Spinal cord tethering is commonly seen in patients with syringomyelia. A tethered spinal cord occurs when scar tissue forms and holds the spinal cord to its surrounding soft tissue membrane and dura. It has significant effects on spinal cord movement, CSF flow and extracellular fluid flow resulting in mobility issues and intramedullary pressure changes when exerting certain movements (Klekamp & Samii 2002). Untethering of the spinal cord is used to prevent or revise neurological or orthopedic sequelae.
In a pre-post trial, Falci et al. (2009) reported that spinal cord untethering resulted in improvement in neuropathic pain, sensory and motor functions. Falci et al. (1999) found untethering and shunt tube placement resulted in a significant improvement in light touch, pinprick and motor scores in SCI patients without previous syringomyelia surgery. Two case series (Lee et al. 2001; Lee et al. 2000) assessed the result of untethering only, shunting only, and untethering and shunting in a group of SCI individuals with syringomyelia. Both studies found that more patients in the untethering only group had improved spasticity than patients in the other groups. Motor function and sensory loss improvement was common in all three groups. However, the shunting group only demonstrated more improvement in gait than the untethering group.
There is level 4 evidence (from one pre-post and three case series studies: Falci et al. 2009; Falci et al. 1999; Lee et al. 2000; Lee et al. 2001) that untethering improves motor and sensory loss.
There is level 4 evidence (from two case series studies: Lee et al. 2000; Lee et al. 2001) that untethering improves spasticity in more patients with syringomyelia than shunting.