Related Experiment Video
Updated: Jan 21, 2026

A Teleoperated Robotic System-Assisted Percutaneous Transiliac-Transsacral Screw Fixation Technique
Published on: January 6, 2023
ACL reconstruction with adjustable-length loop cortical button fixation results in less tibial tunnel widening
Raul Mayr1, Vinzenz Smekal2, Christian Koidl1
1Department of Trauma Surgery, Medical University Innsbruck, Innsbruck, Austria.
Purpose:
To compare tunnel widening and clinical outcome after anterior cruciate ligament reconstruction (ACLR) with interference screw fixation and all-inside reconstruction using button fixation.
Methods:
Tunnel widening was assessed using tunnel volume and diameter measurements on computed tomography (CT) scans after surgery and 6 months and 2 years later, and compared between the two groups. The clinical outcome was assessed after 2 years with instrumented tibial anteroposterior translation measurements, hop testing and International Knee Documentation Committee (IKDC), Lysholm and Tegner activity scores.
Results:
The study population at the final follow-up was 14 patients with screw fixation and 16 patients with button fixation. Tibial tunnels with screw fixation showed significantly larger increase in tunnel volume over time (P = 0.021) and larger tunnel diameters after 2 years in comparison with button fixation (P < 0.001). There were no significant differences in femoral tunnel volume changes over time or in tunnel diameters after 2 years. No significant differences were found in the clinical outcome scores.
Conclusions:
All-inside ACLR using button fixation was associated with less tibial tunnel widening and smaller tunnels after 2 years in comparison with ACLR using screw fixation. The need for staged revision ACLRs may be greater with interference screws in comparison with button fixation at the tibial tunnel. The clinical outcomes in the two groups were comparable.
Level Of Evidence:
II. RCT: Consort NCT01755819.
Related Concept Videos
Fixation and Sectioning
The simplest type of preparation is the wet mount, in which the specimen is placed in a drop of liquid on the slide. A liquid specimen can be directly deposited on the slide using a dropper. Solid specimens, such as skin scraping, can be placed on the slide before adding a drop of liquid to prepare the wet mount. Sometimes the liquid is simply water, but stains are often added...
Carbon-dioxide Fixation
Interference and Diffraction
RNA Interference
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
Self-Locking Screw
A square-threaded screw jack carrying a load is considered self-locking if the screw retains its position even after the moment applied to it is removed.
Cardiopulmonary Resuscitation II: ACLS Airway Management

