Laura Peeters

40 | Chapter 2 Future directions Future studies should take into account the following factors. First, standardized clinical measures are missing, especially a valid trunk control scale that is applicable to all patients with a flaccid trunk. Although trunk control scales do exist, they are mostly developed for a specific patient group or unsuitable for patients that fully depend on a seated position. The Trunk Control Measurement Scale (TCMS) [50] might be a suitable trunk control scale which assesses both static and dynamic trunk control while sitting. However, it has been validated only in children with CP who can sit without trunk or feet support for at least 30 minutes. To use this scale in all patients, it must first be validated in other patient groups. The scale should also be validated for patients who already have difficulties with sitting without trunk or feet support. For children with CP who cannot sit independently, the Segmental Assessment of Trunk Control [51] could be a suitable scale to assess discrete levels of trunk control. It could be used complementary to the TCMS, but it needs to be validated in other patient groups as well. Importantly, future studies should adequately discriminate different age groups as the interactions between trunk, head and UE control mature during childhood and are influenced by trunk length. Lastly, future studies should include other patient groups with a flaccid trunk, such as patients with NMD and spinal dysraphism/spina bifida, with the aim to discriminate generic from disease-specific mechanisms of trunk and head instability and of reaching incapacity. Especially if generic mechanisms can be identified, it will be possible to develop common intervention strategies to support postural stability and optimize seated task performance across different patient groups.