Patellar Tendon Harvest Techniques for ACL Reconstruction
The patellar tendon autograft is a common graft choice for ACL reconstruction surgery. However, harvesting the central third of the patellar tendon can lead to donor site morbidity including anterior knee pain, kneeling difficulty, and numbness.1 Surgical technique modifications may reduce these complications.
Traditional Single Incision Technique
The traditional technique uses a single 7-8 cm longitudinal incision over the central patellar tendon.2 The paratenon is opened, and the central third of the tendon lifted directly off the patella and tibial tubercle. This sacrifices the infrapatellar nerve, causing frequent numbness.3
Subcutaneous Two Incision Technique
A modification uses two smaller vertical incisions without opening the paratenon.4 The distal bone block is harvested first through a 2.5 cm tibial incision. Proximal traction delivers the tendon graft subcutaneously. The proximal bone block is then harvested through a separate 2.5 cm incision. This spares the infrapatellar nerve in most cases.
In a prospective study of 124 patients, the two incision technique resulted in significantly less anterior knee numbness (median 0 vs 24 cm2) and a tendency toward less kneeling difficulty at 2 years follow-up.5 ACL stability, range of motion, and activity levels were otherwise equivalent.
A randomized trial of 80 patients found less numbness and lower graft site pain at 3 months with the two incision method.6 However, no difference was seen in kneeling ability.
In summary, the subcutaneous two incision harvest technique better preserves infrapatellar nerve function and reduces some donor site morbidity compared to traditional single incision harvest. Further study on optimal pain control and rehabilitation protocols is still needed.
1. Breitfuss H, Fröhlich R, Povacz P, Resch H. The tendon defect after anterior cruciate ligament reconstruction using the midthird patellar tendon-a problem for the patellofemoral joint? Knee Surg Sports Traumatol Arthrosc. 1996;3(4):194-198.
2. Terry GC, Janssen EW. ACL reconstruction with patellar tendon graft. Sports Med Arthrosc Rev. 1997;5(2):136-40.
3. Kartus J, Ejerhed L, Eriksson BI, et al. The localization of the infrapatellar nerves in the anterior knee region with special emphasis on central-third patella tendon harvest. A dissection study on cadaver and amputated specimens. Arthroscopy. 1999;15(6):577-86.
4. Kartus J, Stener S, Lindahl S, et al. Complications following arthroscopic anterior cruciate ligament reconstruction. A 2-5 year follow-up of 604 patients with special emphasis on anterior knee pain. Knee Surg Sports Traumatol Arthrosc. 1999;7(1):2-8.
5. Kartus J, Ejerhed L, Sernert N, et al. Comparison of traditional and subcutaneous patellar tendon harvest. A prospective study of donor site-related problems after anterior cruciate ligament reconstruction using different graft harvesting techniques. Am J Sports Med. 2000;28(3):328-35.
6. Franciozi CE, Ambra LF, Albertoni LJB, et al. Anterior cruciate ligament reconstruction: a randomized controlled trial of tourniquet versus no tourniquet use. The Knee. 2014;21(4):786-90.