Page 212 - Functional impairment and cues for rehabilitation of head and neck cancer patients -

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Chapter 9
the program increased from 19% up to 79%. With respect to the clinical results, we found that none of the patients were feeding tube dependent and only 4% had experienced pneumonia in the past six months. However, still a substantial proportion of the patients experienced dysphagia (25%), trismus (20%), and speech problems (58%) at one-year post-treatment. A comparison with other studies was not feasible given the heterogeneity of patient populations and outcome measures. However, it was clear that, despite the efforts of the implementation of the rehabilitation program, a substantial proportion of patients still experience functional limitations. This suggests there is either still room for further improvement of rehabilitation approach or some sequels cannot be prevented.
Several years ago, the idea emerged that the TheraBite, a tool to treat and prevent trismus, could be modified to train swallowing musculature. Kraaijenga et al. developed the Swallow Exercise Aid (SEA) as a tool to not only perform preventive but also reactive (swallowing) exercises (9, 10). From these first two successful SEA studies, questions remained regarding several aspects of an optimal (preventive) rehabilitation protocol. For example, optimal training duration, exercise frequency, and the need for maintenance therapy are still unsettled. Also, although improvement of function was seen and the effectiveness of the principle was suggested, it was yet unclear whether the muscles hypothesized to be targeted, indeed were trained, and whether the combination of exercises within the protocol was targeting all relevant muscles to improve swallowing function.
Therefore, we performed a biomechanical study on muscle activation during treatment with the SEA versus conventional exercises using a non-invasive Magnetic Resonance Imaging technique (Chapter 6) (11). This study revealed that the suprahyoid, infrahyoid, and sternocleidomastoid muscles were activated during both SEA and conventional exercises (i.e., conventional effortful swallow, Shaker and Masako), but that in addition to those muscle groups, during SEA exercises also the lateral pterygoid muscles were activated. Therefore, we were able to conclude that besides laryngeal elevation also mouth opening mechanisms were targeted. Tongue and pharyngeal muscles also play an important role in swallowing and other functions of the head and neck area. However, in our MRI study we could not conclude that these muscles were activated as well, although this was most likely due to the relatively small muscle size, which resulted in less precise measurements. However, given the improved tongue strength in the previous two studies on the effectiveness of the SEA by Kraaijenga et al. (9, 10), and the use of pharyngeal muscles during the effortful swallow, we still assume that these muscles are targeted by the SEA, as well. To be really certain, more invasive techniques are probably needed, such as EMG, to visualize activation of these muscles. The use of EMG needles in often high dose RT areas was deemed undesirable and not justified for the purpose of this study.
Post-treatment functional status can be improved by the previously discussed active preventive rehabilitation strategies, but also by strategies regarding tube feeding before and during treatment. A long-standing discussion exists on the appropriate timing of feeding tube