There are usually 2 areas where a surgeon can take a graft to replace your ACL. The two areas are your patellar tendon or your hamstring tendons. If this is new information to you, refer to our previous post on some details about ACL surgery here. When reading the differences listed below it is important to remember that your surgeon will choose the graft site for your ACL surgery. The good news is that our app, Curovate, for ACL rehabilitation has a protocol for hamstring tendon or patellar tendon grafts here.  

Hamstring Graft Surgery (HT)  

Patellar tendon also called Bone-Patellar-Bone Surgery (BTB)  

1. The operation takes more time and the tourniquette, which is a device used during surgery to limit blood flow in the leg, is on for longer[ 2]    

1. The knee is stiffer after surgery[ 2] 2. The knee moves more freely front and back, when tested using a KT-1000 Arthrometer machine[ 2], which is a device that measures front and back movement of your lower leg compared to your thigh. 2. More knee pain when kneeling on the ground[ 3] 3. Over a period of 15 years after surgery there were more reinjuries reported.[ 3] 3. Over a period of 15 years after surgery more stiffness and difficulty straightening the knee was reported[ 3]. 4. The need to do another surgery to address issues with the first surgery is called a revision surgery. The revision rates, for hamstring graft surgeries increases by 0.65% within 1 year and by 4.45% within 5 years[ 4]. 4. Revision rate after 1 year is 0.16% and revision rate after 5 years is 3.03% for patellar tendon graft surgeries[ 4]. 5. Hamstring muscle power reduced by 15%[ 1]. Muscle power is the maximum force you can apply in as short a time as possible. 6. Muscle strength reduces by 11% when straightening the knee[ 2]. Muscle strength is how much force a muscle can produce in a maximal effort. 7. There is more instability in the knee when force is applied[ 2]. Instability is undesirable movement in a joint.

References:

[1]: Ageberg, E., Roos, H. P., Silbernagel, K. G., Thomeé, R., Roos, E. M., akademin, S., . . . Göteborgs universitet. (2009). Knee extension and flexion muscle power after anterior cruciate ligament reconstruction with patellar tendon graft or hamstring tendons graft: A cross-sectional comparison 3 years post surgery. Knee Surgery, Sports Traumatology, Arthroscopy, 17(2), 162-169.

2]: Beynnon, B. D., Johnson, R. J., Fleming, B. C., Kannus, P., Kaplan, M., Samani, J., & Per Renstrom. (2002). Anterior cruciate ligament replacement: Comparison of bone-patellar tendon-bone grafts with two-strand hamstring grafts A prospective, randomized study. The Journal of Bone & Joint Surgery, 84(9), 1503-1513.

[ 3]: Leys, T., Salmon, L., Waller, A., Linklater, J., & Pinczewski, L. (2012). Clinical results and risk factors for reinjury 15 years after anterior cruciate ligament reconstruction: A prospective study of hamstring and patellar tendon grafts. The American Journal of Sports Medicine, 40(3), 595-605.

[ 4]: Rahr-Wagner, L., Thillemann, T. M., Pedersen, A. B., & Lind, M. (2014). Comparison of hamstring tendon and patellar tendon grafts in anterior cruciate ligament reconstruction in a nationwide population-based cohort study: Results from the danish registry of knee ligament reconstruction. The American Journal of Sports Medicine, 42(2), 278-284.