# Arthroscopic Excision of a Solitary Intra-articular Osteochondroma Manifesting as a Loose Body: A Presentation of an Extremely Rare Medical Condition

## TL;DR

A rare case of intra-articular osteochondroma was found in a 55-year-old woman's knee and removed through arthroscopy.

## Contribution

This case highlights the rare occurrence of intra-articular osteochondroma presenting as a loose body.

## Key findings

- Intra-articular osteochondroma can present as a loose body in adult patients.
- Arthroscopy can effectively diagnose and remove such rare osteochondromas.

## Abstract

Osteochondroma typically has extra-articular growths at the metaphysis. Intra-articular osteochondroma is extremely uncommon. We report a case of a 55-year-old woman who had been experiencing right knee pain for the past 12 months. An arthroscopy revealed a medial meniscus tear with a loose body in the right knee. It was removed arthroscopically. Histopathology identified it as an osteochondroma. Therefore, intra-articular osteochondroma can be regarded as an uncommon cause of loose bodies in adult patients.