A cadaver study on preserving peroneal nerves during ankle arthroscopy.

Background: Ankle arthroscopy is an important diagnostic and therapeutic procedure, but neurovascular injury remains a disadvantage. By understanding the anatomy of the superficial peroneal nerve (SPN) and deep peroneal nerve (DPN) the risk of nerve injury can be minimized.

Methods: Thirty-four lower limbs from 17 cadavers were dissected to find the safest anatomical points easily during arthroscopy.

Results: There was a single branch of the SPN in eight of 34 specimens (23.5%); type 1), two branches in 18 (52.9%; type 2), three branches in six (17.7%; type 3) and four branches in two specimens (5.9%; type 5) at the level of the talocrural (TC) joint. The closest SPN branch to lateral border of the TC joint was 14 +/- 8.4 mm. There was no branch of the SPN or DPN medial to the extensor hallucis longus tendon in any specimen. The DPN bifurcation was 6.5 mm proximal to the TC joint in a single specimen (2.9%) and 14.5 +/- 5.5 mm distal to TC joint in 26 specimens (76.5%). In four specimens (11.8%), the DPN bifurcation was at the same level with the TC joint. In three specimens (8.8%), there was no bifurcation of the DPN.

Conclusions: From this study the anatomic landmarks defining the medial midline portal are safely away from the SPN and DPN and their respective branches. Clinical studies are needed to define its safety during ankle arthroscopy.

Clinical Relevance: This study proves that the medial midline portal is the best portal for the anterior arthroscopic procedures.