WDS is named after Dr. Worster-Drought who first described it in 1956.It is a form of cerebral palsy in which the main effect on movement, is on the control of muscles which normally move the lips, jaw, tongue, palate, back of the throat (pharynx) and upper gullet (oesophagus or food pipe). Any number of these areas can be affected to variable degrees, and the children may have problems with eating, drinking, swallowing, dribbling and/or speech. Like many forms of cerebral palsy, the condition is complex and can be associated with difficulties in many areas (e.g. learning, behaviour, epilepsy). This means that the children can appear very different from each other, and often their main difficulties can be in the associated areas, rather than predominantly focused on the oral problems. Thus children with WDS can come to the attention of a variety of different specialists, (speech therapist, teacher, educational psychologist, G.P., paediatrician… ). As the condition is not well known, it can take some time before the whole picture is recognised and WDS diagnosed, enabling the child to receive the multifaceted support they need.
WDS is thought to be due to an abnormality in the area of brain that is responsible for the sophisticated control of movement of the muscles around the mouth and throat. In some cases an abnormality can be seen in this area on a brain scan. This abnormality is thought to occur very early in the development of brain of the baby during the first third of pregnancy. There is usually no obvious cause in the pregnancy or birth. In a minority of children, there is a family history of WDS, although which gene is involved, or how it has an effect, is not understood. From the range of difficulties encountered in children with WDS, it seems likely that there may be subtle changes in other areas of the brain would explain why these children are vulnerable to epilepsy, learning difficulties, slow motor development… etc. Given that the abnormality appears to occur very early in the formation of the brain, and that this process is very complex and vulnerable, this is not too surprising.
WDS is a clinical diagnosis, which means that it is made on the basis of the history and examination. The core features are the difficulty with movements around the mouth and throat from an early age (usually below 2 years) and a brisk jaw jerk. For example, many children have difficulty in waggling the tongue from side to side, or even in and out. Most children have difficulty in additional areas, as previously mentioned. There is no specific test, although there are a number of investigations that can be helpful, and may be arranged by the child’ doctor.