Deltoid (triangular)-shaped anterior cruciate ligament that caused notch impingement: a report of two cases

Area of Science:

• Orthopedic Surgery
• Sports Medicine
• Anatomy

Background:

• Anterior cruciate ligament (ACL) injuries are common in sports medicine.
• Anatomical variations of the ACL can lead to intra-articular impingement.
• Impingement syndromes can cause pain and dysfunction in the knee joint.

Purpose of the Study:

• To report two unique cases of ACL tibial insertion anomalies.
• To describe the resulting impingement at the intercondylar notch, patellofemoral sulcus, and PCL.
• To present the surgical management and outcomes for this rare condition.

Main Methods:

• Case report of two patients with symptomatic knee pain.
• Diagnostic imaging (MRI/arthroscopy) to identify ACL morphology and impingement.
• Surgical intervention involving ligamentoplasty and excision of impinging ACL tissue.

Main Results:

• Identification of a wide, deltoid-shaped ACL tibial insertion in both cases.
• Impingement observed at the intercondylar notch, inferior patellofemoral sulcus, and PCL.
• Successful surgical excision of impinging ACL portions, restoring normal tibial insertion width.

Conclusions:

• A wide, triangular ACL tibial insertion is a rare anatomical variant causing knee impingement.
• Surgical management involving targeted excision can effectively treat this condition.
• Restoring normal ACL anatomy is crucial for alleviating impingement symptoms and improving knee function.