The disease is slowly progressive and compatible with a normal life span. Asymptomatic affected members of a family have no restrictions. In a survey, 61 of 126 affected adults were currently working, only 9 needed adjustments for disease-related handicaps, and 85% considered their jobs satisfying (Wavers et al 1993).
Medical complications are few. Twenty percent of patients (or fewer) will eventually use a wheelchair. Clinically significant respiratory failure occurs in about 1% of patients (Wohlgemuth et al 2004). Predisposing factors include wheelchair dependence, pelvic girdle weakness, kyphoscoliosis or lumbar lordosis, and pectus excavatum. Pregnancy is usually tolerated well, but some women later have more difficulty caring for children (Rudnik-Schoneborn et al 1997; Ciafaloni et al 2006).