Related Experiment Video
Updated: Jun 13, 2026
07:33
In Vitro Application of a Wireless Sensor in Flexion-Extension Gap Balance of Unicompartmental Knee Arthroplasty
Published on: May 5, 2023
Comparison between two computer-assisted total knee arthroplasty: gap-balancing versus measured resection technique.
Domenico Tigani1, G Sabbioni, R Ben Ayad
1VII Department of Orthopaedic Surgery, Rizzoli Orthopaedic Institute, University of Bologna, Via Pupilli 1, 40136 Bologna, Italy. domenico.tigani@ior.it
Summary
In total knee arthroplasty (TKA), the measured resection technique better preserves joint-line position compared to the gap-balancing technique, especially in moderate deformities. Surgeons can choose based on confidence, but measured resection is preferred for patellar tendon issues.
Area of Science:
- Orthopedic Surgery
- Biomechanical Engineering
- Medical Imaging
Background:
- Total knee arthroplasty (TKA) involves complex bone resections and component alignment.
- Two primary surgical techniques exist: measured resection and gap balancing.
- Optimizing joint-line maintenance and limb alignment is crucial for TKA outcomes.
Purpose of the Study:
- To compare the effects of measured resection and gap-balancing techniques in TKA.
- To analyze joint-line (JL) maintenance, axial limb restoration, and component positioning.
- To evaluate the influence of pre-operative deformity on surgical outcomes.
Main Methods:
- Prospective study of 126 patients undergoing TKA using computer-assisted surgery.
- Comparison of measured resection versus gap-balancing techniques.
- Analysis of post-operative joint-line position, mechanical axis alignment, and component positioning in frontal and sagittal planes.
Main Results:
- The gap-balancing technique resulted in a statistically significant increase in post-operative joint-line elevation (P = 0.008).
- Measured resection showed superiority in preserving pre-operative joint-line position in moderate deformities (<10 degrees) (P = 0.001).
- Both techniques achieved good frontal plane alignment; sagittal plane alignment showed variability due to implant design.
Conclusions:
- Measured resection technique offers better joint-line preservation, particularly in cases with moderate pre-operative deformity.
- While both techniques can achieve good alignment, measured resection is preferable in patients with short patellar tendons or patella infera.
- Surgeons may select techniques based on personal preference, but measured resection provides specific advantages for joint-line restoration.