Posterior arthroscopic approach to the ankle: an anatomic study

Area of Science:

• Orthopedic Surgery
• Anatomy
• Minimally Invasive Procedures

Background:

• Arthroscopic ankle surgery is increasingly common for intra-articular and extra-articular pathologies.
• Posterior approaches are essential for certain ankle conditions but carry risks to neurovascular structures.
• A novel posterior arthroscopic technique utilizing a modified posteromedial portal and the flexor hallucis longus (FHL) tendon has been described.

Purpose of the Study:

• To anatomically verify the safety of a new posterior arthroscopic ankle technique.
• To assess the proximity of critical neurovascular structures to the modified posteromedial portal.
• To evaluate the risk of iatrogenic injury during the described arthroscopic procedure.

Main Methods:

• Anatomic dissection of 10 below-knee amputation specimens (4 fresh, 6 fresh-frozen).
• Performance of the novel posterior arthroscopic technique, leaving instruments in situ.
• Measurement of distances between neurovascular structures and the posteromedial portal, including a comparison with a more proximal portal.

Main Results:

• No injuries to the neurovascular bundle were observed during instrument insertion or posterior compartment procedures.
• The modified posteromedial portal was located an average of 13.3 mm from the posterior tibial nerve and 17.3 mm from the posterior tibial artery.
• A 1 cm more proximal portal placement was found to be 2.9 mm closer to nervous structures.

Conclusions:

• The described posterior arthroscopic ankle technique demonstrates a low risk profile for injury to surrounding neurovascular structures.
• The flexor hallucis longus (FHL) tendon serves as an effective landmark for safe navigation within the posterior compartment.
• This technique is considered relatively safe for addressing both intra-articular and extra-articular ankle pathologies.