body representation. Its disruption is indicated by delayed reaction times (RT) and high error rates when deciding on the laterality of a pictured hand in a limb laterality recognition task. Similarities in both cortical reorganisation and disrupted body schema have been found in two different unilateral pain syndromes, one with deafferentation (phantom limb pain, PLP) and one with pain-induced dysfunction (complex regional pain syndrome, CRPS). This study aims to compare the extent of impaired laterality recognition in these two groups. Performance on a test battery for attentional performance (TAP 2.0) and on a limb laterality recognition task was evaluated in CRPS (n=12), PLP (n=12) and healthy subjects (n=38). Differences between recognising affected and unaffected hands were analysed. CRPS patients and healthy subjects additionally completed a four-day training of limb laterality recognition. Reaction time was significantly delayed in both CRPS (2278±735.7ms) and PLP (2301.3±809.3ms) compared to healthy subjects (1826.5±517.0ms), despite normal TAP values in all groups. There were no differences between recognition of affected and unaffected hands in both patient groups. Both healthy subjects and CRPS patients improved during training, but RTs of CRPS patients (1874.5±613.3ms) remain slower (p<0.01) than those of healthy subjects (1280.6±343.2ms) after four-day training. Despite different pathomechanisms, the body schema is equally disrupted in PLP and CRPS patients, uninfluenced by attention and pain and cannot be fully reversed by training alone. This suggests the involvement of complex central nervous system mechanisms in the disruption of the body schema.