Nerve transfer surgery improves limb activity after traumatic spinal injury
Nerve transfer surgery elicits significant improvements in limb activity in patients suffering from traumatic spinal injury, according to a recent prospective case series.
“This project is the first to comprehensively examine outcomes for early, multiple nerve transfer surgery in the upper limbs of people with tetraplegia following traumatic spinal cord injury, and is the largest prospective series of nerve transfers reported in this population to date,” said researchers.
Sixteen traumatic spinal cord injury patients, corresponding to 27 limbs, underwent a total of 59 nerve transfers. Tendon transfers were also performed in 12 limbs (10 participants). Surgeries were performed a mean of 10 months after injury. Two participants were lost to follow-up while one died, though from causes unrelated to the procedure. [Lancet 2019;doi:10.1016/S0140-6736(19)31143-2]
In the overall population, there was a significant improvement in median webspace opening, growing from 12.0 mm at baseline to 95.0 mm at follow-up (p=0.0001). This effect was stronger in those who received nerve transfers alone (10.0 to 110.0 mm; p=0.0019) than in those who underwent both nerve and tendon transfers (20.0 to 92.5 mm; p=0.028).
Researchers also observed a significant 24-month increase in scores in the action research arm test, both in the overall sample (16.5 to 34.0; p<0.0001) and in the subgroups (nerve transfer alone: 15.5 to 32.0; p=0.0015; nerve and tendon transfers: 18.0 to 37.5; p=0.012).
The same was true for scores in the grasp release test (total sample: 35.0 to 125.2; p<0.0001; nerve transfer alone: 29.8 to 89.3; p=0.0010; nerve and tendon transfer: 39.4 to 142.9; p=0.017).
Researchers likewise reported improvements that exceeded minimal clinically important threshold in total score in the spinal cord independence measure (31.2 to 39.3) and the mobility in the room and toilet subscale (2.9 to 5.2).
“Nerve transfer surgery is a safe and reliable addition to the surgical options for upper extremity reconstruction in tetraplegia and leads to functional improvements similar to those of tendon transfer surgery,” said researchers. “Consideration should be given to the inclusion of nerve transfer donors in the International Classification for Surgery of the Hand in Tetraplegia.”
Of the 20 participants who were surveyed for procedure satisfaction, 70 percent (n=14) were satisfied with the outcomes. This was higher among those who received nerve vs tendon transfers (75 percent vs 63 percent). Only one patient who underwent nerve transfer was dissatisfied with the outcome. None regretted having the surgery.
“Participants appreciated the different styles of hand functionality afforded by nerve transfers for grasp and pinch on one side and tendon transfers on the other. Enhanced patient selection based on the learnings from this project could improve results further,” said researchers.
“It remains to be seen whether function and strength in muscles reanimated by nerve transfers continue to improve beyond 24 months postsurgery,” underscoring the need for more long-term studies, they added.