Single-Incision Endoscopic ACL Reconstruction


Endoscopic anterior cruciate ligament (ACL) reconstruction techniques have gained popularity as less invasive methods to reconstruct the ACL. This study evaluated outcomes of 103 patients after single-incision endoscopic ACL reconstruction using a patellar tendon autograft without extra-articular augmentation.

Surgical Technique

The procedure utilized a 10mm central third patellar tendon graft fixed in full extension. Femoral tunnel placement was at the 11 o’clock (right knee) or 1 o’clock (left knee) position. Tibial fixation was performed with the knee in full extension with tension on the graft. Early postoperative rehabilitation emphasized immediate weightbearing, range of motion, and closed kinetic chain strengthening.

Clinical Outcomes

At average 36 month follow-up, knee stability was restored. Ninety-four patients (91%) had a negative pivot shift test. Lachman and anterior drawer tests were also significantly improved. The mean side-to-side difference on KT-1000 arthrometer testing was only 1.1mm. Range of motion averaged 1° hyperextension to 137° flexion. Functional testing showed mean deficits of 4-6% compared to the uninjured side. Patient-reported outcome scores were excellent, including a mean Lysholm score of 89 and Noyes score of 90. Ninety-five percent of patients said they would repeat the surgery. Complications occurred in 15% of patients.


The outcomes of this single-incision ACL reconstruction technique compare favorably to other studies of endoscopic and open ACL reconstruction utilizing patellar tendon autografts.2-5 In particular, the stability rates based on pivot shift testing and KT arthrometry are excellent. The incidence of anterior knee pain was only 14%, lower than generally reported after open patellar tendon ACL reconstruction. Accelerated rehabilitation with early motion and weightbearing likely contributed to the good results.

Limitations of this study include the lack of randomization and inclusion of only a single surgeon’s initial experience. Longer-term follow-up is needed. Nonetheless, excellent short-term outcomes were achieved, validating this approach as an effective method for primary ACL reconstruction. Future comparative trials can better define the relative advantages of endoscopic versus open techniques.


1. Bach BR Jr, Levy ME, Bojchuk J, Tradonsky S, Bush-Joseph CA, Khan NH. Single-incision endoscopic anterior cruciate ligament reconstruction using patellar tendon autograft: minimum two-year follow-up evaluation. Am J Sports Med. 1998;26(1):30-40.

2. Harner CD, Marks PH, Fu FH, Silberger JR, Silber JS, Thompson P. Anterior cruciate ligament reconstruction: endoscopic versus two-incision technique. Arthroscopy. 1994;10(5):502-512.

3. O’Neill DB. Arthroscopically assisted reconstruction of the anterior cruciate ligament. A prospective randomized analysis of three techniques. J Bone Joint Surg Am. 1996;78(6):803-813.

4. Arciero RA, Scoville CR, Snyder RJ, Uhorchak JM, Taylor DC, Huggard D. Single versus two-incision arthroscopic anterior cruciate ligament reconstruction. Arthroscopy. 1996;12(4):462-469.

5. Sgaglione NA, Schwartz RE. Comparison of endoscopically and arthroscopically assisted anterior cruciate ligament reconstruction. Arthroscopy. 1994;10(3):329.

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