Medial collateral ligament lengthening by standardized pie-crusting technique: A cadaver study

Area of Science:

• Orthopedic surgery
• Biomechanics
• Knee ligament reconstruction

Background:

• Medial collateral ligament (MCL) lengthening is crucial in knee surgery.
• Pie-crusting (PC) is a technique using perforations to expand tissue.
• Standardization of MCL PC for controlled joint line opening is needed.

Purpose of the Study:

• To codify and evaluate the standardized medial collateral ligament (MCL) pie-crusting (PC) technique.
• To assess the reliability and reproducibility of MCL PC for medial femorotibial (MFT) joint line lengthening.
• To determine the effect of MCL anterior bundle (AB) preservation or sectioning on MFT joint line distraction.

Main Methods:

• Thirty-one cadaver knees underwent dissection with cruciate ligament and meniscus resection.
• Medial collateral ligament (MCL) pie-crusting (PC) was performed using a 19-G needle with standardized perforations.
• Knees were allocated to anterior bundle (AB) sparing (AB+) or sectioning (AB-) groups, with 80N distraction applied to the medial femorotibial (MFT) joint line.

Main Results:

• The mean medial femorotibial (MFT) joint space increased by 3.16±2.70mm in the AB- group versus 0.18±0.18mm in the AB+ group.
• A total of 25 perforations were made in the AB+ group and 16 in the AB- group.
• No medial collateral ligament (MCL) tears occurred in either group.

Conclusions:

• Medial collateral ligament (MCL) pie-crusting (PC) is a reliable and reproducible technique for controlled joint line lengthening.
• Combining MCL PC with anterior bundle (AB) sectioning significantly increases medial femorotibial (MFT) joint line distraction.
• The standardized MCL PC technique allows for measured joint line opening without risk of MCL tear.