Tips for Knee Arthroscopy Don Johnson / Jeff Abrams





The Set Up


The set up shows the correct knee marked with my initials with a marking pen, the low profile leg holder, and the tourniquet. The end of the table can be broken to allow posterior access or the leg is lowed over the side of the table.





The Portals


The portals are the high antero-lateral portal, (to avoid the fat pad), the routine medial portal, (in the middle of the soft spot), and the low accessory medial portal, (next to the patella tendon and just above the anterior horn of the medial meniscus.)





The high lateral portal is made with the knee flexed at 90* over the side of the bed. The arthroscopy blunt trochar is inserted, and moved to the supra patellar pouch as the knee is extended.

• The Routine Diagnostic Examination.
  
  It is important to follow a routine with the diagnostic examination. If you do, you will not have the experience of getting to the dictation area and not being able to dictate the findings in the lateral compartment. This happens when you look in the medial side, do the menisectomy, and stop. Get in the habit of doing a complete examination of the knee before operating.
  
  
  
• The patellofemoral joint.
  
  The scope visualizes the supra patellar pouch for synovitis, loose bodies, and plica.
  
  The articular surface of the patella and femoral trochlea is examined for chondromalacia.
  
  The scope is then moved to the medial gutter looking for the medial plica, loose bodies and synovitis
  
  The medial compartment is examined for medial meniscal tears, and the femoral and tibial articular surfaces. The foot and ankle are placed on the surgeons hip to produce a valgus stress to open up the medial compartment. See the tips on the tight knee.
  
  The scope is then moved around the edge of the articular surface of the notch, above the ligamentum mucusom and fat pad. The knee should be flexed to 90* over the side of the bed. On the lateral side of the fat pad the anterior cruciate ligament is examined. On the medial side the posterior cruciate is examined. If this area has to be examined in detail, the ligamentum and fat pad may have to be removed with a shaver. This may cause bleeding, so the diagnostic examination should be completed first.
  
  The lateral compartment is examined by placing the scope against the lateral side of the anterior cruciate ligament, and placing the knee in the figure four position. The ankle should be crossed over the opposite shin. This will produce enough varus to open the lateral compartment. This compartment is examined for torn lateral meniscus, articular surface chondromalacia of the femur and tibia, and loose bodies in the popliteal recess. The lateral gutter is examined for synovitis and loose bodies. The lateral recess is a favorite hiding place for loose bodies.
  
  
• Posterior compartment
  
  Medial. The scope is placed in the lateral portal, a valgus stress is applied, and the scope advanced under the posterior cruciate ligament, and over the medial tibial spine , into the posterior compartment. The compartment is massaged with the finger externally to milk any loose bodies into view.
  
  Lateral. The scope is placed in the medial portal, the knee in the figure four position, and the scope advanced under the anterior cruciate ligament, over the lateral spine, and into the posterior compartment. Again the compartment may have to be milked from the external surface to make loose bodies visible.
  
  If a separate portal is required to remove the loose bodies, use a spinal needle to set up the correct angle, cut the skin and spread the tissues with a hemostat.
  
  
  
  
  The postero-lateral compartment examination
  
  
  
  The tips for visualizing the posterior horn of the medial meniscus in the tight knee are:
  
  
  Stress Relaxation of the medial ligament. When gradual stress is applied to the medial ligament over several minutes, the medial joint will begin to open up. Do not apply the pressure quickly, or the medial ligament will rupture, be patient!
  
  
  
  
  
  The knee is placed on the hip and a gradual valgus force is applied.
  
  Use of the accessory medial portal for the arthroscopy and the routine medial portal for the basket forceps.
  
  A good tip to see the tight posterior horn of the medial meniscus is to put the scope in the low accessory medial portal. ( see the picture above ) The instruments are placed in the normal medial portal. This may cause a little instrument crowding, but will allow better visualization.
  
  
  The tight lateral compartment:
  
  
  
  
  The foot of the heel is lifted up to increase the varus on the knee.