Gerdy's tubercle: the lighthouse to the knee.

Area of Science:

• Orthopedic Surgery
• Anatomy

Background:

• Gerdy's tubercle is a critical landmark for knee surgical approaches.
• Accurate identification can be challenging due to soft tissue swelling, obesity, or injury.

Purpose of the Study:

• To establish a reliable and reproducible method for identifying Gerdy's tubercle using surrounding anatomical structures.
• To overcome challenges in landmark identification during knee surgery.

Main Methods:

• Anatomic cadaver study involving 24 lower extremities.
• Systematic measurement from a defined intersection point to Gerdy's tubercle.
• The intersection point was determined by lines connecting corners of a box formed by the tibial tubercle, inferior patellar pole, and fibular head.

Main Results:

• The mean distance from the defined intersection point to Gerdy's tubercle was 2.58 ± 2.01 mm.
• No significant difference was found between right and left lower extremities (P = 0.84).
• The method demonstrated a narrow range (0-8 mm), indicating high reproducibility.

Conclusions:

• A novel, reliable, and reproducible method for identifying Gerdy's tubercle has been established.
• This technique utilizes the intersection of lines derived from the tibial tubercle, inferior patellar pole, and fibular head.
• The identified point serves as a consistent landmark for surgical knee approaches.