Efficacy of the Head Up collar in facilitating functional head movements in patients with Amyotrophic Lateral Sclerosis

Background: The Head Up collar is a cervical orthosis designed to be adaptable to a patient's needs using adjustable removable supports. The aim of this study was to characterise the ability of this orthosis to provide head support and facilitate the control of head movements in people living with Amyotrophic Lateral Sclerosis. Methods: Thirteen patients (6 females, age range: 45-74 years old, Amyotrophic Lateral Sclerosis Functional Rating Scale range: 13-44) with neck muscle weakness due to Amyotrophic Lateral Sclerosis were enrolled in the study. An additional inclusion criterion was the presence of enough residual muscle strength to enable the performance of the test procedure. Participants were asked to perform a series of head movements with and without wearing the collar. Two parameters (mean angular velocity and ratio of movement coupling) were extracted from recorded angular velocities, to quantify changes in the execution of the movement between the two conditions. Findings: Participants exhibited different levels of impairment in performing different movements. When wearing the collar self-selected movement velocity was preserved and significant improvement in the control of lateral flexion movement was observed (median ratio of movement coupling value reduced from 1.1 to 0.84, P = 0.013). A lower ratio of movement coupling was also observed in 4 out of 7 individuals that were fitted with anterior supports. Interpretation: The heterogeneity observed in the level of impairment and residual function highlights the need for personalized interventions. The Head Up was effective in enabling more controlled movements and maintaining the natural velocity of head movement.