In the malalignment test for deformity analysis, the mechanical lateral distal femoral angle (mLDFA) has a mean normal value of 87 degrees. An mLDFA of 78 degrees indicates:

• A Normal distal femoral alignment
• B Proximal tibial deformity
• C Varus deformity of the distal femur
• D Valgus deformity of the distal femur ✓

Explanation

The mLDFA is the angle between the femoral mechanical axis line and the distal femoral joint line, normally 85 to 90 degrees. A reduced value means the joint line tilts outward relative to the mechanical axis, defining distal femoral valgus. A value greater than 90 degrees would indicate distal femoral varus. The medial proximal tibial angle, normally about 87 degrees, assesses the proximal tibia, so a tibial deformity would not alter the mLDFA.

Reference: Principles of Deformity Correction, 1st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.