Laura Perucca

Rehabilitating patients with left spatial neglect by prism exposure during a visuomotor activity

OBJECTIVE Adaptation to prisms displacing the visual scene rightward is a therapeutic tool for left unilateral spatial neglect (USN). We aimed at comparing the effects of the classic adaptation procedure (repeated pointing toward visual targets, control treatment, C), with those of a novel adaptation method, involving ecological visuomotor activities (experimental treatment, E). METHOD In 10 right-brain-damaged USN patients, each treatment was given for 1 week, with a crossover design, for a total of 20 sessions, twice per day. USN was assessed by cancellation, reading, and drawing tasks, and by a standardized scale. Neurological severity was assessed by the National Institutes of Health (NIH) stroke scale (Brott et al., 1989), disability by the Functional Independence Measure (FIM) scale. RESULTS The 2-week treatments (EC, CE) were equally effective, improving both USN, confirming previous reports (Frassinetti, Angeli, Meneghello, Avanzi, & Làdavas, 2002) and, importantly, disability. The improvement was independent of baseline performance, duration of disease, and neurological severity. Recovery took place after the first week, continued in the second week, and was stable at the follow-up of 3 months. The improvement of USN, measured by cancellation performance, and, in part, that of disability, measured through the FIM scale, were mediated by the size of the leftward aftereffects, suggesting a causal relationship between prism exposure and recovery. The E protocol was better tolerated. CONCLUSIONS Daily life visuomotor activities, associated with prism exposure, are a useful tool for rehabilitating USN patients. This new treatment may widen the compliance with prism exposure treatments and their feasibility within home-based programs.

Short form of the Dizziness Handicap Inventory: construction and validation through Rasch analysis.

A new item response scale is presented, which measures the severity of self-reported balance deficits. The scale, DHIsf, is a short form of the Dizziness Handicap Inventory. The scale was constructed and validated by Rasch analysis. Rasch analysis was applied to rescore or remove any items misfitting, redundant, or off-target, until an optimal instrument was obtained. The 25-item, 3-level Dizziness Handicap Inventory was, thus, reduced to the 13-item, 2-level DHIsf. The retained items explore the domains of eye/head movements, full body activities, and mood alterations. Data were collected from 55 outpatients (63 +/- 13 yr; 43 females) attending otoneurological rehabilitation referral at a general hospital because of complaints of dizziness or imbalance. They were fully independent in ambulation and showed no evidence of major neurological or orthopedic diseases. Objective tests included brain computed tomography, sovraaorctic Doppler sonography, craniocorpography, static posturography, and nystagmography. The findings were categorized as pathologic, borderline, or normal. At least one examination was borderline or abnormal in 42 patients. The DHIsf was well targeted on this sample, with a mean score of 5.7/13 (standard deviation, 2.8; median, 5; range, 1-13). The Rasch statistics showed that the 13 items evenly fitted a hierarchy of difficulty within a homogeneous construct. A moderate but significant variance explanation of DHIsf measures was provided by a two-way analysis of variance model, with craniocorpography and nystagmography as independent categorical variables (r2 = 0.15; P = 0.018). When the clinical tests were individually taken into account, their outcome (dichotomized as abnormal v borderline or normal) could not be predicted by either of the DHIsf measures or raw scores (logistic regression). The DHIsf compares favorably with the original Dizziness Handicap Inventory, shows some consistency with the instrumental findings, and provides original information on the severity of imbalance syndromes, as it is seen from the patients perspective.

Measuring mobility in people with lower limb amputation: Rasch analysis of the mobility section of the prosthesis evaluation questionnaire.

OBJECTIVE To assess the psychometric properties of the Mobility Section of the Prosthesis Evaluation Questionnaire (PEQ-MS). DESIGN A postal survey, including self-report assessment of prosthetic capability and performance with the PEQ-MS and the Locomotor Capabilities Index, and of other variables associated with prosthetic wear and use. The PEQ-MS data underwent Rasch analysis for rating scale diagnostics and a reliability and validity study. PATIENTS A total of 123 subjects (mean age 54 years) who had undergone lower limb amputation in the previous 5 years and who had completed rehabilitation and a prosthetic training programme. RESULTS According to Rasch analysis and expert review, some response categories of the PEQ-MS (13 items, 11-level numeric rating scale) were collapsed and one item was deleted. The remaining 12 items fitted to the Rasch model and created a revised scale with a 5-level response format, the PEQ-MS12/5. The PEQ-MS12/5 demonstrated good reliability (person-separation reliability = 0.95, item-separation reliability = 0.98) and internal construct validity. Moreover, the correlation with the Locomotor Capabilities Index (rs = 0.78) and with prosthetic wear and use (rs range 0.41-0.59) supported the convergent validity of the PEQ-MS12/5. CONCLUSION The new PEQ-MS12/5 presents good psychometric characteristics for measuring mobility in people with lower limb amputations. These preliminary results provide an already applicable instrument and a solid basis for further validation studies.

