In ACL reconstruction your surgeon will transfer tissue from another part of your knee (“autograft”), or occasionally from a cadaver donor (allograft) to where your natural ACL was. Simply “fixing” the torn ACL back to where it was before does not typically work well, given current technologies.
There are many scientific articles that debate the advantages and disadvantages of different donor sites for ACL reconstruction. Taking tissue from the Hamstrings or Patellar tendon are by far the most common practices in Canada. Dr. Cayen’s current approach is guided by the scientific literature currently available and his surgical experience.
Most patients prefer the hamstring tendon method since it hurts less and has fewer serious complications than patellar tendon autografts. The disadvantage of hamstring tendon autograft is that historically, it tends to loosen up a little bit with time when measured with special machines. The large majority of ACL reconstructions performed by Dr. Cayen at this time are completed using this method. A technical video on how Dr. Cayen performs a hamstring tendon ACL reconstruction can be found here.
This method takes piece of bone from the knee cap (patella), a piece of bone from the leg (tibial tubercle) and one third of the tendon that connects the two pieces of bone (patellar tendon). It is slightly stiffer tissue than the hamstring when tested in the knee using special machines. Risks of this method include more pain in the immediate period after the surgery, pain with kneeling, and breaking (fractures of) the kneecap. In long term follow-up, patients who have had BTB autografts typically have more knee pain around the kneecap and have a higher chance of getting knee arthritis compared patients who have had hamstring autografts.
In older patients (over 40 years old, without background arthritis), Dr. Cayen tends to use allograft ACL reconstruction. “Allograft” means that the tissue used comes from a cadaver donor. These pieces of tissue are sterilized and stored in a freezer. This graft is then used to reconstruct your ACL. As you get older, your own tendons start to get weak and thin. The allografts used are stronger than the grafts harvested from older patients.
Commonly there are meniscus tears that are associated with ACL tears. Dr. Cayen will address these during your ACL reconstruction surgery.
If a meniscus repair was not necessary during your surgery, (eg no meniscus work was required, or you required removal of some meniscus material) you will be allowed to put full weight on your leg after the surgery. Most patients experience discomfort in the knee as well as quadriceps weakness after ACL reconstruction. For that reason, you will likely need crutches for approximately two weeks after the procedure.
If a meniscus repair was required, you will be allowed to place only 20 to 30 pounds of pressure on your foot while walking for 6 weeks. You’ll need crutches for 6 weeks, if you have a meniscus repair.
The decision to perform meniscal trimming or a meniscus repair depends on the configuration of your meniscus tear at the time of surgery.
See section on Meniscus Tears for more information
Patient who have ACL reconstruction typically have it done under a general anaesthetic and leave hospital the same day.