A Pertinent Guide To Basic Ankle Arthroscopy
Surgery in general seems to gravitate toward smaller and less invasive procedures. Obviously, the less tissue disruption that occurs during surgery, the less risk one has of postoperative complications such as scarring, infections, delayed healing, etc. Although this may not be true with every surgical advance, arthroscopy has revolutionized the treatment of joint disorders and allowed many of these common complications to be almost entirely eliminated. Increasing indications for this technique include the treatment of subtalar, calcaneal cuboid and first metatarsal disorders. However, for the purposes of this column, I’d like to offer a closer look at the basics of ankle arthroscopy. In my opinion, the purpose of ankle arthroscopy can be divided into diagnosis and treatment. As modalities such as MRI and CT continue to improve, there seems to be less of a need for direct arthroscopic visualization when it comes to making a simple diagnosis of ankle disorders.1 However, in the face of persistent pain and non-definitive imaging studies, arthroscopy can provide surgeons with an excellent opportunity to inspect the joint closely and arrive at an accurate diagnosis. The role of arthroscopic treatment is almost limitless. The most common indications I find for this procedure include synovitis, chondral lesions, loose intraarticular fragments, exostosis and chronic or acute instability. Numerous other indications such as severe arthrosis and fractures exist, but these involve more complex arthroscopic maneuvers and are beyond the scope of basic arthroscopy.2 Addressing Patient Placement And Ease Of Access Typically, you would give the patient a general anesthetic to employ a thigh tourniquet. You can complete this procedure with only intravenous sedation and local anesthetic, but I have found this to be more difficult due to having to place the tourniquet on the “high ankle” or calf. It’s also easier to assess instability of the ankle, especially following acute injury, when the patient is completely anesthetized. An arthroscopy is more difficult without using a tourniquet for hemostasis, due to hemorrhage constantly obscuring the field of vision. When treating patients who may benefit from not using a tourniquet, such as those who have a history of deep venous thrombosis, judicious use of local anesthetic with epinephrine will significantly lessen this problem. One may use both around the portals as well as intraarticularly. In a basic arthroscopic approach, you would place the patient in a supine position. Some surgeons prefer to place the affected side in a knee holder and drop the end of the operating table. This allows you to be seated during the procedure. I am inclined to have the patient’s heel approximately 3 to 4 inches off the table and to stand during the arthroscopy. This allows me to maneuver the ankle in any direction and to stabilize both arms against my own torso. Even with the patient in a supine position, you can easily access the posterolateral portal if the table is angled or if you place a pad below the hip on the operative side. This simply exaggerates internal rotation of the limb. In order to use this adjunctive portal to its full advantage, the patient may need to be further down on the table. Otherwise, the arthroscopic equipment will continue to contact the table and limit your movement. You may need to seek alternative positioning based on the patient’s particular pathology and your ability to address it.3 What You Should Know About Portal Placement Portal placement is the most important part of the procedure. Poorly placed incisions will limit access to the joint and increase the risk of neurovascular or tendinous injury. When approaching the anterior aspect of the ankle, it is best to identify topical landmarks. Typical marking should identify the anterior tibial tendon, the extensor hallucis longus tendon and the anterior tibial artery. One should do this prior to joint distention since the areas marked may become distorted. At this point, you would employ either a two- or three-portal approach. I choose to use an anteromedial and anterolateral approach. The anterocentral approach is an acceptable portal as well, but carries the added risk of being very close to the neurovascular bundle. Although you should be cautious with this approach, it is an excellent portal for viewing the ankle.