Evaluation of 3 pushrim-activated power-assisted wheelchairs in patients with spinal cord injury.

OBJECTIVE: To assess differences between manual wheelchairs and 3 pushrim-activated power-assisted wheelchairs (PAPAWs): Servomatic A and B and E-motion. DESIGN: Repeated measures. SETTING: Rehabilitation hospital. PARTICIPANTS: Volunteers with spinal cord injuries (N=52). INTERVENTIONS: Ten subjects propelled the wheelchairs on a dynamometer, 46 evaluated each wheelchair on indoor and outdoor courses, and 10 evaluated their ability to transfer themselves and their wheelchairs into and out of their car. MAIN OUTCOME MEASURES: Oxygen consumption per unit time (V˙o2) and heart rate were measured during propulsion on the dynamometer. Wheelchair efficiency on the indoor and outdoor courses was evaluated on the basis of heart rate, completion time, handrim push frequency, and patient satisfaction. RESULTS: On the dynamometer, decreases in V˙o2 and heart rate were similar with the 3 PAPAWs compared with manual wheelchairs. On the outdoor course, heart rate was significantly decreased by PAPAWs compared with manual wheelchairs and patient satisfaction was better with Servomatic devices than with the E-motion device. Indoors, the course completion time was longer with the E-motion wheelchair than with other wheelchairs in the overall population, and handrim push frequency was higher with the E-motion wheelchair than with other wheelchairs in the subgroup with T12 to L1 injuries. Car transfer ability was lower with PAPAWs than with manual wheelchairs. CONCLUSIONS: Differences exist across PAPAWs. Compared with E-motion, the 2 Servomatic PAPAWs were easier to use outdoors, and difficulty transferring into/out of the car was similarly increased with all 3 PAPAWs.

Hand versus mouth for call-bell activation by DMD and Becker patients.

Severe hand dysfunction is common in patients with Duchenne muscular dystrophy (DMD) and may preclude the use of conventional call-bells. We prospectively evaluated a call-bell with two hand-controlled interfaces (push-button and key-pinch) and two mouth-controlled interfaces (sip-or-puff) in 32 consecutive DMD and Becker patients. Patients called intentionally 348 times, using the sip-or-puff device 237 times and the hand-controlled interfaces 147 times. Use of the hand-controlled interfaces correlated with key-pinch strength (R=0.366; P=0.04). Six patients reported being unable to call with the hand interfaces and five patients reported temporary call failure due to inaccessibility of the sip-or-puff interface. Ease-of-use scores on a visual analogue scale were best for puff, followed by sip then key-pinch interrupter and push-button (8.7+/-2.1, 7.5+/-2.7, 6.2+/-3.9, and 0.5+/-2.0 respectively; ANOVA: P<0.00001). In conclusion sip-or-puff devices should be considered more often to provide neuromuscular patients with greater independence.

Optimization of power wheelchair control for patients with severe Duchenne muscular dystrophy.

The extended survival of patients with Duchenne muscular dystrophy (DMD) achieved by the introduction of mechanical ventilation is raising new quality-of-life issues. We evaluated passive range of wrist extension, key pinch strength, and power wheelchair driving in 84 patients. The 47 drivers with restricted driving abilities were older than the 37 unrestricted drivers (27.2+/-5.0 y vs. 22.8+/-3.8 y) and had worse upper limb performance. By multiple logistic regression, only key pinch was significant ( R(2) = 0.224, P = 0.02. Eighteen restricted drivers were reassessed after having swapped a conventional joystick for another control system (mini-joystick, isometric mini-joystick, finger joystick, or pad) and having moved the position of the tested control system so that the patient could use it with different fingers, his chin or his mouth. All of them regained the ability to drive unrestricted. Adults with DMD gradually lose their ability to drive with a conventional joystick but can regain unrestricted driving with alternative control systems.

Recombinant human acid alpha-glucosidase (rhGAA) in adult patients with severe respiratory failure due to Pompe disease.

