Manual ability and upper limb performance in nonambulatory stage of Duchenne muscular dystrophy

The functional use of the upper extremities in daily living activities has become important in the later ages with the increasing life expectancy of patients with Duchenne muscular dystrophy (DMD). This study aimed to assess manual ability and upper limb performance of nonambulatory children with DMD, and to determine their relationship with factors that might affect ability and performance.

Manual ability was determined via the ABILHAND-Kids questionnaire and upper limb performance was assessed with the Performance of Upper Limb (PUL) test. Possible related factors such as functional level, steroid usage, upper limb range of motion (ROM), thumb opposition, upper limb muscular strength, and grip strength were evaluated. Correlations of related factors with manual ability and upper limb performance were analyzed.

The mean age of 23 nonambulatory DMD children was 13.04±1.39 years. Moderate impairments were determined according to the ABILHAND-Kids and PUL, with scores of 26.30±10.74 and 46.22±15.02, respectively. The functional level, steroid usage, duration of wheelchair use, upper extremity ROM, and global upper limb muscle strength of children were weak-to-strongly correlated with at least one score of ABILHAND-Kids and PUL (P<0.05).

Children with DMD may already have severe proximal and mid-level upper extremity involvement, even reflected in distal functions, at the time when they progress to the nonambulatory stage. Besides muscular strength, many related factors should be taken into account for therapists to assess and treat upper limb performance at later stages of DMD.