Surgical techniques | Anterior arthroscopy

Surgical Procedure

In this picture the starting situation is depicted. It concerns a left foot of which the medial and lateral malleolus are marked.
The anteromedial portal is made first. It is located medial from the anterior tibial tendon, lateral to the medial malleolus and at the level of the ankle joint. To assess the level of the ankle joint, the 'soft spot' needs to be found. This is done by palpation the distal tibia with a thumb, and from there on moving distally.
The soft spot is found. To verify this location, when moving the ankle in dorsiflexion the thumb gets locked into the joint at this level.
Then, the anterior tibial tendon is located.
This tendon moves laterally on dorsiflexion. Since portals are always made in the dorsiflexed position to prevent it from iatrogenic cartilage damage, this should be taken into account.
The anterio tibial tendon is marked. The fluent line indicates the tendon in the neutral position, the dotted line is the anterior tibial tendon in the dorsiflexed position. The anteromedial portal is situated just medial from this tendon (black marker) at the level of the ankle joint.
Portals we use for anterior ankle arthroscopy. the two standard protals we use are the anteromedial and anterolateral portal. The anterolateral portal is made under direct vision, just lateral to the peroneus tertius tendon. Two additional portals can be made during the procedure, depending on the indication. These are the inferior anteromedial- and lateral portals.
The anteromedial portal is made first. In dorsiflexion, a longitudinal incision is made through the skin only and the subcutaneous layers and joint capsule are bluntly dissected with a mosquito clamp (this picture).
In the dorsiflexed position, an arthroscopic shaft with blunt trocar (4.5mm) is introduced.
When the trocar is touching the underlying bony joint line, it is very gently pushed further into the anterior working area, towards the lateral side. Now the 4.0 mm 30 degree arthroscope can be introduced.
The direction of view is routinely to the medial side. The anterior joint line is now visible. We prefer this grip on the scope: with the thumb on the light source the direction of view can easily be adjusted; the longest finger in on the distal part of the scope and the skin for ultimate stability and ease to push in- and retract the scope.
The lateral joint line is visualized. The scope should be pointing in this direction to make the lateral portal under direct vision.
Again, the lateral portal is made in the dorsiflexed position. All instruments should be introduced in this position, to prevent iatrogenic cartilage damage. The surgeon can use his/ her body for this to be able to freely use both hands for arthroscopy.
To make the anterolateral portal, a spinal needle is inserted under direct vision at the level of the joint line, just lateral form the peroneus tertius tendon (or if not present the extensor digitorum tendon).
A vertical stab incision is made at this level. Attention should be paid to not hit the superficial peroneal nerve.
With a mosquito clamp the subcutaneous layers and ankle capsule are bluntly dissected.
Now the anterior working area can be inspected, for which we use a probe.
From here on many different patholgies can be identified and treated, which are discussed in the corresponding chapters. Here we see the beginning of removing the soft tissue surrounding an anterolateral osteophyte on the tibia, using a 5.5 mm bonecutter shaver. This procedure can be found in chapter 'Anterior Impingement: Osteophyte Anterior Tibia'.
Overview of important landmarks for anterior ankle arthroscopy.
Additional portals are the inferior anteromedial (encircled)- and inferior anterolateral portal.
The inferior anterolateral portal is made under direct vision, with the scope in the anteromedial portal, aiming distally. The direction of view is to proximal.
A spinal needle is introduced just in front of the tip of the medial malleolus.
The skin incision is made in line with the fibres of the deltoid ligament.
With a mosquito clamp the subcutaneous layers and capsule are divided.
Now any instrument can be introduced. In this case, we used a 5.5 mm bonecutter shaver to work on a bony rim of the distal medial malleolus.
The scope is still in the anteromedial portal, and the bonecutetr shaver is in the inferior anteromedial portal. Shaving the medial malleolus is much easier from this position.
From this inferior anteromedial portal shaving all the way to posterior is possible when necessary.

Pearls & Pitfalls


The portals should be made in the neutral position or in slight dorsiflexion, to minimize the risk of damage to the underlying structures. The anteromedial portal is regarded to be relatively safe, nevertheless neurovascular complications have been reported.

Introduction of the instruments through the anteromedial and anterolateral portal must be done with the ankle in dorsiflexion. In this position the nerves and vessels are not in tension, resulting in a minimal risk of iatrogenic damage. Moreover this forced dorsiflexed position is the best prevention for iatrogenic cartilage damage.

The superficial peroneal nerve is visible in 40% of patients. To reduce the risk of damage it should be localized when possible (plantarflexion and inversion).

Osteophytes can be removed more easily in dorsiflexion, since it will increase the anterior working area in combination with the saline used for irrigation.


1. careful_introduction_instrument.jpg  2. correct_introduction_instrument.jpg  3. SPN_extview.jpg

1. Be Careful

2. Correct introduction of spinal needle. With the ankle in dorsiflexion, the weight-bearing cartilage of the talus cannot be damaged.

3. The superficial peroneal nerve (indicated with arrows (left) and in yellow (right)).



The saphenous nerve and great sapheneus vein are potentially at risk when making the anteromedial portal. The superficial peroneal nerve is at risk in creating the anterolateral portal. To prevent damage:

1. make the incision through the skin only;

2. use blunt mosquito clamp to spread the soft tissue and to enter the joint cavity;

3. use only blunt instruments to enter the joint cavity;

4. introduce your instruments and scope with the ankle in the slightly or fully dorsiflexed position.