Article

Although calf muscle spasticity is often treated with botulinum toxin
type-A, the effects on balance and gait are ambiguous. Hereditary spastic
paraplegia is characterized by progressive spasticity and relatively mild muscle
weakness of the lower limbs. It is therefore a good model to evaluate the
functional effects of botulinum toxin type-A.
DESIGN: Explorative pre-post
intervention study. SUBJECTS: Fifteen subjects with pure hereditary spastic
paraplegia. METHODS: Patients with symptomatic calf muscle spasticity and
preserved calf muscle strength received botulinum toxin type-A injections in each
triceps surae (Dysport(R), 500-750 MU) followed by daily stretching exercises (18
weeks). Before intervention (T0), and 4 (T1) and 18 (T2) weeks thereafter, gait,
balance, motor selectivity, calf muscle tone and strength were tested. RESULTS:
Mean comfortable gait velocity increased from T0 (0.90 m/s (standard deviation
(SD) 0.18)) to T1 (0.98 m/s (SD 0.20)), which effect persisted at T2, whereas
balance and other functional measures remained unchanged. Calf muscle tone
declined from T0 (median 2; range 1-2) to T1 (median 0; range 0-1), which effect
partially persisted at T2 (median 1; range 0-2). Calf muscle strength did not
change. CONCLUSION: Botulinum toxin type-A treatment and subsequent muscle
stretching of the calves improved comfortable gait velocity and reduced muscle
tone in patients with hereditary spastic paraplegia, while preserving muscle strength. Balance remained unaffected.

Langue : ANGLAIS