Subtalar joint configuration on weightbearing CT scan

Area of Science:

• Orthopedics
• Radiology
• Anatomy

Background:

• Previous subtalar joint morphology studies relied on cadaveric or unloaded imaging.
• In vivo and loaded imaging parameters differ significantly, limiting diagnostic value.
• Subtalar joint morphology impacts its function.

Purpose of the Study:

• Determine subtalar joint posterior facet morphology using loaded CT.
• Describe configurations in asymptomatic patients.

Main Methods:

• Weightbearing CT scans of 59 asymptomatic patients.
• Measurement of posterior facet shape and subtalar vertical angle (SVA) in 3 coronal planes.

Main Results:

• Posterior facet was concave (88%) or flat (12%).
• Posterior facet orientation was valgus (90%) or varus (10%) in the middle coronal plane.
• SVA varied across different coronal planes.

Conclusions:

• Understanding subtalar joint morphology is crucial.
• This knowledge can improve reconstructive hindfoot surgery planning and reduce failures.