Pompe disease is a rare metabolic myopathy caused by lysosomal α-glucosidase deficiency. Pompe disease ranges from a rapidly progressive course when symptoms present in infancy to a more slowly progressive rate when symptoms present in childhood or adulthood. This open-label prospective exploratory study investigated the effect of 12 months of recombinant enzyme replacement therapy in 5 adult patients who had already advanced to a very severe stage of Pompe disease. Muscular and respiratory function, quantitative muscle testing and spirometry were assessed. Four patients were tracheostomized. Respiratory parameters did not deteriorate. A moderate improvement in sitting/supine slow vital capacity in 2 patients (from 7% to 11% and 28% to 32% of predicted) and reductions of ventilation support in 2 patients was observed. Three patients, wheelchair bound at baseline, improved sitting and proximal motor function; 2 patients improved in their ability to stand and transfer. The treatment was well tolerated. Alglucosidase alfa may stabilize or even slightly improve muscle strength and respiratory function among patients with severe Pompe disease.

Whole-body muscle MRI in 20 patients suffering from late onset Pompe disease: Involvement patterns.

To describe muscle involvement on whole-body MRI scans in adult patients at different stages of late-onset Pompe disease. Twenty patients aged 37 to 75 were examined. Five were bedridden and required ventilatory support. Axial and coronal T1 turbo-spin-echo sequences were performed on 1.5T or 3T systems. MRI was scored for 47 muscles using Mercuri's classification. Whole-body scans were obtained with a mean in-room time of 29 min. Muscle changes consisted of internal bright signals of fatty replacement without severe retraction of the muscles' corpus. Findings were consistent with previous descriptions of spine extensors and pelvic girdle, but also provided new information on recurrent muscle changes particularly in the tongue and subscapularis muscle. Moreover thigh involvement was more heterogeneous than previously described, in terms of distribution across muscles as well as with respect to the overall clinical presentation. Whole-body MRI provides a very evocative description of muscle involvement in Pompe disease in adults.

Comparative evaluation of electric wheelchair manoeuvrability.

OBJECTIVE: The aim of this study was to determine whether manoeuvrability varied between electric wheelchairs. DESIGN: Randomized, prospective, repeated measures design. SUBJECTS: Twelve wheelchair users. METHODS: Three different electric powered indoor/outdoor wheelchairs (Invacare Storm 3, Ottobock B500, and Meyra Champ) intended for use by patients with severe impairments were tested over an indoor and an outdoor circuit. Points were assigned when the users touched the circuit boundaries or failed to pass obstacles. The users completed the Quebec User Evaluation of Satisfaction with Assistive Technology questionnaire (QUEST). RESULTS: Performance was significantly worse with Ottobock B500 compared with the other 2 wheelchairs on the indoor test (Wilcoxon, p < 0.05 for both comparisons) and compared with Invacare Storm on the outdoor test (Wilcoxon, p < 0.05). The mean 6-item QUEST score, effectiveness, and simplicity of use were significantly worse for Ottobock B500 than for the other 2 wheelchairs (Wilcoxon, p < 0.05). CONCLUSION: Differences in manoeuvrability exist between commercially available electric wheelchairs belonging to the same category. Driving tests and QUEST provide complementary and concordant information.

A single homozygous point mutation in a 3'untranslated region motif of selenoprotein N mRNA causes SEPN1-related myopathy.

Mutations in the SEPN1 gene encoding the selenoprotein N (SelN) have been described in different congenital myopathies. Here, we report the first mutation in the selenocysteine insertion sequence (SECIS) of SelN messenger RNA, a hairpin structure located in the 3' untranslated region, in a patient presenting a classical although mild form of rigid spine muscular dystrophy. We detected a significant reduction in both mRNA and protein levels in the patient's skin fibroblasts. The SECIS element is crucial for the insertion of selenocysteine at the reprogrammed UGA codon by recruiting the SECIS-binding protein 2 (SBP2), and we demonstrated that this mutation abolishes SBP2 binding to SECIS in vitro, thereby preventing co-translational incorporation of selenocysteine and SelN synthesis. The identification of this mutation affecting a conserved base in the SECIS functional motif thereby reveals the structural basis for a novel pathological mechanism leading to SEPN1-related myopathy.