Body Representation Alterations in Patients with Unilateral Brain Damage.

OBJECTIVE: Systematic studies about the impact of unilateral brain damage on the different body representations (body schema, body structural representation, and body semantics) are still rare. Aim of this study was to evaluate body representation deficits in a relatively large sample of patients with unilateral brain damage and to investigate the impact of right or left brain damage on body representations (BRs), independently from deficits in other cognitive processes. METHOD: Sixty-four patients with unilateral stroke (22 with left brain damage, LBD; 31 with right brain damage without neglect, RBD-N; 11 with right brain damage with neglect, RBD+N) and 41 healthy individuals underwent a specific battery including BR as well as control tasks. RESULTS: In more than a third of the sample, selective (37.5%) and pure (31%) deficits of BR were presented and equally distributed among the different BRs (˜10% for each representation), with selective (27.2%) and pure (22.7%) body schema deficit mainly presented after left brain damage. As a group, patients with unilateral brain damage, independently of the side of lesion (LBD, RBD-N, RBD+N), had significantly worse performance on body structural representation with respect to healthy individuals, whereas LBD had numerically worse performance on body schema with respect to healthy individuals and RBD-N. No significant differences among groups were found on body semantics. CONCLUSION: BR deficits are not a rare consequence of unilateral brain damage and are independent of a more general cognitive dysfunction. Accordingly, the need for an accurate assessment and specific neuropsychological training in clinical settings is discussed.

Interoceptive awareness in focal brain-damaged patients.

BACKGROUND: Interoception is the basic process enabling evaluation of one's own internal state of body, but its alteration in brain-damaged patients has not been adequately investigated. Our study aimed to investigate awareness of visceral and somatosensorial sensations in brain-damaged patients with unilateral stroke. METHODS: Sixty patients (22 with left brain damage, LP; 25 with right brain damage without neglect, RPN-; and 13 with right brain-damage and extrapersonal and/or personal neglect, RPN+) and 45 healthy controls (HC) completed the Self-Awareness Questionnaire (SAQ), a self-report tool for assessing interoceptive awareness with two domains related to visceral (VD) and somatosensory feelings (SD), respectively. RESULTS: Comparing the SAQ subdomains scores between three groups of patients (LP, RPN-, and RPN+) and HC, we found that RPN+ had significantly lower scores on VD than HC and LP, whereas no significant difference was found on scores of SD between groups. CONCLUSION: Our results support the hypothesis of a right-hemispheric dominance for "interoceptive neural network" suggesting that processing of visceral sensations would be located mainly in the right hemisphere. Therefore, a careful assessment of interoceptive awareness in clinical practice would be useful to improve rehabilitation and to engage patients with deficit of interoceptive awareness in developing greater accuracy of body signals.

Evaluation of autologous platelet concentrate for intertransverse lumbar fusion.

INTRODUCTION: The aim of the study was to analyze if the adding of autologous platelet concentrate (APC) to a mixture of local autograft plus tricalcium phosphate and hidroxiapatite (TCP/HA) would improve the fusion rate in posterolateral lumbar fusion. MATERIALS AND METHODS: A prospective, controlled, blinded, non-randomized clinical trial was carried out in 107 patients affected by degenerative lumbar pathology. The study group consisted of 67 patients, in which autologous platelet concentration was added to a mixture of autologous local bone graft and TCP/HA. A control group of 40 patients with same pathology and surgical technique but without APC addition was used to compare the fusion mass obtained. By means of plain X-rays, a blinded evaluation of the intertransverse fusion mass quality at twelve and twenty-four months was made according to type A (bilateral uniform mass), type B (unilateral uniform mass) and type C (irregular or lack bilateral mass). Patients with type C were regarded as pseudoarthrosis. RESULTS: In the study group 17 patients had lack or irregular fusion mass (25.4%) versus three patients in the control group (7.5%), which was statistically significant. CONCLUSIONS: This study shows that the adding of autologous platelet concentration to a mixture of autologous bone graft plus TCP/HA has decreased our rates of posterolateral lumbar fusion.