Quad Tendon Q&A with John Xerogeanes, MD
Why should I consider using a quadriceps tendon graft?
The quad tendon is an excellent ACL graft source and an equal and in some areas superior alternative to both the hamstring and patella tendon grafts.
Is the QT graft stronger than the bone-patella tendon-bone (BPTB) graft?
The ultimate load of a 10 mm wide QT is almost 30% higher than a 10 mm wide BPTB. Also, while it is significantly stronger, the modulus (how the tissue acts) is significantly closer to that of the native ACL.* data on file
How does the QT compare histologically to the BPTB graft?
QT had 20% more collagen per cross sectional area than the BPTB.
Do you see QT ruptures after harvesting a QT graft?
No. The intact quad tendon is significantly larger than the intact patella tendon. Interestingly, after the harvest of a typical 10 mm wide QT graft, the remaining quadriceps tendon is 20% stronger than the intact patella tendon.
What are the other advantages of the all-soft tissue QT graft over B-PT-B graft?
The graft is stronger, has superior histology, is almost twice as thick as the PT and thus, produces a graft with 88% more intraarticular volume than an equal width BPTB graft, can be utilized on every age and size patient, produces no anterior knee numbness, and had minimal incidence of post operative frontal knee pain, is faster to harvest and is cosmetically superior.* data on file
What are the advantages of a QT graft over a hamstring graft? 
The biggest advantage is that its size (length and girth) are easily predicted using a simple preoperative measurement on a standard MRI, thus avoiding the small, short graft. There is also no permanent muscle weakness or anterior leg numbness which is often seen when utilizing the hamstring graft.
How does the harvest time compare to the other grafts?
It takes less than 10 minutes to harvest the QT graft and close the wound. This is compared to 25 minutes for the patella tendon graft and 15 minutes for the hamstring.
Is graft size easily predictable?
Yes, unlike a hamstring graft, the QT’s cross sectional area can be easily determined by looking at a standard sagittal cut on the preoperative MRI.
Is the length of the potential graft predictable?
The length of the potential graft was determined through MRI studies and correlated to the height of the patient. In patients over 5 feet tall, 90% of patients have potential graft lengths of over 7 cm. This value can be increased by 2 cm in every patient by harvesting into the myotendinous area of the rectus femoris.
Is the graft suitable for all sizes and ages of people?
Yes, because it is an all-soft tissue graft it can be used in patients of all ages. Also, unlike hamstring grafts the cross sectional area and length is sufficient to allow a graft greater than 7 mm diameter in patients older than 7 years old.
Do you have to have a more conservative postoperative treatment plan compared to a BPTB graft?
No, a standard accelerated ACL rehabilitation plan can be utilized (ACLrehab.org). In fact, since frontal knee pain is not a concern, we can actually be more aggressive in quad strengthening compared to a BPTB graft.
How long does the graft need to be?
The average length of the ACL is 2.5 to 3 cm. Most surgeons want 2 cm of graft in each tunnel, thus 7 cm is the perfect length.
Is soft tissue graft fixation sufficient?
Yes, there are long-term outcomes published by both Shelton and Fulkerson showing that suture suspensory fixation of the soft tissue graft leads to excellent outcomes. My short-term outcomes, 0-3 years and nearly 300 grafts have equal outcomes to both BPTB and HS grafts, with no significant changes in KT values from six weeks to six months.
Is QT graft suitable for a revision surgery?
Secondary to its cross sectional area and its strength, it is an excellent graft for revision surgery. It is easy to harvest graft diameters equal to or greater than 11 mm. This is especially true if the previous tunnels were placed properly and a larger diameter graft is needed.
If a surgeon is considering using a QT graft, what steps should he take to prepare himself?
I would recommend first familiarizing oneself with the anatomy. Our article in the October 2013 issue of AJSM (Xerogeanes et al) is a good resource. Second, start looking at your MRIs. Measure the thickness of the quad tendon on the mid sagittal cut of the MRI and compare it to the thickness of the PT on the same cut. Thirdly, familiarize yourself with the TightRope® RT and the FiberLoop®. Next, try passing your graft through the AM auxillary portal. Lastly, view the technique video the Minimally Invasive Quad Tendon Harvest for ACL Reconstruction technique video.
