Interactions of physical, emotional, cognitive and behavioural impairments after severe closed head injury (CHI) remain poorly understood. A 47-year-old man was referred to our department 13 months after a severe CHI. He demonstrated severe left hemiplegia and disabling orthopaedic complications (left hip infectious arthritis, after surgical treatment for heterotopic ossification). His hip was blocked and extremely painful. He was totally dependent for daily-life activities (Functional Independence Measure (FIM) score = 18). Moreover he exhibited severe cognitive and behavioural troubles, which had been stable for many months beforehand, e.g. complete disorientation for time and place, major memory disorders, agitation, anxiety, depression, irritability, disinhibition, aggressiveness and lack of initiative. Pain disappeared within a few weeks after treatment. Progressively, functional improvement occurred (sitting position, transfers, walking between parallel bars). The FIM score increased to 63. Aggressiveness, irritability and agitation disappeared. Surprisingly, neuropsychological assessment demonstrated parallel improvement of cognitive functions, especially in regard to orientation, and to a lesser degree attention and memory. Such an observation should encourage use of active treatment of physical disabilities, even in patients presenting with an apparently poor cognitive prognosis at a late stage of severe CHI.