# Scapholunate Dissociation due to an Atypical Biomechanical Mechanism in Arm Wrestling: A Case Report

## TL;DR

A 28-year-old arm wrestler developed scapholunate dissociation due to an unusual injury mechanism during a match.

## Contribution

This case report highlights arm wrestling as a novel cause of scapholunate ligament injury.

## Key findings

- Scapholunate dissociation occurred due to forced elbow extension during an arm wrestling match.
- The injury mechanism differs from typical causes, concentrating force on the wrist rather than the humerus.
- Early diagnosis is crucial for arm wrestlers with persistent wrist symptoms.

## Abstract

Scapholunate ligament injuries are not uncommon in hand surgery, but they are not described in the sport of arm wrestling.

The patient was a 28-year-old man who experienced wrist pain when he was about to lose an arm wrestling match. Since then, he has had persistent clicking in his right wrist, which was found to be due to scapholunate dissociation. The reason for scapholunate dissociation rather than a humeral shaft fracture in our patient may be a reduction in torque on the humerus due to forced elbow extension, which could be seen in a losing player at the end of the match. This position could concentrate the reaction force on the wrist rather than on the humerus.

Arm wrestling should be recognized as a potential cause of scapholunate dissociation due to its atypical injury pattern, necessitating early diagnosis. Furthermore, the unique biomechanics of arm wrestling warrant attention in orthopedic and surgical literature.