Summary

The non-circular femoral tunnel ACL reconstruction has some documented advantages when compared to the conventional round technique including early graft healing, decreased tunnel widening, and a smaller cross-sectional area, along with reasonable and comparable clinical outcomes making it a valuable option for primary or revision ACL reconstruction.

Abstract

Purpose

Anatomical studies have shown that the shape of the anterior cruciate ligament, specifically, its femoral attachment is a broad flat structure consisting of two bundles. Additionally, some studies have demonstrated that the conventional single round bundle ACL reconstruction does not adequately restore rotational stability and the rate of return to sport is not favorable. Recently some studies claimed the rectangular or oval femoral tunnel ACL reconstruction resembles more the shape of the native ACL and femoral attachment. This study is aimed to evaluate the use of non-circular femoral tunnel ACL reconstruction as it compares to the conventional round tunnel technique.

Methods

An electronic search was performed using the PubMed and Scopus databases. All therapeutic trials written in English reporting the clinical outcomes of the non-round femoral tunnel were included. Data regarding kinematic tests as well as clinical scores were extracted and included pivot-shift test, Lachman test, KT-1000 measurements, Tegner Activity Scale, Lysholm score, IKDC subjective scale, and knee range of motion.

Results

A total of 22 papers for the rectangle group (n = 1,314) met the inclusion criteria. With an average follow-up of 15.8 months (+/- 10.4 months), the mean reported Lysholm score was 97.8 (+/- 0.80) and the mean reported KT-1000 arthrometer measurement was 1.2 (+/- 1.9). When comparing the rectangle technique to the conventional round, no significant differences were seen regarding Lysholm score or KT-1000 arthrometer measurements at final follow-up. In the oval group, a total of 5 studies (n = 322) met the eligibility criteria. With an average follow-up of 20.2 months (+/- 13.7 months), the mean reported Lysholm score was 94.4 (+/- 2.0), the mean IKDC subjective was 90.4 (+/- 1.2), and the mean KT-1000 arthrometer measurement was 1.6 (+/- 0.4).

Conclusion

The non-circular femoral tunnel ACL reconstruction has some documented advantages when compared to the conventional round technique including early graft healing, decreased tunnel widening, a smaller cross-sectional area, as well as reasonable and comparable clinical outcomes making it a valuable option for both primary or revision ACL reconstruction.