When anterior cruciate ligament (ACL) reconstruction surgery is required, due to a full thickness tear of the ACL, patients need information about surgical options. This should include what type of tendon graft the orthopedic surgeon recommends to achieve optimal results. Richard Cunningham, MD, a Board Certified Orthopedic Surgeon and Knee and Shoulder Sports Medicine Specialist, has more than 20 years of experience in ACL reconstruction surgery. Here, find Dr. Cunningham’s discussion comparing the quad tendon graft versus the patellar tendon graft for ACL reconstruction.
What are ACL Graft Choices?
There are several tendon graft options for patients undergoing anterior cruciate ligament (ACL) reconstruction. The first choice is deciding whether the graft is harvested from the patient (autograft) or harvested from a cadaver (allograft). Several factors affect the choice of which graft to use, particularly patient age and activity level. In the past, many surgeons utilized allografts for most patients undergoing ACL reconstruction, but these were found to fail at a high rate, especially in those under 30 years of age. Therefore, in the last decade, autografts have been more frequently used, as they yield better results compared to an allograft. For this discussion, the patellar tendon graft and quad tendon graft are compared.
Here is Dr. Cunningham’s discussion on the hamstring tendon graft versus the quad tendon graft for ACLR.
Patellar Tendon Graft
This graft is taken from the central portion of the patellar tendon. At least the central third (and oftentimes more) of one’s patellar tendon is removed. However, because the patellar tendon is a short tendon, a one inch long section of bone from the knee cap and a one inch long section of bone from the tibia are removed along with the tendon portion. Patellar tendon grafts have long been used for ACL reconstruction, and they have a history of long term success. The graft has been used in young athletes who compete in high level cutting and pivoting sports as well as in professional athletes with good results.
However, there are some downsides to a patellar tendon graft. Because of the fact that a section of the patella is removed, there is a higher incidence of pain when kneeling and this pain can be permanent. Women who have not undergone ACL surgery are already at a higher risk of having pain around the patella, and this pain can be more frequent and worse for female athletes who have undergone a patellar tendon ACL reconstruction. Because bone from the patella is removed, the patella is weakened, and there is a somewhat higher risk of sustaining a patella fracture if someone were to fall onto their knee cap after surgery. There can be some residual numbness along the anterolateral aspect of the knee due to the incision cutting some small, superficial sensory nerve fibers. Finally, the incision size is larger for a patellar tendon ACL surgery than with other graft options leaving a longer scar.
Quadriceps Tendon Graft
Harvesting the central part of the quadriceps tendon is a very good graft choice, and Dr. Cunningham’s preferred graft for the last 10 years for several reasons. The quad tendon is nearly twice as thick as a patellar tendon, thus making it stronger. The quad tendon is a longer tendon than the patellar tendon, and thus there is no need to take a section of bone from the patella or tibia, resulting in less kneeling pain and less patellar fracture risk. The quad tendon can also be harvested through a smaller incision compared to a patellar tendon harvest.
Anterior cruciate ligament reconstruction with quadriceps tendon autograft is a great autograft option for many patients. For over a decade, The Knee Doctor, Richard Cunningham, MD, has utilized the quadriceps tendon for ACL reconstruction almost exclusively in his practice. Numerous orthopedic studies support the quad tendon graft technique compared to both patellar tendon and hamstring tendon autografts for ACL reconstruction.
There are many benefits of a quad autograft:
- High success rate with a very low (<5%) failure rate
- Thickest, strongest graft with nearly twice the cross-sectional area of a patellar tendon graft and 20% more collagen fibrils per cross-section
- Much lower incidence of kneeling pain
- Excellent results for athletes who do high demand sports and activities
- Reproduces native ACL function
- Harvest site morbidity (pain & loss of function) is lower than other grafts
- Remaining quadriceps tendon outperforms patellar tendon strength by 80%
- Minimally invasive incision resulting in smaller scar
Recovery After ACL Surgery
Recovery from both the quad tendon and patellar tendon ACL reconstructions are similar. Patients are instructed to ice and elevate the knee for the first few days after surgery, but physical therapy is started immediately after surgery. Patients will get up on crutches with a physical therapist in the recovery room. A hinged knee brace is used to support the leg until the musculature can support the knee. Patients can remove their dressings and take a shower over the wound sites 3 days after surgery. A post-op office visit occurs with Dr. Cunningham at 7-10 days.
Outpatient physical therapy is prescribed with patients going 2-3 days per week immediately after surgery. In addition to PT, patients will also do a home exercise program, to maximize the rehabilitation timeline. Patient compliance during the recovery process will help ensure complete healing and an optimal outcome. Initially, PT is focused on restoring knee range of motion and reducing swelling. A patient will remain in the post-operative knee brace until they are able to achieve some quadriceps activation and control which typically takes 2-3 weeks. Patients ride a stationary bike within 1-2 weeks from surgery. At 6 weeks from surgery, some gentle quad strengthening is begun. Patients can ride a bike outdoors at 3 months and start running at 4 months. A full return to high level cutting and pivoting sports may take 9 months.
For further information on the difference between the quad tendon graft and patellar tendon graft ACL reconstruction, and any knee or shoulder care questions, please contact Richard Cunningham, MD. For our Vail, CO office call (970) 476-7220. For our Edwards, CO office call (970) 569-3240. For our Frisco, CO office call (970) 668-3633.