# Atraumatic Shoulder Dislocation Revealing a Brain Tumor: A Case Report

**Authors:** Kazuhiro Ikeda, Shotaro Teruya, Hiromitsu Tsuge, Ryunosuke Watanabe, Shinzo Onishi

PMC · DOI: 10.7759/cureus.98472 · Cureus · 2025-12-04

## TL;DR

A man with a non-traumatic shoulder dislocation was found to have a brain tumor causing seizures, highlighting the need to consider neurological causes in such cases.

## Contribution

This case report emphasizes the importance of neurological evaluation in patients with unexplained shoulder dislocations.

## Key findings

- The patient's shoulder dislocation was linked to a brain tumor causing seizures.
- Surgical resection of the tumor and antiseizure therapy led to seizure freedom and good shoulder recovery.
- Orthopedic surgeons play a key role in identifying underlying neurological conditions.

## Abstract

Non-traumatic shoulder dislocation may occasionally result from seizure-related disorders, and, in rare cases, from underlying brain tumors. We report a 23-year-old man who presented with anterior shoulder dislocation without apparent trauma. Computed tomography revealed a large Hill-Sachs lesion, a bony Bankart lesion, and a coracoid process fracture - findings inconsistent with a low-energy mechanism of injury. Because the injury occurred during sleep, an epileptic seizure was suspected. Further neurological evaluation identified focal epilepsy originating from the right frontoparietal region, and brain magnetic resonance imaging revealed a tumor in the right frontal lobe. Surgical resection confirmed an isocitrate dehydrogenase-mutant, Central Nervous System World Health Organization grade 2 astrocytoma. Following tumor resection and antiseizure therapy, the patient remained seizure-free while continuing conservative management for shoulder instability. Both the bony Bankart lesion and the coracoid process fracture had achieved bony union, the American Shoulder and Elbow Surgeons score reached 100, and functional recovery was excellent.

This case highlights the importance of considering seizure-related or intracranial pathology in atraumatic shoulder dislocation and underscores the pivotal role of orthopedic surgeons in the early recognition of underlying central nervous system disease.

## Linked entities

- **Diseases:** astrocytoma (MONDO:0019781), epilepsy (MONDO:0005027)

## Full-text entities

- **Diseases:** epileptic seizure (MESH:D004827), seizure (MESH:D012640), related (MESH:D019973), astrocytoma (MESH:D001254), tumor (MESH:D009369), Shoulder (MESH:D000070599), central nervous system disease (MESH:D002493), Shoulder Dislocation (MESH:D012783), Bankart lesion (MESH:D000070896), coracoid process fracture (MESH:D019534), focal epilepsy (MESH:D004828), trauma (MESH:D014947), Brain Tumor (MESH:D001932)
- **Species:** Homo sapiens (human, species) [taxon 9606]

## Full text

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## Figures

5 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12764389/full.md

## References

19 references — full list in the complete paper: https://tomesphere.com/paper/PMC12764389/full.md

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Source: https://tomesphere.com/paper/PMC12764389