Saskia Baltrusch

171 Chapter 6 Further research with low-back patients, who have higher pain levels and cannot perform their work at the time of testing, is needed, to verify our assumption. As this study was performed in a mock up setting, results cannot be generalized directly to a real working environment. Still, the selected tasks represented a variety of tasks that can be found in many occupations. Due to the short duration of the different tasks, long-term effects of wearing the exoskeleton could not been assessed. Future research should, therefore, address the effect of long- term use of the SPEXOR exoskeleton, preferably in the real working environment. Another limitation was the difference in bending angles in the static forward bending task, which might have led to different support torque of the exoskeleton and therefore probably increased variation between subjects. Besides, the use of the User Impression Questionnaire at the end of the test battery might be skewed, as the results represented a general opinion on all tasks performed. Asking the participants’ impression after each task might lead to more task- specific results, especially those regarding the support of the exoskeleton, since the task selection did not represent an equal distribution of tasks to assess the support of the exoskeleton (n=4) and tasks to assess potential hindrance (n=8). Also, the number of participants in the allocated subgroups was rather small to test for differences in subjective non-parametric outcome measures. To get more insight into the effect of the exoskeleton on different parameters in people with low back pain, future research should increase sample size and test with low-back pain patients. 5 Conclusion The findings presented in this study demonstrate the potential of the SPEXOR exoskeleton to be used in the working environment for unloading the back and decreasing local discomfort in the low back during load-handling tasks. By implementing a clutch into the design, we resolved important problems that were encountered with previous devices, i.e. we increased versatility to use the task in a wide range of working environments. Major points that should be considered in future designs to increase user acceptance are improving the comfort, by reducing the weight and the dimension of the device, and increasing the (perceived) support. Subgroup analysis suggests that an exoskeleton has a bigger potential as a pain management intervention than as primary prevention. 6