The FIM instrument in the United States and Italy: a comparative study.

Tesio L, Granger CV, Perucca L, Franchignoni FP, Battaglia MA, Russell CF: The FIM™ instrument in the United States and Italy: A comparative study. Am J Phys Med Rehabil 2002;81:168–176. ObjectiveTo compare FIM™ instrument ratings between Italy and the United States. DesignThis study utilized 169,835 United States and 4,536 Italian FIM instrument records for stroke with the left side of the body affected, stroke with the right side of the body affected, and orthopedic conditions. ResultsCase-mix, patient age, and admission and discharge FIM instrument scores were similar. The delays between onset of disability and admission to rehabilitation and lengths of stay in rehabilitation were 2–4 times longer in Italy. In Italy, some 88–95% of the subjects were discharged to the community vs. 74–88% in the United States. Hierarchies of FIM instrument ratings across the motor and cognitive items were similar, but there were interesting differences. The hierarchical patterns showed that dressing, bathing, perineal hygiene, and tub or shower transfer were relatively more difficult in Italy compared with the Unites States, whereas walking was easier in Italy compared to the United States. ConclusionThe Italian health care payment system offers less incentive for early discharges from acute care and rehabilitation. In Italy, nursing homes are less accessible, whereas family support is more available. Apparently less intensive treatment is applied in Italy, where a minimum time per day for rehabilitation services is not mandatory for payment. Occupational therapy is not used in Italy and the focus is more on physical therapy.

The influence of age on length of stay, functional independence and discharge destination of rehabilitation inpatients in Italy

Advanced age in itself does not predict a poor functional outcome or a longer length of stay in rehabilitation units. Seven hundred and sixty-four adult cases were analysed, from 14 post-acute rehabilitation facilities throughout Italy. Data came from the national database run by the agency distributing the Italian version of an internationally validated scale of disability, the FIM [symbol: see text] sm (Functional Independence Measure). The FIM is an 18-item scale rating independence in the domains of selfcare, sphincter control, mobility, locomotion, communication and social cognition. The total FIM score may range from 18 to 126 (higher score = greater independence). Patients were classified with respect to the cut-off age of 75 years (76+ and 75-, mean age 82 and 57 years, n = 203 and 561, 27% and 73% of the cases, respectively). The median interval between onset of disability and admission to the facility (onset-to-admission delay, OAD) was 36 and 45 days in the 76+ and the 75- group, respectively (p < 0.001). Mean admission FIM score was 70 (+/- 28) in the 76+ and 71 (+/- 27) in the 75- group. Discharge FIM scores were 84 +/- 29 and 93 +/- 26, respectively (p < 0.001). Median length of stay (LOS) was 34 days in the 76+ and 41 days in the 75- group, respectively (p < 0.005). The 76+ and 75- groups were discharged home in 86% and 90% of the cases, respectively (p = 0.053). The results suggest that inpatient rehabilitation is substantially effective and efficient for older as well as for younger patients.

Walk Ratio (Step Length/Cadence) as a Summary Index of Neuromotor Control of Gait: Application to Multiple Sclerosis.

In healthy adults, the step length/cadence ratio [walk ratio (WR) in mm/(steps/min) and normalized for height] is known to be constant around 6.5 mm/(step/min). It is a speed-independent index of the overall neuromotor gait control, in as much as it reflects energy expenditure, balance, between-step variability, and attentional demand. The speed independence of the WR in patients with multiple sclerosis (MS), and its capacity to discriminate (a) across patients with MS and controls and (b) among disability levels in MS were tested. The WR was computed in 30 outpatients with MS [20 women, 10 men; Extended Disability Status Scale (potential range: 0–10, observed median 3.5, range 2.5–5.0)] walking at free speed (range: 0.43–1.67 ms−1), and in 30 healthy controls (20 women, 10 men) at free and slow speed (range: 0.55–1.67 ms−1). The WR was 6.38±0.66 in controls versus 5.36±0.86 in patients with MS (P<0.000), independent of age, sex, and walking speed. The WR was 5.95±0.69 and 4.90±0.70 in patients with an Extended Disability Status Scale score (P<0.001) below or above the median, respectively, independent of the disease duration (P<0.000). In patients with MS, the WR is a disability-sensitive index of neuromotor control of gait, and thus a promising outcome measure for treatments aimed at improving motor coordination.

