# Acetabular Reconstruction in a Rare Case of Ligamentum Teres Tenosynovial Giant Cell Tumour (TGCT) Causing Extensive Destruction

## TL;DR

This paper describes a rare case of a benign tumor in the hip joint that was successfully treated with surgery.

## Contribution

The paper contributes a rare case report of TGCT in the acetabulum and ligamentum teres with successful treatment via total hip arthroplasty.

## Key findings

- TGCT in the acetabulum and ligamentum teres is rare and challenging to diagnose.
- Total hip arthroplasty led to healing of the lesion in this case.
- The case highlights the importance of considering TGCT in hip joint diagnostics.

## Abstract

Tenosynovial giant cell tumour (TGCT), previously called pigmented villonodular tenosynovitis (PVNS), is a rare benign, locally aggressive condition that primarily affects the synovial lining of large joints, such as the knee, the hip, and the ankle. TGCT of the hip joint is a relatively scarce entity, and its diagnosis is often challenging. This article reports a case of TGCT affecting the left acetabulum, the left femoral head, and the ligamentum teres of the hip joint in a 39-year-old woman who presented to our clinic three months after the onset of symptoms. The patient underwent a biopsy, computer tomography (CT), and magnetic resonance imaging (MRI). All tests were inconclusive. Total hip arthroplasty (THA) was subsequently performed, leading to healing of the lesion previously present. Following surgery, a second biopsy classified this lesion as TGCT. By sharing our experience with this rare manifestation, we aim to contribute to the growing body of knowledge on the diagnosis and management of TGCT, specifically when it occurs in the hip joint.