# Posterior Interosseous Neuropathy with Peripheral Dystonia: A Case Report

## TL;DR

A 62-year-old man experienced finger drop and dystonia-like movements due to posterior interosseous neuropathy, with partial recovery and persistent thumb abnormalities.

## Contribution

This case report highlights a rare association between posterior interosseous neuropathy and peripheral dystonia.

## Key findings

- The patient showed posterior interosseous neuropathy with dystonia-like finger movements.
- Muscle weakness improved within two weeks, but thumb abnormalities persisted.
- Persistent thumb posture may indicate pre-existing motor control issues contributing to dystonia.

## Abstract

Posterior interosseous neuropathy is an uncommon cause of peripheral dystonia.

A 62-year-old man awakened and noticed right finger drop. A neurological examination revealed posterior interosseous neuropathy with dystonia-like finger movements. Abnormal movements were predominantly observed in the right thumb, ring finger, and little finger. Within 2 weeks, the muscle weakness in the right fingers had completely improved. However, a brief abnormal posture of the right thumb was persistent.

The residual abnormal posture of the right thumb may reflect pre-existing motor control abnormalities, which may have contributed to the onset of posterior interosseous neuropathy-associated peripheral dystonia.