Are there long-term outcomes?
Yes, there are multiple studies referenced in the Minimally Invasive Quad Tendon Harvest System Surgical Technique Guide showing that the quadriceps tendon both with or without a bone plug have long-term outcomes equal to that of both the patella and hamstring tendons. Shelton, Geib, Fulkerson and Staubli are just some of the authors who have published these studies.
Are the harvest instruments essential to harvesting the tendon?
Yes, these instruments were designed specifically to make harvest of the QT reproducible, safe and easy. Also, they are essential to allow usage of a small cosmetic incision.
What are the specific advantages of the harvest instruments?
The graft knife comes in sizes that will allow different widths for the surgeon to customize the size of the graft. The most commonly used size is the 10 mm width. This blade also is set with a depth stop and a 7 mm deep blade so the surgeon can avoid violating the joint capsule if he chooses to use a partial thickness graft. It also has length measurements so the surgeon can accurately control the length of the cut. The Graft Cutter can perform two functions. It can strip the graft free of proximal soft tissue attachments and then transect the graft at a specific length. This enables time efficiency and the need for multiple or large graft harvest incisions.
Are there any complications unique to the quad tendon graft?
The unique complications are seen when a graft is greater than8 cm in length is harvested. During these harvests, the rectus femoris is violated. The complications that can be seen are bleeding in the thigh. Thus, all patients’ thighs are palpated in the recovery room prior to discharge to make sure they are not tense. The other complication is cosmetic with a retraction of the rectus femoris muscle. This does not affect the patient’s strength. Again, these complications are extremely rare and only seen with proximal harvests.
Do you like an All-Inside® technique?
Yes, the All-Inside technique basically changes two things done historically; Pass the graft through the AM auxillary portal and drill sockets instead of complete tunnels. This dramatically changes the ease of graft passage and saves native bone stock. It also decreases surgical time.
If you want to drill traditionally, are there any parts of the All-Inside® technique you would still recommend?
Yes, I would still recommend passing the graft through the aux AM portal into the femur, then retrograde through the tibia. This will allow you to avoid the sharp turns when performing an anatomic ACL preservation.
References:
Xerogeanes JW, Mitchell PM, Karasev PA, Kolesov IA, Romine SE. Anatomic and morphological evaluation of the quadriceps tendon using 3-dimensional magnetic resonance imaging reconstruction: applications for anterior cruciate ligament autograft choice and procurement. Am J Sports Med. 2013 Oct;41(10):2392-9. doi: 10.1177/0363546513496626. Epub 2013 July 26.
DeAngelis JP, Fulkerson JP. Quadriceps tendon: a reliable alternative for reconstruction of the anterior cruciate ligament. Clin Sports Med, 2007;26(4):587-596.
Fulkerson JP. Central quadriceps free tendon for anterior cruciate ligament reconstruction. Oper Tech Sports Med. 1999;7:195-200.
Geib TM, Shelton WR, Phelps RA, Clark L, Anterior cruciate ligament reconstruction using quadriceps tendon autograft: intermediate-termoutcome. Arthroscopy. 2009;25(12): 1408-1414.
Harris NL, Smith DA, Lamoreaux L, Purnell M, Central quadriceps tendon for anterior cruciate ligament reconstruction, part I: morphometric and biomechanical evaluation. Am J Sports Med. 1997; 25(1):23-28.
Lippe J, Armstrong A, Fulkerson JP, Anatomic guidelines for harvesting a quadriceps free tendon autograft for anterior cruciate ligament reconstruction. Arthroscopy. 2012;28(7): 980-984.
Staubli HU, Bollmann C, Kreutz R, Becker W, Rauschning W, Quantification of intact quadriceps tendon, quadriceps tendon insertion, and suprapatellar fat pad: MR arthrography, anatomy, and cryosections in the sagittal plane. AJR Am J Roentgenol. 1999;173(3):691-698.
Staubli HU, Schatzmann L, Brunner P, Rincon L, Nolte LP, Quadriceps tendon and patellar ligament: cryosectional anatomy and structural properties in young adults. Knee Surg Sports Traumatol Arthrosc. 1996;4:100-110.
