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Original Article · Open access

Comparisons of the radiological and functional results of femoral tunnels created in Figure-4 and 110° flexion positions in arthroscopic anterior cruciate ligament reconstruction

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Fatih Emre Topsakal

Department of Orthopedics and Traumatology, Erzurum City Hospital, Erzurum, Türkiye

ORCID: 0000-0002-6033-0795

Emre Gültaç

Department of Orthopedics and Traumatology, Muğla Sıtkı Koçman University Faculty of Medicine, Muğla, Türkiye

ORCID: 0000-0003-1943-2199

Cem Yalın Kılınç

Private Clinic of Orthopedics and Traumatology, Muğla, Türkiye

ORCID: 0000-0003-2568-0500

Fatih İlker Can

Department of Orthopedics and Traumatology, Muğla Training and Research Hospital, Muğla, Türkiye

ORCID: 0000-0001-5880-5336

Hıdır Tanyıldızı

Merkez Prime Hospital Clinic of Orthopedics and Traumatology, Kocaeli, Türkiye

ORCID: 0000-0002-7498-7296

Çağatay Gemci

Department of Orthopedics and Traumatology, Bursa Yüksek İhtisas Training and Research Hospital, Bursa, Türkiye

ORCID: 0000-0003-4092-2248

Nevres Hürriyet Aydoğan

Department of Orthopedics and Traumatology, Muğla Sıtkı Koçman University Faculty of Medicine, Muğla, Türkiye

ORCID: 0000-0002-1837-2676

Abstract

Objectives: The aim of this study was to compare the radiological and functional results of femoral tunnels created in Figure-4 and 110° flexion positions in anterior cruciate ligament (ACL) reconstruction.

Patients and methods: Between January 2016 and December 2019, a total of 84 patients (78 males, 6 females; mean age: 29.2±6.1 years; range, 17 to 46 years) who underwent anatomic ACL reconstruction (ACLR) were retrospectively analyzed. The patients were divided into two groups according to femoral tunnel drilling technique: 110° knee flexion (Group 1) and the Figure-4 position (Group 2). Demographic data were recorded. Radiological measurements (femoral tunnel position, length, angles, and distances to the lateral epicondyle) were performed on postoperative Day 1 computed tomography (CT) scans. Functional scores (Lysholm, Cincinnati, IKDC-SKF, Tampa Kinesiophobia, Return to Sport) were assessed at 12 months postoperatively. Radiological and functional outcomes were compared between groups.

Results: The mean anterior distance and axial tunnel angle were higher in the 110° flexion group than in the Figure-4 group (AD: p=0.001; ATA: p=0.035). The superior distance, femoral tunnel length, coronal tunnel angle, and femoral tunnel positioning measurements were significantly higher in the Figure-4 group (SD: p=0.001; FTL: p=0.006; CTA: p=0.001; FTP deep-shallow: p=0.001; FTP highlow: p=0.001). The Cincinnati Knee Rating System scores were also significantly higher in the Figure-4 group (p=0.001).

Conclusion: Anterior cruciate ligament reconstruction using the Figure-4 method provides satisfactory and comparable results with the conventional method. The Figure-4 position allows for 130 to 140º flexion of the knee and tunneling closer to the anatomical ACL insertion owing to the ease of application without creating any operational difficulties.

Declarations

Author Contributions

Idea/concept: F.E.T., N.H.A.; Design: F.E.T., E.G., N.H.A.; Control/supervision: N.H.A.; Data collection and/or processing: F.E.T., C.Y.K., F.İ.C., H.T., Ç.G.; Analysis and/or interpretation, literature review, writing the article: E.G., F.E.T.; Critical review: N.H.A.

Conflict of Interest

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Financial Disclosure

The authors received no financial support for the research and/or authorship of this article.

Data Sharing Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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