Misdiagnosed cartilaginous PCL avulsion in young children

Abstract

Posterior Cruciate Ligaments injuries are rare in children and usually due to bony avulsion fractures or midsubstance tears. This study focused on cartilaginous avulsions initially misdiagnosed despite of MRI assessment. Two 6-year-old boys had cartilaginous avulsion fracture injury at the femoral attachment of the PCL. One had associated medial meniscal lesion and was reinserted. The other conducted to non-union. MRI second lecture reveals an original description with nail-biting sign on cartilage surface of anterior notch, and a close PCL angle without anterior tibial translation. No bone bruise was associated. Similarly, to ACL cartilaginous tibial avulsions, PCL cartilaginous femoral avulsions are underdiagnosed. When knee hemarthrosis occurs under the age of nine, clinician and radiologist should be aware that cartilaginous avulsion of ACL and PCL also could be the main pattern of lesion.

Posterior Cruciate Ligament Femoral Avulsion Fractures in Pediatric Patients

“…In 2021, Pacull et al identified 14 patients younger than 9 years with PCL cartilaginous injuries (cartilaginous avulsion or intrasubstance tear) 8 . In pediatric and adolescent patients, tibial PCL avulsions are more common than femoral PCL avulsions 6 .…”

“…In patients younger than 14 years, most PCL femoral avulsions described are cartilaginous, and several have been reported in children aged 3 to 7 years 7,8 . Five bony femoral avulsion fractures are reported in the literature; however, they were in patients 8 years or older, and their mechanisms of injury were typically secondary to high-energy trauma 9-13 .…”

“…The amount of displacement should be considered, and in pediatric populations, successful nonoperative treatment has been reported when there is less than 7 millimeters (mm) of displacement of the avulsed fragment. 5 In patients younger than 14 years, most PCL femoral avulsions described are cartilaginous, and several have been reported in children aged 3 to 7 years 7,8 . Five bony femoral avulsion fractures are reported in the literature; however, they were in patients 8 years or older, and their mechanisms of injury were typically secondary to high-energy trauma [9][10][11][12][13] .…”

X-Sens Inertial Sensor Technology-Based Rehabilitation on a Patient With Posterior Cruciate Ligament Avulsion Fracture and Shaft of Femur Fracture: A Case Report

“…Particularly in frontal aggression in the flexed knee posture or hyperextension, the PCL is vulnerable to injury. The PCL is involved in 4%-38% of knee injuries observed in emergency rooms, indicating the clinical importance of this ligament in preserving knee joint integrity [7]. Avulsion fractures of the tibial insertion caused by the posterior cruciate ligament (PCL) are extremely uncommon in pediatric patients.…”