Background: “Row-a-boat” phenomenon (RBP) is a
spontaneous upper-body movement in patients with advanced Duchenne
muscular dystrophy (DMD), when sitting upright supported by a belt
around the body in a wheelchair. However, the role of RBP has not been
Objectives: To support the hypothesis that
RBP is an abnormal pattern of respiration to compensate for the
atrophied respiratory muscles in advanced DMD.
methods: Age, degree of ventilator dependency, and blood gas and
spirometry values of 12 patients with spontaneous RBP were compared to
those of 8 patients without RBP. All patients were men, and all
exhibited a comparable level of motor function (unable to ambulate).
Spirometry was undertaken with an ambulatory pneumotachograph in six
patients with RBP in two conditions: sitting with RBP and sitting
without RBP. In the latter condition, because a patient’s shoulders,
neck, and head were manually restricted, RBP was prevented.
Results: We found that the patients with RBP were older
(mean, 25.98 years vs 19.84 years), more dependent on mechanical
ventilation (13.96 h/d vs 4.31 h/d), and had lower FVC and percentage
of FVC (511.3 mL vs 762.5 mL and 13.37% vs 20.11%, respectively) than
those without RBP. We also found that the frequency of RBP was
identical with tidal breathing, and FVC was increased by 50.8% by
simply allowing RBP.
Conclusion: We conclude that RBP
is a respiratory movement to compensate for the atrophied respiratory
muscles in advanced DMD.