No one likes to experience complications, but the surgeon who is prepared to deal with the potential complications will rise above the rest. Remember:

"It's not if,

but when,

and how bad."

The discussion of the complications will be to present the problem, give a solution to the problem and finally offer a prevention of the problem.

Click on the photos to view a large picture. Use the browser back button to return to complications in ACL Reconstruction

Pre-op Considerations

• Patient Selection
  
• Timing of Operation
  
• Immature Athlete
  
• Medial Compartment Osteoarthritis Associated with Anterior Cruciate Ligament Deficiency
  

Patellar Tendon Harvest
Semi-t Graft Harvest
Dropped Graft
Tibial Tunnel Anterior
Anterior Femoral Tunnel
Posterior Blow Out of Femoral Tunnel
Over drilling K-Wire
Neuro-Vascular Injury






Pre-op Considerations
Attention must be paid to several pre-op details to avoid complications with anterior cruciate reconstruction.

Patient Selection
The non-compliant patient who returns to sport too early is at risk to rupture the graft. The opposite type of patient, that is, the nervous, anxious red head, or the extremely apprehensive patient, is at risk to develop stiffness. If these patient profiles are recognized, appropriate preventive measures can be taken.

Timing of Operation
The acute knee, with a marked limited range of motion, and induration, should be treated conservatively, until this knee becomes less inflamed. Operation in this acute situation often results in post op stiffness and difficulty in obtaining range of motion.

Immature Athlete
The pre-teen athlete with an anterior cruciate ligament tear is a rare clinical situation, and is difficult to manage. The natural history of the immature athlete with an anterior cruciate ligament tear is pessimistic.

If the youngster cant give up sports, then an anterior cruciate ligament reconstruction should be carried out. The operation should avoid injury to the epiphysis. The tibial tunnel should be drilled in the center of the epiphysis, avoiding the tibial tubercle. The semi-tendinosus graft should be taken over the top, or through a femoral tunnel and fixed with a endo button. With these precautions, injury to the growth plate is rare.

It is important to x-ray the young patient to asses the physis around the knee.

Medial Compartment Osteoarthritis Associated with Anterior Cruciate Ligament Deficiency
The association of medial compartment osteoarthritis and the anterior cruciate deficient knee is a common clinical situation.

In the early phase the anterior cruciate ligament reconstruction should be the principle procedure, with an arthroscopic debridement of the medial compartment.

When the medial compartment wear is more severe, and the patient is still complaining of giving way, still has a positive pivot shift test, has a moderate degree of clinical varus in the standing position, then the ligament reconstruction should combined with a high tibial osteotomy.

When the medial compartment wear is marked, the varus is moderately severe, the patient lacks full knee extension, has a negative pivot shift test, then the high tibial osteotomy should be the only procedure carried out.






Problem
Patellar Tendon Harvest

• Patellar Fracture
  
• Small / thin / fractured bone plugs
  
  

Solution

• Patellar fracture open reduction and internal fixation
  
• Small thin bone plug
  

• Bone graft the plug, piggy back fashion, using coring reamer in tibia
  
  

Use Krackow sutures, and tie over buttons




Prevention

• Use saw like a cast saw - 90* to cut cortex, 45* to depth of 6-7 mm
  
• Avoid deep V - 6-7 mm in depth
  

• Gently lift out with osteotome - make a flat base to bone plug.
  
  

Problem
Semi-t Graft Harvest
This photo shows the amputate tendon that was caused by not cutting the bands to the gastro.

• Graft cut off short
  
• Small size
  
  
  

Solution

• change graft source- patellar tendon / synthetic
  
• augment with gracilis
  
• augment with LAD
  
• accept the small graft
  
  

Prevention

• Careful harvest technique
  
• Cut bands to gastrocnemius
  
  
  

This shows what happens when the band is not cut, and the stripper is advanced against the band. The tendon becomes angled and may be cut off short.




This photo shows the bands to the gastroc that must be cut to advance the stripper up the tendon.







Problem
Dropped Graft
The rule in our operating room is the one who drops the graft, donates his own graft. (harvested under local anaesthesia of course)



Solution

• Change graft to semi-t or patellar tendon from same side
  
• Cleanse graft
  
• Hibiclens soaking
  
• Serial dilutions - triple antibiotics
  
  
  

Prevention

• Pass with towel clip in a basin
  
• No one touches graft
  
• Watch out for tendon sticking to glove.
  
  

It always drops between the back table and the OR table.









Problem
Tibial Tunnel Anterior
Result - Notch impingement

This photo shows the guide inserted too anterior on the footprint of the anterior cruciate ligament on the tibia.



Solution

• Make the notch bigger.
  
• Chamfer back of tunnel.
  
• This option is better since there will be no impingement of the graft in the notch.
  
  

Prevention

• Use K-Wire and re-position.
  

Extend the knee with K-Wire in notch to see if there is enough clearance for the graft in the notch.

• Use landmarks - 7 mm anterior to PCL
  
  

The inside landmarks are 7 mm anterior to the posterior cruciate ligament and in the midline.

This shows the position of the k-wire in the midline and 7 mm anterior to the posterior cruciate ligament.







Problem
Anterior Femoral Tunnel

• Result - Graft failure in flexion
  
  

This x-ray shows the screw position anterior in the femur. This represents an anterior femoral tunnel.




Solution

• Slightly anterior
  
• Trough over the over the top position
  
• Far anterior
  
• Make another tunnel behind bone graft anterior tunnel or fill the old tunnel with a bioscrew
  
  
  

Prevention

• Guide
  
• Flex knee >70*
  
• Visualize posterior fringe
  
• Use guide to place k-wire 7 mm over the top, at 1 or 11 oclock
  
  

This drawing demonstrates the use of the Bullseye guide placed in the over the top position with the knee flexed at 90*.


Use push/pull drilling to make an initial footprint. If this is not blowing out the posterior wall or is not too anterior then the drill bit can be advanced up to into the femur for 35 mm.






Problem
Posterior Blow Out of Femoral Tunnel
This photo shows the thin posterior wall of the femoral tunnel. This would not be strong enough to insert a interference screw. The screw would force the bone plug of the graft out the back, and loss of fixation would result.



Solution

• Change from interference screw to endo button fixation
  
• Use the old 2 incisions technique with interference screw from outside in
  
• Advance screw and graft farther up into the femoral tunnel
  
  
  

Prevention

• Flex knee to 70-90*
  
• Visualize posterior fringe
  

• Use push/pull drilling to make an initial footprint.
  
  

If this is not blowing out the posterior wall or is not too anterior then the drill bit can be advanced up to into the femur for 35 mm.







Problem
Over drilling K-Wire

• Recognize the failure of the drill to progress
  
  
  
  
  
  

Solution

• Recognize Early
  
• Change K-wire
  
  
  

Prevention

• Watch the drill, not TV monitor
  

• Piston drilling to follow the k-wire
  
  
  

Problem
Neuro-Vascular Injury

This is a post op picture that you never want to see.

Solution

• Early Recognition
  
• Prompt Surgical Repair
  
  

Prevention

• Vessel lies directly behind the posterior horn of the lateral meniscus
  
• Visualize posterior fringe
  
• Avoid burrs, shavers, osteotomes in the posterior compartment
  
• Use a curette to remove the bone and soft tissue posteriorly
  
• Never operate in a red-out
  
  

The safest instrument in the posterior aspect is a curette.