Choosing Your ACL Graft
Authors
A guide to the options available — autograft vs allograft — and how each affects your surgery and recovery.
When planning ACL reconstruction, one of the most important decisions is graft selection. There is no single best graft for every patient — the right choice depends on your age, activity level, sport, anatomy, and specific risk profile. Dr Sundaraj will guide you through this decision at your consultation, but the following overview outlines the main options and what to expect from each.
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), Public domain, via Wikimedia Commons
Autograft vs Allograft
ACL grafts come from one of two sources: your own body (autograft) or a carefully processed donor tendon (allograft). Autografts have historically been considered the gold standard, particularly in young and high-demand athletes, owing to their reliable biological incorporation and lower re-rupture rates in this cohort. The trade-off is donor site morbidity — the harvested tendon leaves a gap that must heal, and this can contribute to early weakness, discomfort, or specific functional deficits depending on which tissue is taken. Allografts eliminate donor site morbidity entirely and allow for a less invasive procedure with a smaller incision, which can simplify rehabilitation in the early weeks. The concern with traditional allografts has been a higher re-rupture rate in younger, active patients — a finding linked to the sterilisation process used. Modern supercritically sterilised allografts from young donors have substantially addressed this concern, and represent a highly viable option across a broader range of patients than was once accepted.
The Joint Clinic, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons
Hamstring Tendon (Gracilis & Semitendinosus)
Autograft
The hamstring graft, harvested from the gracilis and semitendinosus tendons on the inner aspect of the knee, has been the most widely used ACL graft in Australia over the past two decades. The tendons are folded to create a four-strand construct (quadrupled graft), producing a strong, flexible graft with good biological compatibility. The harvest site is relatively low-morbidity compared to bone-tendon-bone grafts, and the tendons do regenerate over time — though the regenerated tissue differs from the original.
Advantages
Minimal anterior knee pain post-op
Smaller incision than patellar tendon
No bone block — purely soft tissue fixation
Tendon regrowth occurs over time
Strong long-term outcomes data
Considerations
Higher re-rupture rate vs patellar tendon in some studies
Graft size can be variable — smaller tunnels in some patients
Hamstring weakness, sometimes permanent
Scar tissue around reformed tendon can retear
Graft diameter dependent on patient anatomy
Patellar Tendon (Bone-Tendon-Bone)
Autograft
The patellar tendon graft — harvested as a central third strip with a bony plug at either end — is one of the most extensively studied ACL grafts in the world and has long been considered a benchmark option, particularly for elite athletes and those returning to high-demand pivoting sports. The bone blocks allow for direct bony healing within the tunnels, which is generally faster and more secure than soft tissue fixation. This makes it particularly attractive where graft incorporation speed matters, and where the surgeon wishes to avoid the variability associated with soft tissue graft diameter.
Advantages
Bone-to-bone healing — reliable incorporation
Predictable graft dimensions
Lowest re-rupture rate in some meta-analyses
Preferred by many surgeons for elite athletes
Strong decades-long outcomes data
Considerations
Anterior knee pain and kneeling discomfort (patella donor site)
Risk of patellar fracture or tendon rupture at harvest site (rare)
Technically more demanding surgery
Early quad inhibition due to anterior pain
Larger incision than hamstring
Risk of patella baja and arthritis
Quadriceps Tendon
Autograft
The quadriceps tendon graft has grown substantially in popularity over the past decade. Harvested from the distal quadriceps tendon above the patella, it offers a large, robust graft with excellent mechanical properties. It can be harvested with or without a patellar bone plug, giving surgical flexibility. The harvest site sits proximal to the patella, generally sparing the patient the anterior knee pain that characterises patellar tendon harvest. The quadriceps tendon is notably thick, making it well-suited to patients with larger frames or those requiring a high-strength graft.
Advantages
Large graft cross-section — strong mechanical properties
Less anterior knee pain than patellar tendon
Can include bone plug for tunnel healing if desired
Growing evidence base supporting good outcomes
Considerations
Suprapatellar scar can cause discomfort when kneeling
Risk patella fracture
Quad weakness that may persist
More demanding rehab than hamstring
Less long-term data than patellar tendon or hamstring
Rectus Femoris Tendon
Autograft
The rectus femoris tendon is a less commonly used autograft option, though it holds a specific role in the surgical armamentarium — particularly in revision ACL surgery where conventional harvest sites have already been used, or in patients with anatomy or prior injury that makes standard graft harvest inadvisable. The tendon is harvested from the proximal portion of the rectus femoris and can provide an adequate graft with reasonable biomechanical properties. It is not typically a first-line choice in primary ACL reconstruction given the more limited evidence base, but it represents a valuable alternative when other options are unavailable or have been exhausted.
Advantages
Viable option when wanting to avoid other graft morbidity
Useful in revision and complex settings
Does not compromise patellar or hamstring function
Very large graft dimensions in most patients
Considerations
Emerging evidence compared with autograft options
Quad weakness during recovery
Technically demanding dissection
Risk of proximal avulsion or reinjury
As with all operations, if at any stage anything seems amiss, it is better to call for advice rather than wait and worry. A fever, redness or swelling around the line of the wound or an unexplained increase in pain should all be brought to the surgeon's attention. You can contact Dr Sundaraj by telephoning his staff during business hours or the Mater Hospital after hours. For any questions, please do not hesitate to contact our staff (02) 9437 5999 For after-hour assistance contact Mater Hospital (02) 9900 7300 Further information is available on our website
Get in touch.
Fill out the form and one of the team will be back in touch within 24 hours.
Alternatively, give us a call on
(02) 9437 5999