P.10.5 The effect of the limitation of ankle joint’s movement on the walking performance in neuromuscular diseases

Abstract

Although the adverse effects of muscle weakness on the performance are well known in neuromuscular diseases, the importance of the distribution of weakness has not been investigated in detail. In this study, we investigated the spatial distribution of the weakness impact on walking parameters. Totally 40 children in early functional levels (with Brooke lower extremity scale stage 1–3) are included in this study where 20 of them have been diagnosed with Neuropathy (mean ages: 12.9 ± 3.3 years) with distal muscle weakness and the other 20 have been diagnosed with Duchenne Muscular Dystrophy (DMD) (mean ages: 9 ± 3.1) with proximal muscle weakness. The limitations in ankle joint were measured with goniometer. The walking ability was evaluated with the 6 min walking test (6MWT). The limitations in ankle joints’ movement were measured as 17.5 ± 8.7° and 20.9 ± 8.4° on the right and left sides, respectively in patients with neuropathy while these measurements were 20,4 ± 10,2° and 8,6 ± 7,8° on the right and left sides in DMD patients. There were not any significant difference between the groups (p > 0,05). The result of the 6MWT were recorded as 358.8 ± 75 m for the patients with neuropathy and 349.7 ± 77.1 m for the patients with DMD (p > 0.05). There was a negative correlation between the right (r = −0.579, p = 0.007) and left (r = −0.445, p = 0.049) ankle dorsiflexion limitations and 6MWT results in the group with proximal muscle weakness. The limitation of ankle joint may disrupt the standing balance and accelerate the loss of ambulation. Our study showed that limitation of ankle joint movements in patients with proximal muscle weakness could affect functional performance more negatively than patients with distal muscle weakness.