Background: Biomechanical studies have shown double-bundle (DB) anterior cruciate ligament reconstruction (ACLR) to have increased anterior and rotational stability as compared with single-bundle ACLR. Various techniques exist to drill the femoral tunnel, such as anteromedial portal (AMP), outside-in (OI), and transtibial (TT) drilling. However, it is unclear whether one drilling technique is superior to others when a DB graft is used.
Purpose: To systematically assess the outcomes and complications in patients undergoing DB ACLR through an AMP technique as compared with other femoral drilling techniques.
Study design: Systematic review; Level of evidence, 3.
Methods: PubMed, Medline, and EMBASE databases were searched in April 2018. Nonrandomized studies were assessed with the MINORS (Methodological Index for Nonrandomized Studies), whereas randomized studies were assessed with the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system.
Results: Ten studies comprising 722 patients satisfied the inclusion criteria. A total of 351 patients underwent DB ACLR with AMP drilling (mean ± SD age, 32.7 ± 4.7 years); 318 patients had DB ACLR with OI drilling (age, 31.9 ± 4.1 years); and 53 received a DB ACLR with TT drilling (age, 26.5 ± 2.0 years). Graft types used included hamstring autograft (74.1%; n = 247), tibialis anterior autograft (6.0%; n = 20) and unspecified grafts (19.8%; n = 66). No significant difference in postoperative Tegner and Lysholm scores was found between the AMP and OI groups postoperatively. The AMP group had a lower anterior and posterior graft bending angle as compared with the OI group. Four patients (1.1%) in the AMP group had graft reruptures, as compared with 9 reruptures (2.8%) in the OI group. There were no reports of rerupture in the TT group.
Conclusion: DB AMP ACLR results in significantly improved functional outcome scores postoperatively. AMP techniques yield similar functional outcomes to OI ACLR. No direct comparison in functional outcomes scores were available between the AMP and TT techniques. Low overall complication and revision rates were observed for patients undergoing DB AMP ACLR and were found to be similar to those of other femoral drilling techniques. Owing to a steeper graft bending angle in patients undergoing OI or TT ACLR relative to AMP ACLR, patients treated with OI or TT femoral drilling may have increased strain placed on the graft. Based on the various limitations in the available literature, it is not currently possible to make a definite conclusion of whether AMP is superior to non-AMP techniques in the setting of DB ACLR.
Keywords: anterior cruciate ligament; anteromedial portal; double-bundle; knee; outside-in.
© The Author(s) 2019.
Conflict of interest statement
One or more of the authors has declared the following potential conflict of interest or source of funding: O.R.A. has received educational consulting fees from Conmed and Smith & Nephew. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.
Femoral and Tibial Graft Tunnel Parameters After Transtibial, Anteromedial Portal, and Outside-In Single-Bundle Anterior Cruciate Ligament ReconstructionM Osti et al. Am J Sports Med 43 (9), 2250-8. PMID 26138734.The AMP and OI surgical techniques were superior in positioning the ACL femoral tunnel at the center of the native ACL attachment site compared with the TT technique. An …
Systemic Review of Anatomic Single- Versus Double-Bundle Anterior Cruciate Ligament Reconstruction: Does Femoral Tunnel Drilling Technique Matter?Y Zhang et al. Arthroscopy 32 (9), 1887-904. PMID 27184099. - ReviewAnatomic DB-ACLR showed better anterior and rotational stability and higher objective IKDC score than anatomic SB-ACLR via TT drilling technique. Via independent drilling …
Knee Moment and Shear Force Are Correlated With Femoral Tunnel Orientation After Single-Bundle Anterior Cruciate Ligament ReconstructionH Wang et al. Am J Sports Med 42 (10), 2377-85. PMID 25062662.Knee joint kinetic changes are seen within months (~10 months) after ACLR. This study revealed significant relationships between femoral tunnel orientation and postoperat …
Outside-In vs. Anteromedial Portal Drilling During Primary ACL Reconstruction: Comparison at Two YearsT CarlLee et al. Iowa Orthop J 37, 117-122. PMID 28852345.ACL reconstruction using the AM technique yielded lower radiographic coronal tunnel angle and slightly decreased knee extension. The theoretical risk of graft failure sec …
Better Rotational Control but Similar Outcomes With the Outside-In Versus the Transtibial Drilling Technique for Anterior Cruciate Ligament Reconstruction: A Systematic Review of Comparative TrialsG Ji et al. Arch Orthop Trauma Surg 138 (11), 1575-1581. PMID 29948227. - ReviewNo statistically significant differences were found in clinical functional results when comparing patients who underwent ACL reconstruction with the TT or OI techniques. …
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