Radiographic analysis of Müller-Weiss disease

Area of Science:

• Orthopedics
• Podiatry
• Radiology

Background:

• Müller-Weiss disease (MWD) classification relies on Méary's talo-first metatarsal angle, describing navicular compression and fragmentation.
• The proposed mechanism involves talar head protrusion leading to heel varus and flatfoot ('paradoxical pes planus varus').

Purpose of the Study:

• To investigate the biomechanical changes in Müller-Weiss disease (MWD).
• To evaluate the correlation between talar head position, navicular morphology, and heel alignment.

Main Methods:

• Radiographic measurements included Méary's and Kite's talocalcaneal angles, heel offset, and navicular thickness/extrusion.
• SPECT-CT imaging assessed morphology and activity in peri-navicular joints in 45 MWD feet.
• 68 consecutive MWD feet were analyzed for navicular compression and medial extrusion at naviculocuneiform joints.

Main Results:

• Significant inverse relationships were found between Kite's angle and navicular compression/medial extrusion.
• Medial navicular extrusion strongly correlated with compression at the naviculocuneiform joints.
• Heel varus was present in only 33% of cases; heel varus with negative Méary's angle in 26%.

Conclusions:

• Lateral and inferior talar head protrusion contributes to navicular compression and medial extrusion in MWD.
• Heel varus is not a consistent finding in MWD, contradicting the 'paradoxical pes planus varus' concept.
• Surgical recommendations like lateral displacement calcaneal osteotomy should be considered cautiously due to variable heel alignment.