Long-term outcome of division of the C8 nerve root for spasticity of the hand in cerebral palsy

Cadaveric Feasibility Study on Modified Contralateral C7 Nerve Transfer for Targeted Recovery in Hemiplegic Arms

BACKGROUND

Contralateral cervical seventh (cC7) nerve to C7 transfer has been proven effective for treating spastic upper limb. However, for those whose major impairment is not in the C7 area, cC7 nerve transfer to other nerves may achieve a better outcome. The aim of this study was to explore the optimal surgical approach for transferring cC7 to 1 or 2 nerves in a cadaveric study, and to evaluate possible applications for patients with hemiplegia.

METHODS

Modified cC7 transfer to 1 (5 procedures) or 2 nonadjacent (3 procedures) nerve roots was proposed, and success rates of direct coaptation through 2 surgical approaches-the superficial surface of longus colli (sLC) and the deep surface of longus colli (dLC) approach-were compared. The length, diameter, and distance of relevant nerves were also measured in 25 cadavers.

RESULTS

Compared with the sLC approach, the distance of the dLC approach was 1.1 ± 0.3 cm shorter. The success rates for the sLC and dLC approaches were as follows: cC7 to C5 surgery, 94%, and reached 98%; cC7 to C6 surgery, 54% and 96%; cC7 to C7 surgery, 42% and 94%; cC7 to C8 surgery, 34% and 94%; cC7 to T1 surgery, 24% and 62%; cC7 to C5C7 surgery, 74% and 98%; cC7 to C6C8 surgery, 54% and 98%; and cC7 to C7T1 surgery, 42% and 88%.

CONCLUSIONS

The dLC approach greatly improved the direct coaptation rate for cC7 nerve transfer. The modified cC7 nerve transfer procedures are technically feasible for further application in clinic.

Reconstruction of paralyzed arm function in patients with hemiplegia through contralateral seventh cervical nerve cross transfer: a multicenter study and real-world practice guidance

BACKGROUND

A previous randomized controlled trial showed contralateral seventh cervical nerve (CC7) cross transfer to be safe and effective in restoring the arm function of spastic arm paralysis patients in a specified population. Guidance on indications, safety and expected long-term improvements of the surgery are needed for clinical practice.

METHODS

This is a retrospective, multicenter, propensity score-matched cohort study. All patients registered between 2013 and 2019 with unilateral spastic arm paralysis over 1 year who were registered at one of five centers in China and South Korea were included. Patients received CC7 cross transfer or rehabilitation treatment in each center. Primary outcome was the change in the upper-extremity Fugl-Meyer (UEFM) score from baseline to 2-year follow-up; larger increase indicated better functional improvements.

FINDINGS

The analysis included 425 eligible patients. After propensity score matching, 336 patients who were 1:1 matched into surgery and rehabilitation groups. Compared to previous trial, patient population was expanded on age (< 12 and > 45 years old), duration of disease (< 5 years) and severity of paralysis (severe disabled patients with UEFM < 20 points). In matched patients, the overall increases of UEFM score from preoperative evaluation to 2-year follow-up were 15.14 in the surgery group and 2.35 in the rehabilitation group (difference, 12.79; 95% CI: 12.02-13.56, p < 0.001). This increase was 16.58 at 3-year and 18.42 at 5-year follow-up compared with the surgery group baseline. Subgroup analysis revealed substantial increase on UEFM score in each subgroup of age, duration of disease, severity of paralysis and cause of injury. No severe complication or disabling sequela were reported in the surgery group.

INTERPRETATION

This study showed that CC7 cross transfer can provide effective, safe and stable functional improvements in long-term follow-up, and provided evidences for expanding the indications of the surgery to a wider population of patients with hemiplegia.