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In Vitro Application of a Wireless Sensor in Flexion-Extension Gap Balance of Unicompartmental Knee Arthroplasty
Published on: May 5, 2023
966
Midflexion instability in total knee arthroplasty: a systematic review
Umile Giuseppe Longo1, Vincenzo Candela2, Francesco Pirato2
1Department of Orthopaedic and Trauma Surgery, Campus Bio-Medico University, Via Alvaro del, Portillo, 200, Trigoria, 00128, Rome, Italy. g.longo@unicampus.it.
Summary
Midflexion instability in total knee arthroplasty is not fully understood. Excessive anteroposterior translation (≥7mm) is a risk factor, while joint line position and posterior condylar offset also influence stability.
Area of Science:
- Orthopedic surgery
- Biomechanical engineering
- Arthroplasty research
Background:
- Midflexion instability is a potential complication following primary total knee arthroplasty (TKA).
- Understanding the factors contributing to midflexion instability is crucial for improving TKA outcomes.
Purpose of the Study:
- To systematically review existing evidence on the existence of midflexion instability in primary TKA.
- To identify factors that may contribute to the development of midflexion instability.
Main Methods:
- A comprehensive literature search was conducted across multiple databases (PubMed, Medline, Cochrane, CINAHL, Embase) up to July 2019.
- Seven relevant studies were included after rigorous screening of 28 initially identified articles.
- Analysis focused on anteroposterior translation, TKA design, joint line position, posterior condylar offset, and joint gaps.
Main Results:
- Anteroposterior translation of 7 mm or more was identified as an independent risk factor for midflexion instability at 30° flexion.
- Joint line position could be adjusted by up to 5 mm without significant impact on joint stability.
- Both increases and decreases in posterior condylar offset were associated with midflexion instability at 30°.
Conclusions:
- Midflexion instability in primary TKA is not completely understood, with limited high-quality evidence.
- While several factors influencing stability were identified, definitive conclusions are challenging.
- This review serves as a foundation for future research and emphasizes the need for routine assessment of midflexion instability in TKA.
