If you are considering ACL reconstruction, one of the important decisions is which graft will be used to replace the torn ligament. The most commonly discussed autograft options include the hamstring tendon, bone-patellar tendon-bone (patellar tendon) graft, and quadriceps tendon graft.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
All three can provide a strong graft for ACL reconstruction, but they differ in where the tissue is taken from, how the graft is prepared, and the potential effects on the area from which it was harvested. There is no single graft that is suitable for every patient.
What Is an ACL Graft?
An ACL graft is a piece of tendon used to reconstruct the torn ACL. During surgery, the graft is positioned inside the knee to perform the stabilizing function of the original ligament.
When tissue is taken from your own body, it is called an autograft. Hamstring, patellar tendon, and quadriceps tendon grafts are all autograft options.
The choice may depend on factors such as your age, activity level, sporting goals, previous surgeries or injuries, the condition of the available tendons, and the surgeon's assessment of your knee.
1. Hamstring Tendon Graft
A hamstring graft uses one or more of the tendons from the muscles at the back of the thigh. The harvested tendon is prepared and folded to create a graft of appropriate size for ACL reconstruction.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
Potential advantages
- Does not involve taking tissue from the kneecap or patellar tendon.
- May result in less anterior knee discomfort than a patellar tendon graft for some patients.
- Has been used extensively for ACL reconstruction, providing a substantial body of clinical experience.
Potential considerations
- Some patients may experience temporary or persistent hamstring strength reduction after graft harvesting.
- The available tendon size can vary between individuals.
- Hamstring strength and rehabilitation need to be considered as part of postoperative recovery.
2. Patellar Tendon Graft
The patellar tendon graft is commonly known as a bone-patellar tendon-bone (BPTB) graft. It uses the central portion of the patellar tendon along with small bone blocks from the kneecap and shinbone. The bone blocks allow the graft to be secured within bone tunnels created during ACL reconstruction.
Potential advantages
- Provides a well-established option for ACL reconstruction.
- Includes bone plugs that can provide bone-to-bone healing within the prepared tunnels.
- May be considered for people with high physical or sporting demands.
Potential considerations
- Pain at the front of the knee can occur after graft harvesting.
- Kneeling may be uncomfortable for some patients.
- The patellar tendon and surrounding structures require appropriate rehabilitation after harvesting.
These potential donor-site symptoms are important to discuss, particularly if your work, sport, or daily activities involve frequent kneeling.
3. Quadriceps Tendon Graft
A quadriceps tendon graft is taken from the tendon above the kneecap. It can be harvested as a soft-tissue graft or, depending on the surgical technique, with a small bone plug.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
Quadriceps tendon grafts have become increasingly used in ACL reconstruction and are now an established alternative to hamstring and patellar tendon grafts. Recent research has found broadly comparable clinical outcomes between quadriceps tendon and other commonly used autografts, although individual studies differ in their findings.
Potential advantages
- Provides a relatively large and strong tendon that can be sized according to the reconstruction requirements.
- May be useful when hamstring or patellar tendon tissue is unsuitable or has previously been harvested.
- Comparative studies suggest that quadriceps tendon grafts can provide similar functional and stability outcomes to hamstring and patellar tendon grafts.
Potential considerations
- Temporary quadriceps weakness may occur after harvesting.
- Rehabilitation needs to address restoration of quadriceps strength and function.
- Because quadriceps tendon harvesting is a different technique from hamstring or patellar tendon harvesting, postoperative recovery can vary.
Hamstring vs Patellar Tendon vs Quadriceps Tendon
| Feature | Hamstring | Patellar Tendon | Quadriceps Tendon |
|---|---|---|---|
| Harvest site | Tendons at the back of the thigh | Central portion of the patellar tendon | Tendon above the kneecap |
| Graft type | Soft-tissue tendon | Bone-patellar tendon-bone | Soft-tissue tendon or tendon with a bone plug |
| Key donor-site consideration | Hamstring weakness | Anterior knee pain or kneeling discomfort | Quadriceps weakness |
| Clinical experience | Extensive | Extensive | Increasing and well established |
This comparison is a general guide rather than a way to determine which graft is right for you. The risks and recovery experience can vary from one person to another.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
What Factors Influence Graft Choice?
Your surgeon may consider several factors before selecting the graft.
Age and activity level
A person who wants to return to competitive sports may have different graft considerations from someone whose main goal is comfortable daily activity.
Sport and physical demands
Activities involving jumping, cutting, pivoting, or rapid changes in direction place substantial demands on the reconstructed ACL and may influence graft selection.
Previous injuries or surgeries
If a tendon has already been harvested or injured, another graft source may be considered. Previous surgery on the same knee can therefore affect the available options.
Donor-site concerns
The effects of harvesting tissue matter because you are not only recovering from the ACL reconstruction itself but also from the area where the graft was taken.
Graft size and tissue quality
The size and quality of the available tendon may influence whether a particular graft is suitable for your reconstruction.
Does Graft Choice Affect Recovery?
Recovery after ACL reconstruction involves much more than the graft itself. Rehabilitation is essential for restoring knee movement, strength, balance, coordination, and confidence.
The graft harvest site can also influence which muscles need particular attention during rehabilitation. For example, quadriceps strength is especially important after a quadriceps tendon or patellar tendon graft, while hamstring strength may receive particular attention after a hamstring graft.
Return to sports should therefore be based on functional recovery, strength, knee stability, movement quality, and other clinical criteria rather than simply the number of weeks since surgery.
The Bottom Line
Hamstring, patellar tendon, and quadriceps tendon autografts are all established options for ACL reconstruction. Each has potential advantages and donor-site considerations, and current evidence does not show one graft to be universally best for every patient.
The right choice depends on your knee, activity goals, previous injuries or surgeries, available tendon tissue, and the specific risks and benefits that matter to you. Understanding these differences can help you have a more informed discussion about which graft may fit your reconstruction and recovery goals.
