Arthroscopic accessibility of the talus quantified by computed tomography simulation

Area of Science:

• Orthopedic Surgery
• Anatomy
• Biomechanical Analysis

Background:

• Anterior ankle arthroscopy is the primary surgical method for osteochondral defects (OCDs) of the talus.
• The ankle joint's congruency presents challenges due to limited surgical access.

Purpose of the Study:

• To quantify the anterior arthroscopic reach of the talar dome in full plantar flexion.
• To identify factors predicting this arthroscopic reach for improved surgical planning.

Main Methods:

• A descriptive laboratory study involving CT scans of 59 ankles in full plantar flexion.
• Custom software assessed talar dome arthroscopic reach; reliability was excellent (ICC, .99).
• Multivariate regression analyzed predictive factors like plantarflexion angle, joint laxity, gender, and age.

Main Results:

• The talar dome's anterior arthroscopic reach was approximately 48% (medial and lateral domes).
• Excellent intraobserver and interobserver reliability (ICC, .99) confirmed measurement accuracy.
• Clinical plantarflexion angle was a significant predictor of increased arthroscopic reach; laxity, gender, and age were not.

Conclusions:

• Nearly half of the talar dome is accessible via anterior ankle arthroscopy.
• The degree of ankle plantar flexion is a key independent predictor of surgical access.
• Findings can optimize preoperative planning for ankle OCD treatment.