Related Experiment Video
Updated: Jan 27, 2026

Orthopedic Robot-Assisted Femoral Neck System in the Treatment of Femoral Neck Fracture
Published on: March 3, 2023
Can the use of femoral notch view alone decrease measurement error of distal interlocking screws after retrograde
Boshen Liu1, David A Zuelzer1, Jerad Allen1
1Department of Orthopaedic Surgery and Sports Medicine, University of Kentucky, Lexington, KY, USA.
Objectives:
Determine if using different fluoroscopic views of the knee (Notch or Tangential) improves accuracy of screw lengths assessment compared to the standard posteroanterior (PA).
Participants And Methods:
Orthopaedic surgeons at three ACGME-accredited residency programs were asked via survey to assess screw lengths on PA, femoral notch, and tangential radiographic views.
Results:
Responders correctly identified screw length using PA, femoral notch, and medial tangential views at rates of 46.75%, 52.27%, and 44.37% respectively. Respondents detected overall screw length discrepancies most accurately using the femoral notch view (Odds Ratio 1.26; 95% confidence interval: 1.07-1.47; P < 0.005). There was no statistical difference between the residents and faculty cohort in ability to detect screw length discrepancy.
Conclusion:
Differentiating distal interlocking screw lengths on traditional imaging (AP/Notch/Tangential) is poor. The femoral notch view significantly improves accuracy in radiographic determination of screw length. The femoral notch view should be used in conjunction with the traditional PA view to maximize sensitivity and specificity for detecting prominent screws.
Related Concept Videos
Decreasing Function
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.
Systematic Error: Methodological and Sampling Errors
Sampling errors originate from improper sampling methods or the wrong sample population. These errors can be minimized by refining the sampling strategy. Defective instruments or faulty calibrations are the sources of instrumental...
Fundamental Attribution Error
Screw: Problem Solving
To evaluate the...
Decreased Body Temperature