Electromyographic latency of postural evoked responses from the leg muscles during EquiTest Computerised Dynamic Posturography: Reference data on healthy subjects

No normative data are available for the latencies of the EMG signals from the ankle muscles in response to sudden sagittal tilt (toes-UP or toes-DOWN) or shift (shift-FOR or shift-BACK) of the support surface during standing. In this study the postural evoked response (PER) paradigm on the EquiTest™ force platform was applied to 31 healthy adults (18 women and 13 men; mean age 29 years). The EMG latencies (PEREMG) were computed both through the standard manual procedure and through a specially designed automated algorithm. The manually computed PEREMG onset yielded a 95% tolerance interval between 82ms and 148ms after toes-UP perturbation, between 93ms and 182ms after toes-DOWN perturbation, between 67ms and 107ms after shift-BACK perturbation, and between 73ms and 113ms after shift-FOR perturbation. When comparing the two methods, paired t-tests showed no significant mean difference (Bonferroni-adjusted p-values ranged from 0.440 to 1.000) and all Bland-Altman plots included zero difference within the limits of agreement. Therefore, the manual and the automated methods appear to be sufficiently consistent. These results foster the clinical application of PEREMG testing on the EquiTest platform.

Bimanual dexterity assessment: Validation of a revised form of the turning subtest from the Minnesota dexterity test

Bimanual coordination underlies many daily activities. It is tested by various versions of the old Minnesota Dexterity Test (dating back to 1931, ‘turning’ subtest). This, however, is ill standardized, may be time-consuming, and has poor normative data. A timed-revised form of the turning subtest (MTTrf) is presented. Age-related norms and test–retest reliability were computed. Sixty-four healthy individuals, 24–79 years, comprising 34 women, were required to pick up 60 small plastic disks from wells, rotate each disk, and transfer it to the other hand, which must replace it, as quickly as possible. Two trials were requested for each hand (ABBA sequence). The average time (seconds) across the 4 trials gave the test score. Participants were grouped (CART algorithm) into 3 statistically distinct (P<0.05) age×score strata, with cutoff 53+ and 73+ years, and tested at baseline and after 1 week. Test–retest reliability was measured both as consistency [intraclass correlation coefficient (ICCs) model 2.1] and as agreement (Bland–Altman plot). From the ICCs, the individual test–retest minimal real difference (in seconds) was computed. The whole MTTrf took less than 4 min to administer. Baseline scores ranged from 40 to 78 s. The ICCs ranged from 0.45 to 0.81 and the minimal real difference ranged from 6.68 to 13.40 s across the age groups. Fifty-nine out of 64 observations (92%) fell within the confidence limits of the Bland–Altman plot. The MTTrf is a reliable and practical test of bimanual coordination. It may be a useful addition to protocols of manual testing in occupational therapy.

Surgical leg rotation: cortical neuroplasticity assessed through brain mapping using transcranial magnetic stimulation

Rotationplasty (Borggreve-Van Nes operation) is a rare limb salvage procedure, most often applied to children presenting with sarcoma of the distal femur. In type A1 operation, the distal thigh is removed and the proximal tibia is axially rotated by 180°, remodeled, grafted onto the femoral stump, and then prosthetized. The neurovascular bundle is spared. The rotated ankle then works as a knee. The foot plantar and dorsal flexors act as knee extensors and flexors, respectively. Functional results may be excellent. Cortical neuroplasticity was studied in three men (30–31 years) who were operated on the left lower limb at ages between 7 and 11 years and were fully autonomous with a custom-made prosthesis, as well as in three age–sex matched controls. The scalp stimulation coordinates, matching the patients’ brain MRI spots, were digitized through a ‘neuronavigation’ optoelectronic system, in order to guide the transcranial magnetic stimulation coil, thus ensuring spatial precision during the procedure. Through transcranial magnetic stimulation driven by neuronavigation, the cortical representations of the contralateral soleus and vastus medialis muscles were studied in terms of amplitude of motor evoked potentials (MEPs) and centering and width of the cortical areas from which the potentials could be evoked. Map centering on either hemisphere did not differ substantially across muscles and participants. In the operated patients, MEP amplitudes, the area from which MEPs could be evoked, and their product (volume) were larger for the muscles of the unaffected side compared with both the rotated soleus muscle (average effect size 0.75) and the muscles of healthy controls (average effect size 0.89). In controls, right–left differences showed an effect size of 0.38. In no case did the comparisons reach statistical significance (P>0.25). Nevertheless, the results seem consistent with cortical plasticity reflecting strengthening of the unaffected leg and a combination of cross-education and skill training of the rotated leg.

Short-Term Repeatability of Stabilometric Assessments

ABSTRACT The authors evaluated the short-term (within-day, between-days) repeatability of center of pressure (COP) displacements. COP sway area and speed were obtained in the morning and afternoon of two separate days, both with open (EO) and closed (EC) eyes, in 10 healthy adults. Agreement and variability among conditions were tested by ANOVA and Bland-Altman plots. Mode (EO/EC, area: p = .032; speed: p < .004), and day (day1/day2, area: p = .006; speed: p = .02) showed significant differences. The EC condition and the second test day showed the largest values, with medium-large effect sizes. Time-of-day did not influence COP displacements. Speed had better agreement than area (Bland-Altman plots). COP displacements were well reproducible within-day, but had significant between-days variations. COP assessments should be performed in the same session.