# Combined nerve and tendon transfer (CNaTT) for grasp and release function in patients with tetraplegia: a matched prospective pilot study

## TL;DR

A new surgical approach combining nerve and tendon transfers may improve hand function in tetraplegic patients compared to traditional methods.

## Contribution

The study introduces a two-stage combined nerve and tendon transfer technique to enhance grasp and release function in tetraplegia.

## Key findings

- Adding a nerve transfer allowed more patients to achieve normal one-handed hand opening.
- The study group showed superior grasp and release ability and pinch opening.
- No significant differences were found in grip strength or activity performance between groups.

## Abstract

Traditional single-stage tendon transfer procedures in patients with tetraplegia are designed to restore active pinch and grasp function. However, digital extension is usually achieved by wrist tenodesis. More recently, nerve transfer has allowed potential restoration of digital extension. This matched observational pilot study compares clinical outcomes after traditional tendon transfers vs. a study group using two-stage using combined nerve and tendon transfer.

Eighteen patients in the traditional tendon transfer control group and 18 patients in the combined nerve and tendon transfer group using a supinator branches to posterior interosseous nerve (S-PIN) transfer were compared. Primary outcomes include hand opening capacity, using the cylinder test. Secondary outcomes include muscle strength, first web space opening, grip and pinch strength, grasp and release ability, and activity performance.

Analyses indicated that adding a nerve transfer allowed more patients to achieve normal one-handed hand opening, although this difference was not statistically significant. Secondary outcomes revealed superior grasp and release ability and pinch opening in the study group; however, there were no notable differences in grip strength and activity performance between the groups.

Adding a S-PIN nerve transfer appears to enhance grasp function in the tetraplegic limb when combined with established tendon transfer techniques. For individuals with tetraplegia, the capacity to use single hand grips is particularly significant, as it allows the other arm to stabilize and compensate for limited core balance. More participants with a longer follow-up are needed to fully demonstrate the superiority of combined nerve and tendon procedures.

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