2015 ISAKOS Biennial Congress ePoster #1338

Relationship Between the Femoral Bone Tunnels Postion and the Clinical Results in Anatomic Double-Bundle ACL Reconstruction

Atsushi Ichiba, MD, PhD, Ibaraki, Osaka JAPAN
Fumihito Tokuyama, MD, Ibaraki, Osaka JAPAN
Kaoru Makuya, MD, Takarazuka, Hyogo JAPAN
Kosaku Oda, MD, PhD, Ashiya, Hyogo JAPAN

Takatsuki Red Cross Hospital, Takatsuki, Osaka, JAPAN

FDA Status Not Applicable

Summary: Femoral tunnles position has relationship with knee stability

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Abstract:

Background

Which fiber bundles of the anterior cruciate ligament (ACL) should be reconstructed during anatomic double-bundle (DB) ACL reconstruction remains controversial.

Purpose

This study aimed to assess the position of the femoral bone tunnels using three-dimensional computed tomography (3-DCT) and the relationship between bone tunnel position and clinical outcomes of anatomic DB ACL reconstruction. Case-control study.

Methods

Study subjects included 36 patients (23 men, 13 women; mean age, 28.7 years) who underwent anatomic DB ACL reconstruction with hamstring tendons; they underwent 3-DCT on the 10th postoperative days. Clinical assessment was performed 1 year after surgery.
In the sagittal section of the femur on CT, the positions of the tunnels for anteromedial (AM) and posterolateral (PL) grafts were investigated. Lines were drawn perpendicular to the lateral intercondylar ridge (LIR), and a point of intersection (C) was identified between the line and bone-cartilage margin of the medial aspect of the lateral femoral condyle. A line (A) was drawn at the point of maximum distance between the LIR and point C. The midpoint (M) on the line A was identified, and a line (PR) was drawn parallel to the LIR that passed through the point M.
The knees in which the center of the bone tunnel was proximal to the LIR were classified into group P, those in which the center of the bone tunnel was between the LIR and PR were classified into group N, and those in which the center of the bone tunnel was distal to PR were classified into group D. Additionally, knees in which both the AM and PL bone tunnels were between the LIR and PR were included in the NN group, whereas all other knees were classified as “others.” The relationship between the bone tunnel position and clinical outcomes was examined. Data are presented as mean ± standard deviation. The ?2 test or Student t-test was used. Differences were considered significant at P < 0.05.

Results

Considering the AM tunnels, 10 cases were assigned to group P, 21 cases to group N, and 5 cases to group D. Considering the PL tunnels, no cases were assigned to group P, 22 cases to group N, and 14 cases to group D. We observed no relationship between the AM and PL positions with the clinical outcomes.
Fourteen cases were assigned to group NN, and 22 cases to “others.” A negative Lachman test was observed in 93% cases in the NN group and in 73% cases in the “others” (P = 0.14). All cases in the NN group and 84% in the “others” had a negative pivot shift test (P = 0.21). The results of anterior laxity (KT-1000, side-to-side difference) was -0.071 ± 1.9 mm in the NN group and 1.1 ± 1.6 mm in the “others” (P = 0.05). The Lysholm score and IKDC evaluation results were not significantly different between the 2 groups.

Conclusion

Stability tends to be good in knees in which the AM and PL positions are between the LIR and PR.