A prospective, longitudinal, descriptive study of the effect of a customized wheelchair cushion on clinical variables, satisfaction, and functionality among patients with spinal cord injury.

The Instituto Nacional de Rehabilitación (Rehabilitation National Institute) (INR) developed a prototype wheelchair cushion (INR cushion) designed to adjust to the anthropometry of the user's ischiogluteal area and prevent pressure ulcer formation while maintaining or promoting functionality. A prospective, longitudinal, descriptive study was conducted from February 2010 to February 2011 to evaluate the effect of using the INR cushion on clinical variables, functionality, and user satisfaction. Sixteen patients were recruited (9 male, 7 female, average age 31.8 [range 22-47] years, average body mass index 25 [range 22-34], average time in a wheelchair 10.1 [range 3-26] years) who met the study protocol inclusion criteria of being pressure ulcer-free for at least 6 months and capable of propulsion and transfer without assistance, chronic spinal cord injury (>2 years), and without chronic-degenerative diseases or cognitive problems. Each participant received the cushion for a 2-month evaluation. Eight clinical variables were assessed: trunk control, posture, spasticity, transfer capacity, comfort, skin reaction, propulsion capacity, and pressure release capacity. The clinical assessment was performed using validated scales and instruments: Modified Ashworth Scale (MAS), Functional Independence Measure™ (FIM), Norton Scale, and assessment of skin reaction. Interface pressures were measured using force sensing array, and participants completed a structured interview to assess user expectation, perceived functionality, perceived quality, and likelihood of recommending the device. Two patients withdrew due to appointment conflicts; of the remaining 14, significant differences between the user's experience with other products and the INR were found with regard to pressure redistribution (P = 0.012); all participants but 1 graded the INR as good in all interview categories. No participants developed a pressure ulcer during the study. The customized cushion was especially functional among patients with incomplete thoracic and cervical injuries, high FIM scores, and moderate levels of activities of daily living. Taller patients (P = 0.01) and patients with higher degrees of spasticity (P = 0.007) were less satisfied with functionality. The results of this study contributed to the redesign process of the cushion. These findings may be useful to establish predictors, both subjective and clinical, for patient utilization of wheelchair cushion use.