New Treatment Approaches on the Horizon for Spastic Hemiparesis

This article presents 2 recent articles that propose novel interventions for treating spastic hemiparesis by changing biological infrastructure. In 18 patients with unilateral spastic arm paralysis due to chronic cerebral injury greater than 5 years' duration, Zheng et al transferred the C7 nerve from the nonparalyzed side to the side of the arm that was paralyzed. Over a follow-up period of 12 months, they found greater improvement in function and a reduction of spasticity compared to rehabilitation alone. Using functional magnetic resonance imaging, they also found evidence for physiological connectivity between the ipsilateral cerebral hemisphere and the paralyzed hand. In the second article, Raghavan et al examine the concept of stiffness, a common symptom in patients with spastic hemiparesis, as a physical change in the infrastructure of muscle. Raghavan's non-neural hyaluronan hypothesis postulates that an accumulation of hyaluronan within spastic muscles promotes the development of muscle stiffness in patients with an upper motor neuron syndrome (UMNS). In a case series of 20 patients with spastic hemiparesis, Raghavan et al report that upper limb intramuscular injections of hyaluronidase increased passive and active joint movement and reduced muscle stiffness. Interventions that change biological infrastructure in UMNS is a paradigm on the horizon that bears watching.