LMNA-related congenital muscular dystrophy: potential impact of corticosteroid treatment on contracture progression and motor function

Patients with LMNA-related congenital muscular dystrophy (L-CMD) are characterized by the early development of retractions. However, their pattern of onset, progression and impact on motor function are not well defined. To describe the onset, progression and pattern of joint contractures and motor function in a group of patients with L-CMD treated and untreated with corticosteroids. This is a retrospective study in a group of 10 cases with Dropped head syndrome (L-CMD-Dhs). All patients presented before 20 months of age, and started walking between 16-20 months. Moreover, patients were divided into two groups according to the presence of ongoing treatment with corticosteroids (prednisone 1- 0.75mg/kg/day daily dose). Patients with Dhs phenotype without corticosteroid treatment (n= 5, mean age at review: 21 years (range: 20-24), presented in 100% of the cases contractures before the age of 10 years in all the joints studied, as follows in chronological order (mean age in years; range): Achilles (3.4; 1.5-5), hip (6.1; 5-8), elbows (6.3; 2.5-8), knee (6; 4.5-8), mean age of gait loss was 7.4; years (range: 5-11). In the group receiving corticosteroids (n= 5; mean age 9 years; range 8-10), contractures were observed in the following chronological order (mean age of onset in years; range): ankle (3.8;1-7), hip (5.3;4-7), elbows (6.3;4-7), knee (7.6;7-9); none of the patients had lost autonomous ambulation at last examination included in the study and 2 patients did not develop retraction of knees or hips. When comparing the two subgroups, a significant (p<0.05) difference in walking ability was observed in favour of the patients who received corticosteroids. These preliminary data suggested that larger cohorts of patients should be investigated to better understand the impact of retractions on motor function and the potential effect of corticosteroid treatment on the progression of retractions. It is important to establish standards of care, assessment and treatment of retractions in this group of patients. Patients with LMNA-related congenital muscular dystrophy (L-CMD) are characterized by the early development of retractions. However, their pattern of onset, progression and impact on motor function are not well defined. To describe the onset, progression and pattern of joint contractures and motor function in a group of patients with L-CMD treated and untreated with corticosteroids. This is a retrospective study in a group of 10 cases with Dropped head syndrome (L-CMD-Dhs). All patients presented before 20 months of age, and started walking between 16-20 months. Moreover, patients were divided into two groups according to the presence of ongoing treatment with corticosteroids (prednisone 1- 0.75mg/kg/day daily dose). Patients with Dhs phenotype without corticosteroid treatment (n= 5, mean age at review: 21 years (range: 20-24), presented in 100% of the cases contractures before the age of 10 years in all the joints studied, as follows in chronological order (mean age in years; range): Achilles (3.4; 1.5-5), hip (6.1; 5-8), elbows (6.3; 2.5-8), knee (6; 4.5-8), mean age of gait loss was 7.4; years (range: 5-11). In the group receiving corticosteroids (n= 5; mean age 9 years; range 8-10), contractures were observed in the following chronological order (mean age of onset in years; range): ankle (3.8;1-7), hip (5.3;4-7), elbows (6.3;4-7), knee (7.6;7-9); none of the patients had lost autonomous ambulation at last examination included in the study and 2 patients did not develop retraction of knees or hips. When comparing the two subgroups, a significant (p<0.05) difference in walking ability was observed in favour of the patients who received corticosteroids. These preliminary data suggested that larger cohorts of patients should be investigated to better understand the impact of retractions on motor function and the potential effect of corticosteroid treatment on the progression of retractions. It is important to establish standards of care, assessment and treatment of retractions in this group of patients.