Summary
Description
Tug lesion, also known as avulsive cortical irregularity is an overuse injury that occurs in the knees of children. It can be mistaken for a tumor.
People and Age
Children between 11 and 14, depending on bone age, get this lesion.
Symptoms and Presentation
Symptoms are knee pain with athletic activity
Brief description of the xray
On xrays, at the distal posterior medial end of the femur, just above the growth plate, a cortical irregularity is seen.
Brief desc of tx
Treatment is rest and observation
Tumor Type
Benign or Malignant
Body region
Most Common Bones
Location in bone
Position within the bone
Tumor behavior
Tumor density
Complete Information on this Tumor
Introduction and Definition
This overuse injury occurs when a child is intensely active, in running sports or basketball or similar sports, and the medial head of the gastrocnemius muscle, which attaches along with distal medial portion of the femur just above the femoral growth plate, as a result of repetitive forceful muscle traction at the muscle-bone junction, causes a reactive process in the surface of the femur which can be apparent on x-rays.
Incidence and Demographics
In children and adolescents. Most cases occur in very active children, typically children who are participating in multiple sports are participating in frequent activities over a period of months. Typically both sides are somewhat involved a the one side may be more symptomatic.
Symptoms and Presentation
Patients present with knee pain and a bone lesion. One or both sides may be symptomatic.
X-Ray Appearance and Advanced Imaging Findings
On xrays, at the distal posterior medial end of the femur, just above the growth plate, a cortical irregularity is seen, either with lucency, reactive bone formation, sclerosis, or a combination of these.
MRI Findings
The lesion is hypo intends on T-1 weighted images, and hyper intense on T2 weighted images, with a dark rim on both sequences. These lesions take up F-18 FDG and are thus PET positive.
CT Findings
An irregular lesion at he posterior medial border is seen, which may have ossification in the muscle insertion seen as overlying bone and reactive change in the nearby cortex.
Special and Unusual Features
This lesion has been mistaken for a malignancy, both on radiographs, as well as on histopathology. In patients with worrisome radiographic findings, or worrisome clinical history such as a history of other malignancy, additional concern arises because avulsive cortical irregularity lesions take up F-18 FDG and are thus PET positive.
