Dt. Palmer et al., BOTULINUM TOXIN TREATMENT OF LUMBRICAL SPASTICITY - A BRIEF REPORT, American journal of physical medicine & rehabilitation, 77(4), 1998, pp. 348-350
Botulinum toxin A has been used to treat wrist and finger spasticity m
ainly through injection of the forearm flexor muscles. This case study
describes its first reported use in managing spastic lumbricals of th
e hand. A 19-year-old male had significant flexion deformity and hyper
tonicity of the left wrist and hand, particularly the second through f
ifth metacarpophalangeal joints, after traumatic brain injury. By usin
g the 0-4 Ashworth scale, spasticity of the lumbricals across the seco
nd to fourth metacarpophalangeal joints was rated 2, with persistent c
lonus of the finger flexors as confirmed by electromyography to the mi
ddle and ring fingers, even after botulinum toxin A injection of the f
lexor digitorum sublimis and profundus muscles. By using the electromy
ography-guided technique, botulinum toxin A was injected into the firs
t lumbrical of the index finger (12 units), second and third lumbrical
s of the middle and ring fingers, respectively (15 units each), and fo
urth lumbrical of the little finger (10 units). At follow-up, clinical
and electromyographic examination revealed a significant reduction in
tone and clonus of the injected lumbricals. Ashworth scores of the lu
mbricals from the index to little finger improved to 1. Botulinum toxi
n A injection of the lumbricals can be beneficial in managing spastici
ty of these muscles. It is well tolerated and effective at doses of 10
to 15 units. Lumbrical injection of botulinum toxin A is a useful adj
unct in our percutaneous armamentarium for managing the spastic hand.